US4968638A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Semiconductor devices
Assignee: BTG International Ltd
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Filing: 1988-09-02
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Granted: 1990-11-06
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Expires: 2008-09-02
Abstract
Abstract A method of manufacture of thin film, field-effect transistors formed on a transparent substrate and with transparent, conductive source and drain electrodes, uses initially deposited gate electrodes as a mask in association with photolithographic processing using radiation transmitted through the substrate and electrodes to minimize parasitic capacitance between the gate and source and drain electrodes.
Inventors
- 👤 Stephen W. Wright
- 👤 Charles P. Judge
- 👤 Michael J. Lee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:13
CPC Classifications
H; H10; H10D; H10D99/00; H10D30/00; H10D30/60; H10D30/67; H10D30/6729; H10D30/673; H10D30/6733; H10D30/6734; H10D30/674; H10D30/675; Y; Y10; Y10S; Y10S148/00; Y10S148/106
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
171 words
A method of manufacture of semiconductor devices comprising the steps of depositing on the surface of a transparent insulating substrate a first layer of conductive material adapted to form a first plurality of gate electrodes, depositing over said first layer of conductive material, a first layer of transparent insulating material, forming on the exposed surface of said first layer of insulating material a plurality of pairs of conductive contacts having gaps therebetween defined by photolithography involving exposure to radiation through said transparent insulation substrate using said first plurality of gate electrodes as a mask, depositing a layer of semiconductive material to form a semiconductive path between said pairs of conductive contacts, further depositing over said layer of semiconductive material and said conductive contacts a second layer of transparent insulating material, and depositing on said second layer of transparent insulating material a second plurality of gate electrodes having an area defined by photolithography involving exposure to radiation through said transparent insulation substrate using said first plurality of gate electrodes as a mask.
Claim 2
Independent Claim
171 words
A method of manufacture of semiconductor devices comprising the steps of depositing on the surface of a transparent insulating substrate a first layer of conductive material adapted to form a first plurality of gate electrodes, depositing over said first layer of conductive material, a first layer of transparent insulating material, forming on the exposed surface of said first layer of insulating material a plurality of pairs of conductive contacts having gaps therebetween defined by photolithography involving exposure to radiation through said transparent insulation substrate using said first plurality of gate electrodes as a mask, depositing a layer of semiconductive material to form a semiconductive path between said pairs of conductive contacts, further depositing over said layer of semiconductive material and said conductive contacts a second layer of transparent insulating material, and depositing on said second layer of transparent insulating material a second plurality of gate electrodes having an area defined by photolithography involving exposure to radiation through said transparent insulation substrate using said first plurality of gate electrodes as a mask.
Claim 3
Dependent Claim
29 words
A method of manufacture of semiconductor devices according to claim 1 including the further step of heat-treating the substrate to render the material of said pairs of electrodes conductive.
References Cited (Backward Citations)
EP0071244A2
Cited
EP0090661A2
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-11-05 | 1994-05-07 | 1994-11-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-11-05 | 1998-05-07 | 1998-11-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-11-05 | 2002-05-07 | 2002-11-06 | $7700.00 | Window Closed / Lapsed |