Study On Preparation And Properties Of Single NiO Nanowire Devices

One-dimensional semiconductor nanomaterials have excellent electrical and optical properties,which play an important role in the process of constructing integrated circuits and functional components such as nano-electronics and optoelectronic devices.NiO is a direct wide-band gap semiconductor material,due to its special electronic structure and good thermal stability,it has shown excellent application prospects in many fields such as catalyst,photo sensor,gas sensor and so on.In this paper,single NiO nanowire devices have been fabricated by using the traditional integrated circuit processing technology and their performance has been tested.Meanwhile,the process flow of the device has been optimized;the effects of annealing temperature on the I-V and photoelectric properties of single NiO nanowire devices were studied;moreover,the back-gate field effect transistor based on single NiO nanowire was prepared on the Si/SiO₂ substrate and its characteristics were tested and analyzed.The main results are as follows:1.The influence of process parameters on device structure is studied,and the best preparation process is optimized.2.The effects of annealing temperature on the microstructure and I-V properties of single NiO nanowire were studied.It is found that the oxidation degree of nanowires increases with the increase of annealing temperature,and most of the nanowires are Ni/NiO core shell structure;the I-V test shows that the devices are all Schottky structure.In a single NiO nanowire device prepared by annealing at 600?,it is found that the current transmission is a tunneling model when the bias voltage is large;and the current transmission satisfies the image force model in the lower bias range,also the effective barrier of the device decreases gradually with the increase of the applied bias.3.The effects of annealing temperature on the photoelectric properties of single NiO nanowire devices were studied.It is found that the device has good photoelectric response,which annealed at 400?:Under 365nm radiation,at+2V bias,the dark current is about 1.98mA,while the photocurrent is about 8.63mA,the photocurrent is about 4⁵ times as the dark current,and with the increase of bias,photocurrent is increasing gradually;under xenon lamp,the photocurrent increases with illumination intensity;under 248 nm pulse laser,the response time is about 1?s,but the recovery time is about 30?s longer.4.The single NiO nanowire oxidized with 600?was used to fabricate back-gate field effect transistor and the current voltage properties were measured,the results show that the carrier mobility is about 3.2 cm²V^-1s^-1.