delta-doping in diamond

delta-Boron-dopod homoepitaxial diamond films grown by microwave CVD were o ptimized for field effect transistor application to obtain steep profiles. The critical growth steps of the delta-doped device structures were analyze d and improved using mass spectrometry gas analysis, determining growth- an d etch rates, hall-effect-measurements, elastic recoil detection and conduc tivity measurements. Optimized growth procedures were obtained and residual doping in the gate control layer was compensated using nitrogen. This resu lts in a novel lossy dielectric Junction FET channel with high sheet charge activation and high drain current densities at moderate operation temperat ures of 200 degrees C. (C) 1999 Elsevier Science Ltd. All rights reserved.