Low-Frequency Noise Characteristics of GaN Vertical PIN Diodes -- Effects of Current and Temperature

TL;DR

This study investigates the low-frequency noise in GaN PIN diodes, revealing how design, current, and temperature influence noise characteristics, with implications for diode quality assessment.

Contribution

It provides detailed analysis of noise behavior in GaN PIN diodes under various conditions, highlighting the recombination noise mechanism and potential quality evaluation methods.

Findings

Most devices exhibit 1/f noise spectrum at moderate currents.

Normalized noise spectral densities are low, around 10^-18 to 10^-16 cm^2/Hz.

Noise peaks occur at temperatures between 375 K and 400 K.

Abstract

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 had rather low normalized noise spectral densities of 10^-18 cm2/Hz -- 10^-16 cm2/Hz (f=10 Hz) at the current density J=1 A/cm2 at room temperature. 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.