Zhou Yuqi, Xu Kezhong, Gao Yuhan, Yu Ziniu, Zhu Fulong
Institute of Microsystems, School of Mechanical Science and Engineering, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan, Hubei Province, 430074, P. R. China.
Phys Chem Chem Phys. 2024 Nov 7;26(43):27791-27806. doi: 10.1039/d4cp03544e.
Determination of chemical effects involved in material removal during the polishing process of 4H-SiC has been a challenge. In this study, the polishing processes of 4H-SiC under the action of diamond and SiO abrasive in different concentrations of HO solutions are investigated by reactive force field molecular dynamics simulations. It is found that 4H-SiC can be oxidized by HO solution at the atomic scale, but the chemical reaction alone does not lead to material removal. An increase in the concentration of HO solution and the mechanical action of abrasives can promote the oxidation of 4H-SiC. Since the mechanical removal dominates material removal when polishing 4H-SiC with diamond abrasive, there is no clear pattern in the effect of HO solution concentration on material removal. Nevertheless, the removal of atoms associated with chemical bonds dominates material removal when polishing 4H-SiC with SiO abrasive. Therefore, the damage and atomic removal of 4H-SiC are lower. Since the HO solution can increase the total number of bonds between 4H-SiC and SiO abrasive, an increase in the concentration of HO solution can improve the material removal rate. These findings can provide guidance for the 4H-SiC polishing process in terms of abrasive and oxidizer selection.
确定4H-SiC抛光过程中材料去除所涉及的化学效应一直是一项挑战。在本研究中，通过反应力场分子动力学模拟研究了4H-SiC在不同浓度的HO溶液中在金刚石和SiO磨料作用下的抛光过程。研究发现，4H-SiC在原子尺度上可被HO溶液氧化，但仅化学反应不会导致材料去除。HO溶液浓度的增加和磨料的机械作用可促进4H-SiC的氧化。在用金刚石磨料抛光4H-SiC时，由于机械去除主导材料去除，因此HO溶液浓度对材料去除的影响没有明显规律。然而，在用SiO磨料抛光4H-SiC时，与化学键相关的原子去除主导材料去除。因此，4H-SiC的损伤和原子去除较低。由于HO溶液可增加4H-SiC与SiO磨料之间的键总数，HO溶液浓度的增加可提高材料去除率。这些发现可为4H-SiC抛光过程中磨料和氧化剂的选择提供指导。
