The role of the ion implanted emitter state on 6H-SiC power diodes behaviour. A statistical study.

M Lazar (1, 2) , G Cardinali (3) , C Raynaud (1, 2) , A Poggi (3) , Dominique Planson (1, 2) , R Nipoti (3) , J P Chante (1, 2)

1 CEGELY - Centre de génie électrique de Lyon
2 INSA Lyon - Institut National des Sciences Appliquées de Lyon
3 CNR - Consiglio Nazionale delle Ricerche [Bologna]

Following a simulation work on design 6H-SiC p+n power diodes, two device runs were fabricated with Al ion implanted emitter and JTE periphery. The implantation temperatures of the emitter were different: room temperature (RT) and 300°C. A systematic characterisation in forward (up to 5V) and reverse bias (down to -50V) was performed. Breakdown voltages were also measured on a part of diodes. The emitter state after implantation and annealing seems to be important for the diode behaviour in forward and in reverse polarisation also. For the 300°C implanted wafer higher current densities (200 A.cm-2 at 5V) are obtained in forward bias, with a better distribution, more homogenous, showing better doping activation and layer quality. For the 300°C implanted diodes, fewer diodes with high leakage currents is obtained and those with the smallest emitter and the longest JTE sustain more than 1100V, with a breakdown voltage value close to the simulated value and independent on the testing ambient. This indicates a breakdown in the bulk, confirmed by its voltage value decrease for the RT implanted diodes. This is due to the presence of an amorphous layer after implantation and thus residual defects at the emitter-epilayer junction interface.

Domaines: Energie électrique

M Lazar, G Cardinali, C Raynaud, A Poggi, Dominique Planson, et al.. The role of the ion implanted emitter state on 6H-SiC power diodes behaviour. A statistical study.. International Conference on Silicon Carbide and Related Materials (ICSCRM 2003), Oct 2003, Lyon, France. ⟨hal-02941715⟩