Fabrication of Diffractive Optical Elements by Electron Beam Lithography

Diffractive optical elements (DOEs) are an important component in the success of optical Microsystems. Electron beam lithography is a key part of fabricating these elements with submicron feature dimensions. This thesis presents work done on the development of a process for the fabrication of multilevel diffractive optics in glass substrates using this method. This project investigates various challenges involved in the process, addresses possible problems that may arise and proposes and investigates solutions to resolve them. Sources of possible error in the creation and transfer of the patterns are identified and methods of eliminating or minimizing these errors are presented. Some of the main sources of error arise from charging due to electron accumulation and alignment issues during electron beam lithography.