Microstructural features in amorphous Ge-S-Ga semiconductors

Abstract

Variation of the micro-voids volume (Vh), their formation energy (Eh), and module of elasticity (E) with the composition of amorphous Ge-S-Ga films (as-evaporated and UV-exposed) has been studied. Most pronounced change in these parameters after illumination has been observed at GeS/sub 2/-based compositions with /spl sim/10 at% Ga. The obtained results are compared with those of Ge/sub 90-x/S/sub x/Ga/sub 10/ bulk glasses, taking into account the average coordination number (Z). Specific features at Z/spl sim/2.7 have been found, which can be related to the coexistence of topological and chemical thresholds around this value of Z.