Method of making reference surface markings on semiconductor wafers by laser beam

  • US 4,522,656 A
  • Filed: 04/26/1984
  • Issued: 06/11/1985
  • Est. Priority Date: 07/07/1983
  • Status: Expired due to Term
First Claim
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1. In a method for the characterization of semiconductor surfaces by means of surface patterns, which are each generated by melting and partial vaporization of a surface segment by means of a laser pulse, the improvement comprising the steps of:

  • irradiating by means of a laser pulse a surface segment of the semiconductor surface whose surface area corresponds to 1.5 to 6.5 times the surface area of the desired surface pattern; and

    adjusting the energy of the laser pulse so that melting and partial vaporization of the semiconductor material takes place only in the center of said surface segment on a surface of the semiconductor material corresponding to the desired surface pattern.

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