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US4735824A
Expired / Lapsed
US
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Method of manufacturing an MOS capacitor
Assignee: Toshiba Corp
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Filing: 1986-05-23
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Granted: 1988-04-05
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Expires: 2006-05-23
Abstract
Abstract A method of forming an MOS capacitor by the steps of cutting a groove in the surface of a silicon substrate by the RIE process, thermally oxidizing the surface of said silicon substrate, depositing a capacitor electrode on said capacitor-insulating layer, being characterized in that when the capacitor-insulating layer is deposited, the surface of the silicon substrate is thermally oxidized in an oxidizing atmosphere containing 15% by vol. of steam.
Inventors
- 👤 Kikuo Yamabe
- 👤 Keitaro Imai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:18
CPC Classifications
H; H10; H10B; H10B12/00; H10B12/01; H10B12/02; H10B12/03; H10B12/038; H10D; H10D64/00; H10D64/01; H10D64/013; H10D64/01302; H10D64/01332; H10D64/01336; H10D64/01346
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
120 words
A method of manufacturing an MOS capacitor comprising the steps of: forming a groove in the surface of a silicon substrate; forming an oxide layer on said surface by thermally oxidizing said surface in an oxidizing atmosphere which contains at least one of the groups consisting of steam, chlorine and fluorine; when the atmosphere contains steam, the proportion of said steam ranges between 10 ppm and 30% by vol, and when the atmosphere contains chlorine and/or fluorine, the total proportion of chlorine and/or fluorine ranges between 20 ppm and 10% by vol, whereby a substantially uniform oxide layer is formed on the surface of said groove, including its angular portions; and then fabricating a capacitor electrode on the oxide layer.
Claim 2
Independent Claim
120 words
A method of manufacturing an MOS capacitor comprising the steps of: forming a groove in the surface of a silicon substrate; forming an oxide layer on said surface by thermally oxidizing said surface in an oxidizing atmosphere which contains at least one of the groups consisting of steam, chlorine and fluorine; when the atmosphere contains steam, the proportion of said steam ranges between 10 ppm and 30% by vol, and when the atmosphere contains chlorine and/or fluorine, the total proportion of chlorine and/or fluorine ranges between 20 ppm and 10% by vol, whereby a substantially uniform oxide layer is formed on the surface of said groove, including its angular portions; and then fabricating a capacitor electrode on the oxide layer.
Claim 3
Dependent Claim
33 words
The method according to claim 1, wherein an oxidizing atmosphere for forming said oxide layer composed steam diluted with at least one of the groups consisting of dry oxygen, argon, helium and nitrogen.
Claim 4
Dependent Claim
21 words
The method according to claim 1, wherein the oxide layer is deposited at a temperature ranging from 800° to 1100° C.
Claim 5
Dependent Claim
20 words
The method according to claim 1, wherein said oxide layer is formed with a thickness ranging between 100° and 500°.
Claim 6
Dependent Claim
17 words
The method according to claim 1, wherein said groove is formed by the anisotropic dry etching process.
Claim 7
Dependent Claim
13 words
The method of claim 1 wherein the oxidizing atmosphere contains chlorine and/or fluorine.
Claim 8
Independent Claim
136 words
A method of manufacturing an MOS capacitor which comprises the steps of: forming a groove in the surface of a silicon substrate; forming an oxide layer on said surface by thermally oxidizing said surface in an oxidizing atmosphere which contains at least one of the groups consisting of steam, chlorine and fluorine; when the atmosphere contains steam, the proportion of said steam ranges between 10 ppm and 30% by vol, and when the atmosphere contains chlorine and/or fluorine, the total proportion of chlorine and/or fluorine ranges between 20 ppm and 10% by vol, whereby a substantially uniform oxide layer is formed on the surface of said groove, including its angular portions; removing said thermally oxidized layer; forming a capacitor-insulating layer on the surface of said silicon substrate; and forming a capacitor electrode on said capacitor-insulating layer.
Claim 9
Independent Claim
136 words
A method of manufacturing an MOS capacitor which comprises the steps of: forming a groove in the surface of a silicon substrate; forming an oxide layer on said surface by thermally oxidizing said surface in an oxidizing atmosphere which contains at least one of the groups consisting of steam, chlorine and fluorine; when the atmosphere contains steam, the proportion of said steam ranges between 10 ppm and 30% by vol, and when the atmosphere contains chlorine and/or fluorine, the total proportion of chlorine and/or fluorine ranges between 20 ppm and 10% by vol, whereby a substantially uniform oxide layer is formed on the surface of said groove, including its angular portions; removing said thermally oxidized layer; forming a capacitor-insulating layer on the surface of said silicon substrate; and forming a capacitor electrode on said capacitor-insulating layer.
Claim 10
Dependent Claim
33 words
The method of manufacturing an MOS capacitor according to claim 7, wherein said oxidizing atmosphere comprises stream diluted with at least one of the groups consisting of dry oxygen, argon, helium and nitrogen.
Claim 11
Dependent Claim
26 words
The method of manufacturing an MOS capacitor according to claim 7, wherein said oxide layer is deposited at a temperature ranging between 800° and 1000° C.
Claim 12
Dependent Claim
40 words
The method of manufacturing an MOS capacitor according to claim 7, wherein said thermally oxidized layer is deposited with a thickness greater than 100 Å, and said capacitor-insulating layer is formed with a thickness ranging between 100 and 500 Å.
Claim 13
Dependent Claim
20 words
The method of manufacturing an MOS capacitor according to claim 7, wherein said groove is formed by anisotropic dry etching.
Claim 14
Dependent Claim
29 words
The method of manufacturing an MOS capacitor according to claim 7, wherein the capacitor-insulating layer is formed by thermally oxidizing said silicon substrate in an atmosphere of dry oxygen.
Claim 15
Dependent Claim
37 words
The method of manufacturing an MOS capacitor according to claim 7, wherein the formation of said thermally oxidized layer is preceded by the step of forming a CVD oxidized layer on the surface of said silicon substrate.
Claim 16
Dependent Claim
13 words
The method of claim 7 wherein the oxidizing atmosphere contains chlorine and/or fluorine.
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