Phosphorus doping in Si_1-x-yGe_xC_y epitaxial growth by low-pressure chemical vapor deposition using a SiH₄-GeH₄-CH₃SiH₃-PH ₃-H₂ gas system

Phosphorus doping in Si_1-x-yGe_xC_y(0 ≤ x ≤ 0.78, 0 ≤ y ≤ 0.016) epitaxial growth on Si(100) at 550°C by ultraclean hot-wall low-pressure chemical vapor deposition using a SiH₄-GeH₄-CH₃SiH₃-PH ₃-H₂ gas system is investigated. The relationship among the Ge, the C fraction, the P concentration (C_P), the deposition rate, and the deposition conditions in the P-doped Si_1-x-yGe_xC_y epitaxial growth under the surface reaction-limited regime is experimentally obtained, and is explained by the modified Langmuir-type adsorption and reaction scheme. The relationships among the carrier concentration, the C_P, and the resistivity in the P-doped Si_1-x-yGe_xC_y for various Ge and C fractions are also presented. The carrier concentration of the P-doped Si_1-x-yGe_xC_y with low Ge and C fractions ( x ≤ 0.48 and y ≤ 0.0046) is nearly equal to C_P below approximately 2 × 10²⁰ cm^-3. With increasing Ge and C fractions, the film has electrically inactive P atoms independent of C_P. The existence of C (y ≥ 0.0048), in the film reduces the Hall mobility.