Patent ID: 6566274
Filing Date: 2003-05-20
Classification: G03F

Abstract:
A method of creating an undercut resist sidewall profile within an opening formed in a positive resist layer disposed upon a transparent substrate, the method comprising the steps of:a. providing a transparent substrate having upper and lower surfaces; b. forming a positive resist layer upon the upper surface of the transparent substrate, the positive resist layer including an uppermost region furthest from the substrate, and including a lowermost region closest to the substrate; c. optically patterning the resist layer by selectively directing light at the resist layer from above the upper surface of the transparent substrate in an area where an opening is to be formed; d. flooding the lower surface of the transparent substrate with light to partially expose the lowermost region of the positive resist layer; and e. developing, following steps c and d, the resist layer a first time by dissolving exposed resist to form at least one patterned opening in the resist layer, the patterned opening having sidewalls, the patterned opening having an enlarged width within the lowermost region of the resist layer adjacent the substrate, due to step d., as compared with the width of such patterned opening within the uppermost region of the resist layer furthest from the substrate.