US5208174A
Expired / Lapsed
US
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Method for manufacturing a nonvolatile semiconductor memory device
Assignee: Toshiba Corp
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Filing: 1991-07-03
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Granted: 1993-05-04
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Expires: 2011-07-03
Abstract
Abstract According to a method for manufacturing a nonvolatile semiconductor memory device, first, a CVD oxidation film is formed in a side wall portion of a floating gate formed on a semiconductor substrate. Then, a thermal oxidation film is formed between said floating gate and said CVD oxidation film by a thermal oxidation method. Additionally, before forming said CVD oxidation film, a thermal oxidation film may be formed in the side portion of said floating gate.
Inventors
- 👤 Seiichi Mori
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 02:42
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/01; H10D30/021; H10D30/0411; H10D64/00; H10D64/01; H10D64/031; H10D64/035; H10B; H10B69/00
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
73 words
A method for manufacturing a nonvolatile semiconductor memory device having a floating gate transistor in an element region on a major surface of a body of semiconductor material, the method comprising the steps of: depositing a first oxidation film on a side wall portion of a floating gate of said floating gate transistor using a CVD method; and subsequently forming a second oxidation film between said floating gate and said first oxidation film.
Claim 2
Independent Claim
73 words
A method for manufacturing a nonvolatile semiconductor memory device having a floating gate transistor in an element region on a major surface of a body of semiconductor material, the method comprising the steps of: depositing a first oxidation film on a side wall portion of a floating gate of said floating gate transistor using a CVD method; and subsequently forming a second oxidation film between said floating gate and said first oxidation film.
Claim 3
Dependent Claim
34 words
The method for manufacturing a nonvolatile semiconductor memory device according to claim 1, wherein said first oxidation film is formed by decomposing Si(OC 2 H 5 ) 4 at temperature of about 700° C.
Claim 4
Dependent Claim
39 words
The method for manufacturing a nonvolatile semiconductor memory device according to claim 1, wherein said first oxidation film is formed by reacting SiCl 2 H 2 and N 2 O with each other at temperature of about 900° C.
Claim 5
Dependent Claim
23 words
The method for manufacturing a nonvolatile semiconductor memory device according to claim 1, wherein said first oxidation film does not include impurity material.
Claim 6
Dependent Claim
30 words
The method for manufacturing a nonvolatile semiconductor memory device according to claim 1, wherein said first oxidation film includes impurity material whose concentration is below 1×10 21 cm -3 .
Claim 7
Independent Claim
91 words
A method for manufacturing a nonvolatile semiconductor memory device having a floating gate transistor in an element region on a major surface of a body of semiconductor material, the method comprising the steps of: forming a first oxidation film on a side wall portion of a floating gate of said floating gate transistor using a thermal oxidation method; depositing a second oxidation film on the side wall portion of said floating gate using a CVD method; subsequently forming a third oxidation film between said floating gate and said second oxidation film.
Claim 8
Independent Claim
91 words
A method for manufacturing a nonvolatile semiconductor memory device having a floating gate transistor in an element region on a major surface of a body of semiconductor material, the method comprising the steps of: forming a first oxidation film on a side wall portion of a floating gate of said floating gate transistor using a thermal oxidation method; depositing a second oxidation film on the side wall portion of said floating gate using a CVD method; subsequently forming a third oxidation film between said floating gate and said second oxidation film.
Claim 9
Dependent Claim
34 words
The method for manufacturing a nonvolatile semiconductor memory device according to claim 6, wherein said second oxidation film is formed by decomposing Si(OC 2 H 5 ) 4 at temperature of about 700° C.
Claim 10
Dependent Claim
39 words
The method for manufacturing a nonvolatile semiconductor memory device according to claim 6, wherein said second oxidation film is formed by reacting SiCl 2 H 2 and N 2 O with each other at temperature of about 900° C.
Claim 11
Dependent Claim
23 words
The method for manufacturing a nonvolatile semiconductor memory device according to claim 6, wherein said second oxidation film does not include impurity material.
Claim 12
Dependent Claim
30 words
The method for manufacturing a nonvolatile semiconductor memory device according to claim 6, wherein said second oxidation film includes impurity material whose concentration is below 1×10 21 cm -3 .
Claim 13
Independent Claim
92 words
A method for manufacturing a non-volatile semiconductor memory device, the method comprising the steps of: forming a first gate electrode insulatively spaced from a major surface of a body of semiconductor material and a second gate electrode superposed on and insulatively spaced from said first gate electrode; depositing a first oxidation film on said first and second gate electrodes; and thermally oxidizing a resultant structure to round edges of said first gate electrode and thereby forming a second oxidation film between said first oxidation film and said first and second gate electrodes.
Claim 14
Independent Claim
92 words
A method for manufacturing a non-volatile semiconductor memory device, the method comprising the steps of: forming a first gate electrode insulatively spaced from a major surface of a body of semiconductor material and a second gate electrode superposed on and insulatively spaced from said first gate electrode; depositing a first oxidation film on said first and second gate electrodes; and thermally oxidizing a resultant structure to round edges of said first gate electrode and thereby forming a second oxidation film between said first oxidation film and said first and second gate electrodes.
Claim 15
Dependent Claim
29 words
The method according to claim 11, wherein the step of depositing a first oxidation film comprises depositing a first oxidation film by a low pressure chemical vapor deposition method.
Claim 16
Dependent Claim
30 words
The method according to claim 11, wherein the step of depositing a first oxidation film comprises: decomposing Si(OC 2 H 5 ) 4 at a temperature of about 700° C.
Claim 17
Dependent Claim
25 words
The method according to claim 11, wherein the step of depositing a first oxidation film comprises: reacting SiCl 2 H 2 with N 2 O.
Claim 18
Dependent Claim
28 words
The method according to claim 11, wherein the step of thermally oxidizing a resultant structure comprises thermally oxidizing a resultant structure in an ambient atmosphere of oxygen gas.
Claim 19
Dependent Claim
25 words
The method according to claim 15, wherein the step of thermally oxidizing a resultant structure is carried out at a temperature of about 900° C.
Claim 20
Dependent Claim
19 words
The method according to claim 11, wherein the first oxidation film is deposited to a thickness of 400 Ångstroms.
Claim 21
Dependent Claim
32 words
The method according to claim 11, further comprising the step of: thermally oxidizing said first and second gate electrodes to form a thermal oxidation film prior to depositing said first oxidation film.
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