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US5883399A Expired / Lapsed US ⏱️ 0.0 years remaining

Thin film transistor having double channels and its manufacturing method

Assignee: SK Hynix Inc
•
Filing: 1997-07-08
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Granted: 1999-03-16
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Expires: 2017-07-08
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Abstract

Abstract This invention provides a method for manufacturing a this film transistor which comprised the steps of providing an oxide layer; etching a portion of the oxide layer so that a recess is formed; forming a first channel layer on the resulting structure; forming a first gate oxide layer on the first channel layer in a portion including the recess region; forming a polysilicon layer on the resulting structure, filling in the recess region; etching back the polysilicon layer until the surface of a portion of the first gate oxide layer, leaving the residual layer on the first channel layer, which is exposed by the first gate oxide layer, wherein the surface of the resulting structure has uniform topology by the etching process; forming a second gate oxide layer on the polysilicon layer; forming a second channel layer on the resulting structure; and implanting impurity ions for forming source/drain regions, whereby the source/drain region consists of multi-layers, the first channel layer, the second polysilicon layer and the second channel layer.

Inventors

  • 👤 Sung Wook Yin
  • 👤 Yun Ki Kim

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 23:59
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/01; H10D30/021; H10D30/031; H10D30/0321; H10D30/60; H10D30/67; H10D30/674; H10D30/6757; H10D30/0312

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 133 words
A thin film transistor having double channels, comprising: an insulating layer; a first channel layer formed on said insulating layer; a first gate insulating layer partially formed on said first channel layer; a gate electrode partially formed on said first gate insulating layer; a second gate insulating layer formed on said gate electrode; a polysilicon layer partially formed on each end of the first channel layer; and a second channel layer formed on said second gate insulating layer and the polysilicon layer, wherein said second channel layer is electrically connected with said first channel layer through the polysilicon layer such that each end of the channel layers consisted of the first channel layer, the polysilicon layer and the second channel layer is thicker than the channel layers so that the on-current is increased.
Claim 2
Dependent Claim 133 words
A thin film transistor having double channels, comprising: an insulating layer; a first channel layer formed on said insulating layer; a first gate insulating layer partially formed on said first channel layer; a gate electrode partially formed on said first gate insulating layer; a second gate insulating layer formed on said gate electrode; a polysilicon layer partially formed on each end of the first channel layer; and a second channel layer formed on said second gate insulating layer and the polysilicon layer, wherein said second channel layer is electrically connected with said first channel layer through the polysilicon layer such that each end of the channel layers consisted of the first channel layer, the polysilicon layer and the second channel layer is thicker than the channel layers so that the on-current is increased.
Claim 3
Dependent Claim 15 words
A thin film transistor according to claim 1, wherein said insulating layer has a recess.
Claim 4
Dependent Claim 17 words
A thin film transistor according to claim 2, wherein said gate electrode is formed in the recess.
Claim 5
Dependent Claim 18 words
A thin film transistor according to claim 2, wherein said gate electrode is polysilicon which fills the recess.
Claim 6
Dependent Claim 22 words
A thin film transistor according to claim 1, wherein said first and second channels constitute a first and second current paths, respectively.
Claim 7
Dependent Claim 21 words
A thin film transistor according to claim 5, wherein the first current path is formed beneath said first gate insulating layer.
Claim 8
Dependent Claim 21 words
A thin film transistor according to claim 5, wherein the second current path is formed above said second gate insulating layer.
Claim 9
Dependent Claim 19 words
A thin film transistor according to claim 1, wherein said first and second gate insulating layers are oxide layers.
Claim 10
Dependent Claim 40 words
A thin film transistor according to claim 1, wherein one end of said first and second channel layers forms a drain region and the other end of said first and second channel layers forms a source region of said transistor.
Claim 11
Dependent Claim 35 words
A thin film transistor according to claim 9, wherein an upper surface of a resulting structure comprised of said source and drain regions, said gate electrode and said first gate insulating layer has uniform topology.
Claim 12
Dependent Claim 18 words
A thin film transistor according to claim 1, wherein said first and second channel layers are polysilicon layers.
Claim 13
Dependent Claim 119 words
A thin film transistor comprising: an insulating layer having a recess; and a transistor formed on said insulating layer, said transistor having first and second current paths, wherein a gate electrode of said transistor is formed in said recess, said transistor comprising: a first channel layer formed on said insulating layer; a first gate insulating layer formed on said first channel layer such that said first channel layer forms said first current path beneath said first gate insulating layer; a second gate insulating layer formed on said gate electrode; and a second channel layer formed on said second gate insulating layer such that said second gate insulating layer forms said second current path above said second gate insulating layer.
Claim 14
Dependent Claim 119 words
A thin film transistor comprising: an insulating layer having a recess; and a transistor formed on said insulating layer, said transistor having first and second current paths, wherein a gate electrode of said transistor is formed in said recess, said transistor comprising: a first channel layer formed on said insulating layer; a first gate insulating layer formed on said first channel layer such that said first channel layer forms said first current path beneath said first gate insulating layer; a second gate insulating layer formed on said gate electrode; and a second channel layer formed on said second gate insulating layer such that said second gate insulating layer forms said second current path above said second gate insulating layer.
Claim 15
Dependent Claim 18 words
A thin film transistor according to claim 12, wherein said first and second channel layers are polysilicon layers.
Claim 16
Dependent Claim 35 words
A thin film transistor according to claim 12, wherein an upper surface of a resulting structure comprised of said source and drain regions, said gate electrode and said first gate insulating layer has uniform topology.
Claim 17
Dependent Claim 19 words
A thin film transistor according to claim 12, wherein said first and second gate insulating layers are oxide layers.
Claim 18
Dependent Claim 40 words
A thin film transistor according to claim 12, wherein one end of said first and second channel layers forms a drain region and the other end of said first and second channel layers forms a source region of said transistor.

References Cited (Backward Citations)

US5082795A Cited
US4951102A Cited
US5298782A Cited
US5221849A Cited
US5372959A Cited
US5348899A Cited
US5362669A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2002-03-15 2002-09-14 2003-03-16 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2006-03-15 2006-09-14 2007-03-16 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2010-03-15 2010-09-14 2011-03-16 $7700.00 Window Closed / Lapsed

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