Effect of carbon on lattice strain and hole mobility in Si1- xGe x alloys.

Pseudomorphic Si_{1- x}Ge _x and partially strain compensated $${\text{Si}}_{1 - x - y} {\text{Ge}}_x {\text{C}}_y $$ layers with different Ge and C fractions have been grown at 500 °C by ultra high vacuum chemical vapor deposition on Si (100) substrates. The degree of strain compensation of the layers has been investigated by high resolution X-ray diffraction and simple application of the linear elasticity theory. The surface morphology of the layers has been characterized by atomic force microscopy. The dependence of Si–Si Raman mode vibrations on strain and composition of binary and ternary alloys have been explained with experimental and theoretically calculated results. The Hall hole mobility is found to increase with decreasing compressive strain or effective Ge content in the layer throughout the temperature range of 120–300 K. [ABSTRACT FROM AUTHOR]