Patent ID: 9164373
Filing Date: 2015-10-20
Classification: G03F

Abstract:
1. A method for writing a pattern according to an input pattern specification with repeated features on a large area photomask or a camera detector photomask with suppressed mura errors, comprising: providing a stage and a writing head with x-y relative movements, the x relative movements being essentially perpendicular to the y relative movements, said writing head having a primary axis and a secondary axis essentially aligned with the x-y relative movements, loading a photomask substrate at a first rotation angle larger than 5 degrees to the x-y relative movements and exposing a first pattern in a first pass, physically rotating the photomask substrate to a second rotation angle at least 10 degrees from the first rotation angle and exposing a second pattern in a second pass, wherein the first and second patterns are based on the same input pattern specification and are aligned in the first and second passes.