Simulated Annealing Algorithm Application on Inverting Optical Constants of Thin Films

In thin-film thickness wideband monitoring system,in order to eliminate error accumulation effect of layers which have been deposited on layer which will be deposited, the thin-film optical constants of layers deposited must be achieved.Utilizing transmittance spectral curve which has been measured, Simulated Annealing Algorithm is applied on inversion of optical constants n,k,d.For the purpose of increasing optimization speed and algorithm efficiency,the algorithm is improved, exponent dropping temperature rate varies with acceptance probability P ;The finding range of new value is controlled adaptively according to acceptance rate when the dropping temperature is t,then the algorithm is applied on the example that is membrane ZnS is deposited on the substrate of quartz glass , n,k,d are obtained in a shorter time by optimization and their values are satisfying.