Growth of SiGe Films by Cold-wall UHV/CVD Using GeH4 and Si2H6

An ultrahigh vacuum chemical vapor deposition (UHV/CVD) system is introduced. SiGe alloys and SiGe/Si multiple quantum wells (MQWs) have been grown by cold-wall UHV/CVD using disilane (Si 2H 6) and germane (GeH 4) as the reactant gases on Si (100) substrates. The growth rate and Ge contents in SiGe alloys are studied at different temperature and different gas flow. The growth rate of SiGe alloy is decreased with the increase of GeH 4 flow at high temperature. X-ray diffraction measurement shows that SiGe/Si MQWs have good crystallinity, sharp interface and uniformity. No dislocation is found in the observation of transmission electron microscopy (TEM) of SiGe/Si MQWs. The average deviation of the thickness and the fraction of Ge in single SiGe alloy sample are 3.31% and 2.01%, respectively.