EP0008535A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
A gate controlled semiconductor device
Assignee: Meidensha Corp
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Filing: 1979-08-20
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Granted: —
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Expires: 1999-08-20
Abstract
Abstract A gate controlled semiconductor device comprises a semiconductor element (1) of a wafer of semiconductor material having four layers (P I , N 1 , P 2 , N 2 ) of alternate conductivity types defining three series arranged junctions, a cathode electrode divided into a plurality of cathode electrode assemblies (K) including a metallic layer (11) deposited on a cathode-emitter layer (5), formed on a surface of said semiconductor element (1 an anode electrode assembly (A), at least one gate electrode assembly (G,, G 2 ) for supplying an OFF signal to said semiconductor element (1), and impedance adjusting means for changing the turn-off time of the main current of said semiconductor element (1) and for equalizing the impedance of current paths between at least one drain (9, 18) of said gate assembly (G 1 , G 2 ) and said cathode-emitter layer (5).
Inventors
- 👤 Tetsuro Sueoka
- 👤 Satoshi Ishibashi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 17:25
CPC Classifications
H; H10; H10D; H10D62/00; H10D62/10; H10D62/13; H10D62/141; H10D62/142; H10D18/00; H10D18/60; H10D62/17; H10D62/192; H10D62/206; H10D64/00; H10D64/20; H10D64/27; H10D64/291
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
112 words
A gate controlled scmiconductor device comprising a semiconductor wafer element of semiconductor material having four layers of alternate conductivity types defining three series arranged junctions, a cathode electrode divided into a plurality of cathode electrode assemblies, each assembly including a metallic layer formed on a surface of said semiconductor clement, an anode electrode, a gate electrode assembly including a drain electrode for supplying an OFF sigal to said semiconductor element, impedance adjusting means for changing the turn-off time of the main current of said semiconductor element, and means for equalizing the impedance of current paths between the drain electrode of the gate electrode assembly and a cathode-emitter layer of the semiconductor element.
Claim 2
Dependent Claim
112 words
A gate controlled scmiconductor device comprising a semiconductor wafer element of semiconductor material having four layers of alternate conductivity types defining three series arranged junctions, a cathode electrode divided into a plurality of cathode electrode assemblies, each assembly including a metallic layer formed on a surface of said semiconductor clement, an anode electrode, a gate electrode assembly including a drain electrode for supplying an OFF sigal to said semiconductor element, impedance adjusting means for changing the turn-off time of the main current of said semiconductor element, and means for equalizing the impedance of current paths between the drain electrode of the gate electrode assembly and a cathode-emitter layer of the semiconductor element.
Claim 3
Dependent Claim
75 words
A gate controlled semiconductor device as claimed in claim 1 wherein said impedance adjusting means comprises a plurality of gate electrode assemblies, a plurality of cathode electrode assemblies facing said gate electrede assemblies, said electrode assemblies being so formed that each drain electrode has a base portion and an end portion and the width of the end portion of each drain electrode of said gate electrode assembly is less than that of the base portion.
Claim 4
Dependent Claim
41 words
A gate controlled semiconductor device as claimed in claim 2 wherein said gate electrode assembly comprises a plurality of low resistance radial fingers provided in a layer of the semiconductor element and an electrode assembly connected to said low resistance layer.
Claim 5
Dependent Claim
44 words
A gate controlled semiconductor device as claimed in claim 2 wherein said gate electrode assembly includes a plurality of circular-shaped low resistance rings concentrically arranged in a layer of the semiconductor element, and a plurality of involute-shaped low resistance fingers provided in said layer.
Claim 6
Dependent Claim
48 words
A gate controlled semiconductor device as claimed in claim 1 wherein said impedance adjusting means comprises a plurality of short-circuiting projections located in a P-type layer and arranged in circles, the concentration thereof increasing in the portion situated far from the drain terminal of said gate electrode assembly.
Claim 7
Dependent Claim
58 words
A gate controlled semiconductor device as claimed in claim 1 wherein said impedance adjusting means includes a gate electrode assembly, a gold-doped base layer provided in the said semiconductor element so that the impurity concentration of the diffused gold layer increases in the portion of the base layer far from the drain terminal of said gate electrode assembly.
References Cited (Backward Citations)
No citation records indexed.
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