Preliminary Investigation of Laser Induced Photoconductivity in 4H-SiC PiN Diodes and HPSI Substrate

We present photoconductivity experiments on a 4H-SiC diode and on 4H-SiC high purity semi-insulating (HPSI) substrate. These devices have been tested over a wide optical wavelength range: 355 nm to 820 nm. The penetration depth of optical wavelength has been estimated from spectrophotometer measurements. Photoconductivity regime has been studied at low electrical field for both devices and photoconductivity efficiency has been compared to Si switches.