US5512494A
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Method for manufacturing a thin film transistor having a forward staggered structure
Assignee: Vista Peak Ventures LLC
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Filing: 1994-11-29
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Granted: 1996-04-30
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Expires: 2014-11-29
Abstract
Abstract A thin film transistor having a staggered structure and manufactured by the method of the invention comprises a first amorphous silicon film of a uniform thickness including source and drain regions, a second amorphous semiconductor film acting as a channel layer, a gate insulating film and a gate electrode laminated on a glass substrate in this order. An interface between the semiconductor film and the gate insulating film is formed flat from the source region to the drain region through a channel region. The thin film transistor formed in a staggered structure features a uniform drain current distribution and a high carrier mobility which improve current drivability and LCD image quality when used in a LCD.
Inventors
- 👤 Hiroshi Tanabe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 09:49
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/60; H10D30/67; H10D30/6704; H10D30/6725; H10D30/6713; H10D30/6729; H10D30/673; H10D30/6731; H10D30/674; H10D30/6741; H10D30/6743; H10D30/6745
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
105 words
A method for forming a semiconductor device, including the steps of: forming on an insulating surface of a substrate a first semiconductor film including a source region and a drain region, said first semiconductor film having a substantially uniform thickness; forming a second semiconductor film on said first semiconductor film without etching a region of said first semiconductor film between the source region and the drain region; irradiating a laser beam onto said second semiconductor film to anneal said second semiconductor film; and forming consecutively a gate insulating film and a gate electrode on said second semiconductor film after said irradiating by said laser beam.
Claim 2
Independent Claim
105 words
A method for forming a semiconductor device, including the steps of: forming on an insulating surface of a substrate a first semiconductor film including a source region and a drain region, said first semiconductor film having a substantially uniform thickness; forming a second semiconductor film on said first semiconductor film without etching a region of said first semiconductor film between the source region and the drain region; irradiating a laser beam onto said second semiconductor film to anneal said second semiconductor film; and forming consecutively a gate insulating film and a gate electrode on said second semiconductor film after said irradiating by said laser beam.
Claim 3
Dependent Claim
43 words
A method for forming a semiconductor device as defined in claim 1 wherein said forming of said first semiconductor film includes a step of introducing oxygen ions into a region of said first semiconductor film between said source region and said drain region.
Claim 4
Dependent Claim
35 words
A method for forming a semiconductor device as defined in claim 1 wherein said forming of said first semiconductor film includes a step of implanting impurity ions to said source region and said drain region.
Claim 5
Dependent Claim
20 words
A method for forming a semiconductor device as defined in claim 1 wherein said laser beam is an excimer laser.
Claim 6
Dependent Claim
23 words
A method for forming a semiconductor device as defined in claim 1 wherein said first semiconductor film is formed in an amorphous state.
Claim 7
Dependent Claim
36 words
A method for forming a semiconductor device as defined in claim 1, wherein said second semiconductor film is formed in an amorphous state and annealed to a polycrystalline state by said irradiating of the laser beam.
Claim 8
Dependent Claim
35 words
A method for forming a semiconductor device as defined in claim 6, including a step of introducing oxygen ions into a region of said first semiconductor film between said source region and said drain region.
Claim 9
Dependent Claim
19 words
A method for forming a semiconductor device as defined in claim 1 wherein said substrate is an SOI substrate.
Claim 10
Dependent Claim
18 words
A method for forming a semiconductor device as defined claim 1 wherein said substrate is an insulator substrate.
Claim 11
Independent Claim
109 words
A method for forming a semiconductor device including the steps of: forming on an insulating surface of a substrate a metal pattern layer acting as electrodes for a source region and a drain region; forming over said metal pattern layer a first semiconductor film including a source region and a drain region, said first semiconductor film having a substantially uniform thickness; forming a second semiconductor film on said first semiconductor film; irradiating a laser beam onto said second semiconductor film to anneal said second semiconductor film; and forming, consecutively, a gate insulating film and a gate electrode on said second semiconductor film after said irradiating by said laser beam.
Claim 12
Independent Claim
109 words
A method for forming a semiconductor device including the steps of: forming on an insulating surface of a substrate a metal pattern layer acting as electrodes for a source region and a drain region; forming over said metal pattern layer a first semiconductor film including a source region and a drain region, said first semiconductor film having a substantially uniform thickness; forming a second semiconductor film on said first semiconductor film; irradiating a laser beam onto said second semiconductor film to anneal said second semiconductor film; and forming, consecutively, a gate insulating film and a gate electrode on said second semiconductor film after said irradiating by said laser beam.
Claim 13
Dependent Claim
35 words
A method for forming a semiconductor device as defined in claim 10 wherein said forming of said first semiconductor film includes a step of implanting impurity ions to said source region and said drain region.
Claim 14
Dependent Claim
23 words
A method for forming a semiconductor device as defined in claim 10 wherein said first semiconductor film is formed in an amorphous state.
Claim 15
Dependent Claim
36 words
A method for forming a semiconductor device as defined in claim 10, wherein said second semiconductor film is formed in an amorphous state and annealed to a polycrystalline state by said irradiating of the laser beam.
References Cited (Backward Citations)
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