Department of Materials Science & Engineering, Center for 2-Dimensional & Layered Materials, The Pennsylvania State University, University Park, PA 16802, United States of America. 2D Crystal Consortium, Materials Research Institute, The Pennsylvania State University, University Park, PA 16802, United States of America.
Nanotechnology. 2018 Nov 23;29(47):47LT02. doi: 10.1088/1361-6528/aae0bb. Epub 2018 Sep 12.
The experimental realization of two-dimensional (2D) gallium nitride (GaN) has enabled the exploration of 2D nitride materials beyond boron nitride. Here we demonstrate one possible pathway to realizing ultra-thin nitride layers through a two-step process involving the synthesis of naturally layered, group-III chalcogenides (GIIIC) and subsequent annealing in ammonia (ammonolysis) that leads to an atomic-exchange of the chalcogen and nitrogen species in the 2D-GIIICs. The effect of nitridation differs for gallium and indium selenide, where gallium selenide undergoes structural changes and eventual formation of ultra-thin GaN, while indium selenide layers are primarily etched rather than transformed by nitridation. Further investigation of the resulting GaN films indicates that ultra-thin GaN layers grown on silicon dioxide act as effective 'seed layers' for the growth of 3D GaN on amorphous substrates.
二维（2D）氮化镓（GaN）的实验实现使人们能够探索超越氮化硼的二维氮化物材料。在这里，我们通过两步法演示了一种可能的途径来实现超薄氮化物层，该方法涉及合成天然层状的 III 族硫属化物（GIIIC），然后在氨中退火（氨解），导致 2D-GIIIC 中的硫属元素和氮物种的原子交换。氮化对硒化镓和硒化铟的影响不同，其中硒化镓经历结构变化并最终形成超薄 GaN，而硒化铟层主要通过氮化被刻蚀而不是转化。对所得 GaN 薄膜的进一步研究表明，在二氧化硅上生长的超薄 GaN 层可作为在非晶衬底上生长 3D GaN 的有效“种子层”。
