Patent US1624649A successfully refreshed from Google Patents.
US4134778A
Expired / Lapsed
US
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Selective irradiation of thyristors
Assignee: General Electric Co
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Filing: 1977-09-02
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Granted: 1979-01-16
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Expires: 1997-09-02
Abstract
Abstract The dv/dt characteristics of a bidirectional thyristor are improved by irradiating selected portions of the device with high energy crystal lattice-damaging particles. In an exemplary embodiment, the commutating dv/dt of a triac is enhanced by the masked, selective irradiation of the boundaries between conducting portions and between the gate and the conducting portions.
Inventors
- 👤 William W. Sheng
- 👤 Y. S. Edmund Sun
- 👤 Edward G. Tefft
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:00
CPC Classifications
H; H10; H10D; H10D18/00; H10D18/80; H10P; H10P34/00; H10P34/40; Y; Y10; Y10S; Y10S148/00; Y10S148/024
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
96 words
A method for improving the characteristics of bi-directional semiconductor switches of the type including a first current conducting region for conducting in a first direction, a second current conducting region for conducting in a second direction opposite said first direction, said second current conducting region laterally spaced apart from said first current conducting region and forming a first boundary therebetween, and a gate region spaced apart from and having a common boundary with both said first and said second current conducting regions, said method comprising: selectively irradiating said first boundary to form lifetime reducing defects therealong.
Claim 2
Independent Claim
96 words
A method for improving the characteristics of bi-directional semiconductor switches of the type including a first current conducting region for conducting in a first direction, a second current conducting region for conducting in a second direction opposite said first direction, said second current conducting region laterally spaced apart from said first current conducting region and forming a first boundary therebetween, and a gate region spaced apart from and having a common boundary with both said first and said second current conducting regions, said method comprising: selectively irradiating said first boundary to form lifetime reducing defects therealong.
Claim 3
Dependent Claim
23 words
The method of claim 1 wherein said irradiating comprises irradiating said first boundary with electrons at an energy in excess of 400 KeV.
Claim 4
Dependent Claim
30 words
The method of claim 1 wherein said selectively irradiating comprises masking essentially all of the said switches except for said first boundary, and exposing said masked switches to defect-creating irradiation.
Claim 5
Dependent Claim
17 words
The method of claim 1 further comprising irradiating said common boundary to form lifetime reducing defects therealong.
Claim 6
Dependent Claim
21 words
The method of claim 2 wherein said irradiating comprises irradiating said boundary at an energy between 400 KeV and 12 MeV.
Claim 7
Dependent Claim
26 words
The method of claim 5 wherein said irradiating comprises irradiating said boundary to a dosage of between about 10 12 and 10 15 e/cm 2 .
Claim 8
Dependent Claim
23 words
The method of claim 3 wherein said irradiating comprises irradiating said switches where the electrons have an energy in excess of 400 KeV.
Claim 9
Dependent Claim
23 words
The method of claim 7 wherein said irradiating comprises irradiating said switches with electrons having energies between about 400 KeV and 12 MeV.
Claim 10
Dependent Claim
23 words
The method of claim 8 wherein said irradiating comprises irradiating to a dosage between about 10 12 and 10 15 e/cm 2 .
Claim 11
Dependent Claim
21 words
The method of claim 4 wherein said irradiating comprises irradiating with electrons having an energy in excess of about 400 KeV.
Claim 12
Dependent Claim
48 words
The method of claim 4 wherein said selectively irradiating comprises masking essentially all of said semiconductor switches except for said first boundary and said common boundary, and exposing said masked switches to a source of irradiation for forming defects along said first boundary and along said common boundary.
Claim 13
Dependent Claim
22 words
The method of claim 10 wherein said irradiating comprises irradiating with electrons having an energy between about 400 KeV and 12 MeV.
Claim 14
Dependent Claim
24 words
The method of claim 12 wherein said irradiating comprises irradiating to a dosage of between about 10 12 and 10 15 e/cm 2 .
Claim 15
Dependent Claim
20 words
The method of claim 11 wherein said irradiating comprises irradiating with electrons having an energy in excess of 400 KeV.
Claim 16
Dependent Claim
22 words
The method of claim 14 wherein said irradiating comprises irradiating with electrons having an energy between about 400 KeV and 12 MeV.
Claim 17
Dependent Claim
24 words
The method of claim 15 wherein said irradiating comprises irradiating to a dosage of between about 10 12 and 10 15 e/cm 2 .
Claim 18
Independent Claim
104 words
A method for improving the electrical characteristics of bi-directional thyristors of the type including first and second laterally spaced apart current carrying regions in a single semiconductor body separated by a first boundary region, each said first and second regions having first, second, third, and fourth alternating conductivity type layers therein, at least one of said layers comprising a base layer and first and second electrodes for providing ohmic contact to said regions, said method comprising: irradiating said boundary region with semiconductor crystal lattice-damaging high energy particles for forming additional charge carrier recombination sites at least in said base layer in said boundary region.
Claim 19
Independent Claim
104 words
A method for improving the electrical characteristics of bi-directional thyristors of the type including first and second laterally spaced apart current carrying regions in a single semiconductor body separated by a first boundary region, each said first and second regions having first, second, third, and fourth alternating conductivity type layers therein, at least one of said layers comprising a base layer and first and second electrodes for providing ohmic contact to said regions, said method comprising: irradiating said boundary region with semiconductor crystal lattice-damaging high energy particles for forming additional charge carrier recombination sites at least in said base layer in said boundary region.
Claim 20
Dependent Claim
10 words
The method of claim 17 wherein said particles comprise electrons.
Claim 21
Dependent Claim
17 words
The method of claim 18 wherein said electrons comprise electrons having energies in excess of 400 KeV.
Claim 22
Dependent Claim
56 words
The method of claim 19 wherein said thyristors further include a first gate region including a first gate electrode thereon separated from said first and second current carrying regions by a second boundary region and said method further comprises irradiating said second boundary region with crystal lattice damaging electrons having energies in excess of 400 KeV.
Claim 23
Dependent Claim
44 words
The method of claim 19 wherein said thyristors comprise triacs and said irradiating comprises: masking said first and second current carrying regions; and irradiating said triac with lattice damaging high energy particles so that essentially only said first boundary is impacted by said particles.
Claim 24
Dependent Claim
48 words
The method of claim 20 wherein said thyristors comprise triacs and said irradiating comprises: masking said first and second current carrying regions and said gate region; and irradiating said triac so that essentially only said first and said second boundary regions are impacted by said high energy electrons.
Claim 25
Dependent Claim
20 words
The method of claim 21 wherein said masking step comprises: coating said first and second electrodes with high lead solder.
Claim 26
Dependent Claim
40 words
The method of claim 21 wherein said masking comprises covering said first and second current carrying regions with a shield of sufficient thickness to effectively prevent particles having sufficient energy to cause lattice damage from reaching said current carrying regions.
Claim 27
Dependent Claim
25 words
The method of claim 22 wherein said masking step comprises coating said first and second electrodes and said first gate electrodes with high lead solder.
Claim 28
Dependent Claim
48 words
The method of claim 22 wherein said masking comprises covering said first and second current carrying regions and said gate region with a shield of sufficient thickness to effectively prevent particles having sufficient energy to cause lattice damage from reaching said current carrying regions or said gate regions.
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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) | 1982-01-15 | 1982-07-17 | 1983-01-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-01-15 | 1986-07-17 | 1987-01-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-01-15 | 1990-07-17 | 1991-01-16 | $7700.00 | Window Closed / Lapsed |