Directional etching for high aspect ratio nano-trenches on hexagonal boron nitride by catalytic metal particles. (1st April 2022)

• Record Type: Journal Article
• Authors: Chen, Chen; He, Li; Jiang, Chengxin; Chen, Lingxiu; Wang, Hui Shan; Wang, Xiujun; Kong, Ziqiang; Mu, Xiaojing; Wei, Zhipeng; Watanabe, Kenji; Taniguchi, Takashi; Wu, Tianru; Zhang, Daoli; Wang, Haomin
• Is Part Of: 2D materials. Volume 9:Number 2(2022)
• Publication Date: 2022-04-01
• Subjects: hexagonal boron nitride -- nano-trenches -- nano-particles -- directional etching; Graphene -- Periodicals; Materials science -- Periodicals; Nanostructured materials -- Periodicals; 620.115
• DOI: 10.1088/2053-1583/ac5461
• Languages: English
• ISSNs: 2053-1583

Abstract

Abstract: Stimulated by the attractive performance of multi-dimensional heterostructures involving hexagonal boron nitride ( h BN), intense attentions have been paid to creation of sharp boundary/interface, which could bring h BN nano-structures additional appealing physical properties. However, the lack of controllable synthesis limits further experimental investigation on h BN nano-structures. Here, the directional etching of transitional metal nano-particles (NPs) on the surface of h BN to produce nano-trenches with sharp edges was systematic investigated. It is found that, only Pt and Ir NPs can produce armchair-oriented nano-trenches at low H2 partial pressure, while other transitional metals lead to zigzag oriented nano-trenches. The density and width of the nano-trenches always increase with etching temperature and the pre-treated solution concentration while the trench orientation depends on both H2 partial pressure and etching temperature. The aspect ratio of nano-trenches may reach several thousand under optimized conditions. The method exhibited here shines a light on edge-selective patterning of 2D crystals.