Methods of imprint patterning of irregular surface

摘要

Patterned substrates for photovoltaic and other uses are made by pressing a flexible stamp upon a thin layer of resist material, which covers a substrate, such as a wafer. The resist changes phase or becomes flowable, flowing away from locations of impression, revealing the substrate, which is subjected to some shaping process. A typical substrate is silicon, and a typical resist is a wax. Workpiece textures include extended grooves, discrete, spaced apart pits, and combinations and intermediates thereof. Platen or rotary patterning apparatus may be used. Rough and irregular workpiece substrates may be accommodated by extended stamp elements. Resist may be applied first to the workpiece, the stamp, or substantially simultaneously, in discrete locations, or over the entire surface of either. The resist dewets the substrate completely where desired.

主权项

1. A method of imparting a pattern to a substrate comprising the steps of:
a) providing the substrate and providing a stamp having elastically deformable, raised features arranged in a pattern, each raised feature having a tip with an un-deformed shape and an un-deformed tip width, wherein the stamp has an elastic modulus of less than 0.1 GPa; b) providing, on at least one region of the substrate, an etch resist material that becomes flowable upon heating to a flow temperature; c) disposing the stamp raised feature tips to contact the etch resist material; d) pressing the raised features into the etch resist material, to a degree such that the raised features deform elastically to have a deformed shape that is flatter than the un-deformed shape, the elastically deformed raised features having a tip width that is larger than the un-deformed tip width; e) heating the etch resist material to the flow temperature of the material; f) cooling the etch resist material so that it becomes solid; and g) retracting the stamp to reveal patterned etch resist material covering regions of the substrate, wherein a pattern of the etch resist material includes at least one open region of the substrate not covered by the etch resist material that was previously covered with the etch resist material, said open region corresponding to a raised feature of the stamp and having a width defined by the elastically deformed tip width.