Research On Photoresistive Memory Device Based On Nitrogen-annealed AlO_x Films

Non-volatile memory is one of the most promising devices to replace digital and analog circuits in existing integrated electronic devices,and has the potential to be applied to mimic synaptic structures and neurosynthetic computing.Integrating non-volatile memory devices with photodetector devices to realize the sensing and memorizing processes of optical signals is an important way to mimic the retinal structure and realize the visual memory function.This thesis conducts on the preparation and study of resistive memory devices based on AlO_x films,photodetector devices based on single-layer MoS₂ films,and integrated sensing-storage devices.1.Ni/AlO_x/Au resistive memory devices were fabricated by the coating techniques such as magnetron sputtering and thermal evaporation,and the AlO_x films were treated with nitrogen annealing to enhance their resistive properties.The resistive mechanism of the devices and the effect of nitrogen annealing on the resistive properties were analyzed by various characterization methods.The results show that the nitrogen annealing treatment increases the concentration of oxygen vacancies in the AlO_xfilms,which results in better resistive switching characteristics.The resistive switching characteristics increase with increasing annealing temperature,and 200? is the most suitable temperature.The Ni/AlO_x/Au devices are better than most resistive memory devices based on alumina films because of its Forming-free property,high resistance switching ratio(>10³),long resistance retention time(>10⁴s),and good switching performance(>200).2.Single-layer MoS₂ films were fabricated by CVD and ion intercalation,and MoS₂photodetectors were prepared.The MoS₂ films prepared by CVD have good crystallinity and film formation continuity,but the deposition uniformity is not controllable.The MoS₂films prepared by ion intercalation are uniformly distributed on substrate in the form of monolayer fragments,and their distribution density can be controlled by drop coating process parameters.The photodetector device based on single-layer MoS₂ has a photocurrent of about 10.9?A at 520 nm under green light with the incident power of 50n W and bias voltage of 1V,showing good switching performance under ON/OFF,response and recovery times is 34ms and 23ms respectively.3.A photoresistive memory device based on the above study was designed and initially prepared.The resistive memory part is connected to the photodetection part in series,and the photoreceptor-storage-erase process is realized by the change of resistance state of both.