AFM Characterization of the Initial Growth Stages of CdTe on Si(111) Substrates

Abstract

We report on the growth and characterization of very thin CdTe layers on Si(111). The samples were grown by hot wall epitaxy on Si substrates treated by a diluted HF solution. Using this process, good quality CdTe layers can be grown, with the whole process being conducted at temperatures below 300 °C. The samples were grown at a very low growth rate of about 0.02 Å/s in order to investigate the nucleation process using atomic force microscopy. Our measurements show that this system follows the Volmer–Weber growth mode, with the nucleation of isolated CdTe islands on the Si substrate surface. We describe the size and density distribution of these islands as a function of substrate temperature. The results show that the Volmer–Weber growth mode can be successfully used to obtain self-assembled quantum dots of CdTe on Si using an inexpensive growth technique.