Study of Forward Voltage Drift in Diffused SiC PiN Diodes Doped by Al or B
The degradation of diffused SiC PIN diodes during forward-biased operation was studied by first fabricating PIN diodes by diffusion of aluminum or boron into 4H-SiC substrates with n-type 10-15 µm thick epilayers doped by nitrogen up to 5x1015cm-3. The formed diodes were subjected to degradation testing under an applied current density of 200A/cm2 at room temperature. The majority of the Al diffused diodes demonstrated a voltage drift, ΔVf, of more than 2 V, while B-doped diodes showed no significant change in forward voltage. The EBIC mode of SEM was employed to monitor nucleation and expansion of stacking faults.
Roberta Nipoti, Antonella Poggi and Andrea Scorzoni
S.I. Maximenko et al., "Study of Forward Voltage Drift in Diffused SiC PiN Diodes Doped by Al or B", Materials Science Forum, Vols. 483-485, pp. 989-992, 2005