1245:
dissolved simple silicates, monomeric silica and silicic acid, and an undetermined fraction of polymeric silica. Total silica determination in water employs high resolution ICPMS, GFAA (graphite furnace atomic absorption), and the photometric method combined with silica digestion. For many natural waters, a measurement of molybdate-reactive silica by this test method provides a close approximation of total silica, and, in practice, the colorimetric method is frequently substituted for other more time-consuming techniques. However, total silica analysis becomes more critical in UPW, where the presence of colloidal silica is expected due to silica polymerization in the ion exchange columns. Colloidal silica is considered more critical than dissolved in the electronic industry due to the bigger impact of nano-particles in water on the semiconductor manufacturing process. Sub-ppb (parts per billion) levels of silica make it equally complex for both reactive and total silica analysis, making the choice of total silica test often preferred.
1253:
with the capability of online instruments. The test involves installation of the SEM capture filter cartridge on the UPW sampling port for sampling on the membrane disk with the pore size equal or smaller than the target size of the UPW particles. The filter is then transferred to the SEM microscope where its surface is scanned for detection and identification of the particles. The main disadvantage of SEM analysis is long sampling time. Depending on the pore size and the pressure in the UPW system, the sampling time can be between one week and one month. However, typical robustness and stability of the particle filtration systems allow for successful applications of the SEM method. Application of Energy
Dispersive X-ray Spectroscopy (SEM-EDS) provides compositional analysis of the particles, making SEM also helpful for systems with on-line particle counters.
1616:
characterize the various waste streams and determine the potential of their respective re-use. In the case of UPW process rinse water the lab analysis data can then be used to profile typical and non-typical levels of contamination which then can be used to design the rinse water treatment system. In general it is most cost effective to design the system to treat the typical level of contamination that may occur 80-90% of the time, then incorporate on-line sensors and controls to divert the rinse water to industrial waste or to non-critical use such as cooling towers when the contamination level exceeds the capability of the treatment system. By incorporating all these aspects of a water management plan in a semiconductor manufacturing site the level of water use can be reduced by as much as 90%.
1249:
often choose off-line testing. TOC can be measured in the grab sample at a concentration as low as 5 ppb, using the same technique employed for the on-line analysis (see on-line method description). This detection level covers the majority of needs of less critical electronic and all pharmaceutical applications. When speciation of the organics is required for troubleshooting or design purposes, liquid chromatography-organic carbon detection (LC-OCD) provides an effective analysis. This method allows for identification of biopolymers, humics, low molecular weight acids and neutrals, and more, while characterizing nearly 100% of the organic composition in UPW with sub-ppb level of TOC.
784:
consult at the time of writing are: FDA Guide to
Inspections of High Purity Water Systems, High Purity Water Systems (7/93), the EMEA CPMP/CVMP Note for Guidance on Quality of Water for Pharmaceutical Use (London, 2002), and USP Monograph <1231> Water For Pharmaceutical Purposes. However, other jurisdictions' documents may exist, and it is a responsibility of practitioners validating water systems to consult those. Currently, the World Health Organization (WHO) as well as the Pharmaceutical Inspection Co-operation Scheme (PIC/S) developed technical documents which outline validation requirements and strategies for water systems.
1271:
1378:
1451:
sweeping contaminants to a waste stream, known as the retentate stream. The retentate stream is only a small percentage of the total flow, and is sent to waste. The product water, or the permeate stream, is the UPW passing through the skin of the hollow fiber and exiting through the center of the hollow fiber. The UF is a highly efficient filtration product for UPW, and the sweeping of the particles into the retentate stream yield extremely long life with only occasional cleaning needed. Use of the UF in UPW systems provides excellent particle control to single digit nanometer particle sizes.
1386:
contamination. Larger fabs required larger size UPW systems. The figure below illustrates the increasing consumption driven by the larger size of wafer manufactured in newer fabs. However, for larger pipe (driven by higher consumption) the 60 cm (2& ft) per second criteria meant extremely high consumption and an oversized polishing system. The industry responded to this issue and through extensive investigation, choice of higher purity materials, and optimized distribution design was able to reduce the design criteria for minimum flow, using
Reynolds number criteria.
1516:
1528:
facility. The contamination level of the rinse water can vary a great deal depending on the particular process step that is being rinsed at the time. A "first rinse" step may carry a large amount of residual contaminants and particles compared to a last rinse that may carry relatively low amounts of contamination. Typical semiconductor plants have only two drain systems for all of these rinses which are also combined with acid waste and therefore the rinse water is not effectively reused due to risk of contamination causing manufacturing process defects.
1257:
both the sampling of water lines and the subsequent microbiological analysis of the sample by the culture technique. The microorganisms recovered from the water samples and counted on the filters include both aerobes and facultative anaerobes. The temperature of incubation is controlled at 28 ± 2 °C, and the period of incubation is 48 h or 72 h, if time permits. Longer incubation times are typically recommended for most critical applications. However 48 hrs is typically sufficient to detect water quality upsets.
1633:
771:
811:
most often permanently inserted directly into the main ultrapure water system piping to provide real-time continuous monitoring of contamination. These probes contain both conductivity and temperature sensors to enable accurate compensation for the very large temperature influence on the conductivity of pure waters. Conductivity probes have an operating life of many years in pure water systems. They require no maintenance except for periodic verification of measurement accuracy, typically annually.
1459:
trickle flow is typically maintained to prevent a dead leg in the tool. The filter must be robust to withstand the pressure and low cycling, and must continue to retain captured particles throughout the service life of the filter. This requires proper pleat design and geometry, as well as media designed to optimized particle capture and retention. Certain tools may use a fixed filter housing with replaceable filters, whereas other tools may use disposable filter capsules for the POU UPW.
913:
line-width approaches 10 nm (a human hair is approximately 100,000 nm in diameter) LPC technology is becoming limited by secondary optical effects, and new particle measurement techniques will be required. Recently, one such novel analysis method named NDLS has successfully been brought into use at
Electrum Laboratory (Royal Institute of Technology) in Stockholm, Sweden. NDLS is based on Dynamic Light Scattering (DLS) instrumentation.
1581:
it back in the wafer rinse process. Some additional water treatment may be required for any of these cases depending on the quality of the spent rinse water and the application of the reclaimed water. These are fairly common practices in many semiconductor facilities worldwide, however there is a limitation to how much water can be reclaimed and recycled if not considering reuse in the manufacturing process.
278:
cleaning agent, so it is important that the water not contain dissolved contaminants that can precipitate or particles that may lodge on circuits and cause microchip failures. The power industry uses UPW to make steam to drive steam turbines; pharmaceutical facilities use UPW as a cleaning agent, as well as an ingredient in products, so they seek water free of endotoxins, microbials, and viruses.
1693:
together and the bladder is inflated. After a prescribed period of time the heater head begins to cool and the bladder deflates. Once completely cooled the bladder is removed and the joined components are taken out of the clamping station. The benefit of the BCF system is that there is no weld bead, meaning that the surface of the weld zone is routinely as smooth as the inner wall of the pipe.
840:(DO) concentrations in the ultrapure rinse water to prevent oxidation of wafer films and layers. DO in power plant water and steam must be controlled to ppb levels to minimize corrosion. Copper alloy components in power plants require single digit ppb DO concentrations whereas iron alloys can benefit from the passivation effects of higher concentrations in the 30 to 150 ppb range.
986:, each method being appropriate for different water purity levels. For typical raw waters feeding into the front end of an UPW purification system the raw water can contain TOC levels between 0.7 mg/L to 15 mg/L and require a robust oxidation method that can ensure there is enough oxygen available to completely convert all the carbon atoms in the organic molecules into CO
828:. Because of the logarithmic response, low concentrations in sub-parts per billion ranges can be measured routinely. To prevent interference from hydrogen ion, the sample pH is raised by the continuous addition of a pure amine before measurement. Calibration at low concentrations is often done with automated analyzers to save time and to eliminate variables of manual calibration.
1625:
207:, and, in severe cases, leave unwanted residues on production parts. TOC can come from the feed water used to produce UPW, from the components used to convey the UPW (additives in the manufacturing piping products or extrusion aides and mold release agents), from subsequent manufacturing and cleaning operations of piping systems, or from dirty pipes, fittings, and valves.
1499:(AOP) using systems. This is particularly important when tight TOC specification below 1 ppb is required to be attained. These difficult to control organics have been proven to impact yield and device performance especially at the most demanding process steps. One of the successful examples of the POU organics control down to 0.5 ppb TOC level is AOP combining
1332:
processes. In this instance polished UPW is heated in the range of 70 to 80C before being delivered to manufacturing. Most of these systems include heat recovery wherein the excess hot UPW returned from manufacturing goes to a heat recovery unit before being returned to the UPW feed tank to conserve on the use of heating water or the need to cool the hot UPW return flow.
1590:
Water systems are very effective at removing ionic contamination down to parts per trillion levels (ppt) whereas organic contamination of ultrapure water systems is still in the parts per billion levels (ppb). In any case recycling the process water rinses for UPW makeup has always been a great concern and until recently this was not a common practice. Increasing
820:
hydrogen ion and therefore conductivity measurement is not useful for this purpose. Sodium is also measured in power plant water and steam samples because it is a common corrosive contaminant and can be detected at very low concentrations in the presence of higher amounts of ammonia and/or amine treatment which have a relatively high background conductivity.
1720:
of purity of UPW. Deionized (DI) water may have a purity of at least one million ohms-centimeter or one MΩ⋅cm. Typical UPW quality is at the theoretical maximum of water resistivity (18.18 MΩ⋅cm at 25 °C). Therefore, the term has acquired measurable standards that further define both advancing needs and advancing technology in ultrapure water production.
899:. Most silica analyzers operate on an automated semi-continuous basis, isolating a small volume of sample, adding reagents sequentially and allowing enough time for reactions to occur while minimizing consumption of reagents. The display and output signals are updated with each batch measurement result, typically at 10 to 20-minute intervals.
1069:, this is a simpler oxidation method. The wavelength of the UV light for the lower TOC waters must be less than 200 nm and is typically 184 nm generated by a low pressure Hg vapor lamp. The 184 nm UV light is energetic enough to break the water molecule into OH and H radicals. The hydrogen radicals quickly react to create H
1309:, Demineralization plus reverse osmosis or HERO (high efficiency reverse osmosis). In addition, the degree of filtration upstream of these processes will be dictated by the level of suspended solids, turbidity and organics present in the source water. The common types of filtration are multi-media, automatic backwashable filters and
807:
18.18 MΩ⋅cm at 25 °C, the most common reference temperature to which these measurements are compensated. An example of the sensitivity to contamination of these measurements is that 0.1 ppb of sodium chloride raises the conductivity of pure water to 0.05523 μS/cm and lowers the resistivity to 18.11 MΩ⋅cm.
908:
failure is called a yield loss, one of the most closely watched parameters in the semiconductor industry. The technique of choice to detect these single particles has been to shine a light beam (a laser) through a small volume of UPW and detect the light scattered by any particles (instruments based on this technique are called
1692:
Bead and crevice free (BCF), uses a process of placing two thermoplastic components having the same inner and outer diameters together. Next an inflatable bladder is introduced in the inner bore of the components and placed equidistance within the two components. A heater head clamps the components
1589:
Recycling rinse water from the semiconductor manufacturing process has been discouraged by many manufacturing engineers for decades because of the risk that the contamination from the chemical residue and particles may end up back in the UPW feed water and result in product defects. Modern
Ultrapure
1256:
Bacteria analysis is typically conducted following ASTM method F1094. The test method covers sampling and analysis of high purity water from water purification systems and water transmission systems by the direct sampling tap and filtration of the sample collected in the bag. These test methods cover
978:
is most commonly achieved in liquid solutions by the creation of the highly oxidizing chemical species, the hydroxyl radical (OH•). Organic oxidation in a combustion environment involves the creation of other energized molecular oxygen species. For the typical TOC levels in UPW systems most methods
921:
Another type of contamination in UPW is dissolved inorganic material, primarily silica. Silica is one of the most abundant minerals on the planet and is found in all water supplies. Any dissolved inorganic material has the potential to remain on the wafer as the UPW dries. Once again this can lead to
912:
or LPCs). As semiconductor manufacturers pack more and more transistors into the same physical space, the circuitry line-width has become narrow and narrower. As a result, LPC manufacturers have had to use more and more powerful lasers and very sophisticated scattered light detectors to keep pace. As
907:
Particles in UPW have always presented a major problem for semiconductor manufacture, as any particle landing on a silicon wafer can bridge the gap between the electrical pathways in the semiconductor circuitry. When a pathway is short-circuited the semiconductor device will not work properly; such a
334:
where the highest grade of purity is required. The amount of electronic-grade or molecular-grade water used by the semiconductor industry is comparable to the water consumption of a small city; a single factory can utilize ultrapure water (UPW) at a rate of 2 MGD, or ~5500 m/day. The UPW is
1696:
Infrared fusion (IR) is a process similar to CBF except that the component ends never touch the heater head. Instead, the energy to melt the thermoplastic is transferred by radiant heat. IR comes in two variations; one uses overlap distance when bringing the two components together while the other
1580:
is also a typical application where spent rinse water from the manufacturing facility may be used in cooling tower supply, exhaust scrubber supply, or point of use abatement systems. UPW Recycling is not as typical and involves collecting the spent manufacturing rinse water, treating it and re-using
1466:
applications, small filter capsules are used. Similar to the challenges for wet etch and clean POU UPW applications, for lithography UPW rinse, the flow through the filter is intermittent, though at a low flow and pressure, so the physical robustness is not as critical. Another POU UPW application
1393:
Another capacity consideration is related to operability of the system. Small lab scale (a dozen liters-per-minute/few gallons-per-minute-capacities) systems do not typically involve operators, while large scale systems usually operate 24x7 by well trained operators. As a result, smaller systems are
1389:
The figure on the right illustrates an interesting coincidence that the largest diameter of the main supply line of UPW is equal to the size of the wafer in production (this relation is known as
Klaiber's law). Growing size of the piping as well as the system overall requires new approaches to space
1331:
Polishing consists of UV, heat exchange to control constant temperature in the UPW supply, non-regenerable ion exchange, membrane degasification (to polish to final UPW requirements) and ultrafiltration to achieve the required particle level. Some semiconductor Fabs require hot UPW for some of their
1278:
Typically, city feed-water (containing all the unwanted contaminants previously mentioned) is taken through a series of purification steps that, depending on the desired quality of UPW, includes gross filtration for large particulates, carbon filtration, water softening, reverse osmosis, exposure to
1221:
When testing the quality of UPW, consideration is given to where that quality is required and where it is to be measured. The point of distribution or delivery (POD) is the point in the system immediately after the last treatment step and before the distribution loop. It is the standard location for
819:
Sodium is usually the first ion to break through a depleted cation exchanger. Sodium measurement can quickly detect this condition and is widely used as the indicator for cation exchange regeneration. The conductivity of cation exchange effluent is always quite high due to the presence of anions and
810:
Ultrapure water is easily contaminated by traces of carbon dioxide from the atmosphere passing through tiny leaks or diffusing through thin wall polymer tubing when sample lines are used for measurement. Carbon dioxide forms conductive carbonic acid in water. For this reason, conductivity probes are
321:
were invented in 1935 and then became commercialized in the 1940s. The earliest "deionized" water systems relied on IX treatment to produce "high-purity" as determined by resistivity or conductivity measurements. After commercial RO membranes emerged in the 1960s, RO use with IX treatment eventually
277:
While each industry uses what it calls "ultrapure water", the quality standards vary, meaning that the UPW used by a pharmaceutical plant is different from that used in a semiconductor fab or a power station. The standards are based on the application. For instance, semiconductor plants use UPW as a
222:
equipment in the electrical power generation industry, and result in either short or long-term failure of electronic components in semiconductor chips and photovoltaic cells. Its sources are similar to those of TOC's. Depending on the level of purity needed, detection of these contaminants can range
1719:
The polishing stage is a set of treatment steps and is usually a recirculation and distribution system, continuously treating and recirculating the purified water to maintain a stable, high-purity quality of supplied water. Traditionally the resistivity of water serves as an indication of the level
1688:
Conventional butt fusion (CBF) is a process where the two components to be joined have the same inner and outer diameters. The ends are heated by pressing them against the opposite sides of a heater plate for a prescribed period of time. Then the two components are brought together. Upon cooling
1527:
that are later turned into computer chips. The ultrapure water is by definition extremely low in contamination, but once it makes contact with the wafer surface it carries residual chemicals or particles from the surface that then end up in the industrial waste treatment system of the manufacturing
1225:
Grab sample UPW analyses are either complementary to the on-line testing or alternative, depending on the availability of the instruments and the level of the UPW quality specifications. Grab sample analysis is typically performed for the following parameters: metals, anions, ammonium, silica (both
926:
to create droplets of UPW suspended in a stream of air. These droplets are dried at a high temperature to produce an aerosol of non-volatile residue particles. A measurement device called a condensation particle counter then counts the residue particles to give a reading in parts per trillion (ppt)
195:
processes that define nanometer-sized features. In other industries, their effects can range from a nuisance to life-threatening defects. Particles can be controlled by filtration and ultrafiltration. Sources can include bacterial fragments, the sloughing of the component walls within the conduit's
1531:
As noted above, ultrapure water is commonly not recycled in semiconductor applications, but rather reclaimed in other processes. There is one company in the US, Exergy
Systems, Inc. of Irvine, California, that offers a patented deionized water recycling process. This product has been successfully
1248:
Although particles and TOC are usually measured using on-line methods, there is significant value in complementary or alternative off-line lab analysis. The value of the lab analysis has two aspects: cost and speciation. Smaller UPW facilities that cannot afford to purchase on-line instrumentation
1506:
Available proprietary POU advanced oxidation processes can consistently reduce TOC to 0.5 parts per billion (ppb) in addition to maintaining consistent temperature, oxygen and particles exceeding the SEMI F063 requirements. This is important because the slightest variation can directly affect the
1385:
Capacity plays an important role in the engineering decisions about UPW system configuration and sizing. For example, polish systems of older and smaller size electronic systems were designed for minimum flow velocity criteria of up to 60 cm (2 ft) per second at the end of pipe to avoid bacterial
1320:
Primary treatment consists of ultraviolet light (UV) for organic reduction, EDI and or mixed bed ion exchange for demineralization. The mixed beds may be non-regenerable (following EDI), in-situ or externally regenerated. The last step in this section may be dissolved oxygen removal utilizing the
1290:
Some systems use direct return, reverse return or serpentine loops that return the water to a storage area, providing continuous re-circulation, while others are single-use systems that run from point of UPW production to point of use. The constant re-circulation action in the former continuously
1252:
Similar to TOC, SEM particle analysis represents a lower cost alternative to the expensive online measurements and therefore it is commonly a method of choice in less critical applications. SEM analysis can provide particle counting for particle size down to 50 nm, which generally is in-line
783:
Ultrapure water validation must utilize a risk-based lifecycle approach. This approach consists of three stages – design and development, qualification, and continued verification. One should utilize current regulatory guidance to comply with regulatory expectations. Typical guidance documents to
361:
stage. Impurities which can cause product contamination or impact process efficiency (e.g. etch rate) must be removed from the water during cleaning and etching stage. In chemical-mechanical polishing processes, water is used in addition to reagents and abrasive particles. As of 2002 1-2 parts of
1615:
A water management plan will also require a significant amount of sample data and analysis to determine proper drain segregation, application of online analytical measurement, diversions control, and final treatment technology. Collecting these samples and performing laboratory analysis can help
1467:
for lithography is the immersion water used at the lens/wafer interface for 193 nm immersion lithography patterning. The UPW forms a puddle between the lens and the wafer, improving NA, and the UPW must be extremely pure. POU filtration is used on the UPW just prior to the stepper scanner.
1411:
Particle levels must be controlled to nm sizes, and current trends are approaching 10 nm and smaller for particle control in UPW. While filters are used for the main loop, components of the UPW system can contribute additional particle contamination into the water, and at the point of use,
1244:
Silica analysis in UPW typically includes determination of reactive and total silica. Due to the complexity of silica chemistry, the form of silica measured is defined by the photometric (colorimetric) method as molybdate-reactive silica. Those forms of silica that are molybdate-reactive include
1236:
The anion analysis for seven most common inorganic anions (sulfate, chloride, fluoride, phosphate, nitrite, nitrate, and bromide) is performed by ion chromatography (IC), reaching single digit ppt detection limits. IC is also used to analyze ammonia and other metal cations. However ICPMS is the
823:
On-line sodium measurement in ultrapure water most commonly uses a glass membrane sodium ion-selective electrode and a reference electrode in an analyzer measuring a small continuously flowing side-stream sample. The voltage measured between the electrodes is proportional to the logarithm of the
806:
per centimeter (μS/cm), typical of the pharmaceutical and power industries or in resistivity units of megohm-centimeters (MΩ⋅cm) used in the microelectronics industries. These units are reciprocals of each other. Absolutely pure water has a conductivity of 0.05501 μS/cm and a resistivity of
1458:
For wet etch and clean, most tools are single wafer processes, which require flow through the filter upon tool demand. The resultant intermittent flow, which will range from full flow through the filter upon initiation of UPW flow through the spray nozzle, and then back to a trickle flow. The
1450:
Filters can be cartridge formats where the UPW is flowed through the pleated structure with contaminants collected directly on the filter surface. Common in UPW systems are ultrafilters (UF), composed of hollow fiber membranes. In this configuration, the UPW is flowed across the hollow fiber,
1407:
Particles in UPW are critical contaminants, which result in numerous forms of defects on wafer surfaces. With the large volume of UPW, which comes into contact with each wafer, particle deposition on the wafer readily occurs. Once deposited, the particles are not easily removed from the wafer
1684:
Socket fusion (SF) is a process where the outside diameter of the pipe uses a "close fit" match to the inner diameter of a fitting. Both pipe and fitting are heated on a bushing (outer and inner, respectively) for a prescribed period of time. Then the pipe is pressed into the fitting. Upon
1611:
plan. A successful water management plan includes full understanding of how the rinse waters are used in the manufacturing process including chemicals used and their byproducts. With the development of this critical component, a drain collection system can be designed to segregate concentrated
1598:
costs in parts of the US and Asia have pushed some semiconductor companies to investigate the recycling of manufacturing process rinse water in the UPW makeup system. Some companies have incorporated an approach that uses complex large scale treatment designed for worst case conditions of the
1313:
for suspended solids removal and turbidity reduction and
Activated Carbon for the reduction of organics. The Activated Carbon may also be used for removal of chlorine upstream of the reverse osmosis of demineralization steps. If activated carbon is not employed then sodium bisulfite is used to
174:
Bacteria have been referred to as one of the most obstinate in this list to control. Techniques that help to minimize bacterial colony growth within UPW streams include occasional chemical or steam sanitization (which is common in the pharmaceutical industry), ultrafiltration (found in some
1294:
For modern UPW systems it is important to consider specific site and process requirements such as environmental constraints (e.g., wastewater discharge limits) and reclaim opportunities (e.g., is there a mandated minimum amount of reclaim required). UPW systems consist of three subsystems:
847:
or optical fluorescence. Traditional electrochemical measurement uses a sensor with a gas-permeable membrane. Behind the membrane, electrodes immersed in an electrolyte develop an electric current directly proportional to the oxygen partial pressure of the sample. The signal is temperature
894:
Silica is measured on side stream samples with colorimetric analyzers. The measurement adds reagents including a molybdate compound and a reducing agent to produce a blue silico-molybdate complex color which is detected optically and is related to concentration according to the
1612:
chemicals from moderately contaminated rinse waters, and lightly contaminated rinse waters. Once segregated into separate collection systems the once considered chemical process waste streams can be repurposed or sold as a product stream, and the rinse waters can be reclaimed.
990:. Robust oxidation methods that supply sufficient oxygen include the following methods; Ultraviolet light (UV) & persulfate, heated persulfate, combustion, and super critical oxidation. Typical equations showing persulfate generation of hydroxyl radicals follows.
1359:
Maintain minimum scouring velocities in the piping and distribution network to ensure turbulent flow. The recommended minimum is based on a
Reynolds number of 3,000 Re or higher. This can range up to 10,000 Re depending on the comfort level of the designer.
183:
criteria for minimum flow, along with minimization of dead legs. In modern and advanced UPW systems, positive (higher than zero) bacteria counts are typically observed on newly constructed facilities. This issue is effectively addressed by sanitization using ozone or
1408:
surfaces. With the increased use of dilute chemistries, particles in UPW are an issue not only with UPW rinse of the wafers, but also due to introduction of the particles during dilute wet cleans and etch, where UPW is a major constituent of the chemistry used.
155:, particles, organic, and inorganic sources of contamination vary depending on a number of factors, including the feed water to make UPW, as well as the selection of the piping materials used to convey it. Bacteria are typically reported in colony-forming units (
1233:). The detection level depends on the specific type of the instrument used and the method of the sample preparation and handling. Current state-of-the-art methods allow reaching sub-ppt (parts per trillion) level (< 1 ppt) typically tested by ICPMS.
1415:
The filters themselves must be constructed of ultraclean and robust materials, which do not contribute organics or cations/anions into the UPW, and must be integrity tested out of the factory to assure reliability and performance. Common materials include
1454:
Point of use applications (POU) for UPW filtration include wet etch and clean, rinse prior to IPA vapor or liquid dry, as well as lithography dispense UPW rinse following develop. These applications pose specific challenges for POU UPW filtration.
1487:
and Mask preparation in order to maintain consistent ultrapure water quality. UPW systems located in the central utilities building provide the Fab with quality water but may not provide adequate water purification consistency for these processes.
1447:. In the former case the pore distribution is uniform through the filter, while in the latter the finer surface provides the particle removal, with the coarser structure giving physical support as well reducing the overall differential pressure.
132:
The most widely used requirements for UPW quality are documented by ASTM D5127 "Standard Guide for Ultra-Pure Water Used in the
Electronics and Semiconductor Industries" and SEMI F63 "Guide for ultrapure water used in semiconductor processing".
1390:
management and process optimization. As a result, newer UPW systems look rather alike, which is in contrast with smaller UPW systems that could have less optimized design due to the lower impact of inefficiency on cost and space management.
2320:
Huber S. A., Balz A, Abert M., and Pronk W. (2011) Characterisation of Aquatic Humic and Non-humic Matter with Size-Exclusion Chromatography - Organic Carbon Detection - Organic Nitrogen Detection (LC-OCD-OND). Water Research 4 5 (2 011)
42:
that has been purified to uncommonly stringent specifications. Ultrapure water is a term commonly used in manufacturing to emphasize the fact that the water is treated to the highest levels of purity for all contaminant types, including:
2042:"FDA/ICH, (CDER and CBER), Q8(R2) Pharmaceutical Development, guidance for industry, November 2009; Q9 Quality Risk Management, guidance for industry, June 2006; Q10 Pharmaceutical Quality System, guidance for industry, April 2009"
1352:
Select materials that will not contribute TOC and particles to the system particularly in the primary and polishing sections. Minimize stainless steel material in the polishing loop and, if used, electropolishing is recommended.
1222:
the majority of analytical tests. The point of connection (POC) is another commonly used point for measuring quality of UPW. It is located at the outlet of the submain or lateral take off valve used for UPW supply to the tool.
886:
and carry over with steam where it can form deposits on turbine blades which lower aerodynamic efficiency. Silica deposits are very difficult to remove. Silica is the first readily measurable species to be released by a spent
2450:
Sixsmith T, Wermelinger J, Williamson C and Burkhart M, "Advantages of Infra-Red Welding of Polyethylene Pipes for Industrial Applications", presented at the Plastic Pipes Conference XV, Vancouver, Canada, September 20–22,
1643:
remains a piping material of choice for the pharmaceutical industry. Due to its metallic contribution, most steel was removed from microelectronics UPW systems in the 1980s and replaced with high performance polymers of
629:
In order to be used for pharmaceutical and biotechnology applications for production of licensed human and veterinary health care products it must comply with the specification of the following pharmacopeias monographs:
316:
Early on, softened water produced by technologies like zeolite softening or cold lime softening was a precursor to modern UPW treatment. From there, the term "deionized" water was the next advancement as synthetic
1470:
For POU UPW applications, sub 15 nm filters are currently in use for advanced 2x and 1x nodes. The filters are commonly made of nylon, high-density polyethylene (HDPE), polyarylsulfone (or polysulfone), or
2078:"Gorsky, I., Lifecycle Approach to Validation of Water Systems, NEXUS Magazine of Southern California PDA chapter and its affiliate student chapter at the Keck Graduate Institute, Vol. I, Issue 1, April 2014"
289:(EDI) are the primary deionization technologies associated with UPW production, in most cases following reverse osmosis (RO). Depending on the required water quality, UPW treatment plants often also feature
2352:
Standard Test Methods for Microbiological Monitoring of Water Used for Processing Electron and Microelectronic Devices by Direct Pressure Tap Sampling Valve and by the Presterilized Plastic Bag Method
802:
In pure water systems, electrolytic conductivity or resistivity measurement is the most common indicator of ionic contamination. The same basic measurement is read out in either conductivity units of
1697:
uses pressure. The use of overlap in the former reduces the variation seen in bead size, meaning that precise dimensional tolerances needed for industrial installations can be maintained better.
1899:"Rowe RC, Sheskey PJ, Owen SC (eds), Pharmaceutical Excipients. Pharmaceutical Press and American Pharmacists Association. Electronic version, (MedicinesComplete Browser version 3.0.2624.26119"
1599:
combined waste water discharge. More recently new approaches have been developed to incorporate a detailed water management plan to try to minimize the treatment system cost and complexity.
2265:
Lee, Albert; Yang, Vincent; Hsu, Jones; Wu, Eva; Shih, Ronan. "Ultratrace measurement of calcium in ultrapure water using the Agilent 8800 Triple Quadrupole ICP-MS". Agilent Technologies.
1349:
Consider EDI and non-regenerable primary mixed beds in lieu of in-situ or externally regenerated primary beds to assure optimum quality UPW makeup and minimize the potential for upset.
2423:
922:
a significant loss in yield. To detect trace amounts of dissolved inorganic material a measurement of non-volatile residue is commonly used. This technique involves using a
74:
are not the same. In addition to the fact that UPW has organic particles and dissolved gases removed, a typical UPW system has three stages: a pretreatment stage to produce
1237:
preferred method for metals due to lower detection limits and its ability to detect both dissolved and non-dissolved metals in UPW. IC is also used for the detection of
1432:. Filters will commonly be constructed of a combination of polymers, and for UPW use are thermally welded without using adhesives or other contaminating additives.
2331:
Huber, Stefan; Libman, Slava (May–June 2014). "Part 1: Overview of LC-OCD: Organic Speciation in Service of Critical Analytical Tasks of Semiconductor Industry".
855:
and an optical detector. The fluorophore is immersed in the sample. Light is directed at the fluorophore which absorbs energy and then re-emits light at a longer
2255:
Standard Test Method for On-Line Monitoring of Total Carbon, Inorganic Carbon in Water by Ultraviolet, Persulfate Oxidation, and Membrane Conductivity Detection.
2176:"Pharmaceutical Inspection Convention Pharmaceutical Inspection Co-Operation Scheme (PIC/S), PI 009-3, 25-September 2007, Aide-Memoire, Inspection of Utilities"
1295:
pretreatment, primary, and polishing. Most systems are similar in design but may vary in the pretreatment section depending on the nature of the source water.
188:. With proper design of the polishing and distribution system, no positive bacteria counts are typically detected throughout the life cycle of the UPW system.
1230:
459:
240:
2154:
1065:
When the organic concentration is less than 1 mg/L as TOC and the water is saturated with oxygen UV light is sufficient to oxidize the organics to CO
1729:
If in-line conductivity exceeds values additional testing is required before a conclusion can be made. Refer to the respective pharmacopoeia for details.
863:. The signal is temperature compensated for the solubility of oxygen in water and the fluorophore characteristics to obtain the DO concentration value.
654:
Ultrapure water is often used as a critical utility for cleaning applications (as required). It is also used to generate clean steam for sterilization.
1343:
Steady state flow in the makeup and primary sections to avoid TOC and conductivity spikes (NO start/stop operation). Recirculate excess flow upstream.
2481:
2060:"ASTM E2500-07 Standard Guide for Specification, Design, and Verification of Pharmaceutical and Biopharmaceutical Manufacturing Systems and Equipment"
2175:
878:
processing and must be maintained at sub-ppb levels. In steam power generation silica can form deposits on heat-exchange surfaces where it reduces
2095:
310:
274:
The term "ultrapure water" became popular in the late 1970s and early 1980s to describe the particular quality of water used by these industries.
1495:(IPA) or other difficult to remove (low molecular weight neutral compounds) TOC species may be present, additional treatment is required thru
1989:
982:
There are multiple methods to create sufficient concentrations of hydroxyl radicals needed to completely oxidize the organics in water to CO
2434:
891:
and is therefore used as the trigger for anion resin regeneration. Silica is non-conductive and therefore not detectable by conductivity.
1241:
in UPW down to the 0.5 ppb level. Urea is one of the more common contaminants in UPW and probably the most difficult for treatment.
1624:
1270:
848:
compensated for the oxygen solubility in water, the electrochemical cell output and the diffusion rate of oxygen through the membrane.
302:
1934:
1226:
dissolved and total), particles by SEM (scanning electron microscope), TOC (total organic compounds) and specific organic compounds.
2407:
2119:
1787:
1377:
98:
199:
Total organic carbon in ultra pure water can contribute to bacterial proliferation by providing nutrients, can substitute as a
1799:
Mittlemann MW and Geesey GC,"Biofouling of Industrial Water Systems: A Problem Solving Approach", Water Micro Associates, 1987
346:, or as make-up to cooling fluid in some critical applications. UPW is even sometimes used as a humidification source for the
322:
became common. EDI was commercialized in the 1980s and this technology has now become commonly associated with UPW treatment.
1849:
1665:
236:
860:
362:
contaminating molecules per one million of water ones was considered to be an "ultrapure water" (e.g. semiconductor grade).
2024:"Gorsky, I., Validating Purified Water Systems with a Lifecycle Approach, UltraPure Water Journal, November/December, 2013"
1821:
1291:
polishes the water with every pass. The latter can be prone to contamination build up if it is left stagnant with no use.
2100:
1523:
The semiconductor industry uses a large amount of ultrapure water to rinse contaminants from the surface of the silicon
966:(IC) both together are defined as Total Carbon or TC. The TOC value is then equal to the difference between TC and IC.
110:
78:, a primary stage to further purify the water, and a polishing stage, the most expensive part of the treatment process.
1808:
Libman S, "Use of Reynolds Number as a Criteria for Design of High-Purity Water Systems", Ultrapure Water, October 2006
1515:
385:
224:
141:
2059:
1496:
1366:
Supply UPW to manufacturing at constant flow and constant pressure to avoid system upsets such as particle bursts.
681:
354:
118:
2041:
568:
A typical use of ultrapure water in pharmaceutical and biotechnology industries is summarized in the table below:
203:
for another chemical species in a sensitive thermal process, react in unwanted ways with biochemical reactions in
2204:
ASTM D5391 Standard Test Method for Electrical Conductivity and Resistivity of a Flowing High Purity Water Sample
1608:
2299:
Standard Test Method for Low-Level Total Silica in High-Purity Water by Flameless Atomic Absorption Spectroscopy
2161:
2023:
1576:
for non-process applications such as chemical aspirators where the discharge water is sent to industrial waste.
1369:
Utilize reverse return distribution loop design for hydraulic balance and to avoid backflow (return to supply).
859:. The duration and intensity of the re-emitted light is related to the dissolved oxygen partial pressure by the
2471:
649:
Note: Purified Water is typically a main monograph which references other applications that use Ultrapure water
81:
A number of organizations and groups develop and publish standards associated with the production of UPW. For
1916:
1657:
1645:
1472:
2182:
1632:
770:
672:
331:
122:
52:
657:
The following table summarizes the specifications of two major pharmacopoeias for 'water for injection':
560:; the cleanliness requirements in the semiconductor industry, however, are currently the most stringent.
2476:
2105:
1484:
126:
2379:
1952:
896:
2009:(USP38–NF33 ed.). Rockville, MD, USA: U.S. Pharmacopeial Convention. October 2014. p. 5805.
1436:
935:
844:
703:
538:
398:
306:
251:
Ultrapure water is treated through multiple steps to meet the quality standards for different users.
160:
1279:
ultraviolet (UV) light for TOC and/or bacterial static control, polishing by ion exchange resins or
342:
after application of chemicals, to dilute the chemicals themselves, in optics systems for immersion
1524:
1500:
1280:
728:
721:
530:
520:
286:
156:
1503:
and UV oxidation (refer to the persulfate+UV oxidation chemistry in the TOC measurement section).
2077:
1661:
888:
879:
534:
485:
318:
232:
168:
94:
48:
2120:"The EMEA CPMP/CVMP Note for Guidance on Quality of Water for Pharmaceutical Use (London, 2002)"
2403:
2270:
2222:
ASTM D5462 Standard Test Method for On-Line Measurement of Low-Level Dissolved Oxygen in Water
1985:
1898:
1577:
1492:
837:
358:
196:
wetted stream, and the cleanliness of the jointing processes used to build the piping system.
192:
185:
1439:
structure of the filter is critical in providing particle control, and this structure can be
1394:
designed with no use of chemicals and lower water and energy efficiency than larger systems.
909:
875:
343:
137:
82:
44:
1938:
2283:
2243:
Standard Method for On-Line Measurement of residue After Evaporation of High Purity Water.
1649:
1640:
1573:
1310:
1306:
1284:
871:
836:
Advanced microelectronics manufacturing processes require low single digit to 10 ppb
825:
542:
298:
294:
228:
191:
Particles in UPW are the bane of the semiconductor industry, causing defects in sensitive
180:
71:
2096:"FDA Guide to Inspections of High Purity Water Systems, High Purity Water Systems 07/93)"
1767:
Standard Guide for Ultra-Pure Water Used in the Electronics and Semiconductor Industries
2466:
1429:
1322:
1302:
803:
290:
75:
2460:
2195:
ASTM D1125 Standard Test Methods for Electrical Conductivity and Resistivity of Water
1669:
1607:
The key to maximizing water reclaim, recycle, and reuse is having a well thought out
557:
550:
529:
It is used in other types of electronics manufacturing in a similar fashion, such as
353:
The primary, and most critical, application of UPW is in wafer cleaning in and after
339:
215:
204:
114:
90:
64:
1421:
1363:
Use only virgin resin in the polishing mixed beds. Replace every one to two years.
282:
1857:
1356:
Minimize dead legs in the piping to avoid the potential for bacteria propagation.
1340:
Remove contaminants as far forward in the system as practical and cost effective.
1738:
One USP Endotoxin Unit (EU) is equal to one International Unit (IU) of endotoxin
1548:
1463:
1425:
852:
56:
1984:(8 ed.). Strasbourg, France: Council of Europe. 2013. pp. 3555–3558.
2362:
2231:
ASTM D7126 Standard Test Method for On-Line Colorimetric Measurement of Silica
1825:
1595:
1483:
Point of use treatment is often applied in critical tool applications such as
883:
856:
546:
60:
2363:"Saving Energy, Water, and Money with Efficient Water Treatment Technologies"
85:
and power, they include Semiconductor Equipment and Materials International (
2213:
ASTM D2791 Standard Test Method for On-line Determination of Sodium in Water
1444:
1440:
954:
amount into "mass of carbon" per volume concentration units. The initial CO
923:
347:
219:
211:
176:
2063:
2027:
1274:
Typical ultrapure water purification configuration in a semiconductor plant
2349:
2296:
2252:
2240:
1764:
623:
Water for the bulk preparation of medicines for parenteral administration
572:
Uses of ultrapure water in the pharmaceutical and biotechnology industries
2308:
152:
2155:"WHO Annex 2: Good manufacturing practice: water for pharmaceutical use"
554:
200:
164:
2393:
2391:
2389:
938:
is most commonly measured by oxidizing the organics in the water to CO
2424:"Vanox POU System for Point-of-Use Ultrapure Water Treatment Systems"
1874:
1475:(PTFE) membranes, with hardware typically consisting of HDPE or PFA.
179:, and optimization of piping system designs that promote the use of
1680:
Thermoplastics can be joined by different thermofusion techniques.
1346:
Minimize the use of chemicals following the reverse osmosis units.
1920:
1653:
1631:
1623:
1591:
1514:
1417:
1376:
1269:
769:
106:
39:
1507:
manufacturing process, significantly influencing product yields.
958:
in the water sample is defined as Inorganic Carbon or IC. The CO
1238:
553:
and image processors/ wafer-level optics (WLO), and crystalline
313:, particles, pH, and specialty measurements for specific ions).
210:
Metallic and anionic contamination in UPW systems can shut down
102:
86:
107:
International Association for the Properties of Water and Steam
2137:"USP Monograph <1231> Water For Pharmaceutical Purposes"
2007:
United States Pharmacopeia and the National Formulary (USP-NF)
2136:
1875:"Pdf - Semiconductor Technology from A to Z - Halbleiter.org"
1080:
O + hν (185 nm) → OH• + H • and H • + H • → H
365:
Water quality standards for use in the semiconductor industry
159:) per volume of UPW. Particles use number per volume of UPW.
1672:(PP) are popular, along with the high performance polymers.
1519:
Outline for a typical water system in a semiconductor plant
1790:
Guide for Ultrapure Water Used in Semiconductor Processing
1676:
Methods of joining thermoplastics used for UPW transport
1572:
Some semiconductor manufacturing plants have been using
1381:
Relationship between ultrapure water flow and wafer size
843:
Dissolved oxygen is measured by two basic technologies:
95:
American Society for Testing and Materials International
2082:
Parenteral Drug Association Southern California Chapter
824:
sodium ion activity or concentration, according to the
1966:
962:
produced from the oxidized organics and any initial CO
175:
pharmaceutical, but mostly semiconductor industries),
1336:
Key UPW design criteria for semiconductor fabrication
851:
Optical fluorescent DO sensors use a light source, a
643:
The United States Pharmacopoeia (USP): Purified water
270:
specialty applications such as research laboratories.
16:
Water purified to uncommonly stringent specifications
1816:
1814:
1685:
cooling the welded parts are removed from the clamp.
661:
Pharmacopoeia specifications for water for injection
591:
Diluent for ophthalmic and multiple-dose injections
167:
contaminants are measured in dimensionless terms of
2380:"High Efficiency reverse osmosis (HERO) technology"
1854:
International Technology Roadmap for Semiconductors
338:The use of UPW varies; it may be used to rinse the
1229:Metal analyses are typically performed by ICP-MS (
615:Diluent for internal irrigation therapy products
267:power generation (sub and super critical boilers)
1628:Various thermoplastic pipes used in UPW systems.
640:European Pharmacopoeia (Ph Eur): Aqua purificata
2141:United States Pharmacopeial Convention web site
1532:tested at a number of semiconductor processes.
979:utilize hydroxyl radicals in the liquid phase.
113:follow water quality standards as developed by
1305:. Typical pretreatments employed are two pass
779:Ultrapure water and deionized water validation
774:Ultrapure water system validation process flow
2046:The International Conference on Harmonisation
946:concentration after the oxidation or delta CO
97:(ASTM International) (semiconductor, power),
51:compounds; dissolved and particulate matter;
8:
1760:
1758:
1756:
1754:
1689:the welded parts are removed from the clamp.
1540:The following definitions are used by ITRS:
1266:UPW system design for semiconductor industry
1231:Inductively coupled plasma mass spectrometry
241:inductively coupled plasma mass spectrometry
1511:UPW recycling in the semiconductor industry
882:. In high temperature boilers, silica will
637:Japanese Pharmacopoeia (JP): Purified water
2018:
2016:
1783:
1781:
1779:
1777:
1775:
1773:
970:Organic oxidation methods for TOC analysis
665:
634:British Pharmacopoeia (BP): Purified water
576:
368:
1479:Point of use (POU) treatment for organics
258:semiconductor devices fabrication process
2311:Standard Test Method for Silica in Water
1129:TC (Total Carbon) = Organic Carbon + IC
874:is a contaminant that is detrimental to
599:Diluent for inhalation therapy products
103:American Society of Mechanical Engineers
2382:. Aquatech International. 9 April 2014.
2005:"USP Monographs: Water for Injection".
1967:"The United States Pharmacopoeia (USP)"
1750:
1712:
1660:(PTFE) in the US and Europe. In Asia,
1551:in the same application after treatment
564:Applications in pharmaceutical industry
2279:
2268:
1844:
1842:
1412:additional filtration is recommended.
1139:O + hν (185 nm) → OH• + H •
950:, and converting the measured delta CO
326:Applications in semiconductor industry
254:The primary industries using UPW are:
2402:. Littleton, CO: Tall Oaks Pub, Inc.
1636:A UPW installation using PVDF piping.
1132:TOC (Total Organic Carbon) = TC – IC
545:platters (HDD) and solid-state drive
305:, and measurement instruments (e.g.,
7:
2398:Dey, Avijit; Thomas, Gareth (2003).
2368:. Federal Energy Management Program.
1869:
1867:
1087:Different types of UPW TOC Analyzers
2400:Electronics grade water preparation
1563:– Extracting water from wastewater
1325:process or vacuum degasification.
942:, measuring the increase in the CO
588:Bacteriostatic water for injection
171:, such as ppm, ppb, ppt, and ppq.
163:(TOC), metallic contaminants, and
117:, of which three examples are the
14:
1953:"European Pharmacopoeia (Ph Eur)"
1850:"ITRS Annual Report 2013 Edition"
1283:(EDI), and finally filtration or
788:Analytical methods and techniques
136:Ultra pure water is also used as
99:Electric Power Research Institute
2482:Semiconductor device fabrication
1654:ethylene chlorotrifluoroethylene
793:On-line analytical measurements
330:UPW is used extensively in the
70:UPW and the commonly used term
1666:chlorinated polyvinyl chloride
1557:– Use in secondary application
1314:de-chlorinate the feed water.
237:atomic absorption spectroscopy
1:
1935:"Japanese Pharmacopoeia (JP)"
404:(on-line for <10 ppb)
2101:Food and Drug Administration
1917:"British Pharmacopoeia (BP)"
1491:In the case when urea, THM,
1162:+ hν (254 nm) → 2
1013:+ hν (254 nm) → 2
620:Water for injections in bulk
612:Sterile water for irrigation
596:Sterile water for inhalation
1903:Current version of the book
974:Oxidation of organics to CO
604:Sterile water for injection
495:7 major Anions and ammonium
225:conductivity (electrolytic)
2498:
1568:Water reclaim and recycle:
1497:advanced oxidation process
1073:. The equations follow:
498:(see F63-0213 for details)
472:(see F63-0213 for details)
335:usually produced on-site.
227:readings to sophisticated
119:United States Pharmacopeia
2431:Evoqua Water Technologies
861:Stern–Volmer relationship
692:Conductivity (25 °C)
53:volatile and non-volatile
1980:"Water for injections".
1091:IC (Inorganic Carbon) =
798:Conductivity/resistivity
414:On-line dissolved oxygen
311:resistivity/conductivity
89:) (microelectronics and
2333:Ultrapure Water Journal
1658:polytetrafluoroethylene
1646:polyvinylidene fluoride
1473:polytetrafluoroethylene
1373:Capacity considerations
910:laser particle counters
607:Diluent for injections
469:22 most common elements
303:ultraviolet irradiation
55:; reactive, and inert;
2108:on September 26, 2012.
1982:European Pharmacopoeia
1941:on September 11, 2014.
1860:on September 21, 2014.
1637:
1629:
1603:Water management plan:
1520:
1382:
1301:Pretreatment produces
1275:
775:
332:semiconductor industry
2066:on February 12, 2014.
1635:
1627:
1518:
1485:Immersion lithography
1380:
1273:
773:
447:(total and dissolved)
127:Japanese Pharmacopeia
123:European Pharmacopeia
111:Pharmaceutical plants
32:highly purified water
2440:on October 26, 2014.
1261:Purification process
1217:Offline lab analysis
936:Total organic carbon
917:Non-volatile residue
889:anion exchange resin
845:electrochemical cell
717:Bacteria (guideline)
704:Total Organic Carbon
435:Non-Volatile Residue
429:<200 particles/L
399:Total Organic Carbon
307:total organic carbon
161:Total organic carbon
105:(ASME) (power), and
72:deionized (DI) water
1501:ammonium persulfate
1398:Critical UPW issues
1281:electrodeionization
535:discrete components
531:flat panel displays
476:<1–10 ng/L
287:electrodeionization
261:solar photovoltaics
212:enzymatic processes
148:Sources and control
2185:on March 27, 2014.
1879:www.halbleiter.org
1662:polyvinyl chloride
1638:
1630:
1521:
1383:
1276:
880:thermal efficiency
776:
712:<0.5 mg/L
426:(>0.05 μm)
233:ion chromatography
169:parts per notation
2278:Missing or empty
2164:on April 7, 2014.
1991:978-92-871-7531-1
1578:Water reclamation
1493:isopropyl alcohol
1403:Particles control
768:
767:
709:<0.5 mg/L
651:
627:
626:
527:
526:
499:
473:
424:On-line particles
405:
193:photolithographic
186:hydrogen peroxide
109:(IAPWS) (power).
28:high-purity water
2489:
2452:
2448:
2442:
2441:
2439:
2433:. Archived from
2428:
2420:
2414:
2413:
2395:
2384:
2383:
2376:
2370:
2369:
2367:
2359:
2353:
2347:
2341:
2340:
2328:
2322:
2318:
2312:
2306:
2300:
2294:
2288:
2287:
2281:
2276:
2274:
2266:
2262:
2256:
2250:
2244:
2238:
2232:
2229:
2223:
2220:
2214:
2211:
2205:
2202:
2196:
2193:
2187:
2186:
2181:. Archived from
2180:
2172:
2166:
2165:
2160:. Archived from
2159:
2151:
2145:
2144:
2133:
2127:
2126:
2124:
2116:
2110:
2109:
2104:. Archived from
2092:
2086:
2085:
2074:
2068:
2067:
2062:. Archived from
2056:
2050:
2049:
2038:
2032:
2031:
2026:. Archived from
2020:
2011:
2010:
2002:
1996:
1995:
1977:
1971:
1970:
1963:
1957:
1956:
1949:
1943:
1942:
1937:. Archived from
1931:
1925:
1924:
1919:. Archived from
1913:
1907:
1906:
1895:
1889:
1888:
1886:
1885:
1871:
1862:
1861:
1856:. Archived from
1846:
1837:
1836:
1834:
1833:
1824:. Archived from
1822:"UltrapureMicro"
1818:
1809:
1806:
1800:
1797:
1791:
1785:
1768:
1762:
1739:
1736:
1730:
1727:
1721:
1717:
1609:water management
1212:
1211:
1210:
1200:
1198:
1197:
1187:
1186:
1185:
1173:
1172:
1171:
1161:
1160:
1159:
1151:
1150:
1126:
1125:
1124:
1114:
1113:
1112:
1102:
1101:
1100:
1061:
1060:
1059:
1049:
1047:
1046:
1036:
1035:
1034:
1024:
1023:
1022:
1012:
1011:
1010:
1002:
1001:
897:Beer–Lambert law
876:microelectronics
838:dissolved oxygen
832:Dissolved oxygen
742:<0.25 EU/mL
666:
647:
577:
497:
471:
408:<1 μg/L
403:
392:>18.18 MΩ·cm
369:
357:step during the
344:photolithography
138:boiler feedwater
101:(EPRI) (power),
83:microelectronics
2497:
2496:
2492:
2491:
2490:
2488:
2487:
2486:
2472:Water treatment
2457:
2456:
2455:
2449:
2445:
2437:
2426:
2422:
2421:
2417:
2410:
2397:
2396:
2387:
2378:
2377:
2373:
2365:
2361:
2360:
2356:
2348:
2344:
2330:
2329:
2325:
2319:
2315:
2307:
2303:
2295:
2291:
2277:
2267:
2264:
2263:
2259:
2253:ASTM D5997 - 96
2251:
2247:
2239:
2235:
2230:
2226:
2221:
2217:
2212:
2208:
2203:
2199:
2194:
2190:
2178:
2174:
2173:
2169:
2157:
2153:
2152:
2148:
2135:
2134:
2130:
2122:
2118:
2117:
2113:
2094:
2093:
2089:
2076:
2075:
2071:
2058:
2057:
2053:
2040:
2039:
2035:
2022:
2021:
2014:
2004:
2003:
1999:
1992:
1979:
1978:
1974:
1965:
1964:
1960:
1951:
1950:
1946:
1933:
1932:
1928:
1915:
1914:
1910:
1897:
1896:
1892:
1883:
1881:
1873:
1872:
1865:
1848:
1847:
1840:
1831:
1829:
1820:
1819:
1812:
1807:
1803:
1798:
1794:
1786:
1771:
1763:
1752:
1748:
1743:
1742:
1737:
1733:
1728:
1724:
1718:
1714:
1709:
1704:
1678:
1650:perfluoroalkoxy
1641:Stainless steel
1622:
1574:reclaimed water
1513:
1481:
1405:
1400:
1375:
1338:
1311:ultrafiltration
1307:reverse osmosis
1285:ultrafiltration
1268:
1263:
1219:
1209:
1206:
1205:
1204:
1202:
1196:
1193:
1192:
1191:
1189:
1184:
1181:
1180:
1179:
1177:
1170:
1167:
1166:
1165:
1163:
1158:
1155:
1154:
1153:
1149:
1146:
1145:
1144:
1142:
1138:
1123:
1120:
1119:
1118:
1116:
1111:
1108:
1107:
1106:
1104:
1099:
1096:
1095:
1094:
1092:
1083:
1079:
1072:
1068:
1058:
1055:
1054:
1053:
1051:
1045:
1042:
1041:
1040:
1038:
1033:
1030:
1029:
1028:
1026:
1021:
1018:
1017:
1016:
1014:
1009:
1006:
1005:
1004:
1000:
997:
996:
995:
993:
989:
985:
977:
972:
965:
961:
957:
953:
949:
945:
941:
933:
919:
905:
869:
834:
826:Nernst equation
817:
800:
795:
790:
685:
683:
676:
674:
663:
574:
566:
543:hard disk drive
508:Microbiological
496:
470:
402:
378:
376:
366:
328:
299:ultrafiltration
295:microfiltration
264:pharmaceuticals
249:
229:instrumentation
181:Reynolds Number
150:
65:dissolved gases
20:Ultrapure water
17:
12:
11:
5:
2495:
2493:
2485:
2484:
2479:
2474:
2469:
2459:
2458:
2454:
2453:
2443:
2415:
2408:
2385:
2371:
2354:
2342:
2323:
2313:
2301:
2289:
2257:
2245:
2233:
2224:
2215:
2206:
2197:
2188:
2167:
2146:
2128:
2111:
2087:
2069:
2051:
2033:
2030:on 2014-09-17.
2012:
1997:
1990:
1972:
1958:
1944:
1926:
1923:on 2014-09-26.
1908:
1890:
1863:
1838:
1810:
1801:
1792:
1769:
1749:
1747:
1744:
1741:
1740:
1731:
1722:
1711:
1710:
1708:
1705:
1703:
1700:
1699:
1698:
1694:
1690:
1686:
1677:
1674:
1621:
1618:
1585:UPW recycling:
1565:
1564:
1558:
1552:
1512:
1509:
1480:
1477:
1430:fluoropolymers
1404:
1401:
1399:
1396:
1374:
1371:
1337:
1334:
1323:degasification
1303:purified water
1267:
1264:
1262:
1259:
1218:
1215:
1207:
1194:
1182:
1168:
1156:
1147:
1136:
1121:
1109:
1097:
1081:
1077:
1070:
1066:
1056:
1043:
1031:
1019:
1007:
998:
987:
983:
975:
971:
968:
963:
959:
955:
951:
947:
943:
939:
932:
929:
918:
915:
904:
901:
868:
865:
833:
830:
816:
813:
799:
796:
794:
791:
789:
786:
766:
765:
762:
759:
755:
754:
751:
748:
744:
743:
740:
739:<0.25 IU/mL
737:
733:
732:
725:
718:
714:
713:
710:
707:
700:
699:
698:<1.3 μS/cm
696:
693:
689:
688:
679:
670:
645:
644:
641:
638:
635:
625:
624:
621:
617:
616:
613:
609:
608:
605:
601:
600:
597:
593:
592:
589:
585:
584:
581:
565:
562:
525:
524:
517:
513:
512:
510:
504:
503:
500:
492:
491:
489:
478:
477:
474:
466:
465:
463:
452:
451:
448:
441:
440:
439:100 ng/L
437:
431:
430:
427:
420:
419:
416:
410:
409:
406:
394:
393:
390:
381:
380:
373:
372:Test Parameter
327:
324:
291:degasification
272:
271:
268:
265:
262:
259:
248:
245:
149:
146:
76:purified water
15:
13:
10:
9:
6:
4:
3:
2:
2494:
2483:
2480:
2478:
2475:
2473:
2470:
2468:
2465:
2464:
2462:
2447:
2444:
2436:
2432:
2425:
2419:
2416:
2411:
2409:0-927188-10-4
2405:
2401:
2394:
2392:
2390:
2386:
2381:
2375:
2372:
2364:
2358:
2355:
2351:
2346:
2343:
2338:
2334:
2327:
2324:
2317:
2314:
2310:
2305:
2302:
2298:
2293:
2290:
2285:
2272:
2261:
2258:
2254:
2249:
2246:
2242:
2237:
2234:
2228:
2225:
2219:
2216:
2210:
2207:
2201:
2198:
2192:
2189:
2184:
2177:
2171:
2168:
2163:
2156:
2150:
2147:
2142:
2138:
2132:
2129:
2121:
2115:
2112:
2107:
2103:
2102:
2097:
2091:
2088:
2083:
2079:
2073:
2070:
2065:
2061:
2055:
2052:
2047:
2043:
2037:
2034:
2029:
2025:
2019:
2017:
2013:
2008:
2001:
1998:
1993:
1987:
1983:
1976:
1973:
1968:
1962:
1959:
1954:
1948:
1945:
1940:
1936:
1930:
1927:
1922:
1918:
1912:
1909:
1904:
1900:
1894:
1891:
1880:
1876:
1870:
1868:
1864:
1859:
1855:
1851:
1845:
1843:
1839:
1828:on 2018-12-16
1827:
1823:
1817:
1815:
1811:
1805:
1802:
1796:
1793:
1789:
1784:
1782:
1780:
1778:
1776:
1774:
1770:
1766:
1761:
1759:
1757:
1755:
1751:
1745:
1735:
1732:
1726:
1723:
1716:
1713:
1706:
1701:
1695:
1691:
1687:
1683:
1682:
1681:
1675:
1673:
1671:
1670:polypropylene
1667:
1663:
1659:
1655:
1651:
1647:
1642:
1634:
1626:
1619:
1617:
1613:
1610:
1605:
1604:
1600:
1597:
1593:
1587:
1586:
1582:
1579:
1575:
1570:
1569:
1562:
1561:Water Reclaim
1559:
1556:
1553:
1550:
1546:
1543:
1542:
1541:
1538:
1537:
1533:
1529:
1526:
1517:
1510:
1508:
1504:
1502:
1498:
1494:
1489:
1486:
1478:
1476:
1474:
1468:
1465:
1460:
1456:
1452:
1448:
1446:
1442:
1438:
1433:
1431:
1427:
1423:
1419:
1413:
1409:
1402:
1397:
1395:
1391:
1387:
1379:
1372:
1370:
1367:
1364:
1361:
1357:
1354:
1350:
1347:
1344:
1341:
1335:
1333:
1330:
1326:
1324:
1319:
1315:
1312:
1308:
1304:
1300:
1299:Pretreatment:
1296:
1292:
1288:
1286:
1282:
1272:
1265:
1260:
1258:
1254:
1250:
1246:
1242:
1240:
1234:
1232:
1227:
1223:
1216:
1214:
1175:
1140:
1133:
1130:
1127:
1089:
1088:
1084:
1074:
1063:
991:
980:
969:
967:
937:
930:
928:
925:
916:
914:
911:
902:
900:
898:
892:
890:
885:
881:
877:
873:
866:
864:
862:
858:
854:
849:
846:
841:
839:
831:
829:
827:
821:
814:
812:
808:
805:
797:
792:
787:
785:
781:
780:
772:
763:
760:
757:
756:
752:
749:
746:
745:
741:
738:
735:
734:
730:
726:
723:
719:
716:
715:
711:
708:
705:
702:
701:
697:
695:<1.3 μS/cm
694:
691:
690:
687:
682:United States
680:
678:
675:Pharmacopoeia
671:
668:
667:
664:
662:
658:
655:
652:
650:
642:
639:
636:
633:
632:
631:
622:
619:
618:
614:
611:
610:
606:
603:
602:
598:
595:
594:
590:
587:
586:
582:
579:
578:
575:
573:
569:
563:
561:
559:
558:photovoltaics
556:
552:
551:image sensors
548:
544:
540:
536:
532:
522:
518:
515:
514:
511:
509:
506:
505:
502:50 ng/L
501:
494:
493:
490:
487:
483:
480:
479:
475:
468:
467:
464:
461:
457:
454:
453:
450:50 ng/L
449:
446:
443:
442:
438:
436:
433:
432:
428:
425:
422:
421:
418:10 μg/L
417:
415:
412:
411:
407:
401:
400:
396:
395:
391:
388:
387:
383:
382:
377:Semiconductor
374:
371:
370:
367:
363:
360:
356:
351:
350:environment.
349:
345:
341:
336:
333:
325:
323:
320:
314:
312:
308:
304:
300:
296:
292:
288:
284:
279:
275:
269:
266:
263:
260:
257:
256:
255:
252:
246:
244:
242:
238:
234:
230:
226:
221:
217:
216:bioprocessing
213:
208:
206:
205:bioprocessing
202:
197:
194:
189:
187:
182:
178:
172:
170:
166:
162:
158:
154:
147:
145:
143:
139:
134:
130:
128:
124:
120:
116:
115:pharmacopeias
112:
108:
104:
100:
96:
92:
88:
84:
79:
77:
73:
68:
66:
62:
58:
54:
50:
46:
41:
37:
33:
29:
25:
21:
2477:Liquid water
2446:
2435:the original
2430:
2418:
2399:
2374:
2357:
2345:
2336:
2332:
2326:
2316:
2304:
2292:
2260:
2248:
2236:
2227:
2218:
2209:
2200:
2191:
2183:the original
2170:
2162:the original
2149:
2140:
2131:
2114:
2106:the original
2099:
2090:
2081:
2072:
2064:the original
2054:
2045:
2036:
2028:the original
2006:
2000:
1981:
1975:
1961:
1947:
1939:the original
1929:
1921:the original
1911:
1902:
1893:
1882:. Retrieved
1878:
1858:the original
1853:
1830:. Retrieved
1826:the original
1804:
1795:
1734:
1725:
1715:
1679:
1656:(ECTFE) and
1639:
1614:
1606:
1602:
1601:
1588:
1584:
1583:
1571:
1567:
1566:
1560:
1554:
1544:
1539:
1536:Definitions:
1535:
1534:
1530:
1522:
1505:
1490:
1482:
1469:
1461:
1457:
1453:
1449:
1434:
1422:polyethylene
1414:
1410:
1406:
1392:
1388:
1384:
1368:
1365:
1362:
1358:
1355:
1351:
1348:
1345:
1342:
1339:
1328:
1327:
1317:
1316:
1298:
1297:
1293:
1289:
1277:
1255:
1251:
1247:
1243:
1235:
1228:
1224:
1220:
1176:
1141:
1134:
1131:
1128:
1090:
1086:
1085:
1075:
1064:
992:
981:
973:
934:
920:
906:
893:
870:
850:
842:
835:
822:
818:
809:
804:microsiemens
801:
782:
778:
777:
684:Pharmacopeia
660:
659:
656:
653:
648:
646:
628:
571:
570:
567:
528:
507:
481:
456:Metals/Boron
455:
444:
434:
423:
413:
397:
389:(25 °C)
384:
364:
352:
337:
329:
315:
283:ion exchange
280:
276:
273:
253:
250:
247:Applications
223:from simple
209:
198:
190:
173:
151:
135:
131:
91:photovoltaic
80:
69:
35:
31:
27:
23:
19:
18:
2339:(3): 10–16.
1668:(CPVC) and
1555:Water Reuse
1549:Water reuse
1545:UPW Recycle
1464:lithography
1437:microporous
1426:polysulfone
927:by weight.
853:fluorophore
750:<0.2 ppm
669:Properties
386:Resistivity
355:wet etching
61:hydrophobic
57:hydrophilic
2461:Categories
2350:ASTM F1094
2297:ASTM D4517
2280:|url=
2241:ASTM D5544
1884:2022-06-14
1832:2018-12-12
1765:ASTM D5127
1746:References
1702:References
1596:wastewater
1445:asymmetric
1329:Polishing:
1025:• and
884:volatilize
857:wavelength
761:<10 ppb
677:(Ph. Eur.)
547:NAND flash
243:(ICP-MS).
140:in the UK
2309:ASTM D859
1620:Transport
1441:isotropic
1321:membrane
924:nebulizer
903:Particles
758:Aluminium
736:Endotoxin
537:(such as
348:cleanroom
319:IX resins
285:(IX) and
239:(AA) and
177:ozonation
49:inorganic
2321:879-885.
2271:cite web
1788:SEMI F63
1648:(PVDF),
1318:Primary:
747:Nitrates
731:/100 mL
673:European
523:/100 mL
516:Bacteria
375:Advanced
231:such as
153:Bacteria
1664:(PVC),
1652:(PFA),
1213:+ OH •
1062:+ OH •
727:<10
724:/100 mL
720:<10
555:silicon
549:(SSD),
281:Today,
220:corrode
201:carbide
165:anionic
144:fleet.
45:organic
2406:
1988:
1525:wafers
1428:, and
872:Silica
867:Silica
815:Sodium
519:<1
460:ICP/MS
445:Silica
235:(IC),
125:, and
63:; and
2467:Water
2438:(PDF)
2427:(PDF)
2366:(PDF)
2179:(PDF)
2158:(PDF)
2123:(PDF)
1707:Notes
1592:water
1418:nylon
706:(TOC)
686:(USP)
340:wafer
40:water
38:) is
2451:2010
2404:ISBN
2284:help
1986:ISBN
1594:and
1462:For
1435:The
1239:urea
1201:→
1188:• +
1050:→
1037:• +
764:N/A
753:N/A
583:Use
580:Type
539:LEDs
484:(by
482:Ions
458:(by
379:UPW
359:FEOL
87:SEMI
59:and
47:and
1443:or
1203:HSO
1105:HCO
1052:HSO
931:TOC
729:CFU
722:CFU
541:),
521:CFU
214:in
157:CFU
142:AGR
93:),
36:HPW
30:or
26:),
24:UPW
2463::
2429:.
2388:^
2337:31
2335:.
2275::
2273:}}
2269:{{
2139:.
2098:.
2080:.
2044:.
2015:^
1901:.
1877:.
1866:^
1852:.
1841:^
1813:^
1772:^
1753:^
1547:–
1424:,
1420:,
1287:.
1178:SO
1174:•
1164:SO
1117:CO
1115:+
1103:+
1093:CO
1027:SO
1015:SO
533:,
486:IC
309:,
301:,
297:,
293:,
218:,
129:.
121:,
67:.
2412:.
2286:)
2282:(
2143:.
2125:.
2084:.
2048:.
1994:.
1969:.
1955:.
1905:.
1887:.
1835:.
1208:4
1199:O
1195:2
1190:H
1183:4
1169:4
1157:8
1152:O
1148:2
1143:S
1137:2
1135:H
1122:3
1110:3
1098:2
1082:2
1078:2
1076:H
1071:2
1067:2
1057:4
1048:O
1044:2
1039:H
1032:4
1020:4
1008:8
1003:O
999:2
994:S
988:2
984:2
976:2
964:2
960:2
956:2
952:2
948:2
944:2
940:2
488:)
462:)
34:(
22:(
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.