Characteristics of B‐doped Si1 − x Ge x Growth Rates by Chemical Vapor Deposition Using Si2 H 6, GeH4, and B 2 H 6 Gases

Low temperature heteroepitaxy of highly B‐doped on Si by low pressure CVD has been investigated from the viewpoint of growth rate. The growth temperature was 550–730°C, and the concentration of B was 10 18 –10 21 cm −3 . For the undoped and B‐doped , the growth rate was limited by the supply of and to the surface at temperatures above 630°C and by the desorption of hydrogen from the surface at temperatures below 630°C. The activation energy of the growth rate was 2.0 eV for undoped alloy below 630°C. A reduced activation energy was found for in situ B‐doping. The growth rates of alloy (the surface reaction rates of and ) increase with increases in the surface density of B deposited by the decomposition of on the surface. The deposition rate of B is determined only by the quantity of supplied to the surface and does not depend on the composition of the alloy surface layer or the growth temperature.