Visible Blind 4H-SiC P+-N UV Photodiode Obtained by Al Implantation

This paper reports the electrooptical characteristics of ultraviolet light-sensitive 4H-SiC p(+)-n junction photodiodes obtained by aluminium (Al) ion implantation on low-doped n-type epilayers. A low dark current density (G 1 nA/cm(2) at -100 V) was measured on 1-mm2 area devices up to 90 degrees C. A peak responsivity of 0.11 A/W at 280 nm corresponding to a quantum efficiency of about 50% and a visible blindness > 10(3) were demonstrated. The absence of optically active defects and nitrogen donor-aluminum acceptor pair recombination centers was monitored by optical measurements in the visible range.