US4297149A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of treating SiPOS passivated high voltage semiconductor device
Assignee: Intersil Corp
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Filing: 1980-05-05
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Granted: 1981-10-27
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Expires: 2000-05-05
Abstract
Abstract The breakdown voltage of high voltage semiconductor devices passivated with SiPOS deteriorates if the devices are allowed to soak at temperatures in the 400° C. to 525° C. range. The original breakdown voltage is recovered by annealing the devices at a temperature of above about 550° C. prior to metallization and alloying the metal at less than 425° C.
Inventors
- 👤 Patrick R. Koons
- 👤 John M. S. Neilson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 19:29
CPC Classifications
H; H10; H10P; H10P95/00; H10P95/90; Y; Y10; Y10S; Y10S257/00; Y10S257/905; Y10S438/00; Y10S438/958
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
102 words
In a process of fabricating a semiconductor device having oxygenated polycrystalline silicon passivation layers the improvement comprising: annealing the devices at at least 525° C. prior to metallization; cooling the devices rapidly through the 500° C. to 450° C. temperature range at the end of said annealing; preventing the devices from subsequently being heated to any temperature higher than 425° C.; and preventing the devices from being exposed to any temperature above 400° C. for longer than a total of ten minutes subsequent to the annealing whereby the devices will have near the maximum breakdown voltage of which their structure is capable.
Claim 2
Dependent Claim
102 words
In a process of fabricating a semiconductor device having oxygenated polycrystalline silicon passivation layers the improvement comprising: annealing the devices at at least 525° C. prior to metallization; cooling the devices rapidly through the 500° C. to 450° C. temperature range at the end of said annealing; preventing the devices from subsequently being heated to any temperature higher than 425° C.; and preventing the devices from being exposed to any temperature above 400° C. for longer than a total of ten minutes subsequent to the annealing whereby the devices will have near the maximum breakdown voltage of which their structure is capable.
Claim 3
Dependent Claim
20 words
The method recited in claim 1 wherein: said annealing step is performed at a temperature of at least 550° C.
Claim 4
Dependent Claim
21 words
The method recited in claim 1 wherein: said annealing step is carried out for a period of at least one-half hour.
Claim 5
Dependent Claim
30 words
The method recited in claim 1 wherein subsequent to metal deposition: the metal is alloyed with the semiconductor at a temperature in the range between 400° C. and 425° C.
Claim 6
Dependent Claim
20 words
The method recited in claim 1 wherein: said rapid cooling is through the 525° C. to 400° C. temperature range.
Claim 7
Independent Claim
61 words
A method of maximizing the breakdown voltage of semiconductor devices having oxygenated polycrystalline silicon passivation layers comprising: annealing said devices at a temperature above 525° C. prior to metallizing the devices; cooling said devices rapidly through the temperature range 525° C. to 425° C. following said annealing; preventing said devices from being heated to above 425° C. subsequent to said annealing.
Claim 8
Independent Claim
61 words
A method of maximizing the breakdown voltage of semiconductor devices having oxygenated polycrystalline silicon passivation layers comprising: annealing said devices at a temperature above 525° C. prior to metallizing the devices; cooling said devices rapidly through the temperature range 525° C. to 425° C. following said annealing; preventing said devices from being heated to above 425° C. subsequent to said annealing.
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) | 1984-10-26 | 1985-04-27 | 1985-10-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-10-26 | 1989-04-27 | 1989-10-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-10-26 | 1993-04-27 | 1993-10-27 | $7700.00 | Window Closed / Lapsed |