Patent ID: 8293326
Filing Date: 2012-10-23
Classification: G03F

Abstract:
1. A method for manufacturing a mask blank having at least a resist film disposed on a surface of a substrate, the method comprising the step of forming said resist film by spin-coating including: a uniforming treatment of dispensing a resist solution on said substrate surface and rotating said substrate at a predetermined main rotation speed for a predetermined main rotation time, so as to primarily form a uniform thickness resist film; and a drying treatment of rotating said substrate at a predetermined drying rotation speed for a predetermined drying rotation time, so as to primarily dry said uniform thickness resist film, wherein, before forming said uniform thickness resist film, a resist solution having an arbitrary concentration or an arbitrary viscosity is selected and an arbitrary drying rotation speed is selected, wherein a relationship is identified, with a visualization treatment, between uniforming-treatment conditions composed of a combination of a main rotation speed with a main rotation time and a film thickness distribution showing a film thickness uniformity of a resist film on said substrate surface under the condition of said selected arbitrary concentration or viscosity resist solution and said selected arbitrary drying rotation speed, wherein said visualization treatment comprises a treatment that prepares a contour map in which a vertical axis indicates the main rotation speed, a horizontal axis indicates the main rotation time, and points corresponding to the same film thickness uniformity within the effective region are bonded by a contour line, a treatment that prepares a bird's eye view drawn by point-plotting while the X axis, the Y axis and the Z axis indicate the main rotation speed, the main rotation time and the film thickness uniformity within the effective region, respectively, or a treatment that is visualized in such a manner that the value of the film thickness uniformity within the effective region continuously varies, under a vertical axis indicating the main rotation speed and a horizontal axis indicating the main rotation time, wherein a uniforming-treatment condition is determined on the basis of said visualization treatment, the uniforming-treatment condition being composed of a combination of the main rotation speed with the main rotation time suitable for obtaining a desired film thickness distribution on said substrate surface, wherein a main rotation speed and a main rotation time for forming said resist film having a desired film thickness is determined by using said determined uniforming-treatment condition, and wherein said uniforming treatment is conducted under said determined main rotation speed and said determined main rotation time.