Patent ID: 6994938
Filing Date: 2006-02-07
Classification: G03F,G03H

Abstract:
1. A method for producing a hologram mask approximating the exposure produced by a non-holographic phase shifting photomask comprising: exposing a hologram recording material to a first object light that is at least partially transmitted through a first original mask having a light transmitting screening pattern and a first reference light that is directed onto the hologram recording material wherein a first phase difference exists between the first object light and the first reference light; and exposing the hologram recording material to a second object light that is at least partially transmitted through a second original mask having a light transmitting screening pattern and a second reference light that is directed onto the hologram recording material wherein a second phase difference exists between the second object light and the second reference light, wherein the first phase difference and the second phase difference are not the same, and wherein the first and second original mask images recorded in the hologram recording material can be simultaneously replayed to produce an exposed pattern approximating an exposed pattern produced by a non-holographic phase shifting photomask.