Fabrication of Al/n-GaN/p-Si/Al diodes by thermal evaporation and evaluation of effect of gamma irradiation on device properties

This study investigates the impact of gamma-irradiation on the material and device properties of Al/n-GaN/p-Si/Al heterojunction diodes. GaN thin films were deposited on glass and p-Si substrates using thermal evaporation, followed by annealing at 450 degrees C. The diodes were subjected to gamma-irradiation doses of 0, 3, and 6 kGy. X-ray diffraction (XRD) measurements revealed significant structural changes, including phase transitions influenced by radiation. Electrical characteristics were assessed through current-voltage (I-V) measurements within the +/- 2 V range. Notably, the ideality factor for the annealed diodes improved from 6.60 to 4.62 and 3.85 with increased gamma-irradiation. The barrier height was determined to be 0.85 eV, and it did not exhibit a significant change upon gamma-irradiation dose. The results provided valuable insights into the response of heterojunction diodes to radiation exposure, aiding in the understanding and potential improvement of the radiation resistance of GaN-based electronic devices.