GaN电力电子器件钝化关键技术研究

项目名称： GaN电力电子器件钝化关键技术研究

项目编号： No.61306100

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 无线电电子学、电信技术

项目作者： 董志华

作者单位： 杭州电子科技大学

项目金额： 25万元

中文摘要： 增强型AlGaN/GaN HEMT电力电子器件因其优异性能越来越引起人们的注意。然而器件本身存在的阈值"回滞"和由于电力电子高压应用环境所导致的比微波功率器件更加棘手的"电流崩塌"严重影响了器件实用化的进度。这两个问题都可以归结为：如何提高钝化介质与衬底界面质量，减少界面态的问题。针对这一目的，本项目利用利用高频C-V结合准静态C-V测试方式，深入研究界面态的性质，并结合剖面形貌分析寻找造成界面态的机理，并提出改进钝化效果的技术方案。利用独创的直流脉冲测试方法分析器件的"电流崩塌"机制,并提出改进的钝化方案。最终，实现无阈值"回滞"和"电流崩塌"的电力电子器件。

中文关键词： AlGaN/GaN HEMT；阈值回滞；电流崩塌；表面处理；钝化

英文摘要： Normally-off AlGaN/GaN HEMT for power switching applications was concerned more and more because its outstanding performances. Unfortunately, the hysteresis in threshold voltage and current collapse, which is even more troublesome than that in microwave power devices, impeded its step for being widely applied. The two above problems can be attributed to how to get better quality of interface between passivation insulator and AlGaN/GaN and reduce the interface states. To solve this, in this project, we would design and fabricate different MIS-HEMTs and testing structures and measured with high quency C-V and quasi-static C-V measurements to analyze the property of the interfaces. Furthermore, the mechanism of the interface states would be research through the profile observation of the testing structures. The technique for improving the passivation would be brought out based on the analysis. The original methods of pulsed DC measurement would be applied to analyze current collapse. Improved passivation technologies would be brought out based on the analysis. Finally, the optimized passivation technology would be combined to obtain hysteresis and current collapse free HEMT for power switching applications.

英文关键词： AlGaN/GaN HEMT；threshold-voltage hysteresis；current collapse；surface treatment；passivation