Patent ID: 6881534
Filing Date: 2005-04-19
Classification: B82Y,G03F,G11B

Abstract:
1. A method of forming a mask to be used for forming a patterned thin film, the mask including: an upper layer made of a resist and having a specific width; and a lower layer having a width smaller than the width of the upper layer; the method comprising the steps of: forming a first layer on a base layer, the first layer being made of a material that is soluble in a developer and has a higher removal rate in ashing than the resist; forming a second layer made of the resist on the first layer; exposing the second layer to light for forming a latent image of specific pattern; developing the second layer having undergone the exposure and dissolving part of the first layer using the developer, so that the remainder of the first layer has a width equal to or greater than that of the second layer having undergone the development; and performing ashing on the remainder of the first layer and the second layer having undergone the development, so that the first layer having undergone the ashing has a width smaller than that of the second layer having undergone the ashing, to make the first layer having undergone the ashing serve as the lower layer and the second layer having undergone the ashing as the upper layer.