Investigation on the physical properties of β-Ga2O3 ultra-violet detectors prepared by atomic layer deposition

• Main Authors: De-Yang Peng, 彭德揚
• Other Authors: Jyh-Rong Gong
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/9a666k

碩士 === 國立中興大學 === 物理學系所 === 106 === In this thesis, β-Ga2O3 thin films were prepared by atomic layer deposition (ALD) deposited at 600oC under atmospheric pressure using triethylgallium (TEGa) and nitrous oxide (N2O) precursors as sources of Ga and O element in β-Ga2O3 thin film. To fabricate a solar-blind photodetector, interdigital Au electrode was deposited on the β-Ga2O3 thin film using shadow mask by magnet sputtering. The physic properties of β-Ga2O3 thin films were characterized using scanning electron microscopy (SEM) and θ-2θ X-ray diffractometer (XRD). The thicknesses of the β-Ga2O3 thin films were measured by cross-sectional SEM images. Based upon the XRD data, it appears that ALD-grown Ga2O3 thin film were β type in nature. The I-V curves of Au-(β-Ga2O3)-Au metal-semiconductor-metal (MSM) structure were measured by Keithley model 2400 source unit. According to the I-V plots, it shows that the dark current of the β-Ga2O3 MSM structure remains approximately 10-9 A. The photo current stays at 4×10-6 A and 1.5×10-3 A by applying a bias of 10V on the β-Ga2O3 MSM structure under 365nm and 254nm UV illumination ,respectively. It is evident that the ALD-grown β-Ga2O3 MSM structure is very sensitive to the 254nm UV illumination. Thus, it is suitable to serve as a solar blind photodetector.