Direct observation of layer-stacking and oriented wrinkles in multilayer hexagonal boron nitride
Lingxiu Chen, Kenan Elibol, Haifang Cai, Chengxin Jiang, Wenhao Shi, Chen Chen, Hui Shan Wang, Xiujun Wang, Xiaojing Mu, Chen Li, Kenji Watanabe, Takashi Taniguchi, Yufeng Guo, Jannik C Meyer, Haomin Wang
Abstract
Abstract Hexagonal boron nitride ( h -BN) has long been recognized as an ideal substrate for electronic devices due to its dangling-bond-free surface, insulating nature and thermal/chemical stability. These properties of the h -BN multilayer are mainly determined by its lattice structure. Therefore, to analyse the lattice structure and orientation of h -BN crystals becomes important. Here, the stacking order and wrinkles of h -BN are investigated by transmission electron microscopy. It is experimentally confirmed that the layers in the h -BN flakes are arranged in the AA′ stacking. The wrinkles in a form of threefold network throughout the h -BN crystal are oriented along the armchair direction, and their formation mechanism was further explored by molecular dynamics simulations. Our findings provide a deep insight about the microstructure of h -BN and shed light on the structural design/electronic modulations of two-dimensional crystals.