Background Statement for SEMI Draft Document #4547E REVISION TO SEMI C , SPECIFICATIONS FOR n-methyl 2- PYRROLIDONE

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1 Background Statement for SEMI Draft Document #4547E REVISION TO SEMI C , SPECIFICATIONS FOR n-methyl 2- PYRROLIDONE Notice: This background statement is not part of the balloted item. It is provided solely to assist the recipient in reaching an informed decision based on the rationale of the activity that preceded the creation of this Document. Notice: Recipients of this Document are invited to submit, with their comments, notification of any relevant patented technology or copyrighted items of which they are aware and to provide supporting documentation. In this context, patented technology is defined as technology for which a patent has issued or has been applied for. In the latter case, only publicly available information on the contents of the patent application is to be provided. Background: C33 is overdue for 5-year review. As a result of the review process, this ballot proposes minor changes for consistency with other SEMI Standards on liquid chemicals. These changes are marked by strikethrough for deletions and underlines for additions. Review and Adjudication Information Task Force Review Committee Adjudication Group: Analytical Methods TF NA Liquid Chemicals Committee Date: Monday, October 29, 2012 Tuesday, October 30, 2012 Time & Timezone: 10:00 AM to 12:00 Noon, Pacific Time 1:00 PM to 4:00 PM, Pacific Time Location: SEMI Headquarters SEMI Headquarters City, State/Country: San Jose, California San Jose, California Leader(s): Frank Flowers (FMC)/ Frank.Flowers@fmc.com Frank Flowers (FMC)/ Frank.Flowers@fmc.com Frank Parker (ICL)/ Standards Staff: Michael Tran (SEMI NA) mtran@semi.org Frank.Parker@icl-pplp.com Michael Tran (SEMI NA) mtran@semi.org This meeting s details are subject to change, and additional review sessions may be scheduled if necessary. Contact the task force leaders or Standards staff for confirmation. Telephone and web information will be distributed to interested parties as the meeting date approaches. If you will not be able to attend these meetings in person, but would like to participate by telephone/web, please contact Standards staff. Notice: Additions are indicated by underline and deletions are indicated by strikethrough.

2 SEMI Draft Document #4547E REVISION TO SEMI C , SPECIFICATIONS FOR n-methyl 2- PYRROLIDONE 1 Purpose These specifications were technically approved by the Global Process Chemicals Committee and are the direct responsibility of the North American Process Chemicals Committee. Current edition approved by the North American Regional Standards Committee on October 17, Initially available at February 2001; to be published March This document replaces SEMI C1.25, C7.16, and C8.11 in their entirety. Originally published in 1986, 1992, and 1998 respectively; previously published June The purpose of this standarddocument is to standardize requirements for n-methyl 2-pyrrolidone used in the semiconductor industry and testing procedures to support those standards specifications. Test methods have been shown to give statistically valid results. Alternative methods may be used as long as they comply with SEMI C1 requirements for method validation.this document also provides guidelines for grades of n-methyl 2-pyrrolidone for which a need has been identified. In the case of the guidelines, the test methods may not have been statistically validated yet. 2 Scope 2.1 The scope of this standarddocument is all grades of n-methyl 2-pyrrolidone used in the semiconductor industry. NOTICE: SEMI Standards and Safety Guidelines do not purport to address all safety issues associated with their use. It is the responsibility of the users of the Documents to establish appropriate safety and health practices, and determine the applicability of regulatory or other limitations prior to use. NOTICE: This standard does not purport to address safety issues, if any, associated with its use. It is the responsibility of the users of this standard to establish appropriate safety and health practices and determine the applicability of regulatory or other limitations prior to use. 3 Limitations 3.1 None. 4 Referenced Standards and Documents 4.1 SEMI Standards SEMI C1 Guide for the Analysis of Liquid Chemicals Specifications for Reagents 4.2 ASTM Standards 1 ASTM D5127 Standard Guide for Ultra Pure Water Used in the Electronics and Semiconductor Industry NOTICE: Unless otherwise indicated, all documents cited shall be the latest published versions. R1-1 As listed or revised, all documents cited shall be the latest publications of adopted standards. 5 Terminology 5.1 None. 6 Physical Propertiesy (for information only) 1 American Society for Testing and Materials, 100 Barr Harbor Drive, West Conshohocken, Pennsylvania , USA. Telephone: ; Fax: ; Page 1 Doc. 4547E SEMI

3 Table 1 Properties of n-methyl 2-Pyrrolidone Chemical Formula CH 3 N(CH 2 ) 3 CO CAS Number Density at 25 C 1.03 g/ml Density at 25C 1.03 g/ml 6 7 Requirements The requirements for n-methyl 2-pyrrolidone for Grades 1, 2, and 3 are listed in Table Grade 1 Procedures 7.1 Due to the uncertainty of acid concentration in the liquid residue, the final concentration can be estimated to be approximately 2% (v/v). NOTE 1: Alternative methods may be used as long as they comply with SEMI C1 requirements for method validation. 7.2 Each laboratory is responsible for verifying the validity of the method within its own operation Assay Analyze the sample by gas chromatography (see SEMI C1, in Section Section 3.1, Guidelines for Assay by Wide Bore Column Gas Chromatography ). The parameters cited have given satisfactory results. Column: micron I.D. fused silica capillary, coated with 5 micron film of DB-1 or equivalent (100% methyl silicone which has been surface bonded and cross linked). Table 2 Chromatography Conditions Column Temperature: Injector Temperature: Detector Temperature: Sample Size: Carrier Gas: Detector: 100C isothermal 250C 300C 0.2 L splitless Helium at 5 ml/min Thermal Conductivity Approximate Retention Times (min): Butyrolactone Methyl 2-Pyrrolidone 20.2 Methyl Homologue 21.2 Methyl Homologue Color Dilute 10.0 ml of platinum-cobalt stock solution (APHA No. 500) with water. Compare this standard (APHA No. 50) with 100 ml of sample in Nessler tubes. View vertically over a white background. The sample must be no darker than the standard. 8.3 Water Add 25 ml of methanol to a dry titration flask and add Karl Fischer (KF) reagent to a visually or electrometrically determined endpoint that persists for 30 seconds. Add 98 ml (100 g) of sample, taking care to protect the sample and contents of the flask from moisture. Stir vigorously and titrate with Karl Fischer reagent to the same endpoint. Page 2 Doc. 4547E SEMI

4 % gh 2O ml KF reagent KF factor 100 ml Water (H2O) (1) Mass of Sample (g) Free Amines Weigh 63 ml (65 g) of sample into a 500 ml beaker. Add 100 ml of 2-propanol and mix thoroughly. Into the solution, insert a ph and reference electrodes connected to a ph meter set to the direct voltage mode. Titrate potentiometrically with 0.05 N hydrochloric acid in 2-propanol. Express the result in terms of methylamine: % Free Amines as CH 3 NH 2 ml N of HCl 3.10 Weight of sample g Volume of HCl (ml) Normality of HCl3.10 % Free Amines as (CH3NH2) (2) Massof Sample (g) Chloride In a 50 ml glass-stoppered graduated cylinder, dilute 24.5 ml (25 g) of sample with water to volume. Place a 10 ml aliquot of this solution into a 50 ml Nessler tube and a 30 ml aliquot into a second tube. To the first tube add 0.01 mg of chloride standard and mix. Dilute the contents of each tube to about 45 ml with water, mix, add 1 ml of nitric acid and 1 ml of silver nitrate reagent solution (see SEMI C1), mix thoroughly, and allow to stand for 10 minutes. Any turbidity produced by the sample shouldshall be no greater than that of the 0.01 mg standard Phosphate Add 20 ml (20g) of sample to 100 ml of dilute ammonium hydroxide (1 + 4). Prepare a standard containing 0.1 mg of phosphate ion (PO 4 ) in 100 ml of dilute ammonium hydroxide. Proceed as follows with each of the two solutions Add, while stirring vigorously, 3.5 ml of a 10% solution of ferric nitrate 9-hydrate. Allow to stand for 15 minutes. If the precipitate has not coagulated by this time, warm gently (avoid boiling). Filter and wash the precipitate on the filter with several portions of quite dilute ammonium hydroxide (1 + 9). Discard the filtrate and washings. Dissolve the precipitate on the filter with 50 ml nitric acid (1 + 3) added in small portions. Catch the filtrate in a 250 ml glass-stoppered conical flask. Add 13 ml of ammonium hydroxide (28% 32% NH 3 ) to the flask while swirling and continue agitation until any precipitate redissolves. Warm the solution to 40C and add 50 ml of ammonium molybdate-nitric acid reagent solution ( ). Shake vigorously for 5 minutes and allow to stand at 40C for 2 hours. The precipitate, if any, for the sample shouldshall be no greater than that for the standard Ammonium Molybdate-Nitric Acid Reagent Solution Mix thoroughly 100 g of molybdate acid, 85%, with 240 ml of water and 140 ml of ammonium hydroxide (28% 32% NH 3 ). Filter and add 60 ml of nitric acid. Cool and while stirring continually, pour into a cooled mixture of 400 ml of nitric acid and 960 ml of water. Add 0.1 g of ammonium phosphate, monobasic, NH 4 H 2 PO 4, allow to stand 24 hours and filter through glass wool Arsenic and Antimony (as As) Evaporate 20 ml (20 g) of sample in a 150 ml beaker to a small volume on a hot plate. Cool, add carefully 15 ml of nitric acid and 5 ml of sulfuric acid, and evaporate to dense fumes of sulfur trioxide. Add 10 ml of nitric acid and again evaporate to dense fumes. If carbon is still present, cool, add 1 ml of 30% hydrogen peroxide, and evaporate to dense fumes of sulfur trioxide. Repeat this step with hydrogen peroxide addition until carbon has been removed completely. Cool, and cautiously wash the colorless residue into a generator flask with water to make a volume of 35 ml. Proceed as described in SEMI C1 in Section Trace Arsenic (and Antimony) Determination, the General Method for Arsenic (and Antimony) under SEMI C1, Section 3.4.5, starting with the sentence that begins Swirl the flask... Any red color in the silver diethyldithiocarbamate solution of the sample shouldshall be no greater than that of the standard containing mg of arsenic (As) Trace Metal Analysis The following method has given satisfactory results in determining trace metal impurities at the value specified for each of the following trace metals: aluminum (Al), antimony (Sb), arsenic (As), barium (Ba), boron (B), cadmium (Cd), calcium (Ca), chromium (Cr), copper (Cu), gold (Au), iron (Fe), lead (Pb), lithium (Li), magnesium (Mg), manganese (Mn), nickel (Ni), potassium (K), sodium (Na), tin (Sn), titanium (Ti), vanadium (V), and zinc (Zn). Alternate methods may be used as long as they comply with SEMI C1 requirements Page 3 Doc. 4547E SEMI

5 for method validation.appropriate studies demonstrate recovery between % of a known sample spike for half of the value of each specified item Special Reagents Hydrochloric Acid, Ultra Pure Use hydrochloric acid with metal ion content less than 10 ppb for each element specified. specified for ultra low metal ion content Mannitol Powder Use mannitol specified for reagent grade (A.C.S.) and determined, via the reagent blank, to be ultra low metal ion content % Mannitol Solution Dissolve and dilute 5 g of mannitol to 100 ml using water meeting the criteria for Type E1.1 in ASTM D5127 in regard to metallic impurities % (v/v) Hydrochloric Acid Solution Dilute 20 ml of ultra pure, 12 M hydrochloric acid ( ) to 1 L using water meeting the criteria for Type E1.1 in ASTM D5127 in regard to metallic impurities Sample Preparation In a clean environment, place 250 g of samplesolvent in a PTFE dish. Add 0.5 ml of freshly prepared 5% mannitol solution. Slowly evaporate on a hot plate, avoiding loss of sample by effervescence or spattering until approximately 1 ml of liquid remains. Take up liquid and all visible residue (from walls of dish) with 1 ml ultra pure, 12 M hydrochloric acid ( ) and continue heating until approximately 0.5 ml of liquid remains. No undissolved particulate matter shouldshall be observed. Otherwise, repeat the addition of hydrochloric acid until all particulate matter is dissolved. Transfer quantitatively to a 50 ml volumetric flask using 2% (v/v) hydrochloric acid ( ) and adjust liquid level to mark. Prepare a reagent blank using the same reagents and in the same manner as for the sample concentration Analysis Using the prepared sample and reagent blank, analyze group 1 elements potassium (K) and sodium (Na) by atomic absorption spectroscopy and all other elements by plasma emission spectrometry (see SEMI C1). Apply, if necessary, a reagent blank correction to the final determined value of the sample. 8 9 Grade 2 Procedures Non-Metal Impurities See Section 8, which contains procedures for the following tests: Assay Free Amines Color (APHA) Water (H 2 O) 8.2 Methyl Amines The following method has given satisfactory results in determining methyl amine impurities at the values specified for each of the following methyl amines: mono-methylamine (MMA), di-methylamine (DMA), and trimethylamine (TMA). Alternative methods may be used as long as appropriate studies demonstrate a recovery between % of a known sample spike for half of the value of each specified element Special Reagents Eluent Prepare N hydrochloric (HCl) solution in deionized water meeting the criteria for Type E1.1 in ASTM D Regenerant Prepare a 0.1 M tetrabutyl-ammonium hydroxide (TBAOH) solution in deionized water meeting the criteria for Type E1.1 in ASTM D Sample Preparation Sample is injected neat Analysis Page 4 Doc. 4547E SEMI

6 Using the prepared solutions and blanks, analyze mono-methylamine, di-methylamine, and tri-methylamine by ion chromatography. Run a reagent blank. Samples and reagent blanks should be prepared and analyzed in triplicate Columns Precolumn should be CG2 (Dionex) or equivalent and separation column should be a CS2 (Dionex) or equivalent Anions The following method has given satisfactory results in determining various anions at the values specified for each of the following anions: chloride (Cl), nitrate (NO 3 ), phosphate (PO 4 ), and sulfate (SO 4 ). Alternate methods may be used as long as they comply with the SEMI C1 requirements for method validation.appropriate studies demonstrate a recovery between % of a known sample spike for half of the value of each specified anion Special Reagents Eluent Prepare a solution containing 0.38 g of sodium carbonate (Na 2 CO 3 ) and 0.29 g of sodium bicarbonate (NaHCO 3 ) in 2 liters of deionized water meeting the criteria for Type E1.1 in ASTM D Regenerant Deionized water meeting the criteria for Type E1.1 in ASTM D Sample Preparation ml of NMP is added to a 100 ml plastic volumetric flask and is filled to the mark using deionized water meeting the criteria for Type E1.1 in ASTM D Analysis Using the prepared solutions and blanks, analyze chloride, nitrate, phosphate, and sulfate by ion chromatography. Run a reagent blank. Samples and blanks shouldshall be prepared in triplicate Columns Precolumn shouldshall be AG3 (Dionex) or equivalent and the separation column shouldshall be AS3 (Dionex) or equivalent Trace Metals Analysis The following method has given satisfactory results in determining metal ion impurities at the values specified for each of the following metals: aluminum (Al), antimony (Sb), arsenic (As), barium (Ba), boron (B), cadmium (Cd), calcium (Ca), chromium (Cr), cobalt (Co), copper (Cu), gold (Au), iron (Fe), lead (Pb), lithium (Li), magnesium (Mg), manganese (Mn), nickel (Ni), potassium (K), silver (Ag), sodium (Na), strontium (Sr), tin (Sn), titanium (Ti), vanadium (V), and zinc (Zn). Alternate methods may be used as long as they comply with SEMI C1 requirements for method validation.appropriate studies demonstrate a recovery between % of a known sample spike for half of the value of each specified element Special Reagents Nitric Acid, Ultra Pure Use nitric acid with metal ion content less than 1 ppb for each element of interest. specified for low metal ion content Water The water used for all the dilution, calibration, and standards shouldshall meet, at a minimum, the criteria for Type E1.1 in ASTM D5127 in regard to cation analysis Indium Internal Standard Make up the indium internal standard solution to a concentration of 20 µg/ml (ppm) from the appropriate concentrated indium standard solution Sample Preparation Place sample (1 gram) in a quartz dish. Slowly evaporate to dryness (45 min. at 70 80C). Add 2 grams of concentrated nitric acid and heat for 15 minutes until approximately 1 gram remains. Remove the hotplate and add DI water to a final weight of 10 grams Analysis Using the prepared solution and blanks, analyze the elements by inductively coupled plasma mass spectrometry (ICP/MS). For calibration, the standards are made up with 1% nitric acid solution and the indium internal standard such that the final indium concentration is 20 ng/g. Page 5 Doc. 4547E SEMI

7 9 10 Grade 3 Procedures Non-Metal Impurities See Section 8, which contains procedures for the following tests: Assay Color (APHA) Water (H 2 O) Methyl Amines Free Amines Anions NOTE 2: For Anions, please see Methyl Amines The following method has given satisfactory results in determining methyl amine impurities at the values specified for each of the following methyl amines: mono-methylamine (MMA), dimethylamine (DMA), and trimethylamine (TMA). Alternative methods may be used as long as appropriate studies demonstrate a recovery between 75% 125% of a known sample spike for half of the value of each specified element. 9.3 Special Reagents Eluent Prepare N hydrochloric acid (HCl) solution in deionized water meeting the criteria for Type E1.1 in ASTM D Regenerant Prepare a 0.1 M tetrabutyl-ammonium hydroxide (TBAOH) solution in deionized water meeting the criteria for Type E1.1 in ASTM D Sample Preparation Sample is injected neat. 9.4 Analysis Using the prepared solutions and blanks, analyze mono-methylamine, di-methylamine, and tri-methylamine by ion chromatography. Run a reagent blank. Samples and reagent blanks should be prepared and analyzed in triplicate Columns Pre-column should be CG2 (Dionex) or equivalent and separation column should be a CS2 (Dionex) or equivalent. 9.5 Anions The following method has given satisfactory results in determining various anions at the values specified for each of the following anions: chloride (Cl), nitrate (NO 3 ) phosphate (PO 4 ) and sulfate (SO 4 ). Alternate methods may be used as long as appropriate studies demonstrate a recovery between % of a known sample spike for half of the value of each specified anion. 9.6 Special Reagents Eluent Prepare a solution containing 0.38 g of sodium carbonate (Na 2 CO 3 ) and 0.29 g of sodium bicarbonate (NaHCO 3 ) in 2 liters of deionized water meeting the criteria for Type E1.1 in ASTM D Regenerant Deionized water meeting the criteria for Type E1.1 in ASTM D Sample Preparation ml of NMP is added to a 100 ml plastic volumetric flask and is filled to the mark using deionized water meeting the criteria for Type E1.1 in ASTM D Analysis Using the prepared solutions and blanks, analyze chloride, nitrate, phosphate, and sulfate by ion chromatography. Run a reagent blank. Samples and blanks should be prepared in triplicate. Page 6 Doc. 4547E SEMI

8 9.8.2 Columns Pre-column should be AG3 (Dionex) or equivalent and the separation column should be AS3 (Dionex) or equivalent Trace Metal Analysis The following method has given satisfactory results in determining metal ion impurities at the values specified for each of the following metals: aluminum (Al), antimony (Sb), arsenic (As), barium (Ba), boron (B), cadmium (Cd), calcium (Ca), chromium (Cr), copper (Cu), gold (Au), iron (Fe), lead (Pb), lithium (Li), magnesium (Mg), manganese (Mn), nickel (Ni), potassium (K), sodium (Na), tin (Sn), titanium (Ti), vanadium (V), and zinc (Zn). Alternate methods may be used as long as they comply with SEMI C1 requirements for method validation. appropriate studies demonstrate a recovery between % of a known sample spike for half of the value of each specified element Special Reagents Nitric Acid, Ultra Pure Use nitric acid with metal ion content less than 0.1 ppb for each element of interest. specified for low metal ion content Water The water used for all the dilution, calibration, and standards shouldshall meet, at a minimum, the criteria for Type E1.1 in ASTM D5127 in regard to cation analysis Sample Preparation In a 100 ml volumetric, add 20 ml of sample and fill to the mark such that the final solution contains 2% nitric acid Standard Preparation Four standards are prepared such that the final solution contains 2% nitric acid (i.e., 2% of 70% nitric acid vol/vol) and 20% vol/vol sample. The four standards are 0.5, 1, 5, and 10 ppb Analysis This is a method of standard addition procedure. Using the prepared solutions, analyze the elements by inductively coupled plasma mass spectrometry (ICP/MS) Hot plasma conditions with shield are used for the following elements: Ti, Mn, Ni, Cu, Cd, As, Sb, Sn, Au, and Pb and V Cold plasma conditions with shield are used for the follow elements:, Ba, Li, B, Na, Mg, Al, K, Ca, Cr, Fe, and Zn Grade 4 Procedures This section does not apply to this chemical Grade 5 Procedures This section does not apply to this chemical. 12 VLSI Grade Procedures 12.1 This section does not apply to this chemical. 13 Tier A Procedures 13.1 This section does not apply to this chemical. 14 Tier B Procedures 14.1 This section does not apply to this chemical. 15 Tier C Procedures 15.1 This section does not apply to this chemical. Page 7 Doc. 4547E SEMI

9 16 Tier D Procedures 16.1 This section does not apply to this chemical. Table 3 Impurity Limits and Other Requirements for n-methyl 2-Pyrrolidone Previous SEMI Reference # SEMI C SEMI C SEMI C Assay #1 (see NOTE 1) (CH 3 N(CH 2 ) 3 CO) Grade 1 Grade 2 Grade 3 (Specification) (Specification) (Specification) 99.5% min. 99.8% min. 99.8% Color (APHA) 50 max. 50 max. 30 max. Water (H 2 O) 0.05% max. 0.05% max. 0.03% max. Free Amines (as CH 3 NH 2 ) 50 ppm max. 5 ppm5,000 ppb max. 5 ppm max. Chloride (Cl) 1 ppm max. 500 ppb max. 300 ppb max. Nitrate (NO 3 ) ppb max. 400 ppb max. Phosphate (PO 4 ) 5 ppm max. 500 ppb max. 250 ppb max. Sulfate (SO 4 ) ppb max. 250 ppb max. Aluminum (Al) 0.1 ppm max. 20 ppb max. 5 ppb max. Antimony (Sb) ppb max. 10 ppb max. Arsenic (As) ppb max. 10 ppb max. Arsenic and Antimony (as As) 0.1 ppm max Barium (Ba) Boron (B) 0.1 ppm max. 20 ppb max. 10 ppb max. Cadmium (Cd) ppb max. -- Calcium (Ca) ppb max. 5 ppb max. Chromium (Cr) 0.1 ppm max. 100 ppb max. 10 ppb max. Cobalt (Co) ppb max. -- Copper (Cu) 0.1 ppm max. 20 ppb max. 5 ppb max. Gold (Au) 0.1 ppm max. 20 ppb max. 5 ppb max. Iron (Fe) 0.1 ppm max. 20 ppb max. 10 ppb max. Lead (Pb) 0.1 ppm max. 20 ppb max. 5 ppb max. Lithium (Li) ppb max. -- Magnesium (Mg) 0.1 ppm max. 20 ppb max. 5 ppb max. Manganese (Mn) 0.1 ppm max. 100 ppb max. 5 ppb max. Nickel (Ni) 0.1 ppm max. 20 ppb max. 5 ppb max. Potassium (K) 0.1 ppm max. 20 ppb max. 5 ppb max. Silver (Ag) ppb max. -- Sodium (Na) 0.3 ppm max. 20 ppb max. 10 ppb max. Strontium (Sr) ppb max. -- Tin (Sn) 0.1 ppm max. 20 ppb max. 5 ppb max. Titanium (Ti) 0.1 ppm max. 20 ppb max. 5 ppb max. Vanadium (V) ppb max. -- Zinc (Zn) 0.1 ppm max. 100 ppb max. 10 ppb max. Particles in bottles: size, #/ml #2 1.0 m, 10 max. #2 0.5 m, 200 max. #2 0.5 m, 15 max. Page 8 Doc. 4547E SEMI

10 Table 3 Impurity Limits and Other Requirements for n-methyl 2-Pyrrolidone Previous SEMI Reference # SEMI C SEMI C SEMI C #1 Assay by gas chromatography includes 3- and 4-methyl homologs. Grade 1 Grade 2 Grade 3 (Specification) (Specification) (Specification) #2 Due to limitations of current particle counters, particle size and numbers are to be agreed upon between supplier and user. See SEMI C1 in Section Calibration and Measurement Method for Particles in Liquids. NOTICE: (SEMI) makes no warranties or representations as to the suitability of the Standards and Safety Guidelines set forth herein for any particular application. The determination of the suitability of the Standard or Safety Guideline is solely the responsibility of the user. Users are cautioned to refer to manufacturer s instructions, product labels, product data sheets, and other relevant literature, respecting any materials or equipment mentioned herein. Standards and Safety Guidelines are subject to change without notice. By publication of this Standard or Safety Guideline, SEMI takes no position respecting the validity of any patent rights or copyrights asserted in connection with any items mentioned in this Standard or Safety Guideline. Users of this Standard or Safety Guideline are expressly advised that determination of any such patent rights or copyrights, and the risk of infringement of such rights are entirely their own responsibility. Page 9 Doc. 4547E SEMI