(Invited) Degradation of SiC Bipolar Devices: A Review of Likely Causes and Recent Advances in its Understanding
(Invited) Degradation of SiC Bipolar Devices: A Review of Likely Causes and Recent Advances in its Understanding
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（特邀）SiC双极器件的退化：可能原因综述及其理解最新进展
DOI：
10.1149/1.3631500
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发表时间：
2011
期刊：
影响因子：
--
通讯作者：
A. Galeckas
中科院分区：
文献类型：
--
作者：
P. Pirouz;A. Galeckas
在上个世纪的最后二十年里，单晶、单多型碳化硅的快速生长，以及在晶体中掺杂施主和受主杂质的能力的快速发展，使碳化硅电子器件的制造成为可能。因此，4H-SiC体迁移率较高，各向异性适中，因此4H-Sc电子器件的研究主要集中在4H-Sc电子器件的制备上。特别是，这对电力设备制造商来说是相当令人兴奋的，因为与硅等传统半导体相比，碳化硅具有更高的阻挡电压，并且可以将其操作能力保持到更高的温度。此外，在较高的电压下，例如~10千伏以上，双极碳化硅器件比单极器件更受欢迎，因为它们具有较低的导通压降。因此，一些大型电气制造商和一些大学的研究实验室开始了开发PIN二极管的广泛研究计划。然而，对这些二极管的可靠性的测试结果令人失望，因为人们发现，即使在环境温度下，4H-SiCPIN二极管在运行时也会迅速退化。这种效应表现为正向电压Vf随操作时间的下降而迅速增加，并且被发现与二极管(2)有源区的本征堆叠故障(ISF)的数量和程度的快速增加有关。这可以在图1中的电致发光(EL)图案中看到，揭示了不同成像的层错和部分位错的光学活性
In the last two decades of last century, rapid advances in the growth of single-crystal, single-polytype SiC, and the ability to controllably dope the crystals with donor and acceptor impurities, made the fabrication of SiC electronic devices a reality. For this purpose, 4H-SiC has certain advantages over other SiC polytypes, such as higher bulk mobility and moderate anisotropy, and thus most of the research was devoted to the fabrication of 4H-SC electronic devices. In particular, this was quite exciting for power device manufacturers because, compared to conventional semiconductors such as silicon, SiC has higher blocking voltages and can keep its operation capabilities up to much higher temperatures. Moreover, at higher voltages, above say~ 10 kV, bipolar SiC devices are preferred to unipolar ones because they have lower on-state voltage drops. Consequently, extensive research programs for the development of PiN diodes were initiated at research laboratories of a few large electrical manufacturers as well as some universities. However, tests on the reliability of these diodes turned out to be disappointing because it was discovered that 4H-SiC PiN diodes rapidly degrade in operation even at ambient temperatures (1). This effect exhibited itself by a rapid increase in the forward voltageVf drop with operation time and was found to be associated with a rapid increase in the number and extent of intrinsic stacking faults (ISFs) in the active region of the diode (2). This can be seen in electroluminescence (EL) patterns in Fig. 1 revealing optical activity of stacking faults and partial dislocations imaged in different