Detailed study of scanning capacitance microscopy on cross-sectional and beveled junctions

Abstract

In this work we have done a systematic study with scanning capacitance microscopy (SCM) on cross-sectional and beveled structures. A study was made on the practical problem of contrast reversal as well as on the effect of carrier spilling related to bevel angle, steepness and substrate concentration of the doping profile. A comparison has been made with the results achieved with spreading resistance profiling and also with theoretical predictions. Finally, the junction displacement for cross-sectional and beveled junctions is studied as a function of the applied bias. It is shown that the junction displacement is much smaller on the beveled surface after demagnification. Furthermore, the large extension of the profile along the beveled surface allows us to study the bias induced variation of the SCM signal within the depletion layer in great detail.