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US3725151A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of making an igfet defice with reduced gate-to- drain overlap capacitance

Assignee: Motorola Solutions Inc
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Filing: 1971-10-29
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Granted: 1973-04-03
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Expires: 1991-10-29
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Abstract

Abstract The disclosure teaches a method for producing an IGFET device characterized by an extremely narrow gate area with no overlapping of the source and drain regions. A controlled etch is used to form a pattern in a first layer over the substrate to precisely define the gate width. The substrate is subsequently oxidized so that the material covering the gate area can be preferentially etched away, thereby creating a window precisely defining the gate electrode. The need for precisely registering masks is avoided. A superior IGFET with greater speed of response and other concomitant advantages results.

Inventors

  • 👤 D Zoroglu

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 06:24
CPC Classifications
H; H10; H10W; H10W74/00; H10W74/40; H10D; H10D99/00; H10P; H10P95/00; Y; Y10; Y10S; Y10S148/00; Y10S148/043; Y10S148/051; Y10S148/053; Y10S148/106

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 28 words
The invention of claim 1 wherein the substrate is monocrystalline silicon(111) and the first and second layers of said sandwich are composed of silicon nitride and silica respectively.
Claim 2
Dependent Claim 22 words
The invention of claim 1 wherein the width of said gate area defined by said undercut first layer is approximately 0.25 micron.

References Cited (Backward Citations)

US3484313A Cited
US3479237A Cited
US3519504A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-04-02 1976-10-02 1977-04-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-04-02 1980-10-02 1981-04-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-04-02 1984-10-02 1985-04-03 $7700.00 Window Closed / Lapsed

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