Self-limiting growth of ZnS on Si substrates at a growth rate of 0.7 monolayers per operating cycle by atomic layer epitaxy using MOCVD

摘要

ZnS films were grown on (100) Si substrates by atomic layer epitaxy (ALE) using a metal-organic chemical vapor deposition system. We studied the growth rate as a function of the substrate temperature and the flow rates of DMZn and H_2S. The growth rate was kept constant at 0.7 monolayers per cycle and was independent of substrate temperature in the range 125-225℃, and of the mole fractions of both DMZn and H_2S. Although the "fractional ALE" growth does not produce a two-di-mensional surface, SEM micrographs show smooth ZnS films with the atomic ratio of S:Zn very close to unity.