Doping of High-Quality Epitaxial Silicon Grown by Hot-Wire Chemical Vapor Deposition Near 700 ..deg..C

We demonstrate that epitaxial layers with a wide range of controllable dopant densities (7 × 10¹⁵-3 × 10¹⁸/cm³ and 10¹⁷-10¹⁸/cm³ for n-type and p-type, respectively) can be grown on wafer substrates at 700 ± 25 °C by hot-wire chemical vapor deposition. Phosphorus from PH₃ is incorporated into the film more efficiently than silicon from SiH₄, leading to efficient doping. Comparison of Hall carrier concentrations to secondary ion mass spectrometry atomic dopant concentration shows that all incorporated dopants are electrically active. The Hall measurements also reveal that the electron mobility in the P-doped films is close to the impurity-scattering limit for crystal Si wafers at room temperature, indicating that our deposited epitaxial materials are high quality.