無触媒窒化物系ナノワイヤの有機金属化合物気相成長と太陽光発電素子応用

本研究的主要目的是研究InGaN/GaN基纳米线太阳能电池的光伏效应。为了生长GaN核心纳米结构，采用了选择性区域生长，从而获得了高纵横比和高质量的GaN纳米线。随后，重点研究了作为光吸收层的InGaN壳层结构的生长。为了表征生长的核壳结构InGaN纳米线的发射特性，采用了多种空间高分辨方法，如透射电子显微镜、化学发光等。根据这些结果，我们已经报道了五篇期刊论文和六次国际会议。这些出版物涵盖了先进的生长技术，以获得高质量的GaN纳米棒，不仅使用MOCVD，而且还使用其他外延工具，如MBE和HVPE。事实上，人们已经进行了广泛的试验，以找到生长均匀的GaN纳米线的合适条件。为了探索在新材料上生长的可行性，人们尝试了几种材料，如蓝宝石、硅和二氧化硅衬底。InGaN壳层的发射特性间接反映了InGaN核壳纳米线的吸收特性。此外，基于实验结果的模拟显示了InGaN核壳纳米线太阳能电池的更大潜力。因此，我们相信，这项研究将在不久的将来对高效纳米线太阳能电池的发展做出真正的贡献。

The main purpose of this research is to study the photovoltaic effect of InGaN/GaN-based nanowire solar cells. To grow GaN core nanostructures, selective area growth was used, thereby resulting in GaN nanowires with high aspect ratio and high quality. Afterwards, the research has been focused on the growth of InGaN shell structures acting as an light absorption layer. To characterize the emission properties of grown core-shell InGaN nanowires, several kinds of spacial high-resolution methods have been used such as TEM and CL. Based-on these results, we have reported five joural papers and six international conferences. These publications cover the advanced growth technology to obtain high quality of GaN nanorods not only with MOCVD but also with other epitaxy tools such as MBE and HVPE. Indeed, extensive trials have been made to find the appropriate growth condition for growing uniform GaN nanowire. To find the feasiblity of the growth on novel materials, several kinds of substancs were attempted such as sapphire, silicon, and silica substrates. The emission characteristics of InGaN shells indirectly reflected the absorption properties of InGaN core-shell nanowires. Furthermore, a simulation based on the experimental resutls showed more promise potential of InGaN core-shell nanowwire solar cells. Thus, we believe that this study will really contribute to the development of high effiecicy nanowire solar cell in the near future.