Isohashi Ai, Bui P V, Toh D, Matsuyama S, Sano Y, Inagaki K, Morikawa Y, Yamauchi K
Department of Precision Science and Technology, Graduate School of Engineering, Osaka University, Osaka 565-0871, Japan.
Appl Phys Lett. 2017 May 15;110(20):201601. doi: 10.1063/1.4983206.
Chemical etching of SiC was found to proceed in pure water with the assistance of a Pt catalyst. A 4H-SiC (0001) wafer was placed and slid on a polishing pad in pure water, on which a thin Pt film was deposited to give a catalytic nature. Etching of the wafer surface was observed to remove protrusions preferentially by interacting with the Pt film more frequently, thus flattening the surface. In the case of an on-axis wafer, a crystallographically ordered surface was obtained with a straight step-and-terrace structure, the height of which corresponds to that of an atomic bilayer of Si and C. The etching rate depended upon the electrochemical potential of Pt. The vicinal surface was observed at the potential at which the Pt surface was bare. The primary etching mechanism was hydrolysis with the assistance of a Pt catalyst. This method can, therefore, be used as an environmentally friendly and sustainable technology.
研究发现，在铂催化剂的辅助下，碳化硅（SiC）在纯水中会发生化学蚀刻。将一片4H-SiC（0001）晶片放置在纯水中的抛光垫上并滑动，在该抛光垫上沉积了一层薄铂膜以赋予其催化特性。观察到晶片表面的蚀刻通过与铂膜更频繁地相互作用而优先去除突起，从而使表面变平。对于轴上晶片，获得了具有直台阶和平台结构的晶体学有序表面，其高度对应于硅和碳原子双层的高度。蚀刻速率取决于铂的电化学势。在铂表面裸露的电位下观察到了邻晶面。主要蚀刻机制是在铂催化剂的辅助下进行水解。因此，该方法可作为一种环境友好且可持续的技术。
