Investigation of Low-Frequency Noise Characteristics of GaN Vertical PIN Diodes at Elevated Temperatures

Development of the next generation of GaN PIN diodes for high-power electronics requires effective methods for assessing materials and device quality. Low-frequency noise measurements have been widely used for the characterization of defects in various semiconductor devices, and for testing their reliability [1]. The noise level and its current or gate voltage dependence in the field-effect transistors can be used to compare the quality of the device structures. Temperature dependence of the low-frequency noise is often used to determine its origin and physical mechanism. Accurate knowledge of the specific semiconductor devices’ noise characteristics is also required for circuit-level modeling. In this talk, we report low-frequency noise characteristics of vertical GaN PIN diodes, focusing on the effects of the diode design, current, and temperature. The as-grown and regrown diodes, with and without surface treatment have been studied. The noise in most of the GaN devices had a characteristic 1/f spectrum at high and moderate currents, while some devices revealed generation-recombination bulges at low currents (f is the frequency). The predominant trend of the noise spectral density, S, dependence on the current was S~I. All tested GaN PIN diodes revealed rather low normalized noise spectral densities. The noise temperature dependences at different currents revealed peaks at T=375 K – 400 K. Temperature, current, and frequency dependences of noise suggest that the noise mechanism is of the recombination origin. We argue that the noise measurements at low currents can be used to efficiently assess the quality of GaN PIN diodes.<br/><br/>The work at UC Riverside and Rice University was supported by ULTRA, an Energy Frontier Research Center (EFRC) funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences under Award # DE-SC0021230. S.R. is partially supported by CENTERA Laboratories in a frame of the International Research Agendas program for the Foundation for Polish Sciences co-financed by the European Union under the European Regional Development Fund (No. MAB/2018/9).<br/><br/>[1] A. A. Balandin, Noise and Fluctuations Control in Electronic Devices (American Scientific Publishers, 2002); [2] S.L. Rumyantsev, et al., J. Appl. Physics, 100, 064505 (2006).