X-ray absorption near edge structure and extended X-ray absorption fine structure studies of P doped (111) diamond

The P dopant site control in diamond is critical to achieve high mobility n type channels and high concentration n+ layers for power device applications. In this study, the P doped diamond films grown by three institutes with varying hydrogen and dopant concentrations were analyzed by X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS). By XANES, the film with high H concentration (4.0 x 10(19) cm(-3)) was estimated to show a higher peak intensity of 2147.7 eV than that of a low H concentration film. H was likely to be incorporated in the diamond as P-H at the substitutional sites under H rich growth condition. Another film showed considerably low peak intensities at 2147.7 and 2148.6 eV because of the substitutional with H and substitutional sites, respectively. The EXAFS result revealed that the first nearest neighbor distance is slightly shifted from the substitutional to interstitial site. The low P concentration film showed different types of energy profiles, particularly in the high energy region, indicating that dopant sites change with dopant concentration. Overall, the P dopant site is likely to be influenced by the machine system, H and P concentrations.