Photoacoustic frequency transmission technique: Electronic deformation mechanism in semiconductors

Abstract

A quantitative analysis of the electronic deformation (electronic strain) contribution to the photoacoustic signal in semiconductor samples was done. The photoacoustic (PA) effect was investigated as a function of the modulation frequency in a transmission detection configuration. The theoretical model for this configuration was given for the thermal and elastic processes besides the carrier transport characteristic and the relation for electronic elastic deformation was derived by the theory of the elastic thin plate vibrations. Analysis showed that the electronic deformation mechanisms can have an important infleucne on the PA signal in the frequency range typical for gas-microphone detection. The experimental photoacoustic data for Si samples were measured and they exhibited a satisfactory agreement with the theoretical model.