Built-in Lens Mask Technology for Generating Three Dimensional Image based on Computational Lithography

A novel technology to create 3D shape image with single exposure to single mask will be presented. The mask is a general mask available for the conventional lithography, but its pattern layout is calculated based on the theory of the built-in lens mask (BILM) technology and totally different from the target object shape. The technology creates the same image as a projection exposure lithography creates just by exposing the mask, because a function performed by lens and mask is embedded into the mask pattern. We will also introduce a concept of the virtual exposure system by which 3D image can be easily designed. BILM covers functions performed by the virtual exposure system, too. We will demonstrate that BILM can create a clear 3D image using examples applying it to i-line proximity exposure through the optical lithography simulation.