US7049190B2
Expired / Lapsed
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Method for forming ZnO film, method for forming ZnO semiconductor layer, method for fabricating semiconductor device, and semiconductor device
Assignee: Sanyo Electric Co Ltd
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Filing: 2003-03-17
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Granted: 2006-05-23
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Expires: 2023-03-17
Abstract
Abstract A ZnO buffer layer having an electric conductivity of 1×10 −9 S/cm or lower or alternatively a ZnO buffer layer having a diffraction peak of a crystal face other than (002) and (004) in X-ray diffraction is formed on a substrate by sputtering. A ZnO semiconductor layer is formed on the ZnO buffer layer. The ZnO semiconductor layer is formed under the condition that the flow rate ratio of an oxygen gas in a sputtering gas is lower than that in the formation of the ZnO buffer layer.
Inventors
- 👤 Katsutoshi Takeda
- 👤 Masao Isomura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 00:36
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/60; H10D30/67; H10D30/674; H10D30/6755; C; C30; C30B; C30B23/00; C30B23/02; C30B29/00; C30B29/10; C30B29/16; H10D30/6704; H10D30/6713; H10D30/6715; H10D30/6758; H10D62/00; H10D62/80; H10D62/86; H10D99/00; H10P; H10P14/00; H10P14/20; H10P14/22; H10P14/29; H10P14/2901; H10P14/2922; H10P14/32; H10P14/3202; H10P14/3224; H10P14/3226; H10P14/3258; H10P14/34; H10P14/3402; H10P14/3424; H10P14/3426
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
103 words
A method for fabricating a semiconductor device, comprising the steps of: using a non-doped ZnO target and forming a first ZnO film on a substrate by sputtering with a sputtering gas containing oxygen and also forming a second ZnO film on the first ZnO film by sputtering with the flow rate ratio of the oxygen gas in the sputtering gas being decreased continuously; forming a groove dividing the second ZnO film; providing a gate electrode over the groove via an insulating layer; and providing, on the second ZnO film, a source electrode and a drain electrode facing each other with the groove therebetween.
Claim 2
Independent Claim
103 words
A method for fabricating a semiconductor device, comprising the steps of: using a non-doped ZnO target and forming a first ZnO film on a substrate by sputtering with a sputtering gas containing oxygen and also forming a second ZnO film on the first ZnO film by sputtering with the flow rate ratio of the oxygen gas in the sputtering gas being decreased continuously; forming a groove dividing the second ZnO film; providing a gate electrode over the groove via an insulating layer; and providing, on the second ZnO film, a source electrode and a drain electrode facing each other with the groove therebetween.
Claim 3
Dependent Claim
62 words
The method for fabricating a semiconductor device according to claim 1 in which the step for forming a said first ZnO film by sputtering, further comprises: oxygen gas, or a mixture of an inert gas and an oxygen gas as a said sputtering gas; and changing the flow rate ratio of the oxygen gas in the sputtering gas during the film formation.
Claim 4
Dependent Claim
26 words
The method for forming a said first ZnO film according to claim 2 , wherein the flow rate ratio of the oxygen gas is changed continuously.
Claim 5
Dependent Claim
27 words
The method for forming said first ZnO film according to claim 2 , wherein the flow rate ratio of the oxygen gas is increased and decreased alternately.
References Cited (Backward Citations)
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JPH08325711A
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JP2000244014A
Cited
US6448585B1
Cited
JP2001287998A
Cited
US6617183B2
Cited
US20020025594A1
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