Growth and Characterization of High Quality Si 1- x-y Ge x C y Alloy Grown by Ultra-High Vacuum Chemical Vapor Deposition

High quality Si1-x-yGexCy alloy with 2.2% C is grown at a relatively high temperature (760°C) on Si(100) using ultra-high vacuum/chemical vapor deposition (UHV/CVD) system. The samples are investigated with high resolution cross-sectional transmission electron microscope and x-ray diffraction. Compared with Si1-xGex alloys, Si1-x-yGexCy alloys with small amounts of C have much less strain and larger critical layer thickness. The quality of interface is also improved. Relatively flat growing profiles of the film are confirmed by secondary ion mass spectroscopy. Fourier transform infrared spectroscopy is also used to testify that the carbon atoms are on the substitutional sites. It is proved that the UHV/CVD system is an efficient method of growing Si1-x-yGexCy alloys.