The growth of GaN nanorods by Plasma-Assisted Molecular Beam Epitaxy and their applications in photovoltaics

• Main Authors: Yang, Chung-Pei, 楊仲培
• Other Authors: Lin, Chun-Ting
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/79211890238957853389

碩士 === 國立交通大學 === 影像與生醫光電研究所 === 103 === In this thesis, the heterostructure GaN nanorods material was grown on Si substrate by Plasma-Assisted Molecular Beam Epitaxy （PA-MBE）and fabricated to solar cells. According to the results of Field Emission Scanning Electron Microscopy（FE-SEM）, we can explain the growth mechanism of GaN nanorods on Si (111). For different growth temperatures and different gallium flow rate, we can also observe various GaN epitaxial processes. By the analysis of FE-SEM and Reflection High Energy Electron Diffraction（RHEED）, we can find the similar trends of surface morphology between the ratio of Ⅴ/Ⅲ from low to high and the growth temperature from low to high. X-ray diffraction shows the substrate temperature increase beneficial to the crystalline of GaN material. From the photoluminescence spectrum, the blue shift phenomenon became more clear for smaller size of GaN nanorods. Reflectivity shows that there will be significant anti-reflective effect at the condition of the growth substrate temperature at 800oC and the lowest gallium flow rate. Finally, we made the samples with different growth parameters into devices, which are deposited Tin oxide（SnO2）as the conductive material, then coated with aluminum and gold electrodes. Solar cells were fabricated in the structure as Al/p-Si/GaN nanorods/SnO2/Au, and were measured their efficiency.