GaN is a favorable martial for future efficient high voltage power switches. GaN has not dominated the power electronics market due to immature substrate, homoepitaxial growth, and immature processing technology. Understanding the impact of the substrate and homoepitaxial growth on the device performance is crucial for boosting the performance of GaN. In this work, we studied vertical GaN PiN diodes that were fabricated on non-homogenous Hydride Vapor Phase Epitaxy (HVPE) substrates from two different vendors. We show that defects which stemmed from growth techniques manifest themselves as leakage hubs. Different non-homogenous substrates showed different distribution of those defects spatially with the lesser quality substrates clustering those defects in clusters that causes pre-mature breakdown. Energetically these defects are mostly mid-gap around 1.8Ev with light emission spans from 450nm to 700nm. Photon emission spectrometry and hyperspectral electroluminescence were used to locate these defects spatially and energetically.

中文翻译：

---

中带隙缺陷对垂直氮化镓二极管影响的研究

GaN 是未来高效高压电源开关的有利材料。由于衬底不成熟、同质外延生长和加工技术不成熟，GaN并未主导电力电子市场。了解衬底和同质外延生长对器件性能的影响对于提高 GaN 的性能至关重要。在这项工作中，我们研究了在来自两个不同供应商的非同质氢化物气相外延 (HVPE) 衬底上制造的垂直 GaN PiN 二极管。我们表明，源于增长技术的缺陷表现为泄漏中心。不同的非均质基板显示出这些缺陷在空间上的不同分布，质量较差的基板将这些缺陷聚集在导致过早击穿的集群中。从能量上讲，这些缺陷大多是 1.8Ev 左右的中间间隙，发光范围从 450nm 到 700nm。光子发射光谱法和高光谱电致发光被用来在空间和能量上定位这些缺陷。