The influence of heat treatment at and above 1100 degrees C on thin erbium-rich silica layers embedded in silica has been studied experimentally by secondary ion-mass spectrometry and cross-sectional transmission electron microscopy. Redistribution of erbium atoms is observed at these temperatures, and formation of erbium-rich. precipitates is seen to occur if the erbium concentration exceeds similar to 0.01 at. %. These precipitates are observed to coarsen and subsequently dissolve with increasing annealing time. Moreover, self organization of precipitates has been observed in the form of layering of the precipitate ensemble.
Bibliographical noteCopyright (1999) by the American Physical Society.