Superconductor-to-insulator transition in boron-doped diamond films grown using chemical vapor deposition

The critical concentration of superconductor-to-insulator transition in boron-doped diamond is determined in two ways, namely, the actual doping concentration of boron and the Hall carrier concentration. Hall carrier concentrations in (111) and (001) films exceed the actual doping concentration owing to the distortion of the Fermi surface. The high critical boron concentration in (110) films is owing to the effect of the high concentration of interstitial boron atoms. A boron concentration of 3×10²⁰ cm^-3 in substitutional site is required for inducing superconductivity in diamond.