CO2 laser radiation detection in compensated germanium

Abstract

We report the results of experimental study of infrared radiation detection in a bulk of compensated germanium. Au or Ni with deep levels in the forbidden energy gap was used as compensating impurities. In spite of great difference in their activation energies the change of electrical resistance of the samples under CO2 laser illumination indicated the similar rise of carrier density in the valence band which can not be explained only by means of direct hole activation from these levels. The DC measurements have shown the activation character of the electrical conductivity of compensated semiconductors. Evaluation of spatial quantity of in-homogenates in compensated semiconductors confirmed the importance of energetic bands bending due to the existence of ionised impurities complexes for infrared detection.