Fabrication of ErSiO self-organized superlattice thin films and evaluation of the 1.54μm optical waveguide amplification characteristics

本论文主要研究自组织超晶格结构的ErSiO新材料及其在1.54μm光波导放大器中的应用。2003年，我们采用MOMBE、纳米多孔硅和溶胶-凝胶法制备了ErSiO新薄膜。各种方法都可以成功地形成ErSiO晶体材料。在室温下，由于Er 4f-4f跃迁中的Stark分裂，它们都具有ErSiO超晶格的晶体结构特征，并且具有尖锐而精细的1.54μm发光光谱。利用这些改进的ErSiO薄膜，研究了ErSiO超晶格的自组织机制、详细的晶体结构、电学性质以及ErSiO薄膜独特的发光光谱和短的荧光寿命的原因。第一，控制 ...更多信息 Er：Si：O = 1：2：2.4时，特别是控制O的含量对ErSiO晶体超晶格的生长至关重要，ErSiO晶体具有独特的发光光谱和快速的荧光寿命。本文还尝试了激光烧蚀法，结合溶胶-凝胶法和MOMBE法的工艺改进，在较低的工艺温度下获得改进的ErSiO超晶格。在900-1000℃下获得了ErSiO晶体薄膜，比以前降低了约200℃。在2005财政年度，详细研究了非常快的荧光寿命的起源，10-20μs，而在掺铒的Si相关材料中的几个ms。通过改变ErSiO薄膜中的光密度，发现快荧光寿命是ErSiO本身的辐射寿命，这可能是由于Er^3+离子上非常均匀和强的晶场所致。研究了ErSiO光波导的传输特性和上转换特性，结果表明，Er浓度大于10^<20>/cm ^3，辐射寿命为10-20μs的ErSiO是一种很有前途的1.54μm受激发射和光放大材料。少

This study deals with the ErSiO new materials with a self-organized superlattice structure and its possibility for the 1.54μm optical waveguide amplification.In the fiscal year 2003, fabrication of ErSiO new thin films were developed using MOMBE, nano-structured porous silicon and sol-gel methods. ErSiO crystalline materials could be successfully formed by every method. They all show crystalline structures characteristics of ErSiO superlattice and also sharp and fine-structured 1.54μm luminescence spectra at room temperature due to Stark splittings in the Er 4f-4f transitions.In the fiscal year 2004, developments of a new fabrication method and the process improvements for ErSiO films thicker than 100 nm were studied. Using these improved ErSiO thin films, the self-organization mechanisms of ErSiO superlattice, detailed crystalline structures, electrical properties, and the origins of the peculiar luminescence spectra and the short fluorescence lifetime were investigated. First, contro … More l of the ratio of Er, Si and O at 1:2:2.4, especially control of O, was found to be most important for the growth of ErSiO crystalline superlattices with their peculiar luminescence spectra and fast fluorescence lifetime. A laser ablation method was also attempted to obtained improved ErSiO superlattice at lower process temperature together with process improvements of sol-gel and MOMBE methods. ErSiO crystalline thin films were obtained at 900-1000℃, about 200℃ lower than before. Possibility of epitaxial growth on tilted Si(100) by MOMBE was shown.In the fiscal year 2005, origins of very fast fluorescence lifetimes, 10-20μs compared to several ms in Er-doped Si-related materials, were studied in detail. By varying the optical density in ErSiO thin films, it was found that the fast fluorescence lifetime was the radiative lifetime itself of ErSiO, which may be due to very uniform and strong crystalline fields on Er^<3+> ions. ErSiO optical waveguides were formed and the transmission properties and up-conversion characteristics were studied.In conclusion, ErSiO with the Er concentration higher than 10^<20>/cm^3 and the radiative lifetime of 10-20μs is a very promising materials for the stimulated emission and light amplification at 1.54μm. Less