哌嗪对硅衬底CMP速率影响的机理  

Mechanism of the Effect of Piperazine on the CMP Rate of Silicon Substrate

作　　者：刘文博 罗翀 王辰伟 岳泽昊 栾晓东 邵祥清 李瑾 Liu Wenbo;Luo Chong;Wang Chenwei;Yue Zehao;Luan Xiaodong;Shao Xiangqing;Li Jin(School of Electronic and Information Engineering,Hebei University of Technology,Tianjin 300130,China;Innovation and Research Institute(Shijiazhuang),Hebei University of Technology,Shijiazhuang 050299,China;School of Electronic Engineering,Jiangsu Ocean University,Lianyungang 222000,China;Semiconductor Technology Innovation Center(Beijing)Corporation,Beijing 100176,China)

机构地区：[1]河北工业大学电子信息工程学院,天津300130 [2]河北工业大学创新研究院(石家庄),石家庄050299 [3]江苏海洋大学电子工程学院,江苏连云港222000 [4]北方集成电路技术创新中心(北京)有限公司,北京100176

出　　处：《微纳电子技术》2025年第2期165-174,共10页Micronanoelectronic Technology

基　　金：国家自然科学基金(62104087);中国博士后基金(2024M751207);河北工业大学创新研究院(石家庄)石家庄市科技合作专项基金(SJZZXB23003)。

摘　　要：为了在硅衬底化学机械抛光(CMP)过程中提高对硅片的去除速率,利用实验与密度泛函理论(DFT)计算相结合的方式研究了绿色环保添加剂哌嗪对硅片表面的作用机理。Zeta电位测试结果表明哌嗪的加入使磨料与抛光硅片表面的Zeta电位降低,二者间静电排斥力减小,吸附程度增加,增大了机械作用。接触角测试结果发现哌嗪的加入使抛光液在硅片表面的接触角更小,具有良好的润湿性能。抛光液可以更好地与晶圆表面接触,使去除速率加快。同时通过摩擦系数测试进一步证明了哌嗪提高了抛光过程中的摩擦力,从而提升了抛光速率。X射线光电子能谱(XPS)分析显示,哌嗪与硅片表面发生了化学反应,生成了新的Si—N键,对临近的Si—Si键产生极化,使其在磨料作用下更容易被去除。采用DFT的量子化学计算和分子动力学模拟更深入地表明了哌嗪和硅在分子水平上产生了化学吸附。结果显示,当磨料质量分数为0.5%、哌嗪质量分数为0.5%时,去除速率可达580 nm/min。此外,哌嗪作为一种相对绿色环保的添加剂,更适合实际生产应用。In order to improve the removal rate of silicon wafer during chemical mechanical polishing(CMP)of silicon substrate,the effect mechanism of environmentally friendly piperazine on the surface of silicon wafer was studied by combining experiment and density functional theory(DFT)calculation.Zeta potential test results show that the addition of piperazine reduces the Zeta potential and electrostatic repulsion between the surface of the abrasive and polished silicon wafer,increasing the adsorption degree and the mechanical effect.The contact angle test results show that addition of piperazine makes the contact angle of the slurry on the surface of the silicon wafer smaller and has good wettability.The slurry can better contact with the wafer surface and speed up the removal rate.At the same time,the friction coefficient test further proves that piperazine increases the friction force in the polishing process,thereby increasing the polishing rate.X-ray photoelectron spectroscopy(XPS)analysis shows that piperazine reacts with the surface of silicon wafer to form a new Si—N bond,which polarizes the adjacent Si—Si bond and makes it easier to be removed under the action of abrasives.The quantum chemical calculations and molecular dynamics simulations using DFT further demonstrate that piperazine and silicon on the molecular level produce the chemical adsorption.The results show that the removal rate can reach 580 nm/min when the mass fraction of abrasive is 0.5%and the mass fraction of piperazine is 0.5%.In addition,piperazine,as a relatively green and environmentally friendly additive,is more suitable for actual production applications.

关 键 词：化学机械抛光(CMP) 硅衬底 哌嗪 去除速率 密度泛函理论(DFT)计算 

分 类 号：TN305.2[电子电信—物理电子学]