Study On Defects Of ?-Ga₂O₃ Crystal Induced By Charged Particle Radiation

As the fourth-generation semiconductor material,gallium oxide has the characteristics of strong radiation resistance,large forbidden band width and easy regulation of performance.At present,it has broad application prospects in the fields of deep ultraviolet detection and optical detection.At present,the structural evolution of gallium oxide under irradiation conditions has become the primary concern of academic circles at home and abroad.It is of great practical significance to study the defect behavior and performance effects of gallium oxide after irradiation.In this paper,single crystal ?-Ga2O3 materials were used as the irradiation source,and four particles of 1 MeV electron,50 MeV proton,400 keV proton and 400 keV nitrogen ion were used as the irradiation source.The effects of particle species and irradiation fluence on the optical properties and defects of ?-Ga2O3 were investigated.In this paper,based on SRIM,the defect distribution after particle irradiation is simulated,and the optical properties of gallium oxide are characterized by spectrophotometer and photoluminescence spectroscopy.Using Raman spectroscopy,photoluminescence spectroscopy and X-ray photoelectron spectroscopy to investigate the changes of internal defects after gallium oxide irradiation.According to the simulation results,the defects formed by 1 MeV electrons and 50 MeV protons are more evenly distributed,and 400 keV protons and 400 keV nitrogen ion defects are concentrated on the surface.1 MeV electrons have the greatest influence on the transmittance of ultraviolet band,and 50 MeV protons,400 keV protons and 400 keV nitrogen ions have a great influence on the transmittance of visible light.Unirradiated gallium oxide has two red emission bands at 700 nm and 625 nm,and the intensity increases as the irradiation fluence increases.400 keV protons and 400 keV nitrogen ions produce new bands at 584 nm when the fluence is high.This shows that the photoluminescence properties of gallium oxide can be regulated by irradiation or ion doping.According to Raman spectroscopy,it is found that gallium oxide has an influence on both gallium atoms and oxygen atoms after irradiation.Combined with photoluminescence spectroscopy,the vacancy level of the gallium atom is at 2.0 eV,and the oxygen vacancy level is at 1.76 eV.At the same time,400 keV protons and 400 keV nitrogen ions produce interstitial oxygen atoms with an energy level of 2.2 eV when the fluence is large.According to the X-ray electron spectroscopy,it is found that protons of any energy combine with oxygen to form an O-H bond.After the irradiation,the valence state of the gallium atom is basically unchanged,so it can be inferred that the vacancy of the gallium atom may have three negative charges.Studies have shown that all four particle irradiations have an effect on the transmission of gallium oxide.Irradiation can modulate the photoluminescence intensity of gallium oxide and create new bands of light through interstitial atoms.Oxygen atoms in gallium oxide not only form vacancies and interstitial atoms,but also combine with incident particles to create new defects.Gallium atoms have high displacement energy and are not easy to form defects.However,elements with high incident energy and easy to bind to gallium atoms may combine with gallium atoms after irradiation.