Effects of radiation and temperature on gallium nitride (GaN) metal-semiconductor-metal ultraviolet photodetectors

Abstract

The development of radiation-hardened, temperature-tolerant materials, sensors and electronics will enable lightweight space sub-systems (reduced packaging requirements) with increased operation lifetimes in extreme harsh environments such as those encountered during space exploration. Gallium nitride (GaN) is a ceramic, semiconductor material stable within high-radiation, high-temperature and chemically corrosive environments due to its wide bandgap (3.4 eV). These material properties can be leveraged for ultraviolet (UV) wavelength photodetection. In this paper, current results of GaN metal-semiconductor-metal (MSM) UV photodetectors behavior after irradiation up to 50 krad and temperatures of 15°C to 150°C is presented. These initial results indicate that GaN-based sensors can provide robust operation within extreme harsh environments. Future directions for GaN-based photodetector technology for down-hole, automotive and space exploration applications are also discussed.

Irradiation effects of graphene-enhanced gallium nitride (GaN) metal-semiconductor-metal (MSM) ultraviolet photodetectors

“…The graphene-based photodetectors are irradiated and then characterized under UV light and dark conditions to observe the impact of irradiation. In our previous work, we showed that GaN MSM photodetectors could perform up to 50 krad TID 15 and that graphene MSM electrodes on hybrid silicon dioxide/GaN substrates could function up to 200 krad TID. 16 In the latter case, trapped charges generated in the irradiated SiO 2 thin film seemed to affect device performance by saturating the photocurrent, so here attempt to mitigate those effects with direct contact of graphene and GaN devices.…”