摘要
化学机械抛光(chemical mechanical polishing,CMP)是SiC衬底平坦化的关键技术,目前针对CMP工艺已有大量研究,但磨粒、溶液介质与SiC表面协同作用的机理并不明确。分子动力学(molecular dynamics,MD)模拟是基于牛顿运动定律和量子力学原理,用于揭示物质微观结构和性质之间相互作用的模拟方法,目前被广泛应用于SiC表面去除机理研究。首先分析SiC精密抛光MD模拟常用的势函数,并总结其应用领域,然后对现有的SiC化学机械抛光MD模拟研究进行整合分析。结果表明:Tersoff势函数在机械行为方面的研究中应用较多,而研究SiC表面化学反应和吸附行为使用ReaxFF较多。SiC衬底精密抛光的MD模拟主要分为3类:SiC材料性能、磨粒磨削、SiC表面化学反应。目前大部分研究集中于磨粒与SiC表面的机械行为作用,而对化学反应机理的研究相对较少。未来研究的重点在于利用ReaxFF通过MD模拟研究SiC在各种条件下的反应机理,构建更多势函数以适应不同抛光条件,建立综合模型考虑多种因素对表面相互作用的影响。
Significance:Silicon carbide(SiC),as a representative material of third-generation semiconductors,holds vast potential for applications in microelectronics,optoelectronics,aerospace,and energy.However,its high hardness and chemical stability pose significant challenges for processing.Chemical mechanical polishing(CMP)is a crucial technology for planarizing SiC substrates.It can effectively remove the damaged layer and impurities on the wafer surface,achieve a high degree of planarization,thereby enhance the performance and reliability of SiC devices.Extensive research has been conducted on CMP processes,yet the mechanisms of interaction and synergy among abrasives,solution media,and SiC surfaces remain unclear.Molecular dynamics(MD)simulation,based on Newton's laws of motion and the principles of quantum mechanics,is a simulation method used to reveal the interactions between the microscopic structure and properties of matter.It is currently widely applied in the study of SiC surface removal mechanisms.By simulating the scratching behavior of abrasives on SiC surfaces,changes in material morphology,crystal structure,temperature,cutting force,and potential energy can be observed,thereby providing deeper insights into polishing mechanisms.This in-depth understanding of polishing mechanisms aids in optimizing polishing process parameters,improving polishing efficiency,and surface quality.Meanwhile,during the SiC CMP process,certain components in the polishing solution interact with the SiC surface,potentially involving a series of chemical reactions.MD simulation can reveal the detailed mechanisms of these chemical reactions,including the reaction pathways,reaction rates,and reaction products,thereby facilitating a deeper understanding of the material removal mechanism during the polishing process and providing a theoretical basis for optimizing polishing processes.Progress:The article first analyzes the potential functions commonly used in MD simulations for SiC precision polishing and summarizes their application fields.It then integrates and analyzes existing MD simulation studies on SiC CMP.MD simulations for SiC substrate precision polishing are mainly classified into three categories:SiC material properties,abrasive grinding,and SiC surface chemical reactions.The Tersoff potential function has been widely applied in the preparation and properties of SiC materials,demonstrating excellent simulation results.It has become the most popular potential function for MD simulations of SiC materials.The Tersoff/ZBL potential function enhances the Tersoff potential function by incorporating the ZBL potential,thus adding short-range interactions and providing a more accurate description of short-range atomic collisions.The ABOP potential function,based on the Tersoff potential function,allows for the breaking of chemical bonds,making it more suitable for simulating wear behavior.The Vashishta potential function is well-suited for accurately simulating the deformation of ionic and covalent bonds in 3C-SiC,including bending and stretching.It is widely used in simulations involving impact behavior and nanoindentation of SiC.The advantage of the ReaxFF lies in its ability to simulate the formation and breaking of bonds during chemical reactions,making it suitable for simulating chemical reactions,adsorption,and other phenomena on SiC surfaces.Conclusions and Prospects:Currently,many aspects of the CMP mechanism of SiC materials remain unclear.MD simulations can be utilized to study the interaction mechanisms between liquids,oxides,and surfaces during CMP,such as charge transfer and surface adsorption.Most research has focused on the mechanical interactions between abrasives and SiC surfaces,with relatively little attention paid to chemical reaction mechanisms.Future research will emphasize using the ReaxFF through MD simulations to study the reaction mechanism of SiC under various conditions,developing more potential functions to accommodate different polishing conditions,and establishing comprehensive models to consider the impact of multiple factors on surface interactions.During MD simulations of SiC oxidation mechanisms,different potential functions have distinct application fields.Although the ReaxFF reactive force field can effectively simulate SiC surface oxidation reactions,using the Tersoff potential function to simulate the interaction between SiC and abrasives is more reasonable.Due to the high modeling proficiency required to establish mixed potential function models combining the ReaxFF reactive force field with other potential functions,researchers often adopt the ReaxFF single intermolecular potential for calculations.If oxidation reactions and abrasive grinding occur simultaneously during the calculation process,it may not accurately describe the SiC surface interaction mechanisms.Therefore,combining the ReaxFF with other potential functions to achieve MD simulation of chemical mechanical polishing under the combined action of multiple factors will be a direction for future research.
作者
张佳誉
孟二超
孙建林
季建忠
ZHANG Jiayu;MENG Erchao;SUN Jianlin;JI Jianzhong(University of Science and Technology Beijing,School of Materials Science and Engineering,Beijing 100083,China;Trojan(Suzhou)Material Technology Co.,Ltd.,Suzhou 215127,Jiangsu,China)
出处
《金刚石与磨料磨具工程》
北大核心
2025年第4期504-516,共13页
Diamond & Abrasives Engineering
关键词
碳化硅
分子动力学模拟
化学机械抛光
去除机理
辅助增效
silicon carbide
molecular dynamics simulation
chemical mechanical polishing
removal mechanism
assisting enhancement
