Damage to epitaxial GaN layer on Al2O3 by 290-MeV 238U32+ ions irradiation

Abstract

Micro-structural characteristics and electrical properties of an n-type GaN epilayer on Al2O3 irradiated by 290-MeV 238U32+ ions to various fluences were investigated using atomic force microscopy (AFM), scanning electron microscopy (SEM), high-resolution X-ray diffraction (HRXRD), and Raman scattering spectroscopy. AFM images show that the nano-hillocks generated, and the diameter and density of the nano-hillocks, increase obviously with increasing ion fluence, accompanied by an increase in surface roughness. SEM images display that the Al, O, and C elements appear on the GaN surface, along with a spiral-like, layered volcanic-cone structure formed at the highest-fluence irradiation. HRXRD reveals that the dislocation density increases, as the lattices gradually expand, and that Ga2O3 was produced with increasing ion fluence. Raman scattering spectra show that no N and Ga vacancies were produced, the free-carrier concentration decreases, while its mobility first increases and then exhibits a significant reduction with increasing ion fluence.

Study of the photoluminescence properties of GaN irradiated with low fluence Ta ions

“…The redshift of E 2 (high) indicates a decrease in N vacancy concentration, while the peak intensity of photoluminescence (PL) increases. The blueshift indicates an increase in N vacancy concentration, accompanied by a decrease in PL peak intensity [3], which is consistent with the PL results. In figure 4(b), the samples under 3 × 10 8 irradiation conditions experience the least amount of stress, and as the fluence increases, the stress on the samples gradually increases.…”

“…Gallium nitride (GaN) is a wide bandgap semiconductor material with excellent properties such as wide bandgap (3.39 eV) and high breakdown field (3 MV cm −1 ) [1,2]. With the development of nuclear and space technology, GaN devices will play a role in new high-tech fields such as highenergy nuclear radiation and aerospace vehicles [3]. For the complex radiation environment, the radiation effect mechanism of wide bandgap semiconductor devices is a challenge for the application of radiation environment.…”

Surface modification by high-energy heavy-ion irradiation in various crystalline ZnO facets

“…The hydrothermally grown single-crystalline ZnO substrates were purchased from the company Crystal GmbH in Germany. For the experiment were used ZnO substrates (10 x 10 x 1 mm 3 ) with three different crystallographic facets polar c-plane (0001) and two non-polar facets a-plane (11)(12)(13)(14)(15)(16)(17)(18)(19)(20) and m-plane . All samples were irradiated by heavy energetic W + ions produced by tandem accelerator Tandetron.…”

“…[8][9][10] It was possible to achieved diverse types self-organised periodic surface structures such as nanodots arrays, nanoholes, hillocks or ripples by ion bombardment of solids realized at normal or grazing incidence angle. [11][12][13] The patterning of the surfaces with features of particular size and shape or preparation of ripples with control of its amplitude is a versatile method to control charge transfer in surface structures and tailor optical properties of semiconductors. [14,15] Simultaneously, the impact of single ion implantation on the crystalline semiconductor (Si, SiC, ZnO) nanostructuring has been shown to be prospective in control of the particular defect creation, functionalise deep-level impurities or formation of single centres with possible application in quantum computing.…”

Medium Energy Carbon and Nitrogen Ion Beam Induced Modifications in Charge Transport, Structural and Optical Properties of Ni/Pd/n-GaN Schottky Barrier Diodes

“…Studies on ion irradiation-induced effects in GaN semiconductor devices have been reported in the literature. Studies on GaN-based electronic devices irradiated by different SHIs have reported the formation of nano-tracks in GaN, development of nano-holes on the GaN surface, and an increase in resistivity of GaN [21][22][23][24]. The ion implantation of GaN by low energy ions reported the doping and amorphization of GaN [25,26].…”