US 6,064,086 AGranted

Semiconductor device having lateral IGBT

AssigneeKabushiki Kaisha Toshiba

InventorsAkio Nakagawa, Tomoko Matsudai, Hideyuki Funaki, Norio Yasuhara

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Abstract

An n-type buffer layer and a p-type base layer are formed in the surface of the n.sup.- -type drift layer. A p.sup.+ -type drain layer is formed in the surface of the n-type buffer layer. An n.sup.+ -type source layer and a p.sup.+ -type contact layer are formed in the surface of the p-type base layer. A main gate electrode is arranged to face, through a gate oxide film, a surface of the p-type base layer which is interposed between the n.sup.+ -type source layer and the n.sup.- -type drift layer. An n-type relay layer is formed in the surface of the n.sup.- -type drift layer to face the n.sup.+ -type source layer through the p-type base layer under the main gate electrode. The n-type relay layer extends from the n.sup.- -type drift layer into the p-type base layer. The n-type relay layer decreases the channel resistance.

Claims22

Dependent claims

A semiconductor device having a lateral IGBT, said IGBT comprising:

a drift layer of a first conductivity type formed by using a semiconductor active layer of a high resistivity;
a drain layer of a second conductivity type formed in a common surface of said drift layer;
a base layer of the second conductivity type formed in said common surface of said drift layer;
a source layer of the first conductivity type formed in a surface of said base layer;
a drain electrode arranged in contact with said drain layer;
a source electrode arranged in contact with said source and base layers;
and
a main gate electrode facing, through a gate insulating film, a surface of said base layer which is interposed between said source layer and said drift layer, and is located on a side facing said drain layer,
wherein a relay layer of the first conductivity type having a resistivity lower than that of said drift layer is formed in said common surface of said drift layer to have a facing portion which faces said source layer through said base layer under said main gate electrode, and said relay layer has a surface concentration of an impurity of the first conductivity type which falls within a range of from 2.times.10.sup.16 cm.sup.-3 to 2.times.10.sup.17 cm.sup.-3.

6 more elements

A semiconductor device having a lateral IGBT, said IGBT comprising:

a drift layer of a first conductivity type formed by using a semiconductor active layer of a high resistivity;
a drain layer of a second conductivity type formed in a common surface of said drift layer;
a base layer of the second conductivity type formed in said common surface of said drift layer;
a source layer of the first conductivity type formed in a surface of said base layer;
a drain electrode arranged in contact with said drain layer;
a source electrode arranged in contact with said source and base layers;
and
a main gate electrode facing, through a gate insulating film, a surface of said base layer which is interposed between said source layer and said drift layer, and is located on a side facing said drain layer,
wherein said base layer comprises first and second portions facing each other through an intervening portion which is part of said drift layer,
said source layer comprises first and second portions respectively formed in surfaces of said first and second portions of said base layer,
a sub-gate electrode is arranged to face, through a gate insulating film, a surface of said first portion of said base layer which is interposed between said first portion of said source layer and said intervening portion, and a surface of said second portion of said base layer which is interposed between said second portion of said source layer and said intervening portion, and
further wherein a relay layer of the first conductivity type having a resistivity lower than that of said drift layer is formed in said common surface of said drift layer to have a facing portion which faces said source layer through said base layer under said main gate electrode.

9 more elements

A semiconductor device having a lateral IGBT, said IGBT comprising:

a drift layer of a first conductivity type formed by using a semiconductor active layer of a high resistivity;
a drain layer of a second conductivity type comprising first and second portions formed in a common surface of said drift layer;
a base layer of the second conductivity type formed in said common surface of said drift layer between said first and second portions of said drain layer;
a source layer of the first conductivity type formed in a surface of said base layer;
a drain electrode arranged in contact with said drain layer;
a source electrode arranged in contact with said source and base layers;
and
a main gate electrode comprising first and second portions facing, through a gate insulating film, surfaces of said base layer which are interposed between said source layer and said drift layer, and are located on sides facing said first and second portions of said drain layer, respectively,
wherein said base layer comprises first and second portions facing each other through an intervening portion which is part of said drift layer,
said source layer comprises first and second portions respectively formed in surfaces of said first and second portions of said base layer,
a sub-gate electrode is arranged to face, through a gate insulating film, a surface of said first portion of said base layer which is interposed between said first portion of said source layer and said intervening portion, and a surface of said second portion of said base layer which is interposed between said second portion of said source layer and said intervening portion, and
further wherein a relay layer of the first conductivity type having a resistivity lower than that of said drift layer is formed in said common surface of said drift layer to have first and second facing portions which face said first and second portions of said source layer through said first and second portions of said base layer under said first and second portions of said main gate electrode, respectively.

9 more elements

Dependencies are inferred from the claim text.

Facts

Application: 09/072,460Filed 5 May 1998 · continuation in part
Priority: JP 7-21635024 Aug 1995
Granted: 16 May 2000
Term ends: Not estimatedThe source records don’t support an estimate.

Classification5 codes

H10D 12/01
Bipolar devices controlled by the field effect, e.g. insulated-gate bipolar transistors [IGBT]: manufacture or treatment
H10D 12/421
Insulated-gate bipolar transistors [IGBT]: on insulating layers or insulating substrates, e.g. thin-film IGBTs
H10D 12/491
Vertical IGBTs: having both emitter contacts and collector contacts in the same substrate side
H10D 62/127
Top-view geometrical layouts of the regions or the junctions: of cellular field-effect devices, e.g. multicellular DMOS transistors or IGBTs

Family

Serial701,500Parent of this continuation · filed 22 Aug 1996
Serial970,103Parent of this continuation-in-part · filed 13 Nov 1997
US 5,920,087 AParent of this continuation-in-part
US 5,731,603 AParent of this continuation
US 6,064,086 AThis patent

From the US filing history. Foreign family members aren’t listed.