Electron Beam Direct Writing Techniques for the Development of Sub-Quarter-Micron Devices

Abstract

This paper investigates a control scheme for tracking the dynamic shapes of structures with limited numbers of voltage channels. Integrated design optimization of voltage channel distribution and control parameters for structural dynamic shape control is formulated as an optimization problem with discrete variables and continuous variables coexisting. A two-level optimization method based on a simulated annealing algorithm is proposed. In the first level, the optimum channel distribution is determined by optimizing the objective function which is the optimal value obtained in the second level. The optimum control parameters are obtained by using a sequential linear least-squares algorithm in the second level. The effectiveness of the present design methodology and optimization scheme is then demonstrated through numerical examples for tracking the dynamic shapes of composite plates.

Direct writing of optical waveguides on PADC substrate by e-beam

“…The fabrication of various optical structures such as gratings, resonators or microguides involves the help of masks that represents some relatively heavy constraints. That is the reason why we use, in this work, the Electron Beam (EB), delivered by a Scanning Electron Microscope (SEM), direct writing technique [8][9][10], on PADC (commercially named CR39), a polymeric material widely used by the optical industry and we now study under EB. Some optical characteristics of the waveguides are reported as a function of the main irradiation parameters (energy and fluence of the EB).…”