US5807772A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for forming semiconductor device with bottom gate connected to source or drain
Assignee: Semiconductor Energy Laboratory Co Ltd
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Filing: 1995-06-05
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Granted: 1998-09-15
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Expires: 2015-06-05
Abstract
Abstract In a field effect type device having a thin film-like active layer, there is provided a thin film-like semiconductor device including a top side gate electrode on the active layer and a bottom side gate electrode connected to a static potential, the bottom side gate electrode being provided between the active layer and a substrate. The bottom side gate electrode may be electrically connected to only one of a source and a drain of the field effect type device. Also, the production methods therefor are disclosed.
Inventors
- 👤 Yasuhiko Takemura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 22:18
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/01; H10D30/021; H10D30/031; H10D30/0312; H10D30/0314; H10D30/0321; H10D30/60; H10D30/67; H10D30/6729; H10D30/673; H10D30/6733; H10D30/6734; H10D86/00; H10D86/40; H10D86/471; H10D86/60
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
131 words
A method of forming a semiconductor device comprising: forming a conductive gate electrode on an insulating surface; forming a first insulating film on said gate electrode; forming a semiconductor film comprising source, drain and channel regions on said first insulating film; forming a second insulating film on said semiconductor film; forming a mask for etching on said second insulating film; isotropically etching said second insulating film through an opening in said mask to form a contact hole in said second insulating film; anisotropically etching said semiconductor film with said mask to form an opening in said semiconductor film; etching said first insulating film with said mask to form an opening in said first insulating film; and selectively forming a conductive electrode to electrically connect the gate electrode with the semiconductor film.
Claim 2
Independent Claim
131 words
A method of forming a semiconductor device comprising: forming a conductive gate electrode on an insulating surface; forming a first insulating film on said gate electrode; forming a semiconductor film comprising source, drain and channel regions on said first insulating film; forming a second insulating film on said semiconductor film; forming a mask for etching on said second insulating film; isotropically etching said second insulating film through an opening in said mask to form a contact hole in said second insulating film; anisotropically etching said semiconductor film with said mask to form an opening in said semiconductor film; etching said first insulating film with said mask to form an opening in said first insulating film; and selectively forming a conductive electrode to electrically connect the gate electrode with the semiconductor film.
Claim 3
Dependent Claim
17 words
The method of claim 1 wherein said anisotropically etching step is carried out by reactive ion etching.
Claim 4
Dependent Claim
26 words
The method of claim 1 wherein said contact hole is wider than said opening of said mask by virtue of isotropy of said isotropically etching step.
Claim 5
Dependent Claim
46 words
The method of claim 1 wherein said contact hole formed in said second insulating film has a larger diameter than the opening opened in said semiconductor film so that said conductive electrode electrically contacts with an upper surface of said semiconductor film in said contact hole.
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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) | 2001-09-14 | 2002-03-16 | 2002-09-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-09-14 | 2006-03-16 | 2006-09-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-09-14 | 2010-03-16 | 2010-09-15 | $7700.00 | Window Closed / Lapsed |