The Study Of The Growth And Optical Properties Of Beta-Ga₂O₃/p-Si Heterostructures

As the ozone layer has a great absorption coefficient in 200?320nm UV light,n there is little of ultraviolet radiation of this band near the ground,so we call this band solar blind ultraviolet.The detection of ultraviolet light in the solar blind,have the advatage of anti interference and work around the clock,have a strong demand of application in the missile early warning,rocket tail flame detection,space exploration,corona detection,Bio Medical and other fields.Ga2O3 is a kind of direct band gap of wide band gap oxide semiconductor,its optical band gap between 4.2eV-4.9eV.Its good chemical stability and thermal stability,and at high temperature particularly sensitive to certain gases.It has a strong research value in the solar blind UV detector,high temperature gas sensor and deep ultraviolet transparent conductive oxide.It has become a research hotspot in china and internetional.In this thesis,we use pulsed laser deposition technique to grow high quality ?-Ga2O3 thin film on p-Si substrate to construct the ?-Ga2O3/p-Si heterojunction photoelectric detector and study its photoelectric properties.In this paper,the research background,structure and properties of ?-Ga2O3 are studied in detail.The growth method and photoelectric detection principle are deeply studied,and some results are obtained as follows:1.By optimizing the growth parameters,(-201)-oriented?-Ga2O3 films were obtained on p-Si substrate by laser molecular beam epitaxy;2.The Ti-Au and Au electrodes were deposited on the double surface of the ?-Ga2O3/p-Si by magnetron sputtering technology,and the ?-Ga2O3/p-Si heteroj unction optoelectronic detecting prototype device was obtained;3.The ?-Ga2O3/p-Si heterogeneous photoelectric performance of photoelectric detection prototype device were tested.The I254/Idark is about 1000,the response time is 1.79s,the responsivity is 370A/W,the external quantum efficiency is 1.5×105%;4.The photoelectric performance of the ?-Ga2O3/p-Si heterojunction photoelectric detector is systematically analyzed.The results indicated that the response of the device to 254nm was related to the avalanche process in the beta ?-Ga2O3/p-Si heterojunction.