Patent US4476481A successfully refreshed from Google Patents.
US4476481A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low-loss P-i-n diode
Assignee: Toshiba Corp
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Filing: 1982-06-03
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Granted: 1984-10-09
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Expires: 2002-06-03
Abstract
Abstract A low-loss P-i-n diode includes an i-type layer consisting of first and second i-type regions formed on the cathode layer of the diode and the i-type has a thickness W i of less than 25 μm. The impurity concentration of the first i-type region is higher than that of the second i-type region. To obtain a good forward-voltage V f , W i 2 /τ is selected to be in the range of 20-200cm cm 2/sec and the carrier lifetime τ of the i-type layer is controlled by a carrier lifetime killer with a small resistivity compensation effect which is diffused into the i-type layer. The P-i-n diode has a high reverse breakdown voltage, small forward-voltage drop and a short recovery time.
Inventors
- 👤 Susumu Iesaka
- 👤 Shigenori Yakushiji
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 23:07
CPC Classifications
H; H10; H10D; H10D8/00; H10D8/50; H10D62/00; H10D62/80; H10D62/83; H10D62/834
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
144 words
A P-i-n diode comprising: a semiconductor substrate of a first conductivity type which functions as the anode of the P-i-n diode; a first i-type layer of said first conductivity type formed on said semiconductor substrate and having a first thickness W 1 ; a second i-type layer of said first conductivity type formed on the first i-type layer and having a second thickness of W 2 ; said second i-type layer having an impurity concentration lower than that of said first i-type layer; carrier lifetime killer characterized by a small carrier compensation effect being diffused into said first and second i-type layers whereby said first and second i-type layers have a carrier lifetime of τ; and a region of second conductivity type diffused into said second i-type layer and having a thickness of W 3 which functions as the cathode of the P-i-n diode.
Claim 2
Dependent Claim
144 words
A P-i-n diode comprising: a semiconductor substrate of a first conductivity type which functions as the anode of the P-i-n diode; a first i-type layer of said first conductivity type formed on said semiconductor substrate and having a first thickness W 1 ; a second i-type layer of said first conductivity type formed on the first i-type layer and having a second thickness of W 2 ; said second i-type layer having an impurity concentration lower than that of said first i-type layer; carrier lifetime killer characterized by a small carrier compensation effect being diffused into said first and second i-type layers whereby said first and second i-type layers have a carrier lifetime of τ; and a region of second conductivity type diffused into said second i-type layer and having a thickness of W 3 which functions as the cathode of the P-i-n diode.
Claim 3
Dependent Claim
31 words
The P-i-n diode of claim 1 wherein W 1 2 /τ is in the range of 20-200 cm 2 /sec where W i equals W 1 +W 2 -W 3 .
Claim 4
Dependent Claim
15 words
The P-i-n diode as claimed in claim 1 wherein the carrier lifetime killer is platinum.
Claim 5
Dependent Claim
23 words
The P-i-n diode as claimed in claim 1 wherein the thickness W 1 of the first i-type layer is less than 5 μm.
Claim 6
Dependent Claim
22 words
The P-i-n diode as claimed in claim 1 wherein the thickness W 2 of the second i-type layer is approximately 25 μm.
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) | 1987-10-09 | 1988-04-09 | 1988-10-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-10-09 | 1992-04-09 | 1992-10-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-10-09 | 1996-04-09 | 1996-10-09 | $7700.00 | Window Closed / Lapsed |