Patent US4021837A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4021837A Expired / Lapsed US ⏱️ 0.0 years remaining

Symmetrical semiconductor switch having carrier lifetime degrading structure

Assignee: Individual
•
Filing: 1975-04-21
•
Granted: 1977-05-03
•
Expires: 1995-04-21
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract The specification discloses a symmetrical semiconductor switch having a semiconductor body formed from a plurality of layers of alternating conductivity types to form a plurality of P-N junctions. Regions of one conductivity type are formed in the outer layers of the opposite conductivity type. Three electrodes contact the outer layers and the regions of the body to form a symmetrical semiconductor switch. Structure is provided on the outer layers of the body in order to degrade the lifetime of carriers which tend to move laterally across the switch in order to improve the switching time of the switch. In one embodiment, the structure comprises grooves formed in the outer layers of the body, the grooves being of sufficient width in order to substantially degrade the lifetime of carriers attempting to pass through layers adjacent the grooves. In another embodiment of the invention, carrier lifetime degrading material such as gold-doped glass is introduced into the body.

Inventors

  • 👤 Jearld L. Hutson

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 17:16
CPC Classifications
H; H10; H10D; H10D18/00; H10D18/80; H10D62/00; H10D62/10; H10D62/102

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 239 words
A semiconductor switch having symmetrical switching characteristics comprising: a semiconductor body having at least three layers of alternating first and second types of semiconductor material to form a plurality of interior P-N junctions, the first and second outer layers of said body being of said first type, first and second grooves formed in said first and second outer layers to electrically separate each of said outer layers into two areas, at least one of said interior layers being common to each of said two areas, said grooves including glass doped with material selected from a group comprising gold and platinum and operable to substantially eliminate the passage of carriers laterally across said body through said common interior layer from one of said areas to the other, a first region of said second type of semiconductor material formed in one of said areas of said first outer layer, a second region of said second type of semiconductor material formed in the other of said areas of said first outer layer, said first groove being disposed between said first and second regions, a first electrode contacting one of said areas and said first region, a second electrode contacting the other of said areas and said second region, a third region of said second type of semiconductor material formed in said second outer layer in one of said areas, and a third electrode contacting said second outer layer and said third region.
Claim 2
Dependent Claim 239 words
A semiconductor switch having symmetrical switching characteristics comprising: a semiconductor body having at least three layers of alternating first and second types of semiconductor material to form a plurality of interior P-N junctions, the first and second outer layers of said body being of said first type, first and second grooves formed in said first and second outer layers to electrically separate each of said outer layers into two areas, at least one of said interior layers being common to each of said two areas, said grooves including glass doped with material selected from a group comprising gold and platinum and operable to substantially eliminate the passage of carriers laterally across said body through said common interior layer from one of said areas to the other, a first region of said second type of semiconductor material formed in one of said areas of said first outer layer, a second region of said second type of semiconductor material formed in the other of said areas of said first outer layer, said first groove being disposed between said first and second regions, a first electrode contacting one of said areas and said first region, a second electrode contacting the other of said areas and said second region, a third region of said second type of semiconductor material formed in said second outer layer in one of said areas, and a third electrode contacting said second outer layer and said third region.
Claim 3
Dependent Claim 16 words
The semiconductor switch of claim 1 and comprising five layers of alternating types of semiconductor material.
Claim 4
Dependent Claim 30 words
The semiconductor switch of claim 1 wherein said grooves have sufficient width to degrade the lifetime of carriers attempting to pass laterally between said grooves through said common interior layer.
Claim 5
Dependent Claim 22 words
A semiconductor switch of claim 3 wherein said grooves are at least as wide as the thickness of said common interior layer.
Claim 6
Dependent Claim 169 words
A symmetrical semiconductor switch comprising: a body formed from at least five layers of alternating first and second types of semiconductor material, said body having first and second outer layers of said first conductivity material, a pair of discrete regions of said first type of semiconductor material formed on said first outer layer, a first groove disposed between said discrete regions such that said regions are on opposite sides of said first groove, a discrete region of said first type of semiconductor material and a region of said second type of semiconductor material formed on said second outer layer, a second groove disposed between said regions on said second outer layer, electrodes contacting said discrete regions to form a three terminal switching device, said grooves having sufficient width and including glass doped with material selected from a group comprising gold and platinum to prevent lateral passage of carriers through the central portion of said body in order to substantially improve the commutating and static dv/dt characteristics of said switch.
Claim 7
Dependent Claim 169 words
A symmetrical semiconductor switch comprising: a body formed from at least five layers of alternating first and second types of semiconductor material, said body having first and second outer layers of said first conductivity material, a pair of discrete regions of said first type of semiconductor material formed on said first outer layer, a first groove disposed between said discrete regions such that said regions are on opposite sides of said first groove, a discrete region of said first type of semiconductor material and a region of said second type of semiconductor material formed on said second outer layer, a second groove disposed between said regions on said second outer layer, electrodes contacting said discrete regions to form a three terminal switching device, said grooves having sufficient width and including glass doped with material selected from a group comprising gold and platinum to prevent lateral passage of carriers through the central portion of said body in order to substantially improve the commutating and static dv/dt characteristics of said switch.
Claim 8
Dependent Claim 22 words
The symmetrical semiconductor switch of claim 5 wherein said grooves are sufficiently wide to degrade the lifetime of carriers passing adjacent thereto.
Claim 9
Dependent Claim 25 words
The symmetrical semiconductor switch of claim 5 wherein said grooves are at least as wide as the thickness of the interior layers adjacent said grooves.

References Cited (Backward Citations)

US3165710A Cited
US3123750A Cited
US3280386A Cited
US3317746A Cited
JPS4425292Y1 Cited
US3524114A Cited
US3549961A Cited
DE2128304A1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-05-02 1980-11-01 1981-05-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-05-02 1984-11-01 1985-05-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-05-02 1988-11-01 1989-05-03 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag