Patent EP0139019A1 successfully refreshed from Google Patents.
EP0139019A1
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EP
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Semiconductor device and method of manufacture thereof
Assignee: Hitachi Ltd
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Filing: 1984-03-26
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Granted: —
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Expires: 2004-03-26
Abstract
Abstract A semiconductor device is provided with a bipolar element and MOSfield-effect transistors formed on one surface of a semiconductorsubstrate. A first buried layer of a first conductivity type is formed in a region of the semiconductor substrate in which the bipolar element and at least one of the MOS field-effect transistors are formed. A second buried layer of the first conductivity type is formed in a portion of the semiconductor substrate corresponding to at least the emitter of the bipolar element. The depth from the surface of the semiconductor substrate to the second buried layer is less than the depth from that surface to the first buried layer. This makes it possible to prevent any increase in the capacity of the MOS field-effect transistors, and increase the operating speed of the bipolar element.
Inventors
- 👤 Takahide Ikeda
- 👤 Atsuo Watanabe
- 👤 Touji Mukai
- 👤 Masanori Odaka
- 👤 Katsumi Ogiue
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 03:33
CPC Classifications
H; H10; H10D; H10D84/00; H10D84/01; H10D84/0107; H10D84/0109; H10W; H10W15/00; H10D84/0123; H10D84/0126; H10D84/0165; H10D84/02; H10D84/03; H10D84/038; H10D84/40; H10D84/401; H10D84/80; H10D84/82; H10D84/83; H10D84/85; H10W15/01
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
116 words
In a semiconductor device of the type in which a bipolar element and MOS field-effect transistors are formed on one surface of a semiconductor substrate, the improvement wherein first buried layers of a first conductivity type are formed in regions in which said bipolar element and at least one of said MOS field-effect transistors are formed, a second buried layer of said first conductivity type is formed within said semiconductor substrate, facing the emitter of said bipolar element, and the depth from said surface of said semiconductor substrate to said second buried layer of said first conductivity type is less than the depth from said surface to said first buried layer of said first conductivity type.
Claim 2
Dependent Claim
116 words
In a semiconductor device of the type in which a bipolar element and MOS field-effect transistors are formed on one surface of a semiconductor substrate, the improvement wherein first buried layers of a first conductivity type are formed in regions in which said bipolar element and at least one of said MOS field-effect transistors are formed, a second buried layer of said first conductivity type is formed within said semiconductor substrate, facing the emitter of said bipolar element, and the depth from said surface of said semiconductor substrate to said second buried layer of said first conductivity type is less than the depth from said surface to said first buried layer of said first conductivity type.
Claim 3
Dependent Claim
71 words
The semiconductor device as defined in claim 1, wherein said second buried layer of said first conductivity type is formed within said semiconductor substrate, facing the gate of one of said MOS field-effect transistors, and the depth from said surface of said substrate to said second buried layer of said first conductivity type is less than the depth from said surface to said first buried layer of said first conductivity type.
Claim 4
Dependent Claim
100 words
The semiconductor device as defined in claim 1 or 2 wherein first buried layers of a second conductivity type are formed within the regions of said semiconductor substrate at which at least one of said MOS field-effect transistors is formed, a second buried layer of said second conductivity type is formed within said semiconductor substrate facing the gate of said MOS field-effect transistor, and the depth from said surface of said substrate to said second buried layer of said second conductivity type is less than the depth from said surface to said first buried layer of said second conductivity type.
Claim 5
Dependent Claim
175 words
In a method of producing a semiconductor device provided with a bipolar element and a MOS field-effect transistor on one surface of a semiconductor substrate, the improvement comprising the steps of: forming a plurality of first buried layers of a high concentration of an impurity of a first conductivity type on one surface of a semiconductor substrate of a predetermined conductivity type; forming a second buried layer of a high concentration of an impurity of said first conductivity type which has a coefficient of diffusion greater than that of said high-concentration impurity of said first buried layer, within at least one of said first buried layers; forming an epitaxial layer of said first conductivity type over said semiconductor substrate including said first and second buried layers; and forming said bipolar element and said MOS field-effect transistor on one surface of said epitaxial layer corresponding to said first buried layer, and forming an emitter layer of said bipolar element on said surface of said epitaxial layer corresponding to at least one of said second buried layers.
Claim 6
Dependent Claim
175 words
In a method of producing a semiconductor device provided with a bipolar element and a MOS field-effect transistor on one surface of a semiconductor substrate, the improvement comprising the steps of: forming a plurality of first buried layers of a high concentration of an impurity of a first conductivity type on one surface of a semiconductor substrate of a predetermined conductivity type; forming a second buried layer of a high concentration of an impurity of said first conductivity type which has a coefficient of diffusion greater than that of said high-concentration impurity of said first buried layer, within at least one of said first buried layers; forming an epitaxial layer of said first conductivity type over said semiconductor substrate including said first and second buried layers; and forming said bipolar element and said MOS field-effect transistor on one surface of said epitaxial layer corresponding to said first buried layer, and forming an emitter layer of said bipolar element on said surface of said epitaxial layer corresponding to at least one of said second buried layers.
Claim 7
Dependent Claim
40 words
The method of producing a semiconductor device as defined in claim 4, wherein the gate of said M OS field-effect transistor is formed on said surface of said epitaxial layer corresponding to at least one of said second buried layers.
References Cited (Backward Citations)
No citation records indexed.
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