Brillouin spectroscopic studies of porous semiconductor films and related systems

多孔性半导体薄膜是当今最具吸引力和技术前景的材料类别之一，在光子学和生物材料技术等领域具有潜在和已实现的应用。然而，对多孔半导体薄膜特性的探索和表征还处于起步阶段，主要是因为它们的新颖性和能够探测脆弱纳米结构的技术数量有限。特别是，关于弹性波在这些系统中传播的研究很少，弹性性质与其他系统参数之间的关系还没有建立起来。对多孔性半导体弹性性质的了解对器件应用也很重要。例如，有人提出通过改变孔隙率来调节多孔硅的杨氏模数，使其与皮质或松质骨的孔隙率相匹配，从而使其能够用作骨构建支架。我计划在纪念大学从事的研究项目将使用布里渊光谱学来探索多孔性半导体薄膜和相关系统的弹性特性，并与互补的激光光谱学研究相结合，将有助于发现和量化这些特性与这些系统的结构和光学特性之间的关系。这项拟议的研究是我早先通过激光光谱学技术和杠杆在器件制造和材料表征方面获得的专业知识的延伸，这些专业知识是在受雇于北电网络和在纪念大学进行多孔半导体薄膜合成期间获得的。特别令人感兴趣的系统包括多孔硅多层膜、碳纳米管阵列和纳米柱多孔碳化硅薄膜。

Porous semiconductor films are one of today's most fundamentally fascinating and technologically promising materials classes with potential and realized applications in fields such as photonics and biomaterials technology. Exploration and characterization of the properties of porous semiconductor films is, however, in its infancy, due mainly to their novelty and the limited number of techniques capable of probing the fragile nanostructure. In particular, there have been few studies of elastic wave propagation in these systems and the relationships between the elastic properties and other system parameters have yet to be established. Knowledge of the elastic properties of porous semiconductors is also important for device applications. It has been proposed, for example, that Young's modulus of porous Si be tuned by varying the porosity to match that of cortical or cancellous bone thereby enabling its use as a bone-building scaffold. The research program that I plan to pursue at Memorial University will use Brillouin spectroscopy to probe the elastic properties of porous semiconductor films and related systems and, in conjunction with complementary laser spectroscopy studies, will facilitate discovery and quantification of the relationships between these properties and the structural and optical properties of these systems. The proposed research is an extension of my earlier work on porous semiconductors via laser spectroscopy techniques and levers expertise in device fabrication and materials characterization gained during employment with Nortel and in porous semiconductor film synthesis at Memorial University. Systems of particular interest include porous Si multilayers, carbon nanotube arrays and nanocolumnar porous SiC films.