NER/SNB: Nanophononics: A New Approach to Electron Transport Enhancement in Nanoscale Devices

本研究的目的是证明在特殊设计的声学不匹配纳米结构中，限制电子-限制声子散射率抑制和相应的电子迁移率增强的可能性。这种新型纳米声子方法是基于嵌入在具有较小声阻抗Z（材料质量密度和声速的乘积）的屏障材料中的半导体纳米线中的声子耗尽/积累效应。研究重点是对嵌入在“声软”包层中的半导体通道中的电子迁移率和电导率进行严格计算；选择最佳的纳米线和阻挡材料参数，最大限度地提高迁移率；以及使用原型结构的概念验证实验演示。该研究将对电子行业产生强烈的影响，影响传统的互补金属氧化物半导体（CMOS）技术和超越CMOS的电子器件设计。该研究将增加纳米结构和纳米器件中电子传递的核心知识，并将有助于发展声子工程的概念。所设想的声子工程（纳米声子）方法对电子设备操作的增强可能具有与电子带隙工程相当的影响，这给电子和光电子工业带来了一场革命。该项目开发的方法将被转移到半导体行业。此外，这项跨学科研究将有助于在加州大学河滨分校建立一个强大的纳米技术教育计划，这是一所少数民族服务机构，在加州大学所有10个校区中，少数民族学生人数最多。

The objective of this research is to demonstrate a possibility of the confined electron - confined phonon scattering rate suppression and corresponding enhancement of the electron mobility in the specially designed acoustically mismatched nanostructures. The novel nanophononic approach is based on the phonon depletion/accumulation effect in the semiconductor nanowires embedded within a barrier material characterized by a smaller acoustic impedance Z (which is a product of the material mass density and the sound velocity). The research is focused on the rigorous calculation of the electron mobility and electrical conductivity in the semiconductor channel embedded into the "acoustically softer" cladding layer; selection of the optimum nanowire and barrier material parameters for the maximum mobility enhancement; and experimental proof-of-the-concept demonstration using the prototype structures. The research will have a strong impact on the electronic industry affecting both the conventional complementary metal-oxide-semiconductor (CMOS) technology and beyond-CMOS electronic device designs. The research will add to the core knowledge of the electron transport in nanostructures and nanodevices, and will help to develop the concept of phonon engineering. The envisioned phonon engineering (nanophononics) approach to the enhancement of the electronic device operation may have an impact comparable to that of the electron band-gap engineering, which brought a revolution to the electronic and optoelectronic industries. The methods developed under this project will be transferred to semiconductor industry. In addition, this interdisciplinary research will help in building a strong nanotechnology educational program in UC-Riverside, the minority serving institution, with the largest minority student population of all 10 University of California campuses.