Cu、Sn掺杂的沟道型β-Ga₂O₃半导体薄膜光电器件的制备及特性研究
Preparation and Characterization of Channeled β-Ga₂O₃ Semiconductor Thin Film Optoelectronic Devices Doped with Cu and Sn Elements

本文利用双靶射频磁控溅射技术，在不同实验条件下，开展了本征β-Ga₂O₃和Cu、Sn掺杂的沟道型β-Ga₂O₃半导体薄膜光电器件的制备及特性研究工作。分析了掺杂前后制备的二维β-Ga₂O₃薄膜的微结构、表面形貌及化学成份。比较了不同条件下制备器件的电导率、IV特性及光电特性。研究发现，Cu、Sn掺杂后，β-Ga₂O₃半导体薄膜光电器件的电导率、IV特性和光电特性都有一定的改善，而Sn掺杂的Sn/β-Ga₂O₃薄膜的电导率增加幅度最大。其中，Sn/β-Ga₂O₃器件呈现了最佳IV特性，说明Sn掺杂比Cu掺杂的效果更好。同时，掺杂并进行退火处理更可使薄膜的电导率呈现数量级的提升。制备的不同二维沟道型器件都具有明显的场效应器件特征，可用外加底栅电压VGS调控器件的源漏电流IGS。在254 nm的紫外光源辐照下，所有器件都出现了明显的光电流。但掺杂后器件的光电流明显高于本征器件的光电流，Sn掺杂Sn/β-Ga₂O₃器件的光电流最大，响应时间最短，光电流与暗电流之比可达112，器件具有更好的稳定性和可逆性。
In this work, the channeled intrinsic, Cu- and Sn-doped β-Ga₂O₃ semiconductor thin film optoelectronic devices were fabricated under different experi-mental conditions by double target RF magnetron sputtering technology. The characteristics of the prepared β-Ga2O3 thin films and optoelectronic devices before and after doping were systematically investigated, including the microstructure, surface morphology, chemical composition of the 2D β-Ga₂O₃ thin films as well as the photo-electric properties of the devices. It was found that the per-formances of the Cu- and Sn-doped channeled β-Ga₂O₃ optoelectronic devices were significantly im-proved, such as the conductivity, IV and photoelectric characteristic. Especially, the conductivity of Sn-doped β-Ga₂O₃ thin films showed the largest increase and exhibited a typical IV characteristic, which indicates that the properties of β-Ga₂O₃ films can be improved by Sn-doping compared to Cu doping. Moreover, doping and annealing methods can increase the conductivity of the β-Ga₂O₃ thin films by orders of magnitude. The results showed that the different two-dimensional channeled op-toelectronic devices have an obvious field effect device characteristic, and the IGS of the optoelec-tronic devices can be controlled by the back gate voltage. All of the as-prepared devices have a good response to the ultraviolet (UV)