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EP0344863A1
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A method of producing a thin film transistor
Assignee: Imec
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Filing: 1989-05-30
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Granted: —
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Expires: 2009-05-30
Abstract
Abstract A thin film transistor (2) is produced by applying onto a non-silicon foundation (1), a thin film of silicon semiconductor material (8) under such conditions that polycrystalline or microcrystalline material is formed. Source (3) and/or drain (4) regions of doped semiconductor material are then formed onto the film; following by applying insulating material (9) onto the film, and a gate region onto the insulating material. The source and/or drain regions are applied so that such regions have a crystalline structure that depends upon the crystalline structure of the underlying thin film. The resulting source and drain regions have high lateral conductivity so that source and drain contacts (5,6) can be made with reduced cross-sectional areas. The method may employ a self-alignment process to simplify device production.
Inventors
- 👤 Kazuhiro Kobayashi
- 👤 Kris August Emilia Ferdinand Baert
- 👤 Johan Francis Albert Nijs
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 15:24
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/60; H10D30/67; H10D30/01; H10D30/021; H10D30/031; H10D30/0312; H10D30/0314; H10D30/0321; H10P; H10P14/00; H10P14/20; H10P14/24; H10P14/29; H10P14/2901; H10P14/2921; H10P14/34; H10P14/3402; H10P14/3404; H10P14/3411; Y; Y10; Y10S; Y10S148/00; Y10S148/122
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
87 words
A method of producing a thin film transistor, comprising: applying onto a non-silicon foundation a thin film of silicon semiconductor material under such conditions that polycrystalline or microcrystalline material is formed; applying source and/or drain regions of doped semi-conductor material onto said film; applying insulating material onto said film; and applying a gate region onto said insulating material; wherein said source and/or drain regions are applied such that said source and/or drain regions have a crystalline structure that depends upon tne crystalline structure of said thin film.
Claim 2
Independent Claim
87 words
A method of producing a thin film transistor, comprising: applying onto a non-silicon foundation a thin film of silicon semiconductor material under such conditions that polycrystalline or microcrystalline material is formed; applying source and/or drain regions of doped semi-conductor material onto said film; applying insulating material onto said film; and applying a gate region onto said insulating material; wherein said source and/or drain regions are applied such that said source and/or drain regions have a crystalline structure that depends upon tne crystalline structure of said thin film.
Claim 3
Dependent Claim
31 words
A method according to claim 1, in which said source and/or drain regions are applied in a Plasma Enhanced Chemical Vapour Deposition process in which PECVD process halogen ions are present.
Claim 4
Dependent Claim
27 words
A method according to claim 2 further comprising the step of subjecting said film to a HF dip prior to introducing said film into a PECVD apparatus.
Claim 5
Dependent Claim
37 words
A method according to claim 3, in which said source and/or drain regions are applied under conditions for depositing amorphous silicon on a non-silicon substrate, after which the so-formed structure is annealed for a predetermined time period.
Claim 6
Dependent Claim
25 words
A method according to claim 3, in which said source and/or drain regions are applied under conditions for depositing microcrystalline material on a non-silicon substrate.
Claim 7
Dependent Claim
36 words
A method according to claim 2, in which said source and/or drain regions are applied in a PECVD apparatus under microcrystalline conditions and in which SiH n F 4-n (n=0,1,2,3) is introduced in the PECVD apparatus.
Claim 8
Dependent Claim
20 words
A method according to claim 5 or 6, in which the so-formed structure is annealed for a predetermined time period.
Claim 9
Dependent Claim
16 words
A method according to claim 4, in which annealing is performed at a temperature under 700°C,
Claim 10
Independent Claim
32 words
A method according to any one of the claims 2-6, in which one or more etching gasses are present in the PECVD process during the time period during which deposition is executed.
Claim 11
Dependent Claim
13 words
A method according to claim 9, in which the etching gas is SiF₄.
Claim 12
Dependent Claim
15 words
A thin film transistor produced by a method according to any of the claims 1-6.
Claim 13
Dependent Claim
40 words
A thin film transistor comprising a thin film of silicon semi-conductor material in polycrystalline or micro crystalline form, having doped source and/or drain regions, of which the crystalline structure is dependent upon th crystalline structure of said thin film .
Claim 14
Dependent Claim
40 words
A thin film transistor comprising a thin film of silicon semi-conductor material in polycrystalline or micro crystalline form, having doped source and/or drain regions, of which the crystalline structure is dependent upon th crystalline structure of said thin film .
Claim 15
Dependent Claim
27 words
A thin film transistor according to claim 12, in which source and drain regions have a conductivity greater than or equivalent to approx. 5 mhos per cm.
Claim 16
Dependent Claim
38 words
A thin film transistor according to claim 12 or 13, comprising source and/or drain contacts to said drain and/or source regions respectively, which have a smaller cross section than the cross section of said source and/or drain regions.
References Cited (Backward Citations)
EP0062079A1
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US4625224A
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US4485121A
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GB2156385A
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EP0232619A2
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