Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – Processes of preparing a desired or intentional composition...
Patent
1998-09-29
2000-06-20
Michl, Paul R.
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
Processes of preparing a desired or intentional composition...
524243, 524375, 524488, C08K 520
Patent
active
060778946
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to instruments and wearable articles, used in a clean room in the field of manufacturing semiconductor devices, and more specifically to a wafer carrier (cassette), a standard mechanical interface POD (to be abbreviated as SMIF POD hereinafter), a wafer box, a wafer basket, and wafer handling jigs, which are used for handling semiconductor wafers in a clean room, and clean room shoes which are worn by an operator in a clean room.
BACKGROUND ART
Recently, as the degree of integration of semiconductor device increases, the width of a line of its circuit pattern is presently in a deep sub-micron. In the case where a circuit pattern of a line width of a deep sub-micron, the internal atmosphere of the clean room must be controlled to a cleanness of a high level. Under these circumstances, the problem of organic materials adsorbed to the surface of a wafer is recently focused, in addition to the conventional problem that particle-like dust adheres to the surface of a wafer (for example, "Gaseous Contaminants and Present Situation of Counter-measures Taken to Eliminate It" by Fujii, Air Cleaning Vol. 32, No. 3, P43 (1994), Japan Society of Air Cleaning).
The inventors of the present invention conducted intensive studies on any factors which could give rise to a source of organic material in a clean room. The result indicated that aliphatic hydrocarbons, organic carboxylic acid esters, phenols, oxides of these materials and amines are generated in very small amount, from resin-made instruments such as wafer carriers and SMIF POD.
Further, according to other studies carried out by the same inventors, it was found that organic carboxylic acid esters, phenols and oxides of these materials are generated in very small amount from the sole (made of resin) of a conventional clean room shoe, as a so-called out-gas.
These organic materials are adsorbed to the surfaces of wafers eventually via air streams in the clean room, causing a variety of bad effects in the formation of a circuit pattern. For example, in the case where a gate oxide film is formed on the surface of a wafer while some organic materials are adsorbed on the surface of the wafer, the start of the growth of the film is delayed, the sheet resistance value of the film is decreased, and the surface of the film becomes rough in projections and recesses.
DISCLOSURE OF INVENTION
The object of the present invention is to provide instruments and wearable articles, which can suppress the generation of organic materials as much as possible, when they are used in a clean room.
The inventors of the present invention examined organic materials in the atmosphere in the step of manufacturing a semiconductor device, and obtained the results shown in FIG. 1A. Further, they examined organic materials adhered to a semiconductor wafer during the step of manufacturing a semiconductor device, and obtained the results shown in FIG. 1B. When these results were taken as a whole, it was found that the detected organic materials were contained in the ordinary additives (lubricant, plasticizer, antioxidizing agent, antistatic agent) added to resin materials which constitute the instruments for handling substrates, such as wafer cassettes and SMIF POD.
The organic materials generated from these instruments are components contained in the lubricant, plasticizer, anti-oxidizing agent, antistatic agent, etc. which are added to the resin base. They are made of relatively light molecules, and consequently they easily evaporate from the resin base during the use, as an out gas. Specifically, the aliphatic hydrocarbons are generated from the lubricant added to enhance the moldability, the organic carboxylic acid esters are generated from the plasticizer added to maintain the material properties, the phenols and oxides thereof are generated from the anti-oxidizing agent added to prevent the deterioration due to oxidization, which would occur during or after the molding process, and the amines are generated from the antistatic agent added to
REFERENCES:
patent: 3761965 (1973-10-01), Barasch
patent: 3862877 (1975-01-01), Camden
patent: 3872515 (1975-03-01), Miner
patent: 4105567 (1978-08-01), Koerner
patent: 4251581 (1981-02-01), Schoppa
patent: 4272568 (1981-06-01), Berend
patent: 4333982 (1982-06-01), Rand
patent: 4752477 (1988-06-01), Kraft
patent: 4937277 (1990-06-01), O'Lenick
patent: 5273706 (1993-12-01), Laughner
patent: 5407715 (1995-04-01), Buddenhagen
patent: 5414051 (1995-05-01), Mason
patent: 5500477 (1996-03-01), Reuschel
patent: 5539062 (1996-07-01), Brown
patent: 5569485 (1996-10-01), Dahlquist
patent: 5660841 (1997-08-01), Kraft
patent: 5725867 (1998-03-01), Mixon
patent: 5742943 (1998-04-01), Chen
patent: 5846607 (1998-12-01), Hurley
patent: 5881386 (1999-03-01), Horwege
Imafuku Masayuki
Kobayashi Sadao
Matsuo Takenobu
Saito Misako
Wakabayashi Tsuyoshi
Michl Paul R.
Taisei Corporation
Tokyo Electron Limited
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