Method of stripping off wafer-protective sheet

• US 5,254,201 A
• Filed: 01/23/1992
• Issued: 10/19/1993
• Est. Priority Date: 08/30/1989
• Status: Expired due to Term

• Current Assignee: Nitto Denko Corporation
• Original Assignee: Nitto Denko Corporation
• Inventors: Kubozono, Tatuya, Yamamoto, Shoji, Kuwabara, Yutaka, Shigemura, Eiji, Konda, Yukari
• Primary Examiner(s): Simmons, David A.
• Assistant Examiner(s): Osele, Mark A.
• Application Number:
  US07/824,564
• Time in Patent Office: 635 Days
• Field of Search: 156/247, 156/344, 156/584
• US Class Current: 156/751
• CPC Class Codes: B29C 63/0013 Removing old coatings
• CPC Class Codes: H01L 21/67132 Apparatus for placing on an insulating substrate, e.g. tape
• CPC Class Codes: Y10T 156/19 Delaminating means
• CPC Class Codes: Y10T 156/1906 Delaminating means responsive to feed or shape at delamination

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.

Claims

1. 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.

2. 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.

3. 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 10¹² Ω

/□

or less.

4. 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.