Study On The Structure Optimization Of Broad Spectral Photodiodes Based On Silicon-organic Semiconductor Heterojunction

Optical sensing from the ultraviolet?UV?to the near infrared?NIR?range have broad applications including imaging,telecommunications,biomedicine,environmental monitoring and defense military.It is desirable to have a photodiode with a response spectrum covering a broad spectral range from UV to NIR.However,commercially available solid-state photodiodes have relatively narrow response spectra.For example,silicon photodiodes are only good for the visible/NIR range,while photodiodes made of SiC are generally selected for UV sensing.Organic semiconductor materials have the advantages of low cost,simple preparation process and good flexibility,and have a wide range of selectivity.Therefore,combining silicon materials and organic materials and using complementarity of absorption spectra between different materials to manufacture a silicon-organic semiconductor heterojunction broad spectral photodiode has become a method for realizing a broad spectral photodetector.This dissertation mainly focuses on the manufacture of silicon-organic semiconductor heterojunction broad spectral photodiodes,and optimized the device structure,systematically test and characterized the device,and completed the mechanism analysis and discussion.This dissertation mainly includes the following two aspects of research content:?1?A photodiode based on the structure of p-type silicon?p-Si?/phthalocyanine?CuPc?:3,4,9,10-perylenetetracarboxylic dianhydride?PTCDA?/gold electrode?Au?was manufactured by vacuum thermal evaporation method.Utilizing the complementarity of the absorption spectra of p-Si,CuPc and PTCDA,a broad spectral response from ultraviolet light to near-infrared light is realized.Under the effect of the hole blocking layer C₆₀,the dark current of the device is reduced.When the thickness of the C₆₀ layer is 10 nm,the dark current of the device is reduced to 25.6?A,and the specific detectivity is optimal,exceeding 10¹¹ Jones in the wavelength range of405nm⁶55nm.?2?The manufacture of polyvinylpyrrolidone?PVP?modified perovskite?CH₃NH₃PbI₃?films was completed by the one-step solution method.Then a broad spectral photodiode based on p-Si/PVP modified perovskite/C₆₀/Au structure was manufactured.Utilizing the complementarity of the absorption spectra of p-Si and perovskite,a broad spectral response from ultraviolet light to near-infrared light is realized.Under the effect of the hole blocking layer C₆₀,the device dark current is reduced.When the thickness of the C₆₀ layer is 10 nm,the dark current is reduced to1.4?A,and the specific detectivity in the wavelength range of 405 nm⁸08 nm reaches10¹¹ Jones.