Effect of Annealing on the Behavior of Oxygen Dissolved in Germanium and Optical Properties of Single Crystals

The annealing effect in the temperature range from 350 to 450 ∘C on the behavior of interstitial oxygen O i dissolved in germanium and on optical properties of single crystals has been investigated by Fourier transformed infrared spectrometry. It was found that oxygen band maximum of 843 cm−1 shifted toward the 856 cm−1 with oxygen concentration increasing after annealing at the oxygen partial pressure ranged from 1 to 103 Pa. The annealing at lower P O2 values led to the decrease of 843 cm−1 band intensity due to the formation of thermal donors (TD) on the basis of dissolved oxygen atoms O i . It was established that TD formation and the decrease of unbound oxygen concentration affected optical properties of the crystals.