Low‐Fluence Neutron Irradiation Effects on AlGaN/GaN HEMTs

Abstract AlGaN/GaN‐based high electron mobility transistors (HEMTs) are ideal candidates for power electronics in consumer, industrial, and space applications. Attributed to their excellent performance in electrical output and chemical stability, AlGaN/GaN HEMTs enable tolerant neutron irradiation in harsh environments. Different from high‐fluence irradiation‐induced device failure, the investigation of low‐fluence neutron irradiation is of great significance to understand the early damage mechanism of HEMTs. Here, the modulated electrical properties are presented of AlGaN/GaN HEMTs under low‐fluence neutron irradiations of 4.5 × 10¹³ and 6.0 × 10¹³ cm⁻². After irradiation, the electrical characteristics of the samples are carefully measured, the output performance of different irradiated devices shows a similar change trend, i.e., almost no changes or only decreased slightly (≤14%) near the knee voltage. For leakage current, the samples irradiated with different fluences show different characteristics, including a slight decrease with the fluence of 4.5 × 10¹³ cm⁻², and a slight increase with the fluence of 6.0 × 10¹³ cm⁻². To further investigate the internal mechanisms, the performance changes are also simulated of the device by using Crosslight software. According to the measurements, it is concluded that the low‐fluence neutron irradiation will initially affect the 2DEG mobility and the surface states of the HEMTs.