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US4980308A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of making a thin film transistor

Assignee: Sony Corp
•
Filing: 1989-11-13
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Granted: 1990-12-25
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Expires: 2009-11-13
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Abstract

Abstract The present invention relates to a semiconductor device in which a semiconductor element is formed on a semiconductor layer (3) supported on a substrate (1) via at least insulating layers (2) and (4) as shown in FIGS. 1 and 2 and a method of fabricating the same. The semiconductor layer (3) has wiring layers (5) and (6) on both surfaces thereof, thus leading itself well for increasing the density of wiring and for increasing the operation speed in a large-scale integrated circuit device.

Inventors

  • 👤 Hisao Hayashi
  • 👤 Takeshi Matsushita

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 08:41
CPC Classifications
H; H10; H10D; H10D84/00; H10D84/01; H10D84/0123; H10D84/0126; H10D84/0165; H10D84/0186; H10W; H10W20/00; H10W20/01; H10D84/017; H10W20/40; H10W20/41; H10W20/435; Y; Y10; Y10S; Y10S438/00; Y10S438/928; Y10S438/977

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 158 words
In a method of fabricating a semiconductor device consisting of a thin film semiconductor formed on an insulating substrate, comprising the steps of forming on a first major surface of a semiconductor substrate, a first insulating film, forming a first wiring layer which does not adjoin said semiconductor substrate on said insulating film, forming said insulating substrate on said first wiring layer, removing said semiconductor substrate from its second major surface side to form said thin film semiconductor layer, forming a second insulating film on said thin film semiconductor layer, forming a second thin semiconductor layer on said second insulting film, forming a gate film on said second thin semiconductor layer, forming a second gate on said gate film, using said second gate as a mask for ion implantation to form p and n source and drain regions, forming an insulating layer over said source and drain regions, and forming electrodes connected to said source and drain regions.
Claim 2
Dependent Claim 158 words
In a method of fabricating a semiconductor device consisting of a thin film semiconductor formed on an insulating substrate, comprising the steps of forming on a first major surface of a semiconductor substrate, a first insulating film, forming a first wiring layer which does not adjoin said semiconductor substrate on said insulating film, forming said insulating substrate on said first wiring layer, removing said semiconductor substrate from its second major surface side to form said thin film semiconductor layer, forming a second insulating film on said thin film semiconductor layer, forming a second thin semiconductor layer on said second insulting film, forming a gate film on said second thin semiconductor layer, forming a second gate on said gate film, using said second gate as a mask for ion implantation to form p and n source and drain regions, forming an insulating layer over said source and drain regions, and forming electrodes connected to said source and drain regions.

References Cited (Backward Citations)

US4139401A Cited
US3624463A Cited
US4131909A Cited
DE2752344A1 Cited
JPS5688354A Cited
US4468857A Cited
US4784970A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-12-24 1994-06-25 1994-12-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-12-24 1998-06-25 1998-12-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-12-24 2002-06-25 2002-12-25 $7700.00 Window Closed / Lapsed

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