EPR study on amorphous germanium oxygen, deposition angle, annealing, and substrate temperature effects

The influence of various deposition parameters, especially oxygen pressure and deposition angle, on the a‐Ge EPR spectra is studied. In most the cases the results corroborate those already obtained by other authors with other methods (such as conductivity). Two different mechanisms are discussed to explain the spin density decrease: saturation of defects by introducing oxygen and decrease of the defect concentration by structural rearrangements with annealing or substrate temperature increase. At suitable annealing conditions a spin density increase suggests the formation of defects such as multivacancies. The comparison of the EPR line thus obtained with the initial one shows that the defects formed during the evaporation of the purest samples are the same. The EPR line is inhomogeneous.