High Temperature Behaviors of 1-2.5 μm Extended Wavelength In0.83Ga0.17As Photodetectors on InP Substrate

The dark current and the photo response characteristics of extended wavelength In0.83Ga0.17As/InP photodetectors (PDs) with n-In-0.83 Ga-0.17 As absorber doped to 8 x 1(15), 7 x 10(16) and 1 x 10(17) cm(-3) are investigated in an elevated temperature range of -40 to 100 degrees C. The lightly doped PD exhibits a lower (higher) dark current than the heavily doped PD at temperatures higher (lower) than 30 degrees C. The photocurrent, the spectral responsivity and the blackbody response voltage for the heavily doped PD rapidly decrease at temperatures higher than 30 degrees C, while remain almost unchanged until 90 degrees C for the lightly doped PD. The trend of the intermediately doped PD is between the two. In contrast, a consistently increasing trend of the dark noise over the whole measured temperature range are observed for three PDs. Theoretical calculations indicate such behaviors are essentially related with the temperature-dependent variation of the Shockley-Read-Hall lifetimes under different doping concentration.