Analysis On The Characteristics Of GaN Based Two-dimensional Semiconductor Materials Photodetector

In recent years,the preparation of high-performance optoelectronic devices using two-dimensional semiconductor materials has become a hot research direction.PtSe₂is one of the materials in two-dimensional semiconductors.When PtSe₂is used as the channel material for field-effect transistors,the size of FET devices can be reduced,the dielectric constant can be increased,and the carrier mobility can be accelerated.The photoelectric performance of FET has been significantly improved.In addition,combining PtSe₂in the infrared band with broadband gap semiconductor materials in the ultraviolet band can produce heterojunction photodetectors.Their material characteristics can complement each other,broaden the spectral absorption range of devices,and improve the application performance of photodetectors.Nowadays,although there are many achievements related to the preparation of Field-effect transistor and photodetector using two-dimensional semiconductor materials,there are few reports on the research of related optoelectronic devices made using PtSe₂and GaN materials.The foundation of this thesis is the preparation of PtSe₂thin film,and the main research direction is the application of two-dimensional semiconductor materials in FET and GaN based photodetector.Based on the study of FETs with different PtSe₂film thicknesses,the detection ability of photodetector made from PtSe₂films and GaN based materials over a wide spectral range was studied.The following research work was carried out:（1）Using TAC method to produce high-quality PtSe₂thin films and 4×4 array PtSe₂-FET.Characterize and test the PtSe₂thin film and devices produced to investigate the effect of PtSe₂thin film thickness on photoelectric detection performance.Growth of PtSe₂thin films with different thicknesses using TAC method and fabrication of 4×4 array PtSe₂FET.After a series of characterization and testing,it was proven that PtSe₂-FET has good responsiveness in the visible infrared band.Moreover,PtSe₂-FET device with thin PtSe₂thin films exhibit excellent optical response performance.The prepared 4×4 array PtSe₂-FET can detect a wide range of visible to far infrared wavelength.（2）PtSe₂/GaN photodetector can be produced using MOCVD and TAC methods.Characterize and test the grown materials and fabricated devices,and study the detection performance of photodetector in wide spectral bands.Combining wide bandgap GaN with 2D-PtSe₂can help improve the light absorption rate and detection ability of GaN based photodetectors over a wide spectral range.N-GaN and P-GaN epitaxy are grown by using the MOCVD method.PtSe₂/GaN heterojunction photodetector is prepared by using TAC method on GaN substrate.A series of characterization and optoelectronic performance tests is conducted on materials of PtSe₂/GaN heterojunction,PtSe₂/N-GaN,and PtSe₂/P-GaN devices.PtSe₂/GaN photodetector has broad spectral detection and fast light response capabilities in the ultraviolet and infrared bands.Moreover,the PtSe₂/P-GaN photodetector has better response performance in the ultraviolet band.This thesis optimizes the growth quality of array PtSe₂thin films through thermal assisted conversion method.The response sensitivity of the 4×4 array PtSe₂-FET fabricated using this method has been improved in the visible far infrared band.Construct PtSe₂/GaN heterojunction photodetectors on GaN epitaxy prepared by MOCVD method using the same process method.Utilizing the complementary properties of two materials to achieve rapid response of photodetectors in the wide ultraviolet infrared spectral range.This2D/WBS hybrid heterojunction can improve light absorption efficiency and carrier transport efficiency at the interface.This will provide a new direction for the development of two-dimensional semiconductor materials in the field of broadband photodetectors.