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US4979006A Expired / Lapsed US ⏱️ 0.0 years remaining

Reverse staggered type silicon thin film transistor

Assignee: Seiko Precision Inc
•
Filing: 1989-05-26
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Granted: 1990-12-18
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Expires: 2009-05-26
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Abstract

Abstract A reverse staggered type silicon thin film transistor includes a substrate having a gate electrode; a gate insulating layer on the substrate and the gate electrode, the gate insulating layer having a transistor-forming portion; a lower layer silicon film on the transistor-forming portion of the gate insulating layer and in contact therewith, the lower layer silicon film being formed at a first temperature and with a first thickness; an upper layer silicon film formed on the transistor-forming portion of the gate insulating layer at a second temperature which is lower than the first temperature and with a second thickness greater than the first thickness; and n-type silicon layer on the upper layer silicon film and in contact therewith; a source electrode on the n-type silicon layer; and a drain electrode on the n-type silicon layer.

Inventors

  • 👤 Sakae Tanaka
  • 👤 Yoshiaki Watanabe
  • 👤 Katsuo Shirai
  • 👤 Yoshihisa Ogiwara

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 14:16
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/60; H10D30/67; H10D30/6729; H10D30/673; H10D30/6732; H10D30/674; H10D30/6741; H10D30/6743; H10D30/6746

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 145 words
A reverse staggered type silicon thin film transistor, comprising: a gate electrode on a substrate; a gate insulating layer on said substrate and said gate electrode, said gate insulating layer having a transistor-forming portion; a lower layer silicon film on the transistor-forming portion of the gate insulating layer and in contact therewith, said lower layer silicon film being formed at a first temperature; an upper layer silicon film formed on said lower layer silicon film at a second temperature which is lower than said first temperature, said lower layer silicon film having a first thickness of approximately 30 nm and said upper layer silicon film having a second greater thickness of approximately 120 nm; an n-type silicon layer on said upper layer silicon film and in contact therewith; a source electrode on said n-type silicon layer; and a drain electrode on said n-type silicon layer.
Claim 2
Dependent Claim 145 words
A reverse staggered type silicon thin film transistor, comprising: a gate electrode on a substrate; a gate insulating layer on said substrate and said gate electrode, said gate insulating layer having a transistor-forming portion; a lower layer silicon film on the transistor-forming portion of the gate insulating layer and in contact therewith, said lower layer silicon film being formed at a first temperature; an upper layer silicon film formed on said lower layer silicon film at a second temperature which is lower than said first temperature, said lower layer silicon film having a first thickness of approximately 30 nm and said upper layer silicon film having a second greater thickness of approximately 120 nm; an n-type silicon layer on said upper layer silicon film and in contact therewith; a source electrode on said n-type silicon layer; and a drain electrode on said n-type silicon layer.

References Cited (Backward Citations)

JPS6066864A Cited
JPS60117781A Cited
JPS6159873A Cited
JPS6167964A Cited
US4746961A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-12-17 1994-06-18 1994-12-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-12-17 1998-06-18 1998-12-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-12-17 2002-06-18 2002-12-18 $7700.00 Window Closed / Lapsed

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