Investigation of Ga2O3/diamond heterostructure solar-blind avalanche photodiode via TCAD simulation

A Ga 2 O 3 /diamond separate absorption and multiplication avalanche photodiode (SAM-APD) with mesa structure has been proposed and simulated. The simulation is based on an optimized Ga 2 O 3 /diamond heterostructure TCAD physical model, which is revised by repeated comparison with the experimental data from the literature. Since both Ga 2 O 3 and diamond are ultra-wide bandgap semiconductor materials, the Ga 2 O 3 /diamond SAM-APD shows good solar-blind detection ability, and the corresponding cutoff wavelength is about 263 nm. The doping distribution and the electric field distribution of the SAM-APD are discussed, and the simulation results show that the gain of the designed device can reach 5 × 10 4 and the peak responsivity can reach a value as high as 78 A/W.