High quality GaN-on-SiC with low thermal boundary resistance by employing an ultrathin AlGaN buffer layer
High quality GaN-on-SiC with low thermal boundary resistance by employing an ultrathin AlGaN buffer layer
复制标题
采用超薄 AlGaN 缓冲层，实现低热边界电阻的高质量 GaN-on-SiC
DOI：
10.1063/5.0037796
复制
发表时间：
2021-02-01
影响因子：
4
通讯作者：
Shen, Bo
中科院分区：
文献类型：
--
作者：
Feng, Yuxia;Sun, Huarui;Shen, Bo
采用低Al含量的AlGaN缓冲层，在SiC衬底上制备了高质量的GaN薄膜，并获得了低热边界电阻（TBR）。与传统的厚AlN缓冲层相比，AlN缓冲层不仅可以提高后续GaN层的晶体质量，而且可以同时降低GaN/SiC界面处的TBR。通过用三甲基铝对SiC衬底进行预处理，然后以增强的横向生长速率生长GaN，引入了掺杂AlGaN缓冲层。增强的横向生长速率有助于在GaN层中形成基面堆垛层错（BSF），其中BSF可以显著降低穿透位错密度。我们揭示了潜在的机制，降低TBR和位错密度的缓冲层。我们建议这项工作是非常重要的性能改善和降低成本的更高的功率GaN上SiC电子。
High quality GaN films on SiC with low thermal boundary resistance (TBR) are achieved by employing an ultrathin low Al content AlGaN buffer layer. Compared with the conventional thick AlN buffer layer, the ultrathin buffer layer can not only improve the crystal quality of the subsequent GaN layer but also reduce the TBR at the GaN/SiC interface simultaneously. The ultrathin AlGaN buffer layer is introduced by performing a pretreatment of the SiC substrate with trimethylaluminum followed by the growth of GaN with an enhanced lateral growth rate. The enhanced lateral growth rate contributes to the formation of basal plane stacking faults (BSFs) in the GaN layer, where the BSFs can significantly reduce the threading dislocation density. We reveal underling mechanisms of reducing TBR and dislocation density by the ultrathin buffer layer. We propose this work is of great importance toward the performance improvement and cost reduction of higher power GaN-on-SiC electronics.