US5970384A
Expired / Lapsed
US
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Methods of heat treating silicon oxide films by irradiating ultra-violet light
Assignee: Semiconductor Energy Laboratory Co Ltd
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Filing: 1995-08-02
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Granted: 1999-10-19
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Expires: 2015-08-02
Abstract
Abstract Silicon oxide films which are good as gate insulation films are formed by subjecting a silicon oxide film which has been formed on an active layer comprising a silicon film by means of a PVD method or CVD method to a heat treatment at 300-700 DEG C. in a dinitrogen monoxide atmosphere, or in an NH3 or N2H4 atmosphere, while irradiating with ultraviolet light, reducing the hydrogen and carbon contents in the silicon oxide film and introducing nitrogen into the boundary with the silicon film in particular. Furthermore, silicon oxide films which are good as gate insulating films have been formed by subjecting silicon oxide films which have been formed on an active layer comprising a silicon film by means of a PVD method or CVD method to a heat treatment at 300-700 DEG C. in an N2O atmosphere (or hydrogen nitride atmosphere) while irradiating with ultraviolet light, and then carrying out a heat treatment at 300-700 DEG C. in a hydrogen nitride atmosphere (N2O atmosphere), and reducing the amount of hydrogen and carbon in the silicon oxide film and introducing nitrogen into the boundary with the silicon film in particular.
Inventors
- 👤 Shunpei Yamazaki
- 👤 Yasuhiko Takemura
- 👤 Mitsunori Sakama
- 👤 Tomohiko Sato
- 👤 Satoshi Teramoto
- 👤 Shigefumi Sakai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 06:53
CPC Classifications
H; H10; H10D; H10D64/00; H10D64/01; H10D64/013; H10D64/01302; H10D64/01332; H10P; H10P72/00; H10P72/04; H10P72/0431; C; C23; C23C; C23C14/00; C23C14/58; C23C16/00; C23C16/56; H10D84/00; H10D84/01; H10D84/0123; H10D84/0126; H10D84/0144; H10D84/02; H10D84/03; H10D84/038; H10P14/00; H10P14/60; H10P14/63; H10P14/6326; H10P14/6328; H10P14/6334; H10P72/0402; H10P72/06; H10P72/0602; H10P95/00; H10P95/90; H10D30/00; H10D30/01; H10D30/021; H10D30/031; H10D30/0312; H10D30/0314; H10D30/0321; Y; Y10; Y10S; Y10S438/00; Y10S438/909; Y10S438/91; Y10S438/958
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
88 words
A method of heat treating a silicon oxide film comprising the steps of: forming a silicon oxide film on a surface; introducing dinitrogen monoxide into a chamber in which heat treatment is carried out; and irradiating an ultraviolet light onto the dinitrogen monoxide and a surface of the silicon oxide film at a temperature of 300 to 700° C. in a dinitrogen monoxide atmosphere which has been obtained by means of the introducing step, wherein the surface of the silicon oxide film is nitrided by the irradiating step.
Claim 2
Independent Claim
88 words
A method of heat treating a silicon oxide film comprising the steps of: forming a silicon oxide film on a surface; introducing dinitrogen monoxide into a chamber in which heat treatment is carried out; and irradiating an ultraviolet light onto the dinitrogen monoxide and a surface of the silicon oxide film at a temperature of 300 to 700° C. in a dinitrogen monoxide atmosphere which has been obtained by means of the introducing step, wherein the surface of the silicon oxide film is nitrided by the irradiating step.
Claim 3
Dependent Claim
35 words
The method of claim 1 wherein the silicon oxide film has been formed by means of a plasma CVD method with tetraethoxysilane (TEOS, Si(OC 2 H 5 ) 4 ) as a raw material gas.
Claim 4
Dependent Claim
36 words
The method of claim 1 wherein the silicon oxide film has been formed by means of a low pressure CVD method with monosilane (SiH 4 ) and oxygen gas (O 2 ) as raw material gases.
Claim 5
Dependent Claim
25 words
The method of claim 1 wherein the heating temperature of the silicon oxide film is at least 500° C. and not more than 600° C.
Claim 6
Dependent Claim
25 words
The method of claim 1 wherein the heating time of the silicon oxide film is at least 30 minutes and not more than 6 hours.
Claim 7
Dependent Claim
24 words
The method of claim 1 wherein the substrate temperature is raised and lowered at a rate of 5-30° C./min when carrying out the heating.
Claim 8
Independent Claim
145 words
A method of heat treating a silicon oxide film comprising the steps of: forming a silicon oxide film on a surface; introducing nitrogen into a chamber in which heat treatment is carried out; heating the silicon oxide film at a temperature of at least 300° C. and not more than 700° C. while the silicon oxide film is irradiated with ultraviolet light in a nitrogen atmosphere, introducing dinitrogen monoxide into the chamber after heating the silicon oxide film sufficiently to displace the nitrogen by dinitrogen monoxide; and irradiating an ultraviolet light onto the dinitrogen monoxide and a surface of the silicon oxide film at a temperature of 300 to 700° C. in a dinitrogen monoxide atmosphere obtained by means of the aforementioned steps. wherein the surface of the silicon oxide film is nitrided by the irradiating of the ultraviolet light in the dinitrogen monoxide atmosphere.
Claim 9
Independent Claim
145 words
A method of heat treating a silicon oxide film comprising the steps of: forming a silicon oxide film on a surface; introducing nitrogen into a chamber in which heat treatment is carried out; heating the silicon oxide film at a temperature of at least 300° C. and not more than 700° C. while the silicon oxide film is irradiated with ultraviolet light in a nitrogen atmosphere, introducing dinitrogen monoxide into the chamber after heating the silicon oxide film sufficiently to displace the nitrogen by dinitrogen monoxide; and irradiating an ultraviolet light onto the dinitrogen monoxide and a surface of the silicon oxide film at a temperature of 300 to 700° C. in a dinitrogen monoxide atmosphere obtained by means of the aforementioned steps. wherein the surface of the silicon oxide film is nitrided by the irradiating of the ultraviolet light in the dinitrogen monoxide atmosphere.
Claim 10
Dependent Claim
35 words
The method of claim 7 wherein the silicon oxide film has been formed by means of a plasma CVD method with tetraethoxysilane (TEOS, Si(OC 2 H 5 ) 4 ) as a raw material gas.
Claim 11
Dependent Claim
36 words
The method of claim 7 wherein the silicon oxide film has been formed by means of a low pressure CVD method with monosilane (SiH 4 ) and oxygen gas (O 2 ) as raw material gases.
Claim 12
Dependent Claim
25 words
The method of claim 7 wherein the heating temperature of the silicon oxide film is at least 500° C. and not more than 600° C.
Claim 13
Dependent Claim
25 words
The method of claim 7 wherein the heating time of the silicon oxide film is at least 30 minutes and not more than 6 hours.
Claim 14
Dependent Claim
24 words
The method of claim 7 wherein the substrate temperature is raised and lowered at a rate of 5-30° C./min when carrying out the heating.
Claim 15
Dependent Claim
24 words
The method of claim 7 wherein the heating is carried out in a nitrogen atmosphere when the substrate is being warmed and cooled down.
Claim 16
Independent Claim
114 words
A method of heat treating a silicon oxide film comprising the steps of: forming a silicon oxide film on a surface; introducing dinitrogen monoxide in a chamber in which heat treatment is carried out; irradiating a ultraviolet light onto the dinitrogen monoxide and a surface of the silicon oxide film at a temperature of 300 to 700° C. wherein nitrogen is excited by the ultraviolet light and is kept in an excited state by the ultraviolet light, and the excited nitrogen is diffused into the silicon oxide film by heat attributed to the temperature used in said irradiating step, and wherein the surface of the silicon oxide film is nitrided by the irradiating step.
Claim 17
Independent Claim
114 words
A method of heat treating a silicon oxide film comprising the steps of: forming a silicon oxide film on a surface; introducing dinitrogen monoxide in a chamber in which heat treatment is carried out; irradiating a ultraviolet light onto the dinitrogen monoxide and a surface of the silicon oxide film at a temperature of 300 to 700° C. wherein nitrogen is excited by the ultraviolet light and is kept in an excited state by the ultraviolet light, and the excited nitrogen is diffused into the silicon oxide film by heat attributed to the temperature used in said irradiating step, and wherein the surface of the silicon oxide film is nitrided by the irradiating step.
Claim 18
Dependent Claim
20 words
The method of claim 1 further comprising establishing a vacuum in the chamber before the introducing of the dinitrogen monoxide.
Claim 19
Dependent Claim
20 words
The method of claim 1 wherein the silicon oxide film is formed by a PVD method or a CVD method.
Claim 20
Dependent Claim
20 words
The method of claim 7 wherein the silicon oxide film is formed by a PVD method or a CVD method.
Claim 21
Dependent Claim
20 words
The method of claim 14 wherein the silicon oxide film is formed by a PVD method or a CVD method.
Claim 22
Independent Claim
80 words
A method of heat treating a silicon oxide film comprising the steps of: forming a silicon oxide film on a surface; introducing dinitrogen monoxide into a chamber in which heat treatment is carried out; and irradiating an ultraviolet light onto the dinitrogen monoxide and a surface of the silicon oxide film in a dinitrogen monoxide atmosphere which has been obtained by means of the introducing step, wherein the surface of the silicon oxide film is nitrided by the irradiating step.
Claim 23
Independent Claim
80 words
A method of heat treating a silicon oxide film comprising the steps of: forming a silicon oxide film on a surface; introducing dinitrogen monoxide into a chamber in which heat treatment is carried out; and irradiating an ultraviolet light onto the dinitrogen monoxide and a surface of the silicon oxide film in a dinitrogen monoxide atmosphere which has been obtained by means of the introducing step, wherein the surface of the silicon oxide film is nitrided by the irradiating step.
Claim 24
Dependent Claim
20 words
The method of claim 19 further comprising establishing a vacuum in the chamber before the introducing of the dinitrogen monoxide.
Claim 25
Dependent Claim
20 words
The method of claim 19 wherein the silicon oxide film is formed by a PVD method or a CVD method.
Claim 26
Independent Claim
129 words
A method of heat treating a silicon oxide film comprising the steps of: forming a silicon oxide film on a surface; introducing nitrogen into a chamber in which heat treatment is carried out; heating the silicon oxide film at a temperature of at least 300° C. and not more than 700° C. while the silicon oxide film is irradiated with ultraviolet light in a nitrogen atmosphere, introducing dinitrogen monoxide into the chamber after heating the silicon oxide film sufficiently to displace the nitrogen by dinitrogen monoxide; and irradiating an ultraviolet light onto the dinitrogen monoxide and a surface of the silicon oxide film in a dinitrogen monoxide atmosphere obtained by means of the aforementioned steps, wherein the surface of the silicon oxide film is nitrided by the irradiating step.
Claim 27
Independent Claim
129 words
A method of heat treating a silicon oxide film comprising the steps of: forming a silicon oxide film on a surface; introducing nitrogen into a chamber in which heat treatment is carried out; heating the silicon oxide film at a temperature of at least 300° C. and not more than 700° C. while the silicon oxide film is irradiated with ultraviolet light in a nitrogen atmosphere, introducing dinitrogen monoxide into the chamber after heating the silicon oxide film sufficiently to displace the nitrogen by dinitrogen monoxide; and irradiating an ultraviolet light onto the dinitrogen monoxide and a surface of the silicon oxide film in a dinitrogen monoxide atmosphere obtained by means of the aforementioned steps, wherein the surface of the silicon oxide film is nitrided by the irradiating step.
Claim 28
Dependent Claim
20 words
The method of claim 22 wherein the silicon oxide film is formed by a PVD method or a CVD method.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-10-18 | 2003-04-19 | 2003-10-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-10-18 | 2007-04-19 | 2007-10-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-10-18 | 2011-04-19 | 2011-10-19 | $7700.00 | Window Closed / Lapsed |