Structure of Ge Nanoclusters Grown on Si(001) by Ion Beam Crystallization

摘要

We have studied the temperature effect on structural transitions in the Ge/Si(001) heterosystem (strained wetting layer →hut nanoclusters →dome nanoclusters), characteristic of the ion beam crystallization process. The results demonstrate that, at a given thickness of "quasi-layers" (d_(Ge) = 4 monolayers), increasing the substrate temperature from 350 to 550℃ increases the average size of the hut nanoclusters from 17 to 28 nm and shifts their photoluminescence peaks to the infrared spectral region (from 770 to 720 meV).