Temperature-induced obliteration of sub-oxide interfaces in amorphous GeO

The temperature-induced phase separation of native amorphous germanium monoxide, a-GeO, into Ge and GeO2 was studied by measurements of the Ge K-edge employing partial fluorescence yield detection. In the native a-GeO samples a significant amount of sub-oxides was found. This sub-oxide content decreases with increasing annealing temperature. At elevated temperatures the formation of nanocrystals was observed. The results indicate a structure of a-GeO which consists of nanoscaled Ge and GeO2 clusters separated by sub-oxide interfaces.