High-Temperature Analysis of GaN-Based MQW Photodetector for Optical Galvanic Isolations in High-Density Integrated Power Modules

The indium-gallium nitride (InGaN)/gallium nitride (GaN) multiple quantum well (MQW) structure is demonstrated as a possible solution for high-temperature photodiode applications. High-temperature spectral and noise analysis of InGaN/GaN MQW structure is performed for the potential integration as a detector in future power electronics applications. The spectral response was measured under photovoltaic and bias modes for the temperature range of 77-800 K. A peak spectral responsivity of 27.0 mA/W at 440 nm at 500 K is recorded. The peak external quantum efficiency of the device was calculated to be in the range of 5-8% in the temperature range 77-800 K. The photodetector sensitivity of the structure is quantified using the material figure of merit parameter, D+for different temperature and biased voltages. A peak detectivity of 4 ×108 cm Hz1/2W-1is observed at 800 K with zero bias at 440 nm.