Patent EP0219995A2 successfully refreshed from Google Patents.
EP0219995A2
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EP
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Gate turn-off thyristor with independent turn-on/off controlling transistors
Assignee: Toshiba Corp
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Filing: 1986-09-30
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Granted: —
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Expires: 2006-09-30
Abstract
Abstract A gate turn-off thyristor (10) has first and second MOSFETs (Q1, Q2) serving as turn-on and turn-off controlling devices, respectively. A p type semiconductor layer (26a, 26b) is additionally formed in an n type substrate (16) functioning as a first base in such a manner as to overlap a p type second base layer (18). The additional layer (26a, 26b) is different from the second base (18) in impurity concentration, thereby causing the resistivity of the second base (18) to be smaller than that of the additional layer (26a, 26b). The first MOSFET (Q1) has an n type source layer (28) formed in the additional layer (26a) to define a surface portion of the additional layer (26a) positioned between the source layer (28) and the first base layer (16) as a channel region (CH1) of the first MOSFET (Q1). A turn-on gate layer (34) is provided to cover a surface region of the first base (16) and the channel region (CH1) of the first MOSFET (Q1).
Inventors
- 👤 Akio Patent Division K.K. Toshiba Nakagawa
- 👤 Takashi Patent Division K.K. Toshiba Shinohe
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-27 18:17
CPC Classifications
H; H10; H10D; H10D18/00; H10D18/60; H10D18/65; H10D18/655; H10D18/221; H10D18/40
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
288 words
A gate turn-off thyristor (10, 80, 120, 140) having a semiconductive substrate (16) of a first conductivity type serving as a first base layer, wherein first emitter layer (12) and second base layer (18, 82, 126) both of a second conductivity type are formed on opposing surfaces of said substrate (16), said first base layer (16) has a surface region which is in contact with said second base layer (18, 82, 126), and a second emitter layer (20, 84, 122, 158) of the first conductivity type is formed in said second base layer, characterized in that said thyristor comprises: an additional semiconductor layer (26, 86, 126') of the second conductivity type which is formed in said first base layer (16) so as to overlap said second base layer (18, 82, 126) and which is different from said second base layer in an impurity concentration, whereby said second base layer (18, 82, 126) has smaller resistivity than said additional layer a first field effect transistor (Q1, Q3, Q5, Q7) for turning on said thyristor, said first transistor having a source layer (28, 88, 122) formed in said additional layer to define a surface portion of said additional layer positioned between said source layer and said first base layer as a channel region (CH1, CH3, CH5, CH7) of said first transistor, and a first gate layer (34, 90, 128, 142) insulatively provided above said substrate to at least partially cover the surface region of said first base layer and the channel region of said first transistor; and a second field effect transistor (Q2, Q4, Q6, Q8) for short-circuiting said first base layer and said second emitter layer with each other to thereby turn off said thyristor (10, 80, 120, 140).
Claim 2
Dependent Claim
288 words
A gate turn-off thyristor (10, 80, 120, 140) having a semiconductive substrate (16) of a first conductivity type serving as a first base layer, wherein first emitter layer (12) and second base layer (18, 82, 126) both of a second conductivity type are formed on opposing surfaces of said substrate (16), said first base layer (16) has a surface region which is in contact with said second base layer (18, 82, 126), and a second emitter layer (20, 84, 122, 158) of the first conductivity type is formed in said second base layer, characterized in that said thyristor comprises: an additional semiconductor layer (26, 86, 126') of the second conductivity type which is formed in said first base layer (16) so as to overlap said second base layer (18, 82, 126) and which is different from said second base layer in an impurity concentration, whereby said second base layer (18, 82, 126) has smaller resistivity than said additional layer a first field effect transistor (Q1, Q3, Q5, Q7) for turning on said thyristor, said first transistor having a source layer (28, 88, 122) formed in said additional layer to define a surface portion of said additional layer positioned between said source layer and said first base layer as a channel region (CH1, CH3, CH5, CH7) of said first transistor, and a first gate layer (34, 90, 128, 142) insulatively provided above said substrate to at least partially cover the surface region of said first base layer and the channel region of said first transistor; and a second field effect transistor (Q2, Q4, Q6, Q8) for short-circuiting said first base layer and said second emitter layer with each other to thereby turn off said thyristor (10, 80, 120, 140).
Claim 3
Dependent Claim
79 words
The thyristor according to claim 1, characterized in that said second base layer (18, 82, 126) comprises a surface region interposed between said additional semiconductor layer (26, 86, 126') and said second emitter layer (20, 84, 122, 158) , and that said second transistor (Q2, Q4, Q6, Q8) comprises a second gate layer (50, 56; 110, 112; 134, 136) insulatively formed on said substrate to at least cover the surface region of said second base layer (18, 82, 126).
Claim 4
Dependent Claim
70 words
The thyristor according to claim 2, characterized in that said first and second transistors (Q1, Q5; Q2, Q6) have the same channel types, and that said second transistor (Q2, Q6) comprises a drain layer (30, 40; 132) which is formed in said second base layer and defines a surface region of said second base layer disposed between itself and said second emitter layer as the channel of said second transistor.
Claim 5
Dependent Claim
45 words
The thyristor according to claim 3, characterized in that said second gate layer (50, 56; 134) is formed to cover a portion of the surface region of said second base layer disposed between said drain layer and said second emitter layer of said second transistor.
Claim 6
Dependent Claim
45 words
The thyristor according to claim 4, characterized in that the source layer (28, 122) of said first transistor and the drain layer (30, 40; 132) of said second transistor are formed of first conductivity type semiconductor diffusion layers electrically connected to said second base layer.
Claim 7
Dependent Claim
39 words
The thyristor according to claim 5, characterized by further comprising a conductive layer (32) formed on said additional layer (26a, 26b) to connect said source layer (28) and said drain layer (30, 40) to said second base layer (18).
Claim 8
Dependent Claim
91 words
The thyristor according to claim 5, characterized in that said second emitter layer (20) at least partially has a substantially rectangular slender planar shape defined by long and short sides, the source layer (28) of said first transistor (Q1) is extended substantially parallel to the short sides of said second emitter (20), and the drain layer (30) of said second transistor (Q2) is extended substantially parallel to the long sides of said second emitter, whereby said second transistor (Q2) comprises a channel width longer than that of said first transistor (Q1).
Claim 9
Dependent Claim
96 words
The thyristor according to claim 2, characterized in that said first and second transistors (Q3, Q7; Q4, Q8) have different channel types, that said second transistor (Q4, Q8) has a second conductivity type source layer (100; 148, 150) which is formed in said second emitter layer (84, 122) to define a surface region of said second emitter layer disposed between itself and said second base layer (82, 126) as the channel of the second transistor, and that said second gate layer (110, 122; 142) being formed to cover said surface region of said second emitter layer.
Claim 10
Dependent Claim
65 words
The thyristor according to claim 8, characterized in that the source layer (88) of said first transistor (Q3) is formed of a first conductivity type semiconductor diffusion layer electrically connected to said second base layer (82), and that the source layer (100) of said second transistor (Q4) is formed of a second conductivity type semiconductor diffusion layer electrically connected to said second emitter layer (84).
Claim 11
Dependent Claim
78 words
The thyristor according to claim 9, characterized by further comprising: a first conductive layer (94) formed on said additional layer to connect the source layer (88) of said first transistor to said second base layer (82); and a second conductive layer (104) formed on said second emitter layer to connect the source layer (100) of said second transistor (Q4) to the second emitter layer (84), said second conductive layer functioning as the cathode (C) electrode of said thyristor.
Claim 12
Dependent Claim
35 words
The thyristor according to claim 10, characterized in that said first and second gate layers (90; 110, 112) are electrically connected to commonly receive a voltage for controlling the turn-on and off of said thyristor.
Claim 13
Dependent Claim
89 words
The thyristor according to claim 10, characterized in that said second emitter layer (84) at least partially comprises a substantially rectangular slender planar shape defined by long and short sides, the source layer (88) of said first transistor (Q3) is extended substantially parallel to the short sides of said second emitter layer, and the source layer (100) of said second transistor is extended substantially parallel to the long sides of said second emitter layer, whereby said second transistor has a channel width longer than that of said first transistor.
Claim 14
Dependent Claim
144 words
A gate turn-off thyristor (10, 80, 120, 140) having a semiconductive substrate (16) of a first conductivity type serving as a first base layer, first emitter layer (12) and second base layer (18, 82, 126) both of a second conductivity type, which are formed on opposing surfaces of said substrate (16), and a second emitter layer (20, 84, 122, 158) of the first conductivity type formed in said second base layer, characterized in that said thyristor comprises: a first field effect transistor (Q1, Q3, Q5, Q7) switched for driving on said thyristor, said first transistor having a channel width of first length; and a second field effect transistor (Q2, Q4, Q6, Q8) switched for driving off said thyristor by short-circuiting said first base layer and said second emitter layer, said second transistor having a channel length of second length longer than said first length.
Claim 15
Dependent Claim
144 words
A gate turn-off thyristor (10, 80, 120, 140) having a semiconductive substrate (16) of a first conductivity type serving as a first base layer, first emitter layer (12) and second base layer (18, 82, 126) both of a second conductivity type, which are formed on opposing surfaces of said substrate (16), and a second emitter layer (20, 84, 122, 158) of the first conductivity type formed in said second base layer, characterized in that said thyristor comprises: a first field effect transistor (Q1, Q3, Q5, Q7) switched for driving on said thyristor, said first transistor having a channel width of first length; and a second field effect transistor (Q2, Q4, Q6, Q8) switched for driving off said thyristor by short-circuiting said first base layer and said second emitter layer, said second transistor having a channel length of second length longer than said first length.
Claim 16
Dependent Claim
76 words
The thyristor according to claim 13, characterized in that said second emitter layer (20, 84, 122, 158) at least partially has a substantially rectangular slender planar shape defined by long and short sides, said first transistor comprises a channel region (CH1, CH3, CH5, CH7) formed long the short sides of said second emitter layer, and said second transistor comprises a channel region (CH2, CH4, CH6, CH8) formed along the long sides of said second emitter layer.
Claim 17
Dependent Claim
37 words
The thyristor according to claim 14, characterized in that said second emitter layer (20, 84, 122) is formed in said second base layer and divided into a plurality of semiconductor layers having a rectangular slender planar shape.
Claim 18
Dependent Claim
42 words
The thyristor according to claim 14, characterized in that said second emitter layer (158) is formed in said second base layer and is formed of a first conductivity type semiconductor layer having a plurality of layer portions of rectangular slender planar shape.
References Cited (Backward Citations)
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