EP0171131A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Semiconductor device with MIS capacitor and method of manufacturing the same
Assignee: NTT Inc
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Filing: 1985-03-19
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Granted: —
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Expires: 2005-03-19
Abstract
Abstract @ A semiconductor device with a metal-insulator-semiconductor capacitor has: a semiconductor substrate (11) having a predetermined conductivity type and serving as one electrode of the metal-insulator-semiconductor capacitor, the semiconductor substrate being provided with a trench (13) of a cross-sectionally rectangular shape which extends along a direction of thickness of the semiconductor substrate from a major surface thereof; a doped semiconductor layer (23A) formed along at least side wall surfaces of the trench, the semiconductor layer, which is formed by deposition and etching, being provided with an outer surface, starting to extend in a rounded shape (24A) from major surface portions of the semiconductor substrate and extending substantially parallel to the side wall surfaces of the trench, and a recess, which is defined by the semiconductor layer, having round corners (25) at the bottom; a dielectric insulating layer (27) formed on an exposed surface including the major surface of the semiconductor substrate and the outer surface of the semiconductor layer; and a conductive layer (29) formed on the insulating layer to bury trench and serving as the other electrode.
Inventors
- 👤 Takashi Morie
- 👤 Kazushige Minegishi
- 👤 Shigeru Nakajima
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 02:46
CPC Classifications
H; H10; H10D; H10D1/00; H10D1/60; H10D1/62; H10D1/66; H10D1/665; H10B; H10B12/00; H10B12/30; H10B12/37; Y; Y10; Y10S; Y10S148/00; Y10S148/05
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
171 words
A semiconductor device with a metal-insulator-semiconductor capacitor, comprising: a semiconductor substrate having a predetermined conductivity type and serving as one electrode of said metal-insulator-semiconductor capacitor, said semiconductor substrate being provided with a trench of a cross-sectionally rectangular shape which extends along a direction of thickness of said semiconductor substrate from a major surface thereof; a doped semiconductor layer formed along at least side wall surfaces of said trench, said semiconductor layer, which is formed by deposition and etching, being provided with an outer surface, starting to extend in a rounded shape from major surface portions of said semiconductor substrate and extending substantially parallel to said side wall surfaces of said trench, and a recess, which is defined by said semiconductor layer, having round corners at the bottom; a dielectric insulating layer formed on an exposed surface including said major surface of said semiconductor substrate and said outer surface of said semiconductor layer; and a conductive layer formed on said insulating layer to bury said trench and serving as the other electrode.
Claim 2
Dependent Claim
171 words
A semiconductor device with a metal-insulator-semiconductor capacitor, comprising: a semiconductor substrate having a predetermined conductivity type and serving as one electrode of said metal-insulator-semiconductor capacitor, said semiconductor substrate being provided with a trench of a cross-sectionally rectangular shape which extends along a direction of thickness of said semiconductor substrate from a major surface thereof; a doped semiconductor layer formed along at least side wall surfaces of said trench, said semiconductor layer, which is formed by deposition and etching, being provided with an outer surface, starting to extend in a rounded shape from major surface portions of said semiconductor substrate and extending substantially parallel to said side wall surfaces of said trench, and a recess, which is defined by said semiconductor layer, having round corners at the bottom; a dielectric insulating layer formed on an exposed surface including said major surface of said semiconductor substrate and said outer surface of said semiconductor layer; and a conductive layer formed on said insulating layer to bury said trench and serving as the other electrode.
Claim 3
Dependent Claim
39 words
A device according to claim 1, wherein said semiconductor layer is formed on said side wall surfaces and said bottom of said trench, and said corners of said recess are constituted by said outer surface of said semiconductor layer.
Claim 4
Dependent Claim
21 words
A device according to claim 2, wherein said semiconductor layer has a conductivity type different from that of said semiconductor substrate.
Claim 5
Dependent Claim
45 words
A device according to claim 1, wherein said semiconductor layer is formed only on said side wall surfaces of said trench, and said outer surface of said semiconductor layer continues to said recess formed shallow in said bottom of said trench in said semiconductor substrate.
Claim 6
Dependent Claim
45 words
A device according to claim 1, wherein said semiconductor substrate comprises a p-type silicon, said semiconductor layer comprises an n-type doped polycrystalline silicon and has a thickness smaller than half a width of said trench, and said dielectric insulating layer comprises a silicon oxide layer.
Claim 7
Dependent Claim
37 words
A device according to claim 4, wherein regions are formed adjacent to said major surface of said semiconductor substrate and a surface of said recess and have a conductivity type different from that of said semiconductor substrate.
Claim 8
Dependent Claim
21 words
A device according to claim 1, wherein said dielectric insulating layer comprises a multilayer structure of materials having different dielectric characteristics.
Claim 9
Independent Claim
198 words
A method of manufacturing a semiconductor layer with a metal-insulator-semiconductor capacitor, comprising the steps of: forming a trench of a cross-sectionally rectangular shape in a major surface of a semiconductor substrate which has a predetermined conductivity type and which serves as one electrode of said capacitor; forming a doped semiconductor layer along at least side wall surfaces of said trench, the step of forming said semiconductor layer including the steps of depositing a semiconductor portion so as not to bury said trench with said semiconductor portion and etching at least a part of said semiconductor portion, said semiconductor layer being provided with an outer surface which is formed by deposition and etching, starting to extend in a rounded shape from major surface portions of said semiconductor substrate and extending substantially parallel to said side wall surfaces of-said trench, and a recess, which is defined by said semiconductor layer, having round corners at the bottom; forming a dielectric insulating layer on an exposed surface including said major surface of said semiconductor substrate and said outer surface of said semiconductor layer; and forming a conductive layer on said insulating layer to bury said trench and serving as the other electrode.
Claim 10
Independent Claim
198 words
A method of manufacturing a semiconductor layer with a metal-insulator-semiconductor capacitor, comprising the steps of: forming a trench of a cross-sectionally rectangular shape in a major surface of a semiconductor substrate which has a predetermined conductivity type and which serves as one electrode of said capacitor; forming a doped semiconductor layer along at least side wall surfaces of said trench, the step of forming said semiconductor layer including the steps of depositing a semiconductor portion so as not to bury said trench with said semiconductor portion and etching at least a part of said semiconductor portion, said semiconductor layer being provided with an outer surface which is formed by deposition and etching, starting to extend in a rounded shape from major surface portions of said semiconductor substrate and extending substantially parallel to said side wall surfaces of-said trench, and a recess, which is defined by said semiconductor layer, having round corners at the bottom; forming a dielectric insulating layer on an exposed surface including said major surface of said semiconductor substrate and said outer surface of said semiconductor layer; and forming a conductive layer on said insulating layer to bury said trench and serving as the other electrode.
Claim 11
Dependent Claim
91 words
A method according to claim 8, wherein the step of forming said semiconductor layer includes the steps of: depositing a first doped semiconductor layer on an exposed surface of said major surface of said semiconductor; substrate which includes a surface of said trench; and isotropically etching said first doped semiconductor layer to a predetermined thickness so.as not to expose the surface of said substrate, thereby rounding corners on an outer surface of said first doped semiconductor layer which correspond to said edges defining said trench and said corners of said recess.
Claim 12
Dependent Claim
23 words
A method according to claim 9, wherein the step of forming said trench includes the step of etching damaged layers defining said trench.
Claim 13
Dependent Claim
125 words
A method according to claim 8, wherein the step of forming said semiconductor layer comprises the steps of: depositing a first doped semiconductor layer on an exposed surface of said major surface of said semiconductor substrate which includes a surface of said trench; and isotropically etching said first doped semiconductor layer to form second doped semiconductor layers which are respectively provided with outer surfaces formed by deposition and etching, start in a rounded shape from major surface portions of said semiconductor substrate and extend substantially parallel to said side wall surfaces of said trench, .said major surface portions corresponding to edges defining said trench, and rounding corners of a recess at the bottom of said trench which is defined by said second doped semiconductor layers.
Claim 14
Dependent Claim
42 words
A method according to claim 9, further comprising the step of forming regions which are adjacent to said major surface of said semiconductor substrate and a surface of said recess and have a conductivity type different from that of said semiconductor substrate.
Claim 15
Dependent Claim
26 words
A method according to claim 8, wherein the step of forming said dielectric insulating layer comprises the step of stacking insulating films having different dielectric characteristics.
References Cited (Backward Citations)
EP0030116A2
Cited
WO1981003241A1
Cited
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