Clarifying the Photonic, Electronic, and Acoustic Characteristics of Quantum-sized Silicon for Functional Integration

研究了量子尺寸硅的光子、电子和声学特性及其在功能集成器件中的应用。研究结果及意义总结如下：(1)基于增强发光的光子器件的发展——通过退火和表面钝化相结合的方法，大大提高了器件的效率和稳定性，然后通过光激发-弛豫过程的分析，明确了纳米硅中能量转移的证据。——开发了稳定蓝光、光腔、光导、纳米线、三维周期纳米结构等硅光子学组成部分的工艺技术。(2)弹道电子发射器的应用——纳米硅弹道电子发射器作为负离子源和氢气产生手段的有效性分别在空气和纯水中得到了证明。-在真空中的适用性也被用作平行电子束光刻和超高灵敏度图像传感的平面冷阴极。(3)改进超声发射和器件应用——在系统分析的基础上，开发了与纳米硅器件高效稳定的超声发射兼容的合适设计和驱动技术。-由于频率响应平坦，纳米硅发射极成功地应用于生物声学通信和数字信息传输的声源研究。(4)功能集成的实现-给出了将光子、电子和声学功能单片集成到硅衬底上的器件概念和工艺流程。通过两种器件的原型设计：声发射电致发光二极管和具有弹道激励机制的表面发射器件，证明了该方法的可行性。

Photonic, electronic, and acoustic properties of quantum-sized silicon have been studied for their characterizations and device applications toward the functional integration. The results and significances are summarized as follows.(1) Development of photonic devices based on enhanced luminescence- It was confirmed by combination of anneal with surface passivation that both the efficiency and the stability were much improved, and then the evidence of energy transfer in nanosilicon was clearly detected by analyses of photoexcitation-relaxation process.- Process technologies for stable blue luminescence, optical cavity, photoconduction, nanowire, and 3-dimensional periodic nanostructure were developed as components of silicon photonics.(2) Applications of ballistic electron emitter- The usefulness of nanosilicon ballistic electron emitter as means of negative ion source and hydrogen gas generation was shown by operation in air and in pure water, respectively.- The applicability in vacuum was also demonstrated by the use as planar cold cathode for parallel electron-beam lithography and ultra-high-sensitivity image sensing.(3) Improved ultrasonic emission and device applications- The appropriate design and driving techniques compatible with efficient and stable ultrasonic emission from nanosilicon device were developed on a basis of systematic analyses.- Due to the flat frequency response, the nanosilicon emitter was successfully applied to sound source for studies on bio-acoustic communication and digital information transmission.(4) Implementation of functional integration- The device concept and process flow were given for monolithic integration of photonic, electronic, and acoustic functions into silicon substrate.- Actuality of this approach was demonstrated by prototyping two devices : sound-emissive electroluminescent diode and surface-emitting device with ballistic excitation mechanism.