US5542441A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for delivering ultra-low particle counts in semiconductor manufacturing
Assignee: YieldUP International
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Filing: 1994-08-03
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Granted: 1996-08-06
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Expires: 2014-08-03
Abstract
Abstract The invention relates to a wafer rinsing system for rinsing chemicals and particles off of wafers without introducing contaminants. The system reduces the particle count on wafers by filtering the water and the gas used during rinsing at the wet bench. The system includes a rinsing unit, a local water filter bank, a local gas filtering system, an H 2 O 2 injection unit, an auxiliary chemical injection unit, and a controller for operating the other components. The water filter bank provides a multiple stage filtering system to eliminate particles without a substantial drop in water pressure. The H 2 O 2 injection unit provides a local source of H 2 O 2 to clean the filter and rinser and to provide a mechanism for controlling the formation of native oxide on the wafer during rinsing. The auxiliary chemical injection unit provides a chemical additive to the rinsing unit to enhance the wafer cleaning process. The gas filtering system provides clean gas to the rinsing unit and to the injection units. The clean gas provides a clean atmosphere over the chemicals in each injection unit, and over the water in the rinser.
Inventors
- 👤 Raj Mohindra
- 👤 Abhay K. Bhushan
- 👤 Rajiv Bhushan
- 👤 Suraj Puri
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 22:15
CPC Classifications
H; H10; H10P; H10P70/00; H10P70/10; H10P70/15; H10P72/00; H10P72/04; H10P72/0402; H10P72/0406; Y; Y10; Y10S; Y10S134/00; Y10S134/902; Y10S210/00; Y10S210/90
Claims Analysis
Total Claims: 33
Claim 1
Independent Claim
88 words
An ultra-pure wafer rinsing system, comprising: a filter bank having a fluid input and a fluid output, said filter bank comprising a negatively charged filter operably coupled in series with a positively charged filter, said negatively charged filter and said positively charged filter being contained in a housing; and a rinser comprising an inner housing and an outer housing, said inner housing being connected to said fluid output and said outer housing being connected to a drain, said fluid output being located within 2 feet of said rinser.
Claim 2
Dependent Claim
88 words
An ultra-pure wafer rinsing system, comprising: a filter bank having a fluid input and a fluid output, said filter bank comprising a negatively charged filter operably coupled in series with a positively charged filter, said negatively charged filter and said positively charged filter being contained in a housing; and a rinser comprising an inner housing and an outer housing, said inner housing being connected to said fluid output and said outer housing being connected to a drain, said fluid output being located within 2 feet of said rinser.
Claim 3
Dependent Claim
18 words
The wafer rinsing system of claim 1, wherein said fluid output is within 1 foot of said rinser.
Claim 4
Dependent Claim
16 words
The system of claim 1 wherein said fluid input is coupled to a deionized water source.
Claim 5
Dependent Claim
22 words
The system of claim 3 wherein said rinser is adapted to cascade rinse fluid from said inner housing into said outer housing.
Claim 6
Dependent Claim
17 words
The system of claim 4 wherein said positively charged filter is a 0.1 micron and less filter.
Claim 7
Dependent Claim
17 words
The system of claim 5 wherein said negatively charged filter is a 0.1 micron and less filter.
Claim 8
Dependent Claim
14 words
The system of claim 6 wherein said filter bank has a minimal pressure drop.
Claim 9
Dependent Claim
23 words
The system of claim 7 wherein said housing includes a conductive shield to enclose said positively charged filter and said negatively charged filter.
Claim 10
Dependent Claim
21 words
The system of claim 8 wherein said housing comprises a grounding terminal, said grounding terminal being coupled to said conductive shield.
Claim 11
Dependent Claim
24 words
The system of claim 9 wherein said conductive shield is made from a material selected from a group consisting of aluminum and stainless steel.
Claim 12
Dependent Claim
22 words
The system of claim 10 wherein said fluid output comprises fluid substantially free from particles less than about 0.1 microns and greater.
Claim 13
Dependent Claim
17 words
The system of claim 11 wherein said inner housing is operable with a clean nitrogen gas purge.
Claim 14
Dependent Claim
143 words
A semiconductor wafer high purity rinsing system, comprising: a filter bank having a housing with an input and an output, said filter bank comprising a positively charged filter operably coupled to a negatively charged filter within said housing, said positively charged filter and said negatively charged filter being in series with each other and being coupled to said input and said output, said positively charged filter and said negatively charged filter being 0.1 micron and less filters; a rinser comprising an inner housing and an outer housing, said inner housing being operably coupled to said output and said outer housing being operably coupled to a drain, said rinser comprising a drain valve in said inner housing to drop a fluid level in said inner housing; and a controller operably coupled to said drain valve to drop said fluid level at a selected signal.
Claim 15
Dependent Claim
143 words
A semiconductor wafer high purity rinsing system, comprising: a filter bank having a housing with an input and an output, said filter bank comprising a positively charged filter operably coupled to a negatively charged filter within said housing, said positively charged filter and said negatively charged filter being in series with each other and being coupled to said input and said output, said positively charged filter and said negatively charged filter being 0.1 micron and less filters; a rinser comprising an inner housing and an outer housing, said inner housing being operably coupled to said output and said outer housing being operably coupled to a drain, said rinser comprising a drain valve in said inner housing to drop a fluid level in said inner housing; and a controller operably coupled to said drain valve to drop said fluid level at a selected signal.
Claim 16
Dependent Claim
27 words
The system of claim 13 further comprising a deionized water fluid source coupled to said input, said deionized water source comprising particles greater than about 0.1 microns.
Claim 17
Dependent Claim
28 words
The system of claim 14 further comprising a hydrogen peroxide injector operably coupled to said rinser, said hydrogen peroxide injector being adapted to remove bacteria from said rinser.
Claim 18
Dependent Claim
29 words
The system of claim 15 further comprising a control valve operably coupled between said rinser and said hydrogen peroxide injector, said control valve being operably coupled to said controller.
Claim 19
Dependent Claim
30 words
The system of claim 14 further comprising a hydrogen peroxide injector operably coupled to said filter bank, said hydrogen peroxide injector being adapted to remove bacteria from said filter bank.
Claim 20
Dependent Claim
15 words
The system of claim 14 further comprising a gas purger operably coupled to said rinser.
Claim 21
Dependent Claim
15 words
The system of claim 18 wherein said gas purger is a clean nitrogen gas purger.
Claim 22
Dependent Claim
15 words
The system of claim 14 further comprising an auxiliary injector operably coupled to said rinser.
Claim 23
Dependent Claim
28 words
The system of claim 20 further comprising a control valve operably coupled between said auxiliary injector and said rinser, said control valve being operably coupled to said controller.
Claim 24
Dependent Claim
243 words
Apparatus for high purity rinsing of semiconductor wafers, said apparatus comprising: a filter bank having a housing with an input and an output, said input being coupled to a fluid source comprising deionized water, said deionized water comprising particles greater than about 0.1 microns, said housing including a positively charged filter operably coupled to a negatively charged filter therein, said positively charged filter and said negatively charge filter in series with each other and being coupled to said input and said output, said positively charged filter and said negatively charged filter being 0.1 micron and less filters, said deionized water being substantially free from said particles greater than about 0.1 microns at said output; a rinser comprising an inner housing and an outer housing, said inner housing being operably coupled to said output and said outer housing being operably coupled to a drain, said rinser comprising a drain valve in said inner housing to drop a fluid level in said inner housing; a gas purger operably coupled to said rinser, said gas purger comprising a control valve to allow gas to purge said rinser to keep the ambient from entering said inner housing, said gas purger providing a gas substantially free from particles greater than about 0.1 microns; and a controller operably coupled to said drain valve to drop said fluid level in said inner housing, said controller being operably coupled to said control valve to purge said gas into said inner housing.
Claim 25
Dependent Claim
243 words
Apparatus for high purity rinsing of semiconductor wafers, said apparatus comprising: a filter bank having a housing with an input and an output, said input being coupled to a fluid source comprising deionized water, said deionized water comprising particles greater than about 0.1 microns, said housing including a positively charged filter operably coupled to a negatively charged filter therein, said positively charged filter and said negatively charge filter in series with each other and being coupled to said input and said output, said positively charged filter and said negatively charged filter being 0.1 micron and less filters, said deionized water being substantially free from said particles greater than about 0.1 microns at said output; a rinser comprising an inner housing and an outer housing, said inner housing being operably coupled to said output and said outer housing being operably coupled to a drain, said rinser comprising a drain valve in said inner housing to drop a fluid level in said inner housing; a gas purger operably coupled to said rinser, said gas purger comprising a control valve to allow gas to purge said rinser to keep the ambient from entering said inner housing, said gas purger providing a gas substantially free from particles greater than about 0.1 microns; and a controller operably coupled to said drain valve to drop said fluid level in said inner housing, said controller being operably coupled to said control valve to purge said gas into said inner housing.
Claim 26
Dependent Claim
22 words
The system of claim 22 wherein said rinser is adapted to cascade said fluid from said inner housing into said outer housing.
Claim 27
Dependent Claim
14 words
The system of claim 22 wherein said filter bank has a minimal pressure drop.
Claim 28
Dependent Claim
23 words
The system of claim 22 wherein said housing includes a conductive shield to enclose said positively charged filter and said negatively charged filter.
Claim 29
Dependent Claim
17 words
The system of claim 25 wherein said housing comprises a grounding terminal attached to said conductive shield.
Claim 30
Dependent Claim
24 words
The system of claim 26 wherein said conductive shield is made from a material selected from a group consisting of aluminum and stainless steel.
Claim 31
Dependent Claim
28 words
The system of claim 27 further comprising a hydrogen peroxide injector operably coupled to said rinser, said hydrogen peroxide injector being adapted to remove bacteria from said rinser.
Claim 32
Dependent Claim
30 words
The system of claim 27 further comprising a hydrogen peroxide injector operably coupled to said filter bank, said hydrogen peroxide injector being adapted to remove bacteria from said filter bank.
Claim 33
Dependent Claim
36 words
The system of claim 27 further comprising an auxiliary injector operably coupled to said rinser, said auxiliary injector providing a chemical selected from a group consisting of a solvent, a surfactant, an acid, and a caustic.
References Cited (Backward Citations)
US3252885A
Cited
US3973987A
Cited
US4655909A
Cited
US4917123A
Cited
US4990260A
Cited
US5160429A
Cited
US5377708A
Cited
US5073268A
Cited
US5128043A
Cited
US5331987A
Cited
US5190065A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-08-06 | 2000-02-05 | 2000-08-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-08-06 | 2004-02-05 | 2004-08-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-08-06 | 2008-02-05 | 2008-08-06 | $7700.00 | Window Closed / Lapsed |