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In this experiment, a three dimensional structure analysis was carried out to examine the surface defectsof semiconductor made artificially on known scale. It was investigated the three dimensional imaging according to thesample depth and the thermal diffusivity as wel as the carier transport properties. The thermal diffusivity measurementof the intrinsic GaAs semiconductor was also analyzed by the difference of frequency-dependence photoacoustic signalsfrom the sample surface of different conditions. Thermal properties such as thermal difusion length or thermal difusivityof the Si wafer with and without defects on the surface were obtained by interpreting the frequency dependence of thePA signals. As a result, the photoacoustic signal is found to have the dependency on the shape and depth of the defectsso that their structure of the defects can be analyzed. This method demonstrates the possibility of the application to thedetection of the defects, cracks, and shortage of circuits on surface or sub-surface of the semiconductors and ceramicmaterials as a nondestructive testing(NDT) and a nondestructive evaluation(NDE) technique.