Background Statement for SEMI Draft Document 5080B
REVISION OF SEMI F51-0200, GUIDE FOR ELASTOMETRIC SEALING
TECHNOLOGY
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.
NOTICE: This Document was completely rewritten. Per the Procedure Manual (March 2015) ¶3.5.1.1 a
complete rewrite is appropriate when the use of underline and strikethrough would be excessive.
Background
SEMI F51, Guide for Elastomeric Sealing Technology, is long overdue for its five year review. To provide
standards for o-rings and seals used in Semiconductor Process Equipment this method should be reviewed and
updated as necessary so that it can continue to be used for specifying sealing compounds and their applications.
Due to the myriad of different chemical and physical properties of both seals and processes updating the
standardized approach for specifying sealing compounds and seal configurations is needed. The mis-application
of o-rings and seals creates significant costs and downtime.
Sealing technology is an area continuing to play and ever increasing role in high yielding manufacturing
processes, yet the Microelectronic Industry’s sealing requirements are poorly defined. Complicating the issue is
that some seals used were developed for unrelated industries. Thus, the existing parameters that define good
sealing characteristics are very different than those required by microelectronics manufacturing; i.e.: cleanliness,
particulation seal life.
The ballot results will be reviewed and adjudicated at the meetings indicated in the table below. Check
www.semi.org/standards under Calendar of Events for the latest update.
Ballot Adjudication Information
Task Force Review
SEMI F51 (Perfluoroelastomer) Revision TF
Monday, July 13, 2015
12:30 – 14:00 Pacific Time (Tentative)
San Francisco Marriott Marquis Hotel in
conjunction with the NA Standards Meetings
at SEMICON West 2015
City, State/Country: San Francisco, California/USA
Dalia Vernikovsky (Applied Global Seal)
Leader(s):
Standards Staff:
Michael Tran
408.943.7019
mtran@semi.org
Group:
Date:
Time & Timezone:
Location:
Committee Adjudication
NA Facilities TC Chapter
Tuesday, July 14, 2015
9:00 – 12:00 Pacific Time
San Francisco Marriott Marquis Hotel in
conjunction with the NA Standards Meetings
at SEMICON West 2015
San Francisco, California/USA
Steve Lewis (DPS Engineering)
Michael Tran
408.943.7019
mtran@semi.org
Semiconductor Equipment and Materials International
3081 Zanker Road
San Jose, CA 95134-2127
Phone: 408.943.6900, Fax: 408.943.7943
DRAFT
SEMI Draft Document 5080B
REVISION OF SEMI F51-0200, GUIDE FOR ELASTOMETRIC SEALING
TECHNOLOGY
NOTICE: This Document was completely rewritten. Per the Procedure Manual (March 2015) ¶3.5.1.1 a complete
rewrite is appropriate when the use of underline and strikethrough would be excessive.
1 Purpose
1.1 This Document is a basic guide for the use of seals in semiconductor fabrication equipment. The document is also
an introduction of the diverse chemical and physical requirements for the many process applications and how choosing
appropriate sealing materials is helpful to reduce cost of ownership and to improve up-time. It is important that
equipment users, suppliers, OEMs, and seal manufacturers follow the same terminology so that communication can
take place with alignment when the actual performance of the equipment is being discussed.
2 Scope
2.1 This Guide is applicable to the use of seals in operating environments used in the fabrication of semiconductor
devices. O-rings were originally developed in 1896, for industrial markets and much later for aerospace, but were
never developed to meet semiconductor needs. Current ASTM standards do not specifically relate to semiconductor
seal performance. This guide will aid in defining the criteria by which sealing performance can be judged in
comparable measurements and seal materials can be chosen.
2.2 Seal performance in semiconductor equipment and components consists of but not limited to the specifications
shown in Table 1.
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.
Table 1 Relative importance of seal performance criteria in several applications/process areas.
(Rate 1-5, 1: most important; 5: least important)
Applications
/ Process areas
Wet Etch
Dry Etch
CVD / PVD
Diffusion
Sub-Fab
Seal Etch Rate
5
1
3
5
2
Sealing Force Retention
1
1
1
1
1
Leachable
1
5
5
5
3
Ash
5
1
1
1
2
Outgassing
5
2
1
3
5
Permeation
5
1
1
3
3
TOC
1
5
5
2
5
Properties
Specifications
Sealing Requirements
Impurities
This is a Draft Document of the SEMI International Standards program. No material on this page is to be construed as an official or adopted Standard or Safety Guideline.
Permission is granted to reproduce and/or distribute this document, in whole or in part, only within the scope of SEMI International Standards committee (document development)
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DRAFT
3 Limitations
3.1 The application of this Guide is limited to elastomeric seals that are used in semiconductor manufacturing and
related process equipment.
4 Referenced Standards and Documents
4.1 SEMI Standards
SEMI C3 — Specifications for Gases
SEMI D9 — Definitions for Flat Panel Display Substrates
SEMI E45 — Test Method for the Determination of Inorganic Contamination from minienvironments
SEMI E49 — Guide for High Purity and Ultrahigh Purity Piping Performance, Subassemblies, and final Assemblies.
SEMI F21 — Classification of Airborne Molecular Contaminant Levels in Clean Environments
SEMI F57 — Specification of Polymer Materials and Components used in Ultrapure Water and Liquid Chemical
Distribution Systems
SEMI F61 — Guide for Ultrapure Water Systems Used in Semiconductor Processing
SEMI F75 — Guide for Quality Monitoring of Ultrapure Water Used in Semiconductor
SEMI P5 — Specification for Pellicles
SEMI S4 — Safety Guideline for the Segregation/Separation of Gas Cylinders Contained in Cabinets
4.2 ASTM Standards1
ASTM D1414 — Standard Test Methods for Rubber O-Rings
ASTM D1415 — Standard Test Method for Rubber Property - International Hardness
ASTM D2000 — Standard Classification for Rubber Products in Automotive Application
ASTM D2240 — Standard Test Method for Rubber Property - Durometer Hardness
ASTM D395 — Standard Test Methods for Rubber Property - Compression Set
ASTM D412 — Standard Test Methods for Vulcanized Rubber and Thermoplastic Elastomers-Tension
ASTM D575 — Standard Test Methods for Rubber Properties in Compression
ASTM D5904 — Standard Test Method for Total Carbon, Inorganic Carbon, and Organic Carbon in Water by
Ultraviolet, Per sulfate Oxidation, and Membrane Conductivity Detection
ASTM D6317 — Standard Test Methods for Low Level Determination of Total Carbon; Inorganic Carbon and
Organic Carbon in Water by Ultraviolet, Per sulfate Oxidation, and Membrane Conductivity Detection.
4.3 IEST Standards2
IEST-RP-CC031.3 — Method for Characterizing Outgassed Organic Compounds from Cleanroom Materials and
Components
4.4 ISO Standards3
ISO 37 — Rubber, vulcanized or thermoplastic -- Determination of tensile stress-strain properties
1
ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, USA; Telephone: 610.832.9585, Fax: 610.832.9555,
http://www.astm.org
2
Institute of Enviornmental Sciences and Technology, IEST, Arlington Place One, 2340 S. Arlington Heights Road, Suite 620
Arlington Heights, IL 60005, Telephone: 847.981.0100, Fax: 847.981.4130, http://www.iest.org
3
International Organization for Standardization, ISO Central Secretariat, 1, ch. de la Voie-Creuse, CP 56, CH-1211 Geneva 20, Switzerland;
Telephone: 41.22.749.01.11, Fax: 41.22.733.34.30, http://www.iso.org
This is a Draft Document of the SEMI International Standards program. No material on this page is to be construed as an official or adopted Standard or Safety Guideline.
Permission is granted to reproduce and/or distribute this document, in whole or in part, only within the scope of SEMI International Standards committee (document development)
activity. All other reproduction and/or distribution without the prior written consent of SEMI is prohibited.
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ISO 48 — Rubber, vulcanized or thermoplastic -- Determination of hardness (hardness between 10 IRHD and 100
IRHD)
ISO 7619 — Rubber, vulcanized or thermoplastic -- Determination of indentation hardness -- Part 1: Durometer
Method (Shore hardness)
ISO 7743 — Rubber, vulcanized or thermoplastic -- Determination of compression stress-strain properties
ISO 815 — Rubber, vulcanized or thermoplastic -- Determination of compression set -- Part 1: At ambient or elevated
Temperatures
NOTICE: Unless otherwise indicated, all documents cited shall be the latest published versions.
5 Terminology
5.1 Abbreviations and Acronyms
5.1.1 Five and Four Letter Acronyms:
5.1.1.1 LPCVD — Low Pressure Chemical Vapor Deposition
5.1.1.2 MOCVD — Metal Organic Chemical Vapor Deposition
5.1.1.3 UPDI — Ultra Pure De-ionized
5.1.2 Three and Two Letter Acronyms:
5.1.2.1 ATM — Atmospheric
5.1.2.2 BCDS — Bulk Chemical Dispensing System
5.1.2.3 CVD — Chemical Vapor Deposition
5.1.2.4 HDP — High Density Plasma
5.1.2.5 OEM — Original Equipment Manufacturer
5.1.2.6 PPB — Parts per Billion
5.1.2.7 PVD — Physical Vapor Deposition
5.1.2.8 RTP — Rapid Thermal Process
5.1.2.9 TOC —Total Oxidizable (organic) Carbon
5.1.2.10 DI — Deionized
5.1.2.11 HF — Hydrofluoric Acid
5.1.2.12 RF — Radio Frequency
5.1.2.13 UV — Ultraviolet
5.2 Definitions
5.2.1 Acid — a corrosive material whose chemical reaction characteristic is that of an electron acceptor. [SEMI F21,
SEMI S4]
5.2.2 Anion — a negatively charged ion that is attracted to an anode in electrolysis.
5.2.3 Cation — a positively charged ion; an ion that is attracted to the cathode in electrolysis. These are typically ions
of metallic elements.
5.2.4 Chemically assisted elastomeric degradation – the breakdown process of a seal surface caused by polymer
degradation that involves a change of the polymer properties due to a chemical reaction with the polymer’s
surroundings.4
4
In Wikipedia, modified on 3 October 2013, at 14:18; from http://en.wikipedia.org/wiki/Chemically_assisted_degradation_of_polymers
This is a Draft Document of the SEMI International Standards program. No material on this page is to be construed as an official or adopted Standard or Safety Guideline.
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5.2.5 Mechanical deformation — the alteration of a seal caused by mechanical means, such as abrasion, rubbing, and
compression.
5.2.6 Chemical property — chemical durability is a measure of corrosion or attack of a glass surface when subjected
to a specific reagent, such as acid, base, or water at a specific concentration for a specific time and temperature. [SEMI
D9]
5.2.7 Chemical reaction — a process that involves change in the structure of ions or molecules.
5.2.8 Seal Chemical Compatibility — the ability of the molecules of a seal to coexist with process chemistries without
the degradation of either.
5.2.9 Corrosives — a chemical that causes visible destruction of, or irreversible alterations in, living tissue by
chemical action at the site of contact. A chemical is considered to be corrosive if, when tested on the intact skin of
albino rabbits by the method described in the U.S. Department of Transportation in Appendix A to 49 CFR 173, it
destroys or changes irreversibly the structure of the tissue at the site of contact following an exposure period of four
hours. This term shall not refer to action on inanimate surfaces. [SEMI S4]
5.2.10 Deionized water — (specified with resistivity ≥18 MΩ/cm, cations: Na, Fe, Ca ≤0.2 µg/l).
[SEMI E45]
5.2.11 Degradation — a chemical reaction leading to the reduction to a simpler molecular structure. See also chemical
breakdown.
5.2.12 Ion — an atom or group of atoms that has lost or gained one or more electrons.
5.2.13 Leak rate — rate at which an environment loses a vacuum (Millitorr liters/second).
5.2.14 Outgassing — a vacuum phenomenon wherein a substance spontaneously releases volatile constituents in the
form of vapors or gases. In rubber compounds, these constituents may include water vapor, plasticizers, air, inhibitors,
etc. 5
5.2.15 Oxidizer gas — a gas which will support combustion or increase the burning rate of a combustible material
with which it may come in contact. [SEMI S4]
5.2.16 Particle — a minute fragment or quantity of matter.6
5.2.17 Particle generation — molecules of material generated, in most cases, due to degradation of a material.
5.2.18 Permeation — process by which a gas or liquid to pass through a seal structure by diffusion.
5.2.19 Silica — silicon dioxide, occurring as quartz, etc.
5.2.20 Swell resistance — the ability of a material to resist increasing its volume when it has been immersed in a
liquid or exposed to vapor.
5.2.21 Weight loss — reduction in mass of a sealing compound through the result of a chemical or physical reaction.
6 Measuring Methodology / Sample Preparation
6.1 Total Organic Carbon (TOC) Testing
6.1.1 General:
6.1.1.1 Reference documents: SEMI F40 and SEMI F57.
6.1.2 Sample preparation and leaching conditions: Follow SEMI F40 and SEMI F57.
6.1.2.1 It is important to maintain sufficient surface area to liquid volume ratio to satisfy the detection limit and
specification requirements of SEMI F57 or other applicable specification.
6.1.2.2 TOC leaching test should be conducted using high purity materials for container in order to maintain detection
limits within criteria of SEMI F57.
5
6
Trelleborg Sealing Solutions, Sealing Technology & Engineering Glossary
Oxford English Dictionary (3rd ed.). Oxford University Press. September 2005.
This is a Draft Document of the SEMI International Standards program. No material on this page is to be construed as an official or adopted Standard or Safety Guideline.
Permission is granted to reproduce and/or distribute this document, in whole or in part, only within the scope of SEMI International Standards committee (document development)
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6.1.3 Testing: Analyze per ASTM D6317. If carbon content exceeds the limits of ASTM D6317 use ASTM D5904.
6.1.4 TOC reporting:
6.1.4.1 The reporting units are microgram per m2.
6.1.4.2 A complete sample description including manufacturer, material type, part number, lot number, processing
conditions, surface treatment, cutting or other sample manipulation for testing, and other sample history should be
included.
6.2 Surface Extractable Metallic Contamination
6.2.1 General: The extraction and analysis are per SEMI F57 for Surface Extractable Contamination. Alternate media
such as 2% nitric acid for one hour may be used, if specified by end-use condition.
6.2.2 Sample preparation:
6.2.2.1 Samples should be prepared per SEMI F40 and SEMI F57.
6.2.2.2 Record the weight and dimensions of all samples prior to testing.
6.2.3 Surface extraction:
6.2.3.1 No UHPW or other rinsing should be performed prior to the analysis.
6.2.3.1.1 Extraction:
6.2.3.1.1.1 UPW – Follow SEMI F57.
6.2.3.1.1.2 Acids (HF and Piranha; or specified) - 1 hour in concentrated acid as defined in requirements at ambient
temperature.
6.2.3.1.1.3 Conditions should be consistent for comparison and quality assessments.
6.2.4 Metals testing:
6.2.4.1 ICP-MS per SEMI F57.
6.2.4.2 Typical elements quantified are: Al, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Sb, Sn,
Sr, Ti, V, Zn, and Zr.
6.2.5 Reporting: Report units as µg/m2. Sample identification, dimensions and weight should be included in the
report.
6.3 Ash Metal Analysis
6.3.1 General:
6.3.1.1 Analysis of metals contents of the ash is reported per weight of the pre-ashed sample.
6.3.2 Sample Preparation:
6.3.2.1 Samples size should be limited to 2 grams.
6.3.2.2 No UPW rinse or pre-acid clean should be performed prior to the analysis unless it is needed to remove
potential surface contaminants that are not part of the bulk material.
6.3.3 Ashing condition: Ash in a muffle-type furnace until the material is fully ashed.
6.3.4 Metals testing:
6.3.4.1 ICP-MS.
6.3.4.1.1 Typical elements quantified are: Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Sb, Sn,
Sr, Ti, V, Zn, and Zr.
6.3.5 Reporting: Report as ng/gram or ppb of sample prior to ash.
This is a Draft Document of the SEMI International Standards program. No material on this page is to be construed as an official or adopted Standard or Safety Guideline.
Permission is granted to reproduce and/or distribute this document, in whole or in part, only within the scope of SEMI International Standards committee (document development)
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6.4 Outgassing Test
6.4.1 General:
6.4.1.1 The outgassing test should be performed per IEST-RP-CC031.3.
6.4.1.1.1 Sample and test variables that should be consistent when performing comparison assessment include:
sample size, sample exposed area, outgas time and temperature, gas flow rate, linear velocity of the gas over the
sample, and geometry/size and orientation of the sample and vessel.
6.4.2 Sample Preparation:
6.4.2.1 It is important to maintain consistent exposed surface areas to improve reproducibility and comparative results.
Very low outgassing materials may require the material to be cut to increase surface area during outgassing.
6.4.2.1.1 Cutting the material into very small pieces that are less than 1 mm in any dimension is preferred.
6.4.2.1.2 Samples should be delivered in a clean packaging to the lab.
6.4.2.1.3 Do not pre-clean the sample prior to placement in the sample vessel unless otherwise instructed by the
customer.
6.4.2.1.4 Appropriate handling techniques should be used that will not contaminate the sample during handling.
6.4.2.1.5 Record the weight and dimensions of all samples prior to testing. If the material is cut into very small pieces,
this should be noted in the report rather than recording dimensions.
6.4.2.1.6 Follow IEST-RP-CC031.3 instructions regarding analyzing blanks for each vessel used.
6.4.3 Testing: dynamic headspace/thermal desorption with cold trap and GC/MS system.
6.4.3.1 Outgas in baked quartz, SS or PFA sample vessel.
6.4.3.2 Separate outgas samples at two temperatures (100 °C, and 150 °C) for 30 minutes each. If the maximum
projected use temperature is greater than 150°C, it is recommended to have a third test at a temperature that is 25°C
greater than the maximum use temperature.
6.4.3.3 Utilize UHP He or N2 as the carrier gas at 100 mL/min flow rate.
6.4.3.4 Cryotrap temperature is 0-2°C.
6.4.3.5 Reference external standard such as hexadecane is to be used and documented in the reporting.
6.4.3.5.1 Follow IEST-RP-CC031.3 instructions regarding analyzing response of external standard.
6.4.4 Outgas Reporting
6.4.4.1 Results should be reported in ng/cm2 or ppmw for small cut up pieces or ng/part for parts with indeterminate
surface areas of the outgassing material.
6.4.4.2 A complete sample description including manufacturer, material type, processing conditions, surface
treatment, cutting or other sample manipulation for testing, and other sample features per IEST-RP-CC31.3 should be
included.
6.4.4.3 Instrument/system information should be reported per IEST-RP-CC31.3.
6.5 Ionics
6.5.1 Ionics should be determined per SEMI F57.
6.6 Permeability
6.6.1 General: Reference document: ISO 15105-1 and ASTM D1434.
6.6.1.1 Permeability is analyzed by volume of gas passing through a material with specified thickness, per unit area
and unit time, under unit partial pressure difference between the two sides of material. Test can be processed on singlelayer film or sheet of material or multi-layer structures under a differential pressure.
This is a Draft Document of the SEMI International Standards program. No material on this page is to be construed as an official or adopted Standard or Safety Guideline.
Permission is granted to reproduce and/or distribute this document, in whole or in part, only within the scope of SEMI International Standards committee (document development)
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7 Consideration for Perfluorooctanoic Acid (PFOA) and Fluorinated Telomers7
7.1 Perfluorooctanoic acid (PFOA) is a perfluorinated chemical (LCPFC) that does not occur naturally in the
environment. LCPFCs are synthetic chemical substances with special properties and hundreds of manufacturing and
industrial applications.
7.2 EPA has been investigating PFOA because:
7.2.1 It is very persistent in the environment
7.2.2 It is found at very low levels both in the environment and in the blood of the general U.S. population
7.2.3 It remains in people for a very long time
7.2.4 It causes developmental and other adverse effects in laboratory animals.
7.3 Major pathways that enable PFOA, in very small quantities, to get into human blood are not yet fully understood.
PFOA is used to make fluoropolymers and can also be released by the transformation of some fluorinated telomers.
However, consumer products made with fluoropolymers and fluorinated telomers, including Teflon® and other
trademark products, are not PFOA. Rather, some of them may contain trace amounts of PFOA and other related
perfluorinated chemicals as impurities. The information that EPA has available does not indicate that the routine use
of consumer products poses a concern. At present, there are no steps that EPA recommends that consumers take to
reduce exposures to PFOA.
7.4 EPA remains concerned about LCPFCs being produced by companies that are not participating in the stewardship
program and intends to take action to address those concerns. On December 30, 2009, EPA posted four action plans,
including an action plan on long-chain perfluorinated chemicals (LPFCs). The LCPFCs action plan outlines actions
that would further reduce exposure to LCPFCs by addressing their use in products from sources other than the eight
companies participating in the stewardship program. As these actions begin, there will be opportunities for public and
stakeholder comment and involvement.
8 Considerations for Use in Ultrapure Deionized Water
8.1 Deionized water is used in many wafer processing steps and should not contribute any contaminants to the
processes. The most common sealing requirements in DI water systems are for filters, valves, flow and pressure
regulators, and fittings.
8.2 Contaminants in DI water fall primarily into three categories. They are: ion contamination, TOCs and bacterial
growth. Contaminant levels are usually expressed in parts per billion (PPB).
8.3 Ion contamination problems are caused by anionic and cationic elements in DI water such as fluorides, chlorides,
sulfates, etc. These can be leached from seals as well as the DI plumbing.
8.4 In order to kill bacteria which have a propensity to grow in DI water, the water is either heated (>80°C+), ozonized,
or exposed to high levels of UV light (typically 254 nanometer wavelength), or possibly a combination of these three
elements. These treatments pose unique problems for seals used in the DI system such as: contamination of the DI
water by TOCs being leached from the seals; leaking of the DI plumbing due to temperature changes; seal failure due
to exposure to strong oxidizing agents; and seal failure due to UV exposure. Ozone and UV deterioration of the seals
usually leads to particulate contamination.
8.5 Considerations:
8.5.1 What method of sterilization (i.e., chemical, thermal or radiation)?
8.5.2 Concerns for cations, anions, or TOCs?
8.5.3 Seal life expectation?
9 Considerations for Use in Corrosives (Acids, Bases), Oxidizers, and Solvents
9.1 Inorganic wet chemicals at high concentration levels and in some cases at elevated temperatures are often used in
front-end semiconductor processing. Most common sealing requirements are in acid recirculation and bulk chemical
7
The EPA PFOA website http://www.epa.gov/oppt/pfoa/index.html
This is a Draft Document of the SEMI International Standards program. No material on this page is to be construed as an official or adopted Standard or Safety Guideline.
Permission is granted to reproduce and/or distribute this document, in whole or in part, only within the scope of SEMI International Standards committee (document development)
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distribution systems (BCDS). Component systems include pumps, filters, mega sonic seals, gaskets for pipeline
interfaces and valves.
9.2 Of primary concern when specifying a seal for an application are issues relating to resistance to chemical reaction.
Design considerations should include resistance to chemical breakdown, static vs. dynamic environments, pressure,
temperature, leachables, and particle generation.
9.3 Chemical and Thermal Degradation involves the incompatibility of the seals to the process chemistries. An
example is Hydrofluoric Acid (HF) dissolves silicone elastomers. The same is true of thermal degradation (i.e., Piranha
or Phosphoric Acids) where the process temperature causes thermally and chemically induced effects on the seal that
can also contributes to the mechanical failure of the seal.
9.4 Leaching is most commonly associated with metal filler systems of the seal, which usually introduce metallic
ions. This is a continuous occurrence as long as the seal is in the system.
9.4.1 Particles — Particles can be the result of mechanical damage of the seal or as a result of leaching, chemical
degradation or foreign material present on the seal surface. In summary, all cases of the above contamination can
create electrical shorts, voids, and unwanted doping on the wafer being processed.
9.4.2 Solvents — Incompatibility of elastomers or seals with solvent chemistries may cause contamination.
9.4.2.1 For example, there are degrees of incompatibility:
9.4.2.2 If the seal is dissolved by the solvent, then a catastrophic failure occurs where the solvent leaks out of the
liquid process loop.
9.4.2.3 Another type of solvent seal interaction is the swelling of the elastomer or the leaching of small amounts of
elastomer. Excessive swelling of the elastomer can result in premature seal failures and a higher cost of ownership
caused by increased frequency of seal change outs.
10 Considerations for Use In Thermal Processes
10.1 Thermal processes are used primarily for growth of oxide layers and to anneal crystal damage caused by implant.
Diffusion furnaces are usually batch process equipment where the process atmosphere is constrained within quartz
tubes. The seals of these tubes are exposed to temperatures of 250°C–300°C. This requires that the seals not only be
capable of withstanding these high temperatures but also not out-gas or permeate, thus adversely affecting the purity
of the process. Also of concern is the possible particle generation caused by the seals as they expand and contract due
to temperature cycling (see § 9.4.1).
10.1.1 Factors include:
10.1.1.1 Temperature capability of material and process temperature.
10.1.1.2 Static or dynamic state of seal.
10.1.1.3 Proper sizing and fit of seal to gland.
11 Considerations for Use in Plasma Systems (Etch, CVD, and PVD)
11.1 Considerations for sealing components for use in plasma applications should include proximity to plasma,
plasma reactor temperature; chemical composition of plasma; plasma energy; and chemical reaction caused by the
plasma.
11.2 Contamination from sealing components and particle generation is directly related to other considerations
mentioned above.
11.2.1 Factors include:
11.2.1.1 Seal composition and resistance to chemical attack.
11.2.1.2 Proximity to source and intensity of RF.
11.2.1.3 Temperature capability of material and process temperature.
11.2.1.4 Static or dynamic state of seal.
This is a Draft Document of the SEMI International Standards program. No material on this page is to be construed as an official or adopted Standard or Safety Guideline.
Permission is granted to reproduce and/or distribute this document, in whole or in part, only within the scope of SEMI International Standards committee (document development)
activity. All other reproduction and/or distribution without the prior written consent of SEMI is prohibited.
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Doc. 5080B  SEMI
LETTER BALLOT
Document Number: 5080B
Date: 3/14/2016
Semiconductor Equipment and Materials International
3081 Zanker Road
San Jose, CA 95134-2127
Phone: 408.943.6900, Fax: 408.943.7943
DRAFT
11.2.1.5 Proper sizing and fit of seal to gland
12 Related Documents
12.1 SEMI Standards
SEMI E49 — Guide for Standard Performance Practices, and Sub-Assembly for High Purity Piping Systems and Final
Assembly for Semiconductor Manufacturing Equipment
SEMI F40 — Practice for Preparing Liquid Chemical Distribution Components for Chemical Testing
12.2 Other Documents
12.2.1 “Recommendation for the Analytical Methods to be Used with SEMI F51,” Slava Libman, Air Liquide
Electronics U.S. LP.
12.2.2 “Procedure for analyzing extractable components from Semiconductor Seals,” Eric Adair, 3M.
12.2.3 Millipore 9th Annual Microelectronics Technical Symposium, May 20, 1991, “Contamination Derived from
O-Rings,” Robert Matthews.
12.2.4 RTP’97 5th International Conference on Advanced Thermal Processing of Semiconductors, “Sealing
Technology for the Semiconductor Industry,” Dalia Vernikovsky.
12.2.5 “Setting Standards for Sealing,” Semiconductor International 2011, Dalia Vernikovsky.
12.2.6 “Applied Seals North America (ASNA) Discusses the Seals Industry and Technology,” Gas & Instruments
Oct 2010; Dalia Vernikovsky.
12.2.7 “The Material Science of Seals: Part 1,” Gas & Instruments Jan/Feb 2011; Dalia Vernikovsky.
12.2.8 ISMI Manufacturing Week 2011, “The Science Behind the Seals, The Reality,” Dalia Vernikovsky.
12.2.9 “Efficiency in Sealing: A BKM case Study,” Dalia Vernikovsky, Brad Ecker and Seth Urbach.
12.2.10 “SEMI Semiconductor Components, Instruments, and Subsystems (SCIS) Working Group Addresses
Defectivity, Variability and Reliability”, Gas & Instruments May/Jun 2014, Dalia Vernikovsky, Barry Gotlinsky.
12.2.13 “Defeating Defectivity and Variability in Semiconductor Sub-Components (SCIS/Defectivity Committee),”
Gas & Instruments Nov/Dec 2014, Dalia Vernikovsky.
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.
This is a Draft Document of the SEMI International Standards program. No material on this page is to be construed as an official or adopted Standard or Safety Guideline.
Permission is granted to reproduce and/or distribute this document, in whole or in part, only within the scope of SEMI International Standards committee (document development)
activity. All other reproduction and/or distribution without the prior written consent of SEMI is prohibited.
Page 9
Doc. 5080B  SEMI
LETTER BALLOT
Document Number: 5080B
Date: 3/14/2016