Preparation And Performance Study Of Solar Blind Detector Based On Intrinsic And Ti-Doped Ga₂O₃ Thin Film

With the continuous development of semiconductor science and technology,existing semiconductor devices are facing more and more problems.In terms of high-voltage and high-power devices,ultra wide bandgap semiconductor materials have unique advantages.Ga₂O₃ is one of the third-generation ultra wide band gap semiconductor materials,which has high breakdown electric field,high electron mobility and high Bari plus value.At the same time,Ga₂O₃ also has a high transmittance in the visible light range,and has good application prospects in photodetectors,power devices,and gas sensors.This article mainly studies Ga₂O₃ thin films prepared on Al₂O₃ and Si substrates.First of all,Ga₂O₃ thin films were prepared on Al₂O₃ substrate by Magnetron sputtering and tube furnace annealing process,and the effects of annealing heating rate,annealing temperature and annealing atmosphere on Ga₂O₃ thin films were investigated.The experiment found that fast annealing and heating rate are more conducive to the preparation of Ga₂O₃ thin films with better crystal quality.Therefore,in industrial production,production efficiency can be improved by appropriately increasing the heating rate of the annealing process.Meanwhile,the experimental results indicate that the annealing atmosphere has a significant impact on the crystallization quality and electrical properties of Ga₂O₃ thin films.The study in this article found that air annealing is beneficial for the crystallization of Ga₂O₃ thin films and can reduce their conductivity,but there is almost no photocurrent response to ultraviolet light.The vacuum annealed samples exhibit good photocurrent response to ultraviolet light.Then,this article prepared three types of Ga₂O₃ optoelectronic devices on Si substrates,namely Pt/Ga₂O₃/Pt MSM structure,n-Ga₂O₃/p-Si heterojunction structure,and n-Ga₂O₃/i-Ga₂O₃/p-Si pin structure.The MSM structure device has a certain UV light response;Heterojunction devices have almost no UV light response;The devices with pin structure exhibit good optical response characteristics at appropriate Ti doping concentrations.For devices with a 4.32 at%Ti doping concentration pin structure,the response can reach 0.65 A/m W under-10 V bias voltage.At the same time,the 4.32 and 6.15 at%Ti doped pin structure devices show good reverse withstand voltage characteristics,and their reverse breakdown voltages can reach-170and-160 V,respectively.At the same time,the devices of this structure use the normal temperature Magnetron sputtering process,and are prepared on Si substrates.They are compatible with the existing process and have low industrial production costs,so they have good commercial application prospects.