Reverse optical mastering for data storage disks

  • US 6,890,704 B2
  • Filed: 12/05/2000
  • Issued: 05/10/2005
  • Est. Priority Date: 04/06/1998
  • Status: Expired due to Term
First Claim
Patent Images

1. A method of creating replica disks that define a desired replica pattern having flat coplanar land tops that define widths in a range of approximately 80-200 nanometers and groove depths in a range of approximately 20-120 nanometers comprising:

  • focusing light from a laser in a mastering system to form a focused laser spot on a photosensitive master, the focused law spot defining a laser spot size, wherein the laser spot size is defined by a full width at half maximum intensity;

    laser etching the photosensitive master to form a master pattern that is inverse of the desired replica pattern, the desired replica pattern defining a track pitch less than 2 multiplied by the laser spot size associated with the laser used to perform the laser etching, wherein the track pitch is less than approximately 700 nanometers, and wherein the laser etching defines master groove bottom widths of the master pattern, which correspond to flat coplanar land tops of the desired replica pattern, substantially independently of a master groove depth of the master pattern;

    creating a first generation stamper using the master, the first generation stamper having features that are inverted relative to the master such that the features of the first generation stamper correspond to the desired replica disk pattern;

    creating a second generation stamper using the first generation stamper, the second generation stamper having features that correspond to the master pattern; and

    creating replica disks using the second generation stamper, wherein the replica disks are formed with the desired replica pattern, which is inverted relative to the master pattern to define the flat coplanar land tops with widths in the range of 80-200 nanometers and the groove depths in the range of 20-120 nanometers.

View all claims

    Thank you for your feedback