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EP-4225479-B1 - FILTRATION MEMBRANE SYSTEMS, AND METHODS FOR PRODUCING PURIFIED WATER

EP4225479B1EP 4225479 B1EP4225479 B1EP 4225479B1EP-4225479-B1

Inventors

  • HAMZIK, JAMES
  • SAMPATH, SIDDARTH
  • BREWSTER, Justin
  • BHABHE, Ashutosh Shrikant

Dates

Publication Date
20260506
Application Date
20211001

Claims (12)

  1. A system useful for removing an impurity from a flow of source water, the system comprising: a composite polymeric filter membrane comprising: a porous polymeric base membrane with an amino polyol ligand having three or more hydroxyl groups attached to the polymeric base membrane, and a microporous polymeric filter membrane for removing particulates, and an ion-exchange resin.
  2. The system of claim 1, wherein: the amino polyol ligand is N-methyl-D-glucamine.
  3. The system of claim 1 or claim 2, wherein the polymeric base membrane comprises a polyolefin or a halogenated polymer.
  4. The system of any preceding claim, wherein the polymeric base membrane comprises polyethylene optionally ultra-high molecular weight polyethylene.
  5. The system of any preceding claim, wherein the porous polymeric base membrane has a pore size characterized by a bubble point in a range from 27579 Pa to 1.10316 MPa (4 psi to 160 psi), the bubble point measured using ethoxy-nonafluorobutane (HFE-7200) is used as the wetting solvent at a temperature of 22 °C.
  6. The system of any preceding claim, wherein the microporous polymeric filter membrane is free from said amino polyol ligand.
  7. The system of any preceding claim, wherein the microporous polymeric filter membrane has a bubble point in a range of about 6894.76 Pa to 0.689476 MPa (10 psi to 100 psi), the bubble point measured using ethoxy-nonafluorobutane (HFE 7200) as wetting agent at a temperature of 20-25°C.
  8. The system of any preceding claim, wherein: the system is configured so the flow of source water passes first through the ion exchange resin, and second through the composite polymeric filter membrane, or the system is configured so the flow of source water passes first through the composite polymeric filter membrane, and second through the ion exchange resin.
  9. A method of removing an impurity from a flow of source water, the method comprising flowing the source water through a polymeric filter membrane that comprises: a first porous polymeric base membrane, and amino polyol ligand having three or more hydroxyl groups attached to the polymeric base membrane, removing silica particles from the source water by passing the source water through a second porous polymeric filter membrane that is effective to remove silica particles, before or after passing the source water through the first polymeric filter membrane; and passing the flow of source water through an ion exchange resin before or after passing the flow of source water through the first polymeric filter membrane.
  10. The method of claim 9, wherein: the amino polyol ligand is N-methyl-D-glucamine, or the polymeric base membrane comprises polyethylene, or both.
  11. The method of any of claim 9 10, wherein the source water exhibits one or more of: resistivity: > 18.18 MΩ·cm, total organic carbon: < 1 µg/L, on-line dissolved oxygen: < 10 µg/L, bacteria: < 1 CFU/100 mL.
  12. The method of any of claims 9 through 11, wherein the impurity is dissolved metal or boron, and the method produces water having: an individual metal impurity concentration of 0.1 µg/L or below, a boron concentration of 0.1 µg/L or below, or both.

Description

FIELD The present disclosure relates to filter membranes, related filter assemblies and filtration systems, and related method useful for producing purified (e.g., ultrapure) water, including membranes, systems, and methods useful for preparing purified water that will be useable for processing (e.g., rinsing) semiconductor and microelectronic substrates, components, and devices. The present invention is as defined in the appended claims. BACKGROUND Highly pure water, including water sometimes referred to as "ultrapure" water ("UPW"), is important for a variety of commercial uses, including in semiconductor processing (e.g., manufacturing semiconductor devices, liquid crystal displays, silicon wafers, printed circuit boards, and other electronic and microelectronic devices), in the operation of nuclear power plants, and in pharmaceutical manufacturing. Purified water used in semiconductor processing is useful in semiconductor and microelectronic processing (as one example) as rinse water for cleaning or preparing of a surface of a semiconductor or microelectronic device substrate, e.g., as part of a "front-end" or "back end" process recipe. As uses, ultrapure water may be used in Wet Etch and Cleans ("WEC"), Photolithography and Chemical Mechanical Polishing ("CMP") of in-process microelectronic devices. The water must be of exceedingly high purity because impurities in water used to process a microelectronic device or semiconductor substrate, and that is left behind on a substrate surface, will affect the yield and short/long term performance of a resultant semiconductor or microelectronic device made from the substrate. Filtering systems for preparing ultrapure water must be effective to remove impurities (a.k.a. "contaminants") to a very high degree of purity, and, for the sake of manufacturing efficiency, must do so for an extended period of time minimizing the need for replacement of a filtration element. Removing and replacing a filtration element of a filtration system that supplies ultrapure water to semiconductor processing equipment can require the equipment to be shut down for a period of time required to remove and replace the filtration element, i.e., a "changeout" period. The changeout period is expensive in terms of lost time of use of the semiconductor processing equipment, which results in reduced processing efficiency and increased overall costs. The changeout frequency and period can affect the efficiency of equipment that directly uses the purified water and can also affect processes that are performed downstream of the directly affected equipment. Ultrapure water used in semiconductor processing is not completely pure but is understood to contain very low levels of contaminants that include silica particles (colloidal and hard SiO2 particles), organics (dissolved and undissolved), and dissolved metals or metal-containing compounds such as such boron, silicon (e.g., as SiO2), iron, and titanium. Boron and silica impurities are particularly problematic because current filtration systems are not sufficiently effective in removing and retaining boron and silica (e.g., colloidal and solid silica particles), or may be effective to remove these impurities from a flow of water for an operational lifetime that is not sufficiently lengthy. Common designs of ultrapure water production facilities include an ion-exchange (IEX) resin in the form of a bed of polymeric beads through which water is passed for removal of ions from the water. The polymeric resin beads attract and retain trace ionic impurities and remove the impurities from the water flowing through the bed of polymeric beads. With such ion-exchange systems, after an amount of time during which the system is used to remove boron, silicon (e.g., solid and colloidal silica particles, or dissolved silica), or both, from a water source, the capacity of an ion-exchange resin bed to remove and contain (retain) boron, silicon, or both, becomes exhausted. The ability of the ion-exchange system to continue to remove additional amounts of boron or silicon (silica) from water is depleted and it no longer removes boron or silicon from a flow of water. When this occurs, these impurities begin to pass through the ion-exchange system and "leak" from the system to downstream equipment as unwanted impurities. With ever increasing degrees of complexity in the integration of microelectronic devices, trace-level contaminants in ultrapure water become increasingly significant. Thus, ultrapure water having ever higher levels of purity is required to meet goals (economic and otherwise) related to wafer die yield and overall reliability of the semiconductor or microelectronic device. SUMMARY The following description relates to porous polymeric filter membranes that include a porous polymeric base membrane and amino polyol ligand that contains at least three hydroxyl groups ("the amino polyol" or "amino polyol ligand") attached to the base membrane. The descripti