Dopant profile measurements in ion implanted 6H–SiC by scanning capacitance microscopy

Abstract

Two-dimensional carrier profiles were determined in ion implanted 6H–SiC by scanning capacitance microscopy (SCM). The measurements were performed on cross-section using metal covered Si tips. The implantations were performed into a SiC substrate at a temperature of 500 °C (on both n and p-type material) with 200 keV N + and 300 keV Al + ions in the fluence range 1×10 14–2×10 15 cm −2 . Annealing processes were carried out at 1300 °C in argon flux. The defect profile before and after thermal processes were analysed with Rutherford backscattering spectroscopy and the residual defects were characterised by transmission electron microscopy. The integration of carrier profiles measured by SCM gives an electrical dopant activation of 10% for N implanted layer and of 4% electrical activation in Al implanted layer. The carrier profiles and the active fraction of implanted atoms are correlated to the concentration and structure of residual defects.