A surface flattening mechanism of a heteroepitaxial film consisting of faceted non-flat top twins: [1(1)over-bar0(3)over-bar]-oriented GaN films grown on m-plane sapphire substrates

作者：Jue Miyeon; Yoon Hansub; Lee Hyemi; Lee Sanghwa; Kim Chinkyo^*

来源：Applied Physics Letters, 2014, 104(9): 092110.

DOI：10.1063/1.4867705

We carried out experiments and computational simulations in order to answer a yet unanswered question about a surface flattening mechanism of a [1 (1) over bar0 (3) over bar]-oriented GaN film consisting of faceted non-flat top twins. Our results revealed that an overgrowth of one variant of twins over the other, which was manifested only at a thickness larger than a few microns due to a slight asymmetric crystallographic tilt (1.0 degrees +/- 0.4 degrees) of twins, played a key role in a surface flattening mechanism. In addition, we experimentally demonstrated that GaN grown on a SiO2-patterned m-plane sapphire substrate had no asymmetric tilt and that no surface flattening occurred.

• 出版日期2014-3-3