ナノクリスタルドープ光導波路及び次世代フォトニックデバイスへの適用

采用双管同轴线型微波等离子体化学气相沉积(MPCVD)技术制备了纳米硅(nc-Si)薄膜，并研究了不同制备条件对其发光特性的影响。此外，虽然人们认为离子轰击能量与硅纳米晶体的生成有关，但通过分析生成过程，这一点得到了澄清。另一方面，针对一种新型的硅基光子材料，制备了由a-Si：H和Si3N4组成的a-Si：H/Si3N4多层膜，并对其薄膜质量进行了评价。多层膜的光学带隙理论曲线与实验值吻合较好，可以制备出质量较好的多层膜。然后将其加工成平板波导。因此，这种光波导具有TE模切和TM模通的偏振特性。并且随着泵浦光强的增加，消光比增大。为实现高密度、精确位置控制的高质量化合物半导体纳米晶体奠定了基础。用电子束曝光法(EBX)在GaAs衬底上制备了直径为300 nm、深度为2 nm的纳米级凹坑，并用分子束外延(MBE)方法在其上生长了InAs。因此，成功地制备了高度为25 nm的位置控制纳米晶体，并测量了其室温发光。还阐明了堆积结构的可能性。同时，研究了将纳米晶体用于更高器件性能的光子功能器件，实现了多模干涉波长转换器和光子开关的功能，解决了器件应用的根本问题。

We fabricate silicon nano crystal (nc-Si) using Double Tubed Coaxial Line Type Microwave Plasma Chemical Vapor Deposition (MPCVD) and evaluate its photo luminescence characteristics varying fabrication conditions. Furthermore, although it was thought that the ion bombard energy was related to creation of Si nano crystal, this was clarified by analyzing creation process. And we clarify the validity of analysis by calculating the number of Si nano crystals.On the other hand, a new silicons photonic materials is aimed at, we fabricate a-Si : H/Si3N4 multilayer films which consists of a-Si : H and Si_3N_4 and evaluate its film quality. A theoretical curve and an experiment value of optical band gap of multilayer films were agreeing well, and we can fabricate the multilayer films of good quality. And this is processed into slab waveguides. As a result, this waveguides have polarization properties, TE-mode-cut and TM-mode-pass. And when intensity of pumping lights increase, the extinction ratio rises.Fundamental studies for realizing high quality compound semiconductor nanocrystals with which are in high-density and precisely position-controlled have been carried out. Nano-oder dips with 300nm diameter and 2-nm depth were formed on GaAs substrates by using electron beam exposure (EBX) method, and InAs was grown on them by molecular beam epitaxy (MBE) method. As a result, position-controlled nanocrystals of 25nm height with ring shapes associated with those dips were successfully fabricated, and room-temperature PL was measured. Also possibility for stacked structure was clarified. In parallel, photonic functional devices which the nanocrysrtals will be utilized for higher device performances were investigated to have realized foperations of multimode interference wavelength converters and photonic switches, and fundamental issues for the device application were solved.