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US5254201A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of stripping off wafer-protective sheet

Assignee: Nitto Denko Corp
•
Filing: 1992-01-23
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Granted: 1993-10-19
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Expires: 2012-01-23
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Abstract

Abstract A method of stripping off a wafer-protective sheet which comprises bonding an electrically conductive continuousform stripping tape comprising a flexible substrate to, through a pressure-sensitive adhesive layer, an electrically conductive protective sheet applied to a semiconductor wafer on its side where a circuit pattern has been formed, and then peeling the stripping tape from the semiconductor wafer thereby to strip the protective sheet from the semiconductor wafer, said bonding and peeling of the stripping tape being conducted automatically by means of an automatic stripping system while the protective sheet is kept being grounded through the stripping tape.

Inventors

  • 👤 Yukari Konda
  • 👤 Eiji Shigemura
  • 👤 Yutaka Kuwabara
  • 👤 Shoji Yamamoto
  • 👤 Tatuya Kubozono

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 10:59
CPC Classifications
H; H10; H10P; H10P72/00; H10P72/04; H10P72/0442; B; B29; B29C; B29C63/00; B29C63/0004; B29C63/0013; Y; Y10; Y10T; Y10T156/00; Y10T156/19; Y10T156/1906

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 94 words
A method of stripping off a wafer protective sheet comprising: (1) bonding with a pressure-sensitive adhesive layer (a) an electrically conductive protective sheet applied to a semiconductor wafer on its side where a circuit pattern has been formed, and (b) an electrically conductive continuous-form stripping tape comprising a flexible substrate and a conductive layer; and (2) peeling the stripping tape from the semiconductor wafer; wherein said bonding and peeling of the stripping tape is conducted automatically by means of an automatic stripping system while the protective sheet is kept grounded through the stripping tape.
Claim 2
Independent Claim 94 words
A method of stripping off a wafer protective sheet comprising: (1) bonding with a pressure-sensitive adhesive layer (a) an electrically conductive protective sheet applied to a semiconductor wafer on its side where a circuit pattern has been formed, and (b) an electrically conductive continuous-form stripping tape comprising a flexible substrate and a conductive layer; and (2) peeling the stripping tape from the semiconductor wafer; wherein said bonding and peeling of the stripping tape is conducted automatically by means of an automatic stripping system while the protective sheet is kept grounded through the stripping tape.
Claim 3
Independent Claim 107 words
A method of stripping off a wafer protective sheet comprising: (1) bonding with a pressure-sensitive adhesive layer (a) an electrically conductive protective sheet applied to a semiconductor wafer on its side where a circuit pattern has been formed, and (b) an electrically conductive continuous-form stripping tape comprising a flexible substrate and a conductive layer; and (2) peeling the stripping tape from the semiconductor wafer; wherein said bonding and peeling of the stripping tape is conducted automatically by means of an automatic stripping system while the protective sheet is kept grounded through the stripping tape and wherein the amount of static electricity generated is 500 V or less.
Claim 4
Independent Claim 107 words
A method of stripping off a wafer protective sheet comprising: (1) bonding with a pressure-sensitive adhesive layer (a) an electrically conductive protective sheet applied to a semiconductor wafer on its side where a circuit pattern has been formed, and (b) an electrically conductive continuous-form stripping tape comprising a flexible substrate and a conductive layer; and (2) peeling the stripping tape from the semiconductor wafer; wherein said bonding and peeling of the stripping tape is conducted automatically by means of an automatic stripping system while the protective sheet is kept grounded through the stripping tape and wherein the amount of static electricity generated is 500 V or less.
Claim 5
Independent Claim 114 words
A method of stripping off a wafer protective sheet comprising: (1) bonding with a pressure-sensitive adhesive layer (a) an electrically conductive protective sheet applied to a semiconductor wafer on its side where a circuit pattern has been formed and (b) an electrically conductive continuous-form stripping tape comprising a flexible substrate and a conductive layer; and (2) peeling the stripping tape from the semiconductor wafer; wherein said bonding and peeling of the stripping tape is conducted automatically by means of an automatic stripping system while the protective sheet is kept grounded through the stripping tape and wherein both the stripping tape and the protective sheet have a surface resistivity of 10 12 Ω/□ or less.
Claim 6
Independent Claim 114 words
A method of stripping off a wafer protective sheet comprising: (1) bonding with a pressure-sensitive adhesive layer (a) an electrically conductive protective sheet applied to a semiconductor wafer on its side where a circuit pattern has been formed and (b) an electrically conductive continuous-form stripping tape comprising a flexible substrate and a conductive layer; and (2) peeling the stripping tape from the semiconductor wafer; wherein said bonding and peeling of the stripping tape is conducted automatically by means of an automatic stripping system while the protective sheet is kept grounded through the stripping tape and wherein both the stripping tape and the protective sheet have a surface resistivity of 10 12 Ω/□ or less.
Claim 7
Independent Claim 116 words
A method of stripping off a wafer protective sheet comprising: (1) bonding with a pressure-sensitive adhesive layer (a) an electrically conductive protective sheet applied to a semiconductor wafer on its side where a circuit pattern has been formed, and (b) an electrically conductive continuous-form stripping tape comprising a flexible substrate and a conductive layer; and (2) peeling the stripping tape from the semiconductor wafer; wherein said bonding and peeling of the stripping tape is conducted automatically by means of an automatic stripping system while the protective sheet is kept grounded through the stripping tape and wherein said pressure-sensitive adhesive layer has greater adhesive strength than the adhesive strength between said protective sheet and said semiconductor wafer.
Claim 8
Independent Claim 116 words
A method of stripping off a wafer protective sheet comprising: (1) bonding with a pressure-sensitive adhesive layer (a) an electrically conductive protective sheet applied to a semiconductor wafer on its side where a circuit pattern has been formed, and (b) an electrically conductive continuous-form stripping tape comprising a flexible substrate and a conductive layer; and (2) peeling the stripping tape from the semiconductor wafer; wherein said bonding and peeling of the stripping tape is conducted automatically by means of an automatic stripping system while the protective sheet is kept grounded through the stripping tape and wherein said pressure-sensitive adhesive layer has greater adhesive strength than the adhesive strength between said protective sheet and said semiconductor wafer.

References Cited (Backward Citations)

US4111724A Cited
US4285759A Cited
US4775438A Cited
US4631103A Cited
US5009735A Cited
US4861411A Cited
JPH0385745A Cited
US5006190A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-10-18 1997-04-19 1997-10-19 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-10-18 2001-04-19 2001-10-19 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-10-18 2005-04-19 2005-10-19 $7700.00 Window Closed / Lapsed

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