Mechanically produced alignment fiducial method and device

摘要

The technology disclosed relates to methods and systems that can be used to reduce visible artifacts know as mura. In particular, it relates to producing alignment marks by physically modifying appearance of a layer of exposure or radiation sensitive material on a workpiece, then using those alignment marks or transferred direct or inverted images of those marks to realign a writing coordinate system between exposure writing passes, following physical movement of the workpiece within the writing system. The physical modifications described include mechanically pressing a mark into the layer, using a laser to ash or ablate the layer, or applying an ink or other substance to the surface of the laser.

主权项

1. A method of aligning a workpiece between two exposure patterning operations, the method including:
forming fiducials by mechanical indentation using a point and a ram in an exposure sensitive layer on a workpiece to expose a first patterning layer underlying the exposure sensitive layer on the workpiece; measuring and recording first position information of the fiducials relative to a pattern of a first exposure in a first coordinate system, wherein the first coordinate system is used by a writing system to apply the first exposure to the workpiece; physically moving the workpiece and repositioning it in the writing system; measuring and recording second position information of the fiducials or of a transfer from the fiducials onto another layer of the workpiece; using the second position information to align a second coordinate system relative to the first coordinate system; and applying a second exposure to the workpiece using the second coordinate system.