摘要
为了构筑光传感和阻变一体化光电器件,利用脉冲激光沉积法制备兼具稳定自驱动光响应和电致阻变特性的Pt/Ga_(2)O_(3)/Nb:Sr TiO_(3)光电器件,研究了器件的光响应机制与阻变机理。在0 V偏压下,器件具有快速的紫外光响应特性(τr/τd=60 ms/120 ms),峰值光响应度达13.4 mA/W(λ=250 nm)。上述自驱动光响应被归因于Pt/Ga_(2)O_(3)界面形成的Schottky结内建电场对光生载流子的高效分离作用。同时,器件呈现稳定的双极性阻变行为,高/低阻值变换比约为104,通过施加不同的脉冲电压可实现多阻态间的快速切换,且具有良好的抗疲劳和保持特性。器件的多级阻变效应主要来源于载流子注入和氧空位陷阱中心束缚/解束缚对Schottky势垒的调控作用。以上研究对于开发新型Ga_(2)O_(3)基多功能光电器件具有指导意义。
Introduction Ga_(2)O_(3) is an ultra-wide bandgap semiconductor,which has a direct bandgap of 4.9 eV.Also,it has the superior thermodynamic and chemical stability,making it suitable for the development of deep ultraviolet optoelectronic devices.Ga_(2)O_(3)exhibits the superior photosensitive and resistive properties,which has a promising application in sensor-memory integrated optoelectronic devices.In this paper,the crystal structure,composition,and morphology of the Ga_(2)O_(3) thin film grown via pulsed laser deposition(PLD)was discussed,and then an optoelectronic device with Pt/Ga_(2)O_(3)/NSTO/In structure was designed and constructed.The physical mechanism of the Ga_(2)O_(3)-based device was investigated.The device process was optimized to achieve both high sensitivity ultraviolet photo-response and stable resistive switching characteristics.This work can provide theoretical guidance and technical support for the development of novel Ga_(2)O_(3)-based multifunctional optoelectronic devices.Methods Ga_(2)O_(3) thin films were grown on(100)Nd:SrTiO_(3)(NSTO)substrates by the PLD method.The target material used was a pure Ga_(2)O_(3) ceramic target prepared by a solid-state method.Before thin film deposition,the ceramic target was pre-ablated for 3 min to remove surface contaminants.The film deposition was performed at pulse laser energy of 300 mJ,O_(2) partial pressure of 3.0 Pa,and substrate temperature of 650℃.The target rotation speed was 5 r/min,the substrate rotation speed was 10 r/min,the pulse laser frequency was 5 Hz,and the deposition time was 30 min.Based on the deposited Ga_(2)O_(3) thin films,a device with metal/Ga_(2)O_(3)/electrode sandwich structure was further constructed.At room temperature,Pt metal dot electrodes were fabricated on the surface of Ga_(2)O_(3) thin films by a DC magnetron sputtering method as a top electrode of the device,and then weld the metal indium(In)directly onto the back of the NSTO substrate as a bottom contact electrode.The above Pt metal electrode preparation proce
作者
张腾
张源
任达华
李强
余基映
周金能
易金桥
ZHANG Teng;ZHANG Yuan;REN Dahua;LI Qiang;YU Jiying;ZHOU Jinneng;YI Jinqiao(College of Intelligent Systems Science and Engineering,Hubei Minzu University,Enshi 445000,Hubei,China;HuaXinTechnology(Enshi)Co.,Ltd.,Enshi 445000,Hubei,China)
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2024年第1期161-169,共9页
Journal of The Chinese Ceramic Society
基金
湖北省自然科学基金(2022CFB758)
湖北省教育厅青年人才项目(Q20211906)
湖北民族大学青年科研项目(MY2018Q020)
恩施州青年人才项目(D20220066)
国家自然科学基金(11964009)。
关键词
宽禁带半导体
氧化镓薄膜
紫外光响应
电致阻变效应
wide-bandgap semiconductors
gallium oxide thin film
ultra-violet photoresponse
resistive switching effect
