The Cadmium-Telluride (CdTe) semiconductor, which can be used at normal temperatures without cooling, was recently developed for the measurement of X-ray spectra. In this paper, we calculated the energy-dependent responses of CdTe semi-conductor detectors to X-ray photon beams by means of the Monte Carlo simulation. The CdTe semiconductor showed higher K-escape fractions and lower photo-peak efficiencies than the high purity Germanium (HPGe) semiconductor that has generally been used for X-ray spectra measurements. Therefore, it is assumed that the output spectra measured by the CdTe detector are more distorted than those measured by the HPGe detector. The X-ray spectra measured by CdTe semiconductor detectors must be corrected to account for the energy dependent response of CdTe.
