V and Ti doping in 4H-SiC epitaxy for reduction of carrier lifetimes

Epitaxial growth of 4H-SiC with intentional V or Ti doping was performed to obtain short minority carrier lifetimes, using VCl
₄
or TiCl
₄
as the doping sources. The doping efficiencies and quality of the epilayers were compared for H
₂
+SiH
₄
+C
₃
H
₈
and H
₂
+SiH
₄
+C
₃
H
₈
+HCl gas systems. The addition of V or Ti in highly N-doped epilayer demonstrated very short minority carrier lifetimes of 20-30 ns at 250°C.