Segregation coefficients of various dopants in Si_xGe_1-x (0.93<x<0.96) single crystals

Si-rich Si_xGe_1-x alloys (0.93<x<0.96) heavily doped with B, Ga, In, P, As and Sb were grown by the Czochralski technique. Full single crystals more than 50 mm in length with a maximum diameter of 25 mm were successfully grown. Segregation coefficients of the dopants in the Si-rich SiGe alloys were evaluated based on the variation of carrier concentrations, measured by Hall effect measurements, along the direction of growth of the single crystals. The segregation coefficients of Ga, In and Sb increased drastically in SiGe alloys in comparison with those in Ge and Si crystals. The P segregation coefficient increased, while the B segregation coefficient decreased with increasing concentration in SiGe alloys. The variation of dopant segregation coefficients induced by the incorporation of Ge atoms into Si may be attributed to elastic interaction due to the size misfit among the relevant atoms.