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US3761328A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of manufacturing semiconductor devices

Assignee: Toshiba Corp
•
Filing: 1970-06-23
•
Granted: 1973-09-25
•
Expires: 1990-06-23
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Abstract

Abstract AN INSULATING FILM MAINLY COMPOSED OF SILICON DIOXIDE AND HAVING AT LEAST ONE OPENING IS FORMED ON THE SURFACE OF A SEMICONDUCTOR WAFER AND THEN A READILY ECTHABLE FILM IS APPLIED ON THE EXPOSED SURFACE OF THE OPENING, WHICH IS MAINLY COMPOSED OF SILICON DIOXIDE AND CONTAINS AN IMPURITY ELEMENT ADAPTED TO FORM A SHALLOW IMPURITY LEVEL AND AN ADDITIVE SUBSTANCE WHICH INCREASES THE ETCHING SPEED OF THE READILY ETCHABLE FILM AFTER DIFFUSED WITH THE IMPURITY TO A VALUE HIGHER THAN THAT OF THE INSULATING FILM AND WHICH DOES NOT IMPAIR THE ELECTRICAL CHARACTERISTICS OF THE DIFFUSED AREA.

Inventors

  • 👤 T Abe
  • 👤 M Konaka
  • 👤 T Narita

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 09:36
CPC Classifications
H; H10; H10P; H10P95/00; H10D; H10D99/00; H10P14/00; H10P14/60; H10P14/63; H10P14/6326; H10P14/6328; H10P14/6329; H10P14/6334; H10P14/66; H10P14/662; H10P14/668; H10P14/6681; H10P14/6682; H10P14/69; H10P14/692; H10P14/6921; H10P14/69215; H10P14/6922; H10P14/6923; Y; Y10; Y10S; Y10S148/00; Y10S148/04; Y10S148/043; Y10S148/106; Y10S148/118; Y10S148/141; Y10S148/145; Y10S148/147; Y10S148/151

Claims Analysis

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References Cited (Backward Citations)

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-09-24 1977-03-26 1977-09-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-09-24 1981-03-26 1981-09-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-09-24 1985-03-26 1985-09-25 $7700.00 Window Closed / Lapsed

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