International Business Machines Corporation

James S Wong

John C Cheng

Scott Arthur MacDonald

William D Hinsberg, Iii

Timothy Martin Reith

Lester A Pederson

Robert T Lynch, Jr

A method of manufacturing a photomask for the production of dual depth features on substrates, and the photomask so manufactured, wherein the method of manufacturing the photomask is comprised of the steps of: (1) coating a substrate which transmits at least two selected wavelengths with: a) an optical filter material which prevents the transmission of at least one of the wavelengths, b) an opaque masking material, and c) a dual tone photoresist; (2) using a single mastering tool to selectively expose areas of the coated substrate to one of the wavelengths; (3) developing the photoresist; (4) etching the exposed masking material and optical filter material; (5) exposing the remaining coated substrate; (6) developing the remaining photoresist; (7) etching the exposed surface; and (8) stripping away the remaining photoresist.

Dichromatic photomask and a method for its fabrication

An optical data storage device having a substrate has guide ridges, or reverse grooves, in a concentric or spiral shape formed thereon, and disposed in a plane parallel to and disposed from the substrate surface. The device further has pits formed approximately midway between the guide ridges and disposed in the substrate and having bottoms below the plane of the substrate surface. A method for manufacturing the optical data storage device having both address pits and guide ridges is disclosed. A dual tone photosensitive material is applied to a substrate, exposed with a laser light source comprising two distinct wavelengths, and developed to provide a desired bipolar geometry thereon.

Patterning process for bipolar optical storage medium

Growing community of inventors

San Jose, CA, United States of America

James S Wong