Evaluation of the characteristics of silicon carbide diodes using transient-IBIC technique (original) (raw)

Transient ion beam induced current (TIBIC) was used to characterise the quality of the electrodes of p þ n and n þ p SiC diodes fabricated on epitaxial 6H-SiC using different fabrication procedures. The diodes were irradiated with 15 MeV O 4þ and 12 MeV Ni 3þ microbeams. Non-uniform charge collection was observed for p þ n diodes with sintered Al electrode, thus, indicating that the electrode of such diode has spatially poor characteristics. On the other hand, for diodes with electrode formed using Al re-evaporation over the sintered area, uniform TIBIC charge maps were observed. Hence, the quality of electrodes of SiC p þ n diodes can be improved by using Al re-deposition procedure. As for n þ p diode, the degradation of Al sintered electrode due to hydrofluoride acid (HF) treatment was revealed by the basis of non-uniformity of the charge map. Since such spatial information cannot be measured using standard electrical means such as current-voltage measurement, the TIBIC technique can be very useful in evaluating the spatial quality of device electrodes.