宽带隙功率微波器件陷阱与缺陷原位表征技术及相关退化机理研究

Due to the excellent performance of wide bandgap devices in high frequency, high power applications and harsh environments, GaN and SiC-based power devices have become the next generation of key components for defense, communications, power electronics and other applications. At present, the degradation of devices' electrical parameters and their reliability problems have become the focus when devices are put into the application. In particular, defects and traps in the active area of ​​the wideband device are the key factors that affect the stability and reliability. The traditional defect and trap characterization method can not be applied to the actual device because of its very small size. To solve this problem, we proposed to implement the RC network and Bayesian iteration by collecting the transient current of the device in this project. Through the one-year funding of National Natural Science Foundation in 2016, the research has realized the breakthrough of “peak spectroscopy" in charactering defects and traps in GaN HEMT devices. In this project, we will further optimize and improve the trap "peak spectroscopy" device characterization technology, and extend to the wide bandgap device qualitatively and quantitatively; We will study the mechanism of failure mechanism and the relationship between internal mechanism and parameter degradation by monitoring the variety of characteristic lines. Also, we will explore the way to improve the reliability of the device and solve the key problem of optimizing the wide band gap power microwave device.

由于宽带隙器件在高频、大功率应用及恶劣环境下的出色表现，GaN、SiC基器件已经成为国防、通信、电力电子等应用领域期盼的下一代关键元器件。目前，器件应用后其性能参数随时间退化-器件可靠性物理问题已经成为关注的重点，其中宽带隙器件有源区存在的缺陷与陷阱是影响稳定性与可靠性的关键因素。本项目针对传统缺陷与陷阱表征方法不能适用于实际器件原位测量技术的限制，拟通过采集器件瞬态电流变化，并对其实施RC网络和贝叶斯迭代处理，经2016年一年期主任基金的研究，实现了GaN HEMT器件中缺陷和陷阱的“峰值谱”研究突破。本项目中，将进一步优化、完善陷阱的“峰值谱”器件原位表征技术，并扩展至宽带隙器件缺陷和陷阱的定性及定量表征能力提升研究；利用特征谱线随时间的变化，研究器件失效退化机理，建立内在机理与参数退化的关系模型；探索提高器件可靠性的措施，解决宽带隙功率微波器件性能优化设计的关键问题。

GaN、SiC基器件因其较大的禁带宽度而在高频、大功率领域内有着良好的应用前景，其已成为国防、通信、电力电子等军用和民用领域的关键核心元器件。然而，器件应用后其性能参数随时间退化-器件可靠性物理问题已经成为关注的重点，其中宽带隙器件有源区存在的缺陷与陷阱是影响稳定性与可靠性的关键因素。本项目在为期一年的研究时间里通过优化传统采集电路，提出了一种采集电压模式的瞬态电学法，其可以避免传统瞬态电流法中存在的电压漂移现象；同时，我们将该方法应用于实际器件测试中，表征了陷阱效应及其对其他器件特性的影响程度；我们研究了高能粒子对器件电学特性的影响，尤其是陷阱的影响，并进行了相关比对实验。这一优化的测试方法和研究数据对今后进一步提升HEMT器件陷阱效应的研究提供了重要支撑。