ANNEALING EFFECTS ON RADIATION-DAMAGED GaN DETECTORS FOR SPACE AND HIGH-ENERGY APPLICATIONS

Mykolas Strigūnas¹, Jevgenij Pavlov¹, Tomas Čeponis¹

¹ Institute of Photonics and Nanotechnology, Vilnius University, Vilnius, Lithuania

[email protected]

Gallium Nitride (GaN) is a wide-direct-bandgap semiconductor material widely utilized in high-voltage electronics, space applications, and medical diagnostic equipment due to its excellent radiation hardness and thermal stability [1-3]. The dual response capability of GaN makes it an attractive candidate for radiation monitoring and high-energy physics experiments, such as ALICE and CMS detectors at CERN [4]. A crucial advantage of GaN-based devices is their potential for optoelectronic characteristic recovery after exposure to radiation, enabling annealing-based restoration instead of costly device replacements. This is particularly beneficial for applications in extreme environments such as space, nuclear reactors, and particle accelerators, where radiation damage can degrade detector performance over time.
In this study, various optical and electrical characterization techniques were employed to investigate the isochronal annealing effects on proton-irradiated metal-organic chemical vapor deposition (MOCVD) GaN. Figure 1a presents the microwave photoconductivity (MW-PC) signal for pristine and irradiated samples during annealing, while Figure 1b displays the time-integrated photoluminescence (TI-PL) spectra for the same samples.

The results reveal significant changes in carrier lifetime and luminescence band characteristics following annealing, demonstrating the material’s potential for self-healing under controlled thermal treatment. These findings indicate that GaN detectors can regain their operational efficiency in radiation-rich environments, enhancing their longevity and reducing maintenance costs in space missions, nuclear facilities, and high-energy physics experiments. The results of this study will be presented at the conference, providing new insights into optimizing GaN-based detectors for extreme operational conditions.

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