Design And Characterization Of The Semiconductor Nanowires/Microwires Device

Semiconductor materials(such as CdS,Zn O,Ga N,etc.),which have wide direct band gap,all have their own excellent photoelectric performance.Besides,their wurtzite crystal structure lead them to unique piezoelectric properties.As the semiconductor optoelectronic devices become more and more miniaturization,micro-/nano-devices,based on those materials,have attracted more attention.These materials can be used to make several devices,such as FET,LED,Optical pumped lasers,Electrical pumped lasers,Photodetector,etc.Those devices have been extensively investigated both at home and abroad.In this paper,CdS nanoribbon,Ga N microwire,and Ga N nanowire are prepared by chemical vapor deposition.We have grown the patterned Zn O nanowires by hydrothermal.The main contents of this paper are listed as following:1.CdS nanoribbon,Ga N nanowire,and Ga N microwire have been synthesized by chemical vapor deposition(CVD).We have analyzed their growth mechanism.In addition,combining with the lithography and hydrothermal,we have obtained the patterned Zn O nanowires array at the ITO substrate,and have grown the Zn O microwire array at the N-Ga N substrate.The structural and optical properties of those obtained materials are characterized by SEM,XRD,PL,etc.2.The optical excitation of CdS nanoribbons and Ga N microwires are studied.CdS nanoribbons have a FP mode cavity,which have a excitation threshold of about70 k W/cm2.With the increase of the cavity length,the laser peaks of CdS nanoribbons have a clearly red shift.Ga N microwires have a WGM mode cavity and possess a excitation threshold of about 280 k W/cm2.We have fabricated the N-Ga N microwire/P-Ga N homojunction LED,and their electroluminescence spectrum is investigated.3.The OLED devices based on the Zn O nanowires array is prepared,which can be flexible and controllable by using ITO/PET substrate.The devices have a broad variation spatial resolution,from 3?m to 20?m,which can be controlled by the pattern of the Zn O nanowires array.The light emission of blue,red,and green can be achieved by depositing different organic materials.Combined with piezo-phototronic effect,the light emission can be enhanced under the static pressure.Under the appliedpressure of 100 MPa,the fluorescence intensity of the device can reach 1100% higher than the original.This device will find applications in many fields,such as electronic skins,biomedical science,etc.