US4693173A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Clean room
Assignee: Hitachi Ltd
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Filing: 1985-10-11
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Granted: 1987-09-15
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Expires: 2005-10-11
Abstract
Abstract A clean room wherein clean air obtained through filters from the upper portion of the clean room is blown toward the floor, through the openings in the floor, and with the clean air being discharged again through the filters from the upper portion of the clean room. The air flow rate of clean air in the aisle areas is greater than the air flow rate in the wafer handling areas, and the opening rate of the floor is smaller in the portion near to an air return under the floor than in the portion remote from the air return thereby greatly reducing the diffusion of dust to the wafer handling areas.
Inventors
- 👤 Atsushi Saiki
- 👤 Michio Suzuki
- 👤 Hideo Sunami
- 👤 Shojiro Asai
- 👤 Michiyoshi Maki
- 👤 Kinichiro Asami
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 22:36
CPC Classifications
F; F24; F24F; F24F3/00; F24F3/12; F24F3/16; F24F3/167; B; B08; B08B; B08B15/00; F24F7/00; F24F7/04; F24F7/06; F24F7/10
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
137 words
A clean room comprising an upper portion, a floor means provided with a plurality of openings, filter means provided in said upper portion, means for blowing clean air through said filter means to the floor means and discharging the clean air through the openings, and air return means for returning air discharged through the openings to the blowing means so as to enable blowing the clean air through said filter means to the floor means, the clean room including aisle areas where dust is generated and wafer handling areas into which dust diffuses, and wherein said means for blocking is adapted to provide an air flow rate of said clean air in the aisle which is larger than an air flow rate in the wafer handling areas whereby dust diffusion into the wafer handling areas is reduced.
Claim 2
Dependent Claim
137 words
A clean room comprising an upper portion, a floor means provided with a plurality of openings, filter means provided in said upper portion, means for blowing clean air through said filter means to the floor means and discharging the clean air through the openings, and air return means for returning air discharged through the openings to the blowing means so as to enable blowing the clean air through said filter means to the floor means, the clean room including aisle areas where dust is generated and wafer handling areas into which dust diffuses, and wherein said means for blocking is adapted to provide an air flow rate of said clean air in the aisle which is larger than an air flow rate in the wafer handling areas whereby dust diffusion into the wafer handling areas is reduced.
Claim 3
Dependent Claim
38 words
A clean room as claimed in claim 1, wherein an opening rate of said floor means is less in a portion thereof near to the air return means than in a portion remote from said air return means.
Claim 4
Dependent Claim
26 words
A clean room as claimed in claim 2, wherein the opening rate in a portion near to said air return means is not greater than 20%.
Claim 5
Dependent Claim
43 words
A clean room as claimed in claim 2, wherein said opening rate of the floor means is 5-20% in the portion near to said air return means, 25-45% in an adjacent portion, and 50-70% in a portion farthest from said air return means.
Claim 6
Dependent Claim
18 words
A clean room according to claim 2, wherein said air return means is disposed below said floor means.
Claim 7
Dependent Claim
32 words
A clean room according to claim 1, wherein the air flow rate in the wafer handling areas is 0.25-0.50 m/s and the air flow rate in the aisle areas os 0.50-1.00 m/s.
Claim 8
Dependent Claim
34 words
A clean room according to claim 1, wherein the air flow rate in the wafer handling areas is around 0.35 m/s and the air flow rate in the aisle areas is around 0.70 m/s.
Claim 9
Dependent Claim
120 words
In a clean room comprising means for blowing out clean air obtained through filters from the upper portion of said clean room to the floor, discharging it through openings in the floor, and blowing it again through said filters from an upper portion of said clean room to the floor, a clean room wherein an air flow rate of said clean air in aisle areas where dust is generated is larger than an air flow rate in wafer handling areas into which dust diffuses, whereby dust diffusion into the wafer handling areas is reduced, and wherein the air flow rate in the wafer handling areas is 0.25-0.50 m/s and the air flow rate in the aisle areas is 0.50-1.00 m/s.
Claim 10
Dependent Claim
120 words
In a clean room comprising means for blowing out clean air obtained through filters from the upper portion of said clean room to the floor, discharging it through openings in the floor, and blowing it again through said filters from an upper portion of said clean room to the floor, a clean room wherein an air flow rate of said clean air in aisle areas where dust is generated is larger than an air flow rate in wafer handling areas into which dust diffuses, whereby dust diffusion into the wafer handling areas is reduced, and wherein the air flow rate in the wafer handling areas is 0.25-0.50 m/s and the air flow rate in the aisle areas is 0.50-1.00 m/s.
Claim 11
Dependent Claim
121 words
A clean room comprising means for blowing out clean air obtained through filters from an upper portion of said clean room to the floor, discharging it through openings in the floor, and blowing it again through said filters from the upper portion of said clean room to the floor, a clean room wherein an air flow rate of said clean air in aisle areas where dust is generated is larger than an air flow rate in wafer handling areas into which dust diffuses, and wherein ther air flow rate in the wafer handling areas is around 0.35 m/s and the air flow rate in the aisle areas is around 0.70 m/s, whereby dust diffusion into the wafer handling areas is reduced.
Claim 12
Dependent Claim
121 words
A clean room comprising means for blowing out clean air obtained through filters from an upper portion of said clean room to the floor, discharging it through openings in the floor, and blowing it again through said filters from the upper portion of said clean room to the floor, a clean room wherein an air flow rate of said clean air in aisle areas where dust is generated is larger than an air flow rate in wafer handling areas into which dust diffuses, and wherein ther air flow rate in the wafer handling areas is around 0.35 m/s and the air flow rate in the aisle areas is around 0.70 m/s, whereby dust diffusion into the wafer handling areas is reduced.
Claim 13
Dependent Claim
114 words
A clean room comprising an upper portion a floor means provided with a plurality of openings, filter means provided in said upper portion, means for blowing clean air through said filter means to the floor means and discharging the clean air through the plurality of openings in the floor means, and a return means for returning the air discharged through the openings to the blowing means so as to enable a blowing of the clean air through said filter means to the floor means, and wherein an opening rate of said floor means is less in a portion near to the air return means than in a portion remote from said air return means.
Claim 14
Dependent Claim
114 words
A clean room comprising an upper portion a floor means provided with a plurality of openings, filter means provided in said upper portion, means for blowing clean air through said filter means to the floor means and discharging the clean air through the plurality of openings in the floor means, and a return means for returning the air discharged through the openings to the blowing means so as to enable a blowing of the clean air through said filter means to the floor means, and wherein an opening rate of said floor means is less in a portion near to the air return means than in a portion remote from said air return means.
Claim 15
Dependent Claim
29 words
The clean room as claimed in claim 10 wherein the opening rate of the floor in the portion near to said air return means is not greater than 20%.
Claim 16
Dependent Claim
41 words
The clean room as claimed in claim 10 wherein said opening rate of the floor is 5-20% in the portion nearest to said air return means, 25-45% in an adjacent portion, and 50-70% in portion farthest from said air return means.
Claim 17
Dependent Claim
18 words
A clean room according to claim 10, wherein said air return means is disposed below said floor means.
Claim 18
Dependent Claim
30 words
A clean room as claimed in claim 10, wherein the opening rate of the floor means in the portion near to said air return means is not greater than 20%.
Claim 19
Dependent Claim
43 words
A clean room as claimed in claim 10, wherein the opening rate of the floor means is 5-20% in the portion nearest to said air return means, 25-45% in an adjacent portion, and 50-70% in a portion farthest from said air return means.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-09-14 | 1991-03-16 | 1991-09-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-09-14 | 1995-03-16 | 1995-09-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-09-14 | 1999-03-16 | 1999-09-15 | $7700.00 | Window Closed / Lapsed |