Patent US2749377A successfully refreshed from Google Patents.
Patent US5151766A successfully refreshed from Google Patents.
US5151766A
Expired / Lapsed
US
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Semiconductor component
Assignee: ABB Schweiz AG
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Filing: 1991-06-11
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Granted: 1992-09-29
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Expires: 2011-06-11
Abstract
Abstract In order to improve overall the trade-off between forward voltage drop and turn-off time, in a doped zone an axially limited region is provided with recombination centers. The recombination centers form a trap density profile varying periodically in one or two dimensions transverse to the axial direction. The period corresponds approximately to the bulk diffusion length of the minority charge carriers in the doped zone. Preferably, the change in the trap density profile from segments of low trap density to segments of high trap density takes place abruptly. The sections of low trap density and those of high trap density are approximately of the same size in terms of area.
Inventors
- 👤 Marcel Huppi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 13:09
CPC Classifications
H; H10; H10P; H10P34/00; H10P34/40; H10D; H10D62/00; H10D62/50; H10D62/53; H10P32/00; H10P32/10; H10P32/17; H10P32/171; H10P32/18
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
196 words
A semiconductor element having a current direction that can switch from a conducting into a non-conducting state, comprising (a) a doped zone having minority charge carriers, which in the non-conducting state have a given mean bulk lifetime Tau SRH and thus a mean bulk diffusion length LD, Bulk and in the conducting state, in which the doped zone is swamped by minority charge carriers in an axial direction parallel to the current direction, having a shortened lifetime Tau Aug by virtue of the Auger recombination, and (b) a region limited in said axial direction, located at a given depth in the doped zone, in which region there is a pulse shaped concentration profile of recombination centers for reducing the mean bulk lifetime Tau SRH of the minority charge carriers; said axially limited region having a length in the axial direction which is smaller or equal to the length of said doped zone; wherein (c) the recombination centers form a trap density profile varying periodically transverse to said axial direction, in which segments of low trap density alternate with segments of high trap density with a period corresponding approximately to the bulk diffusion length L D ,Bulk.
Claim 2
Dependent Claim
196 words
A semiconductor element having a current direction that can switch from a conducting into a non-conducting state, comprising (a) a doped zone having minority charge carriers, which in the non-conducting state have a given mean bulk lifetime Tau SRH and thus a mean bulk diffusion length LD, Bulk and in the conducting state, in which the doped zone is swamped by minority charge carriers in an axial direction parallel to the current direction, having a shortened lifetime Tau Aug by virtue of the Auger recombination, and (b) a region limited in said axial direction, located at a given depth in the doped zone, in which region there is a pulse shaped concentration profile of recombination centers for reducing the mean bulk lifetime Tau SRH of the minority charge carriers; said axially limited region having a length in the axial direction which is smaller or equal to the length of said doped zone; wherein (c) the recombination centers form a trap density profile varying periodically transverse to said axial direction, in which segments of low trap density alternate with segments of high trap density with a period corresponding approximately to the bulk diffusion length L D ,Bulk.
Claim 3
Dependent Claim
25 words
The semiconductor component as claimed in claim 1, wherein transverse to said axial direction the recombination centers form a two-dimensionally periodically varying trap density profile.
Claim 4
Dependent Claim
56 words
The semiconductor component as claimed in claim 1, wherein (a) in segments of low trap density and in segments of high trap density the trap density profile respectively approximately assumes a constantly low or constantly high value, and (b) the change from segments of low trap density to segments of high trap density takes place abruptly.
Claim 5
Dependent Claim
32 words
The semiconductor component as claimed in claim 3, wherein the segments of low trap density and the segments of high trap density are approximately of the same size in terms of area.
Claim 6
Dependent Claim
225 words
A semiconductor element having a current direction that can switch from a conducting into a non-conducting state, comprising (a) a doped zone having minority charge carriers, which in the non-conducting state have a given mean bulk lifetime Tau SRH and thus a mean bulk diffusion length LD, Bulk and in the conducting state, in which the doped zone is swamped by minority charge carriers in an axial direction parallel to the current direction, having a shortened lifetime Tau Aug by virtue of the Auger recombination, and (b) a region limited in said axial direction, located at a given depth in the doped zone, in which region there is a pulse shaped concentration profile of recombination centers for reducing the mean bulk lifetime Tau SRH of the minority charge carriers; said axially limited region having a length in the axial direction which is smaller or equal to the length of said doped zone; wherein (c) the recombination centers form a trap density profile varying periodically transverse to said axial direction, in which segments of low trap density alternate with segments of high trap density with a period corresponding approximately to the bulk diffusion length L D ,Bulk, and (d) in said axial direction the doped zone adjoins a highly doped zone that injects minority charge carriers, and forms with said zone a rapidly switching p-n junction.
Claim 7
Dependent Claim
225 words
A semiconductor element having a current direction that can switch from a conducting into a non-conducting state, comprising (a) a doped zone having minority charge carriers, which in the non-conducting state have a given mean bulk lifetime Tau SRH and thus a mean bulk diffusion length LD, Bulk and in the conducting state, in which the doped zone is swamped by minority charge carriers in an axial direction parallel to the current direction, having a shortened lifetime Tau Aug by virtue of the Auger recombination, and (b) a region limited in said axial direction, located at a given depth in the doped zone, in which region there is a pulse shaped concentration profile of recombination centers for reducing the mean bulk lifetime Tau SRH of the minority charge carriers; said axially limited region having a length in the axial direction which is smaller or equal to the length of said doped zone; wherein (c) the recombination centers form a trap density profile varying periodically transverse to said axial direction, in which segments of low trap density alternate with segments of high trap density with a period corresponding approximately to the bulk diffusion length L D ,Bulk, and (d) in said axial direction the doped zone adjoins a highly doped zone that injects minority charge carriers, and forms with said zone a rapidly switching p-n junction.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-09-29 | 1996-03-30 | 1996-09-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-09-29 | 2000-03-30 | 2000-09-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-09-29 | 2004-03-30 | 2004-09-29 | $7700.00 | Window Closed / Lapsed |