Carrier lifetime measurements in 10 kV 4H-SiC diodes

The minority carrier lifetime τ_p has been measured by open circuit voltage decay (OCVD) and current recovery time (CRT) (or Lax-Neustadter´s) techniques in high-voltage (10 kV) 4H-SiC p⁺n₀n⁺ diodes. The τ_p value measured by OCVD is 1.55 μs at room temperature, which is the highest reported value for 4H-SiC diodes. CRT measurements indicate a homogeneous distribution of carrier lifetime across the diode base without any deteriorated layer between the p⁺-emitter and the n₀-base. Some limitations of lifetime measurements by CRT are discussed.