Electronic structures of B 2p levels in homo-epitaxial growth boron-doped diamond by soft X-rays absorption spectroscopy

Abstract

Four B-2p in-gap components are observed in B–K XAS spectra using single crystalline boron-doped diamond (BDD) sample. From the polarization dependence of the spectra, the weak peak labeled 1 near the Fermi level is assigned to the hybridized state with C-2p hole state. For the BDD sample grown along 〈111〉 direction, B2 dimer is easily created along the growth direction and compensate carriers. A considerable amount of B–H complex and/or Bn cluster is also present. A growth of the peak-1 area intensity is most important to rise the superconducting transition temperature of BDD.