Preparation Of InP And InAsP Semiconductor Nanowires And Research On Their Optoelectronic Devices

Ⅲ-Ⅴ group semiconductor nanowires have extremely high electron mobility and tremendous potential applications in the field of near-infrared optoelectronics.Traditional chemical vapor deposition(CVD)synthesized nanowires lack flexibility in controlling the V/III ratio and generally have lower crystal quality.In this study,high crystal quality In P and InAsP semiconductor nanowires were synthesized using a novel CVD system.The morphology and structure of the material were characterized by scanning electron microscopy(SEM),X-ray diffractometer(XRD)and scanning transmission electron microscopy(TEM),and the characterization results showed that the grown nanowire material had high crystallinity and excellent crystal quality,This is due to the flexibility to control the V/III beam ratio by adding the appropriate amount of P source to the CVD system in the dual-temperature zone.The optical properties of the materials were characterized using an infrared low-temperature PL test system and a confocal Raman spectrometer with an In Ga As detector.The photoelectric response characteristics of In P nanowire devices were tested by semiconductor analyzer and power tunable laser system(Xenon lamp),and the light-to-dark current ratio of the device reached 6.2,which was excellent in this field.The transistor characteristics of InAsP nanowire devices were tested using a semiconductor analyzer.The main work and innovations of this study are as follows:1、For the first time,a new CVD growth method was used to prepare high crystal quality In P nanowires by improving and optimizing the growth process: adding more P sources to the CVD system in the dual temperature zone,better controlling the V/III beam ratio.Compared with In P nanowires grown by traditional CVD growth methods(as characterized by SEM results),it was confirmed that the nanowires synthesized by this novel CVD growth method had a superior morphology.TEM characterization results showed that the electron diffraction spots were arranged in an orderly manner without twinning,further indicating that In P nanowires have excellent single-crystal structure and crystal quality,and also proving the feasibility of this new CVD method.2、For the first time,Ti/Au and Cr/Au were used as the electrode materials for In P nanowire photodetectors in a comparative experiment.By testing the I-V characteristic curve under adjustable power laser system illumination and comparing the results,it was demonstrated that Ti/Au had superior optical and contact properties as the electrode material for In P nanowire photodetectors,and the light-dark current ratio of the detector reached 6.2.3、InAsP nanowires were synthesized using the new CVD growth method,and their morphology and structure were characterized by SEM and TEM.The transfer characteristic and output characteristic curves of the transistor devices prepared with InAsP nanowires were tested.The results showed that the InAsP nanowire devices exhibited good transistor characteristics.