CVD diamond metallization and characterization

In this study we compared three diamond substrate grades: polycrystalline, optical grade single crystal, and electronic grade single crystal for detector application. Beside the bulk type, the choice of contact material, pre-treatment, and sputtering process details have shown to alter significantly the diamond detector performance. Characterization of diamond substrate permittivity and losses indicate grade and crystallinity related, characteristic differences for frequencies in 1 kHz-1 MHz range. Substantial grade related variations were also observed in surface electrostatic characterization performed by contact potential difference (CPD) mode of an atomic force microscope. Study of conductivity variations with temperature reveal that bulk trap energy levels are also dependent on the crystal grade.