Surface and Overlayer Electronic Structure of Wide Band Gap Nitride Semiconductors

这一个人研究人员奖授予波士顿大学的一位年轻教授，以表彰他研究宽带隙氮化物半导体的基本表面电子结构以及这种氮化物上金属和非金属覆盖层的电子结构的项目。该计划的具体目标是首先研究氮化物合金的表面电子结构；然后研究简单气体分子在具有良好特性的氮化物表面上的吸附，以了解它们的化学反应、钝化和非金属覆盖层的性质；最后研究金属与氮化物的反应，目的是了解接触覆盖层的生长、结构和稳定性。电子结构将用两种互补的光谱仪测量：角分辨光电子能谱和逆光电子能谱。这种光谱技术的结合将提供对宽带隙氮化物半导体表面电子和化学性质的全面了解。该项目将教育博士后研究助理、研究生和本科生有关新型半导体材料的物理学，以及最先进的光谱探头在他们的研究中的应用。%是一种重要的基于氮化物的新型半导体，由于其在激光和其他在蓝/紫外光部分工作的光学器件中的许多潜在应用，因此成为密切关注的焦点。这些材料被称为宽带隙氮化物半导体，也有望用于温度比传统材料高得多的电子设备。虽然已经用这些氮化物制造了许多简单的器件，但对它们的表面性质仍然严重缺乏了解。了解这些新半导体的基本表面性质对于这些新半导体的充分商业开发至关重要，因为表面电子结构控制着它们的化学反应能力、结构稳定性以及其他材料如何与氮化物结合形成电接触等许多方面。授予波士顿大学一位年轻教授的个人研究人员奖是为了表彰一个项目，该项目使用两种探测器：光电子能谱和逆光电子能谱来研究这些半导体的表面性质。这些探测器分别涉及用强x射线照射材料中的电子并测量其响应，或将电子插入固体中并测量发射的x射线。这种光谱的组合将提供对宽带隙氮化物半导体表面电子和化学性质的全面了解。该计划还将教育博士后研究助理、研究生和本科生有关新型半导体材料的物理学，以及最先进的光谱探测器在他们的研究中的应用。

This individual investigator award is to a young professor at Boston University for a project to study both the basic surface electronic structure of wide band gap nitride semiconductors, and the electronic structure of metal and non-metal overlayers on such nitrides. The specific goals of the program are to first study the surface electronic structure of nitride alloys; then to study the adsorption of simple gas molecules on well characterized nitride surfaces in order to understand their chemical reactivity, passivation, and properties of non-metal overlayers; and finally to study the reaction of metals with nitrides with the aim of understanding the growth, structure, and stability of contact overlayers. The electronic structure will be measured using two complimentary spectroscopies: angle resolved photoemission and inverse photoemission. This combination of spectroscopic techniques will provide a comprehensive understanding of the surface electronic and chemical properties of wide band gap nitride semiconductors. The project will educate postdoctoral research associates, graduate and undergraduate students in the physics of novel semiconductor materials, and the application of state of the art spectroscopic probes in their study. %%%An important new class of semiconductor based on nitrogen compounds is the focus of intense scrutiny due to their numerous potential applications in lasers and other optical devices that operate in the blue/UV portion of the spectrum. These materials, known as wide band gap nitride semiconductors, also hold the promise of being used in electronic devices operating at much higher temperatures than conventional materials. While many simple devices have been fabricated from these nitrides, there remains an acute lack of knowledge about their surface properties. It is of vital importance for the full commercial exploitation of these new semiconductors to understand their basic surface properties since the surface electronic structure controls many aspects of their chemical reactivity, their structural stability, and how other materials are bonded to the nitrides to form, for example, electrical contacts. This individual investigator award to a young professor at Boston University is for a project to study surface properties of these semiconductors using two probes: photoemission spectroscopy and inverse photoemission spectroscopy. These probes involve respectively the excitation of the electrons in the material by illumination with intense x-rays and measuring their response, or inserting electrons into the solid, and measuring emitted x-rays. This combination of spectroscopies will provide a comprehensive understanding of the surface electronic and chemical properties of wide band gap nitride semiconductors. The program will also educate postdoctoral research associates, graduate and undergraduate students in the physics of novel semiconductor materials, and the application of state of the art spectroscopic probes in their study.***