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Junction field effect transistor

Assignee: Nippon Gakki Co Ltd
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Filing: 1979-08-06
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Granted: 1981-09-08
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Expires: 1999-08-06
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Abstract

Abstract A vertical or horizontal type junction FET including a channel-gate structure formed by a double diffusion process in which two treatments for diffusing different impurities are executed through an identical opening provided in a diffusion mask. For fabricating a vertical type junction FET, such double diffusion process is applied to stacked upper and lower semi-conductor layers having opposite conducting types thereby forming a channel region adjacent to the upper semi-conductor layer which functions as a first gate region and forming a second gate region adjacent to the channel region and remote from the first gate region. For fabricating horizontal type junction FET, the double diffusion process stated above is applied to a single semi-conductor layer to form a first gate region thereby forming a channel region adjacent to the first gate region and a second gate region adjacent to the channel region and remote from the first gate region. In either type of junction FET's the width of each channel region is precisely determined and corresponds to the difference in the diffusion depths in the two diffusion treatments. Moreover, the impurity concentration and the concentration profile of each channel region is determined independently of those of the drain or source region. Furthermore in the manufacturing process of each FET, the second gate region is self aligned so as to overlap a corresponding channel region.

Inventors

  • 👤 Takashi Yoshida
  • 👤 Takeshi Matsuyama
  • 👤 Tamaki Kuki
  • 👤 Takayuki Kodaka

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 08:45
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/01; H10D30/051; H10D30/0512; H10D30/0515; H10D30/80; H10D30/83; H10D30/831; Y; Y10; Y10S; Y10S148/00; Y10S148/126

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 179 words
A junction field transistor comprising: a semiconductor substrate having one principal surface, said substrate including a first semiconductor layer of one conductivity type extending substantially in parallel with said principal surface and a second semiconductor layer of the opposite conductivity type to said one conductivity type formed on said first semiconductor layer and extending substantially in parallel with said principal surface; a first diffused region of said one conductivity type formed in said second semiconductor layer in accordance with a predetermined channel pattern and reaching said first semiconductor layer; a second diffused region of said opposite conductivity type formed in said first diffused region to define a channel region of said one conductivity type between said second diffused region and said second semiconductor layer, one end of said channel region being conductively coupled with said first semiconductor layer; a first main electrode electrically connected to said first semiconductor layer; a control electrode electrically connected to said second diffused region; and a second main electrode electrically connected to the other end of said channel region on said second semiconductor layer.
Claim 2
Dependent Claim 179 words
A junction field transistor comprising: a semiconductor substrate having one principal surface, said substrate including a first semiconductor layer of one conductivity type extending substantially in parallel with said principal surface and a second semiconductor layer of the opposite conductivity type to said one conductivity type formed on said first semiconductor layer and extending substantially in parallel with said principal surface; a first diffused region of said one conductivity type formed in said second semiconductor layer in accordance with a predetermined channel pattern and reaching said first semiconductor layer; a second diffused region of said opposite conductivity type formed in said first diffused region to define a channel region of said one conductivity type between said second diffused region and said second semiconductor layer, one end of said channel region being conductively coupled with said first semiconductor layer; a first main electrode electrically connected to said first semiconductor layer; a control electrode electrically connected to said second diffused region; and a second main electrode electrically connected to the other end of said channel region on said second semiconductor layer.
Claim 3
Dependent Claim 23 words
A junction field effect transistor according to claim 1, further comprising means for electrically connecting said second semiconductor layer to said control electrode.
Claim 4
Dependent Claim 20 words
A junction field effect transistor according to claim 1, further comprising another control electrode electrically connected to said second semiconductor.
Claim 5
Dependent Claim 216 words
A junction field effect transistor comprising: a semiconductor substrate having one principal surface, said substrate including a first semiconductor layer of one conductivity type extending substantially in parallel with said principal surface, a second semiconductor layer of the opposite conductivity type to said one conductivity type formed on said first semiconductor layer and extending substantially in parallel with said principal surface and a third semiconductor layer of said one conductivity type formed on said second semiconductor layer and extending substantially in parallel with said principal surface; a first diffused region of said one conductivity type formed in said third semiconductor layer in accordance with a predetermined channel pattern and reaching said first semiconductor layer through said second semiconductor layer; a second diffused region of said opposite conductivity type formed in said first diffused region to define a channel region of said one conductivity type between said second diffused region and said second semiconductor layer, one end of said channel region being conductively coupled with said first semiconductor layer, the other end of said channel region being conductively coupled with said third semiconductor layer; a first main electrode electrically connected to said first semiconductor layer; a control electrode electrically connected to said second diffused region; and a second main electrode electrically connected to said third semiconductor layer.
Claim 6
Dependent Claim 216 words
A junction field effect transistor comprising: a semiconductor substrate having one principal surface, said substrate including a first semiconductor layer of one conductivity type extending substantially in parallel with said principal surface, a second semiconductor layer of the opposite conductivity type to said one conductivity type formed on said first semiconductor layer and extending substantially in parallel with said principal surface and a third semiconductor layer of said one conductivity type formed on said second semiconductor layer and extending substantially in parallel with said principal surface; a first diffused region of said one conductivity type formed in said third semiconductor layer in accordance with a predetermined channel pattern and reaching said first semiconductor layer through said second semiconductor layer; a second diffused region of said opposite conductivity type formed in said first diffused region to define a channel region of said one conductivity type between said second diffused region and said second semiconductor layer, one end of said channel region being conductively coupled with said first semiconductor layer, the other end of said channel region being conductively coupled with said third semiconductor layer; a first main electrode electrically connected to said first semiconductor layer; a control electrode electrically connected to said second diffused region; and a second main electrode electrically connected to said third semiconductor layer.
Claim 7
Dependent Claim 42 words
A junction field effect transistor according to claim 4, further comprising a third diffused region of said opposite conductivity type formed in said third semiconductor layer to be integral with said second diffused region and extending substantially into said second semiconductor layer.
Claim 8
Dependent Claim 45 words
A junction field effect transistor according to claim 4, further comprising a third diffused region of said opposite conductivity type formed in said third semiconductor layer and extending substantially into said second semiconductor layer, and another control electrode electrically connected to said third diffused region.
Claim 9
Dependent Claim 196 words
A junction field effect transistor comprising: a semiconductor substrate having one principal surface, said substrate including a first semiconductor layer of one conductivity type extending substantially in parallel with said principal surface and a second semiconductor layer of the opposite conductivity type to said one conductivity type formed on said first semiconductor layer and extending substantially in parallel with said principal surface; a first diffused region of said opposite conductivity type formed in said second semiconductor layer in accordance with a predetermined channel pattern and extending substantially into said first semiconductor layer; a second diffused region of said one conductivity type formed in said first diffused region to define a channel region of said opposite conductivity type between said second diffused region and said first semiconductor layer, said second difused region dividing said second semiconductor layer into first and second portions with which one and the other ends of said channel region are conductively coupled respectively; a first main electrode electrically connected to said first portion of said second semiconductor layer; a second main electrode electrically connected to said second portion of said second semiconductor; and a control electrode electrically connected to said second diffused region.
Claim 10
Dependent Claim 196 words
A junction field effect transistor comprising: a semiconductor substrate having one principal surface, said substrate including a first semiconductor layer of one conductivity type extending substantially in parallel with said principal surface and a second semiconductor layer of the opposite conductivity type to said one conductivity type formed on said first semiconductor layer and extending substantially in parallel with said principal surface; a first diffused region of said opposite conductivity type formed in said second semiconductor layer in accordance with a predetermined channel pattern and extending substantially into said first semiconductor layer; a second diffused region of said one conductivity type formed in said first diffused region to define a channel region of said opposite conductivity type between said second diffused region and said first semiconductor layer, said second difused region dividing said second semiconductor layer into first and second portions with which one and the other ends of said channel region are conductively coupled respectively; a first main electrode electrically connected to said first portion of said second semiconductor layer; a second main electrode electrically connected to said second portion of said second semiconductor; and a control electrode electrically connected to said second diffused region.
Claim 11
Dependent Claim 45 words
A junction field effect transistor according to claim 7, further comprising a third diffused region of said one conductivity type formed in said second semiconductor layer and extending substantially into said first semiconductor layer, and another control electrode electrically connected to said third diffused region.
Claim 12
Dependent Claim 182 words
A junction field effect transistor comprising: a semiconductor substrate having one principal surface, said substrate including a first semiconductor layer of one conductivity type extending substantially in parallel with said principal surface and a second semiconductor layer of the opposite conductivity type to said one conductivity type formed on said first semiconductor layer and extending substantially in parallel with said principal surface; a first diffused region of said one conductivity type formed in said second semiconductor layer in accordance with a predetermined channel pattern and reaching said first semiconductor layer, said first diffused region having in a surface thereof a recess formed in accordance with said predetermined channel pattern to define a channel region of said one conductivity type between said recess and said second semiconductor layer, one end of said channel region being conductively coupled with said first semiconductor layer; a first main electrode electrically connected to said first semiconductor layer; a control electrode electrically connected to said second semiconductor layer; and a second main electrode electrically connected to the other end of said channel region on said second semiconductor layer.
Claim 13
Dependent Claim 182 words
A junction field effect transistor comprising: a semiconductor substrate having one principal surface, said substrate including a first semiconductor layer of one conductivity type extending substantially in parallel with said principal surface and a second semiconductor layer of the opposite conductivity type to said one conductivity type formed on said first semiconductor layer and extending substantially in parallel with said principal surface; a first diffused region of said one conductivity type formed in said second semiconductor layer in accordance with a predetermined channel pattern and reaching said first semiconductor layer, said first diffused region having in a surface thereof a recess formed in accordance with said predetermined channel pattern to define a channel region of said one conductivity type between said recess and said second semiconductor layer, one end of said channel region being conductively coupled with said first semiconductor layer; a first main electrode electrically connected to said first semiconductor layer; a control electrode electrically connected to said second semiconductor layer; and a second main electrode electrically connected to the other end of said channel region on said second semiconductor layer.
Claim 14
Dependent Claim 46 words
A junction field effect transistor according to claim 9, further comprising a second diffused region formed in said first diffused region along a surface of said recess to make said channel region narrow, and means for electrically connecting said second diffused region to said control electrode.

References Cited (Backward Citations)

US3465216A Cited
US3982264A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-09-07 1985-03-09 1985-09-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-09-07 1989-03-09 1989-09-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-09-07 1993-03-09 1993-09-08 $7700.00 Window Closed / Lapsed

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