Study On The Structure And Epitaxy Technology Of PIN Photodetectors Based On InP Substrate

Early photodiode was made up of a reverse biased PN junction. whoseabsorption zone was narrow, Photon wasn’t enough absorbed by absorption zone.Minority carriers was easily recombined in the p diffusion region or n diffusion region.which also reduced the photodiode’s responsivity. To solve this problem, PIN infraredphotodetector is proposed. PIN infrared photodetector is aslo made up of a reversebiased PN junction.The difference between PIN infrared photodetector and anordinary photodiode is space charge. There is a low-doped i-layer between the heavilydoped p region and the heavily doped n region in PIN infrared photodetector.whenvoltage is applied, the i layer is the space charge. photon-generated carriers are drivenby the voltage through space charge.which improve the response speed of the device.PIN infrared photodetector is still widely used in near infrared photodetector. owingto making technology simple and fast response speed. This article Study on the effectof parameters on infrared detector and obtain the optimal Thickness for PIN infraredphotodetector.As the theoretical basis of PIN infrared photodetector. In theexperiments,we verify the doping of InP/InGaAs materials and produce PIN infraredphotodetector. Basic test is carried out and the corresponding conclusion is drawn.Themain content of this thesis include Four aspects as follow1. The basic theory of Infrared detector was introduced. The related factors ofinfrared detector were simulated and calculated and the optimal thickness wasacquired.2The fundamental of MOCVD was introduced. Materials growth experimentwas illustrated. Introduced the made out of MOCVD system and The basic theory oftesting tools. the growth temperature and thickness was regulated.3. explored the doping rules of InP and InGaAs solved the problem that the Ptype ohmic contact was solved by diffusion.4. The varied doping method was raised to solve the influence of intrinsic layerby InP doping.the High quality InGaAs material was grown5. Optimized epitaxial process，Significantly improved the performance ofphotoelectric detector...