Mg diffusion and activation along threading dislocations in GaN
Mg diffusion and activation along threading dislocations in GaN
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GaN 中沿螺纹位错的 Mg 扩散和激活
DOI：
10.1063/5.0009596
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发表时间：
2020
影响因子：
4
通讯作者：
K. Hono
中科院分区：
文献类型：
--
作者：
W. Yi;Ashutosh Kumar;Jun Uzuhashi;T. Kimura;R. Tanaka;S. Takashima;M. Edo;Yongzhao Yao;Y. Ishikawa;Jun Chen;T. Ohkubo;T. Sekiguchi;K. Hono
p-GaN的精确控制是GaN基功率器件发展的关键问题。Mg作为受主通常用于p型掺杂;然而，Mg通过穿透位错（TD）的扩散尚未得到很好的解决。为了阐明Mg扩散和激活沿着TD，我们已经进行了系统的表征Mg注入同质外延GaN层上生长的独立衬底。通过阴极发光（CL）鉴定来自某些TD的活性Mg相关的供体-受体对（DAP）发射。位错与DAP发射和不发射的结构和成分的基础上，蚀刻坑，透射电子显微镜，和原子探针断层扫描。镁分布周围的边缘和混合型TD的直接证据。不同类型TDs的Mg含量和掺入状态存在显著差异。
The precise control of p-GaN is a crucial issue for developing GaN-based power devices. Mg as an acceptor is commonly used in p-type doping; however, the Mg diffusion through threading dislocations (TDs) has not been well addressed. To clarify the Mg diffusion and activation along TDs, we have performed a systematic characterization of a Mg-implanted homoepitaxial GaN layer grown on a freestanding substrate. Active-Mg related donor–acceptor pair (DAP) emission from certain TDs is identified by cathodoluminescence (CL). Dislocations with and without DAP emission are investigated structurally and compositionally based on etch pits, transmission electron microscopy, and atom-probe tomography. Direct evidence of Mg distribution around edge- and mixed-type TDs is obtained. There exists a significant difference in the Mg concentration and incorporation states between different types of TDs.