Abstract
This experiment can be divided into two major parts, The first part is the development of GaN materials used in photodetectors,The second part is the application of gallium nitride materials in the development of high electron mobility transistors. In the photodetector section, two different matrix samples are used, The dry-etching technique was used to define the p-n interface and then Ti/Al and Ni/Au were deposited on the thermal evaporator, After rapid thermal annealing, an Ohmic contact is formed to complete the p-i-n diode. After the diodes are completed, the passivation technology is used to suppress the leakage current caused by the defects of the wafer itself and the etching bombardment, The antireflection layer is designed again to increase the entrance of effective photocarriers. The passivation technology adopts ALD, SOG, and PECVD growth films, respectively, to cover sidewalls and surface defects to achieve the effect of suppressing leakage current, Passivation technology, operating at -5V, the leakage current can be suppressed at 10-14A. The anti-reflection layer is ALD, PECVD, through the film thickness modulation, reduce the light source reflection, through the anti-reflection layer design, the responsivity can come to 10-2A/W. The second part is the development of high electron mobility transistors, Using two different sources of samples, compare the electrical characteristics of the two samples. The dry etching technique was used to define the drain, source and gate electrodes and punch through the 2DEG. The electron gun deposition machine was used to plate Ti/Al/Ti/Au, After rapid thermal annealing, an Ohmic contact is formed, and then Ni/Au is plated on a thermal evaporator to form a Schottky contact to complete the high electron mobility transistor, The passivation process adopts ALD with high coverage and high density as passivation film, Compare the properties after passivation. After passivation, in addition to reducing the leakage current, the saturation current density and the Gm value have been improved, The saturation current is increased from 200 mA/mm to 310 mA/mm, and the Gm value is increased from 85 ms/mm to 107 ms/mm.