Investigation of Factors Affecting the Performance of Electrical Contacts to Gallium Nitride

小行星9504259 这项研究计划资助的重点是研究，以了解基本材料科学方面的热稳定电接触到第三族氮化物，主要是氮化镓（GaN）。 热力学计算将被使用，沿着与X射线衍射和电子探针显微分析的体相平衡样品，以确定在金属-Ga-N系统的固相图的关键特征。 这项研究将有助于热稳定接触材料的选择。 此外，由于GaN上的N2的高蒸气压和N空位对GaN中的载流子浓度的假定作用，预计气相平衡对GaN接触的热稳定性和电性能的影响比它们对其他III-V族半导体接触的影响更大。 控制GaN点缺陷浓度和接触/GaN势垒高度的新颖和常规方法将被评估其潜在的工程师的电性能的那些接触，已经从热稳定性的观点有吸引力。 这些方法将包括试图操纵接触/GaN界面正下方的N空位浓度以影响n型载流子浓度。 还将评估接触材料的功函数对势垒高度和接触的后续性能的作用。 虽然该项目将主要集中在氮化镓的电接触的开发上，但它也将有利于未来其他III族氮化物的接触设计，并将有助于更好地理解这些半导体的材料问题。 在项目规划期间，将选择至少两个模型系统来测试控制氮化镓触点的电气性能和稳定性的想法。 计划期将帮助PI完成足够的初步工作，以显示想法的前景或根据所获得的数据对其进行修改。因此，规划期间的支持将有助于PI准备更具竞争力的完整提案。 ***

9504259 Mohney This Research Planning Grant focuses on studies to understand fundamental materials science aspects of thermally stable electrical contacts to group III nitrides, primarily Gallium Nitride (GaN). Thermodynamic calculations will be used, along with x-ray diffraction and electron probe microanalysis of bulk phase equilibria samples, to determine key features of the solid phase diagrams in the Metal-Ga-N systems. This investigation will aid in the selection of thermally stable contact materials. In addition, because of the high vapor pressure of N2 over GaN and the presumed role of N vacancies on the carrier concentration in GaN, the gas phase equilibria are expected to exert a greater influence on the thermal stability and electrical properties of contacts to GaN than they do for contacts to the other III-V semiconductors. Both novel and conventional methods to control the GaN point defect concentration and the contact/GaN barrier height will then be evaluated for their potential to engineer the electrical properties of those contacts that are already attractive from the standpoint of thermal stability. These methods will include attempts to manipulate the N vacancy concentration immediately beneath the contact/GaN interface to influence the n-type carrier concentration. The role of the work function of the contact material on the barrier height and subsequent performance of the contact will also be evaluated. %%% While this project will focus primarily on the development of electrical contacts to Gallium Nitride, it will also be of benefit for future design of contacts to other group III nitrides, and will contribute to a greater understanding of materials issues for these semiconductors. During the planning period of the project, at least two model systems will be selected to test ideas for controlling the electrical properties and stability of contacts to Gallium Nitride. The planning period will aid the PI in accomplishing enough prelimin ary work to show the promise of ideas or to modify them based on the data acquired. Thus, support during the planning period will aid the PI in preparing a more competitive full proposal. ***