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US4498224A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of manufacturing a MOSFET using accelerated ions to form an amorphous region

Assignee: Toshiba Corp
•
Filing: 1982-10-24
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Granted: 1985-02-12
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Expires: 2002-10-24
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Abstract

Abstract A method for manufacturing MOSFET type semiconductor devices comprises forming a gate insulation layer and a gate electrode on a single crystal semiconductor substrate; introducing impurities in the substrate using the gate electrode as a mask; introducing accelerated ions deeper into the substrate than the impurities and overlapping at least a portion of the region in which the impurities are introduced in order to convert that portion to an amorphous state; diffusing the impurities into the amorphous region using a heating atmosphere, in order to form source and drain regions and, at the same time, converting the amorphous region to a single crystal; and forming source and drain electrodes in contact with the source and drain regions.

Inventors

  • 👤 Kenji Maeguchi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 03:42
CPC Classifications
H; H10; H10D; H10D30/00; H10D30/60; H10D30/67; H10D30/6704; H10D30/6713; H10D30/6715; H10P; H10P30/00; H10P30/20; H10P30/21; H10D62/00; H10D62/10; H10D62/13; H10D62/149; H10D62/151; H10P30/202; H10P30/204; H10P30/208; H10P30/28; H10P32/00; H10P32/10; H10P32/14; H10P32/1404; H10P32/1406; H10P32/17; H10P32/171; Y; Y10; Y10S; Y10S148/00; Y10S148/082

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 135 words
A method for manufacturing semiconductors of the MOSFET type comprising the steps of: forming a gate insulation layer and a gate electrode on a selected portion of a semiconductor body of single crystal material having a first conductivity type; introducing impurities of a second conductivity type into a preselected region of the semiconductor body using the gate electrode as a mask; introducing accelerated ions to overlap at least a portion of the region in which the impurities are introduced, wherein a fraction of the accelerated ions is introduced deeper than the impurities, said accelerated ion introducing step converting the crystal material of said semiconductive body portion into an amorphous state; forming a diffused region by diffusion of the second conductivity type impurities from said preselected region; and forming an electrode to contact the diffused region.
Claim 2
Independent Claim 135 words
A method for manufacturing semiconductors of the MOSFET type comprising the steps of: forming a gate insulation layer and a gate electrode on a selected portion of a semiconductor body of single crystal material having a first conductivity type; introducing impurities of a second conductivity type into a preselected region of the semiconductor body using the gate electrode as a mask; introducing accelerated ions to overlap at least a portion of the region in which the impurities are introduced, wherein a fraction of the accelerated ions is introduced deeper than the impurities, said accelerated ion introducing step converting the crystal material of said semiconductive body portion into an amorphous state; forming a diffused region by diffusion of the second conductivity type impurities from said preselected region; and forming an electrode to contact the diffused region.
Claim 3
Dependent Claim 14 words
The manufacturing method according to claim 1, wherein the accelerated ions are Si ions.
Claim 4
Dependent Claim 29 words
The manufacturing method according to claim 1, wherein the diffused region has a shallow portion and a deep portion, and the electrode is formed to contact the deep portion.
Claim 5
Dependent Claim 37 words
The manufacturing method according to claim 1, wherein the accelerated ions are introduced through a hole in an insulation layer formed to cover said preselected region, said insulation layer having been formed after said impurity introducing step.
Claim 6
Dependent Claim 15 words
The manufacturing method according to claim 4, wherein the electrode is formed in said hole.
Claim 7
Dependent Claim 38 words
The manufacturing method according to claim 4 further comprising the step of introducing additional impurities through the hole, said additional impurity introducing step being accomplished after said accelerated ion introducing step and before said diffused region forming step.
Claim 8
Dependent Claim 18 words
A manufacturing method according to claim 1, wherein the semiconductive body is previously formed on a sapphire substrate.
Claim 9
Dependent Claim 27 words
The manufacturing method according to claim 1, wherein said diffused region forming step is carried out by heating the body to not more than about 700° C.

References Cited (Backward Citations)

US4344222A Cited
US4404733A Cited
US4383869A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-02-12 1988-08-13 1989-02-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-02-12 1992-08-13 1993-02-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-02-12 1996-08-13 1997-02-12 $7700.00 Window Closed / Lapsed

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