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乙二胺在硅化学机械抛光中的作用机制∗

  • 汪海波1,2

    机 构：

    1. 合肥师范学院电子信息与电气工程学院 合肥 230601

    2. 电子信息系统仿真设计安徽省重点实验室 合肥 230601

    ×
  • ， 蒋先伟1,2

    机 构：

    1. 合肥师范学院电子信息与电气工程学院 合肥 230601

    2. 电子信息系统仿真设计安徽省重点实验室 合肥 230601

    ×

1. 合肥师范学院电子信息与电气工程学院 合肥 230601；
2. 电子信息系统仿真设计安徽省重点实验室 合肥 230601；

Mechanism Study on Silicon CMP Using Ethylenediamine

  • WANG Haibo1,2

    Affiliation：

    1. School of Electronic Information and Electrical Engineering, Hefei Normal University, Hefei 230601 , China

    2. Anhui Province Key Laboratory of Simulation and Design for Electronic Information System, Hefei 230601 , China

    ×
  • ， JIANG Xianwei1,2

    Affiliation：

    1. School of Electronic Information and Electrical Engineering, Hefei Normal University, Hefei 230601 , China

    2. Anhui Province Key Laboratory of Simulation and Design for Electronic Information System, Hefei 230601 , China

    ×

1. School of Electronic Information and Electrical Engineering, Hefei Normal University, Hefei 230601 , China；
2. Anhui Province Key Laboratory of Simulation and Design for Electronic Information System, Hefei 230601 , China；

作者简介:

汪海波(通信作者),男,1983年出生,博士,副教授。主要研究方向为半导体加工。E-mail:john20140105@163.com;

蒋先伟,女,1983年出生,博士,副教授。主要研究方向为集成电路设计。E-mail:279123127@qq.com

中图分类号:TH117

DOI:10.11933/j.issn.1007-9289.20210413002

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目录contents

    摘要

    利用胶体二氧化硅在胺的辅助下对硅片进行抛光是微电子工业中的一种典型制造工艺,其动力学过程仍然不清楚。 研究了在硅抛光中加入不同浓度乙二胺( EDA)对抛光速率的影响,结果表明 EDA 浓度提高时,硅的抛光速率逐渐增大,并且在质量分数 5%时增加 74. 5%。 为了揭示其中的作用机理,对 EDA 和 Si 在水中的电离性质作了分析,对硅片表面在 EDA 碱性溶液中的接触角以及 Si 经过 EDA 溶液浸泡后的表面作了 X 射线光电子能谱(XPS)测试,进一步采用基于反应力场的分子动力学模拟了动态反应过程。 分析表明 EDA 和硅片表面不仅有强烈的库仑吸附作用,且 Si 和 EDA 通过 Si-N 进一步形成化学键,其中 EDA 中的 N 原子与硅表面原子能形成两种结构,使附近的 Si-Si 和 Si-O 键极化。 基于这些测试,最终解释了硅在含有 EDA 碱性抛光液中的抛光动力学过程,此作用机制可为硅衬底加工的抛光液研制提供一定的技术指导。

    Abstract

    Silicon polishing using colloidal silica with assistance of amine is a typical manufacturing process in micro electronics industry,which kinetic process is still unclear. The effect of different concentrations of ethylenediamine (EDA) on the polishing rate was studied. The results showed that the polishing rate of silicon increased gradually with the increase of EDA concentration, and by 74. 5% at 5%. In order to reveal the mechanism of the action, the ionization properties of EDA and Si in water were analyzed, the contact angle of the silicon surface in EDA alkaline solution and the X-ray photoelectron spectroscopy (XPS) of Si soaked in EDA solution were tested, the dynamic reaction process was also simulated by the molecular dynamic simulation based on reaction force field. The results show that the surface of EDA and silicon wafer not only has strong Coulomb adsorption, but also Si and EDA form chemical bonds through Si-N atoms in EDA, which polarizes the nearby Si-Si and Si-O bonds. Based on these tests, the polishing dynamics of silicon in the alkaline polishing slurry containing EDA is explained. The mechanism could provide some technical guidance for the development of polishing slurry for silicon substrate processing.

  • 0 前言

  • 使用添加纳米级胶体二氧化硅体系的化学机械抛光是电子级硅片加工的关键制造工艺,即所谓的粗抛和精抛。粗抛的目的是在大约几十毫米的波长范围内抛光硅晶片表面形貌,而精抛的目的是在几微米和几毫米之间的波长范围内抛光硅晶片表面形貌[1-2]。随着硅片厚度的增大和芯片尺寸的减小, 提高加工效率成为了抛光的研究热点之一[3]。

  • 为了提高硅的抛光速率,通常在传统的碱性溶液中加入各种添加剂。双氧水作为氧化物,在其体积浓度低于1%时,能够增强硅-水系统的电化学反应,故可以提高硅的抛光速率[4]。离子浓度对抛光速率有一定影响,研究发现硫酸钾浓度增加使得颗粒运动速度提高,从而提高抛光速率[5]。含有 α 胺的有机胺能提高多晶硅的抛光速率。它的机制是 α 胺中的N原子能够极化衬底表面上的硅[6]。有机和无机pH值调节剂被认为是影响抛光速率的关键因素之一,杨金波等的结果表明有机碱pH调节剂抛光速率要快于无机碱,原因在于其对钝化膜形成有重要影响,以及有机碱的pH缓冲作用能维持抛光化学环境[7]。另外氢氧化铵和有机胺作为pH值调节剂同时加入FA/O型表面活性剂,也被用于硅抛光中以提高抛光速率[1]。有文献指出,在硅溶胶中加入乙二胺四乙酸(EDTA)或者乙二胺四乙酸二钠等螯合剂能提高抛光速率,但是这种螯合物溶解度较低或对硅溶胶稳定性会产生影响[8]。有更多的文献指出,使用乙二胺、哌嗪等有机胺或胺的衍生物均能有效提高抛光速率[9-12]。 LONCKI等[13] 提出采用盐和多胺类化合物组合能够提高抛光效率,其中胺作为pH值缓冲剂,pH值在8.0~11.0之间;同样,KAWASE等[14-16]指出使用质量浓度在2%~4%的EDA,pH值范围在10.5~12.0之间能够有效提高抛光速率,但并没有说明其作用机制。总之,人们已经认识到EDA及其衍生物对硅抛光速率有明显的提升作用。但对于其作用机制有pH值缓冲、极化硅原子和螯合作用等多种说法,目前并没有统一的结论。复杂的作用机制给进一步提升硅加工效率、研制更加高效的抛光液设置了障碍。因此,人们必须更深入地理解胺及其衍生物的详细作用过程, 特别是分子层面的作用机制。

  • 基于这种考虑,本文研究了在硅抛光中加入不同浓度EDA对抛光速率的影响并与不加的情况作了对比。通过X射线光电子能谱(XPS) 检测浸泡EDA碱性溶液中后的硅片表面各元素状态。更进一步,利用反应力场从分子动力学角度模拟了抛光的微观动力学过程。综合多种测试结果,尝试分析了EDA辅助下的硅抛光动力学过程。

  • 1 试验和模拟部分

  • 1.1 试验

  • 抛光试验采用CP-4型抛光机,压力和转速分别为27.579 028kPa和100r/min,抛光液流速设定为120mL/min。抛光液采用80nm、质量比5%的硅溶胶(以下均采用质量比) 配置,pH值采用8%的KOH和8%H2 SO4 调节。每片抛光时间设置为10min。通过电子天平测量抛光前后硅的重量,抛光速率根据式(1)计算:

  • RR=M2-M1ρ⋅s⋅t⋅107
    (1)

  • 式中,RR 是抛光速率,M 2 和M 1 分别是抛光前和抛光后的质量,单位为g;ρ 是硅衬底密度(根据厂家提供为2.3g/cm 3); s 为硅片面积( 4in、 ( 100) 型) (1in=25.4mm),t 是抛光时间,单位为h;将抛光并清洗后的硅片浸泡在pH为11.0的溶液或含有1%EDA的碱性溶液中10min后,经过氮气干燥, 采用Perkin-Elmer PHI 5000C型XPS测试硅片表面各元素的化学态(测试条件为Li Kα 射线源、真空度10-10 Torr)(1Torr=133.322 4Pa),分析EDA与Si的成键情况;用DSAeco型接触角仪分别测试纯水和含有不同浓度EDA的碱性溶液在抛光后硅片表面上的接触角,分析EDA溶液与Si表面的吸附作用。

  • 1.2 模拟

  • 用反应力场模拟硅(100)面在碱性溶液中的分子动力学过程,阐明硅抛光的微观机理[17-18]。构建的硅(100) 衬底和EDA水溶液模型如下:①使用NVT系综制备包含1 800个Si原子的硅(100) 衬底,其中温度设定为300K。 ②同样,用NVT系综制备包含3 600个H2O和180个EDA分子的溶液(厚度为1nm),模型的设置参考了文献[19]。硅层底部分为固定层和刚性约束层。系统经过几何优化后,使用带有NVE系综的ReaxFF力场模拟反应动力学,时间步长设置为0.5fs [20-21]。在x和y两个方向上应用周期性边界条件;以10kB/ps的速率将系统从0缓慢升温至300K,使用阻尼常数为100fs的Langevin恒温器将温度控制在300K; 反应时间25ps,平衡时间100ps;所有ReaxFF MD模拟中使用的力场都采用Si/Ge/H力场,用Verlet算法对原子轨迹进行积分。

  • 2 结果与讨论

  • 图1 显示了硅抛光速率与EDA浓度之间的关系。从图中可以看出,当抛光液中不加入EDA时, 抛光速率为307.3nm/min;加入EDA后,抛光速率快速上升;当加入的浓度为5%EDA时,抛光速率达到536.1nm/min,速率提升达74.5%。对比硅在单独KOH溶液中的抛光情况,可以很清晰发现EDA能够提升抛光速率,并且随着EDA浓度升高,速率提升越高。

  • 图1 pH为11.0时,硅的抛光速率与EDA浓度的关系 (插图为不同浓度EDA溶液、纯水和KOH溶液在硅表面上形成的接触角)

  • Fig.1 Removal rate as a function of EDA concentration at pH 11.0 (The insert graphic is contact angle vs.EDA aqueous with different concentration, purity water and KOH solution)

  • EDA在室温水中的解离常数pKa1=9.86,电导率为632.5 μs/cm,黏度为1.05mPa·s [22]。这意味着EDA分子在水中能够解离,过程由式(2)表示:

  • NH2(CH)2NH2+H2O⇌NH2(CH)2NH3++OH-
    (2)

  • 解离产物包含带正电的NH2(CH)2NH3 +和带负电的OH-。因此,EDA可以为刻蚀硅片提供反应物[23]。

  • 此外,已经被广泛的试验和测试所证实,硅晶片抛光后表面终端是Si-H或Si-OH结构,呈现负电荷[24]。而EDA水解产物NH2(CH)2NH2 + 呈现正电荷,与硅抛光晶片表面电荷相反。因此,EDA分子可以通过库仑或H键的相互作用吸附在硅表面, 这可以通过图1所示的接触角插图来证明。纯水在抛光后硅表面上形成的接触角约为84°,与文献 [25]报道的结果一致,表明抛光后硅表面是疏水的,原因是抛光后硅表面的终端是Si-H键;如果使用pH=11.0的KOH溶液,所形成的接触角和纯水的情况几乎相同;但进一步向水中加入EDA,接触角随着EDA浓度的增加而不断减小,当EDA浓度达到5%时,接触角只有47°。通过对比,可以发现EDA溶液在硅片上的接触角降低不仅是解离出来的OH-作用,因为KOH溶液并不能有效降低接触角,而更应该是EDA分子或者离子的直接作用。

  • 正如前面所提到的,这种相互作用的原因可能有很多种。除了广泛存在的静电库仑作用或氢键作用,是否会形成较强的化学键也需要考虑。 XPS具有高灵敏度,能够准确测试表面层化学元素的化学状态。将抛光后硅片表面浸没在pH为11.0的EDA的碱性溶液中10min,干燥后测试,进而推测EDA和硅的化学作用。测试结果如图2所示。为了便于对比,图中也同时显示出了KOH溶液浸泡硅表面后的XPS结果。

  • 图2a是硅表面的O 1s能谱图。在KOH溶液中产生的Si-O的O 1s是532.6eV,表明形成了氧化硅,这与文献中的结果一致[26];而在EDA的碱性溶液中产生的Si-O键其O 1s光谱是532.2eV,降低了0.4eV,表明EDA在碱性条件下影响硅的氧化,使得表面的Si-O键的键能发生偏移。

  • 图2b是硅表面的N 1s光谱,可以看出硅浸入KOH水溶液中,其表面不含N元素;当硅片浸入EDA后,则其表面含有EDA,能谱峰值位于398.5eV和400.1eV, 分别对应的是N-Si键和C-N键[27],这表明EDA参与了反应。

  • 硅的能谱测量结果如图2c所示。 99.3eV对应的Si2p光谱峰证明了Si-Si键的存在,这个峰值属于体硅。但经过EDA的碱性溶液中浸泡的Si2s光谱与经过KOH溶液浸泡的Si2s光谱不同。经过拟合,发现两种情况下,硅表面均存在102.5eV峰,证明了Si-O键的存在;而对于EDA浸没的情况,则多出了102.9eV峰,证明了N-Si键[28],这与图2b中得出的结果一致。 XPS结果证明了DANDU等[6]提出的,在硅表面胺可以通过N原子取代Si-H中的H原子与硅发生反应。

  • 由接触角和XPS的测量结果可以看出,EDA与硅的作用有静电和化学反应两方面。然而,上述测量是静态结果,不能直观地推测抛光的动态过程。因此,可以采用基于反应力场直接模拟EDA与硅表面反应的分子动力学过程,其已经被证明是硅化学机械抛光研究的有效方法[9,17-18]。

  • 在ReaxFF反应力场中,EDA的碱性溶液与硅的反应模拟如图3所示。其中,图3a所示的模型中共有4层:第一层是底部硅衬底原子的刚性层,在模拟仿真中被固定;第二层是主体硅的固定层;第三层是表面的自由硅层;第四层是EDA的碱性溶液。该模型的建立参考了文献[18]。图3b和3c分别是该模型侧视图和俯视图的模拟结果。硅表面以H2O、OH、H和EDA分子作为终端,通过高分辨率红外光谱[29]和Si-H2O反应模拟[30]已经被证明。 H终端可以形成两种,分别是一元结构Si-H和二元结构Si-H2。重要的是,由XPS结果与其他研究发现[31-32],硅还可以被氧化成Si-O-Si, Si-OH。同样,通过表面的Si-N键可以发现Si-EDA的形成,这与XPS结果一致。

  • 图2 硅浸泡KOH溶液和含有1%EDA的碱性溶液后O 1s(a)、N 1s(b)、Si2s和Si2p(c)的光电子能谱

  • Fig.2 Binding state of silicon immersing in 1%EDA aqueous obtained by XPS measurement compared with that immersing in KOH aqueous

  • 图3 使用ReaxFF反应力场对EDA的碱性溶液和硅反应的动力学模拟结果

  • Fig.3 Reaction simulation results of EDA aqueous and silicon using ReaxFF reactive force field.( a) Schematic of the simulation model; ( b) Side view of Si-EDA aqueous configuration after simulation; ( c) Top view of Si surface configuration after simulation; ( d) N-Si coordination number distribution after 0.1ps simulation, the insert is N-Si coordination number distribution after 25ps simulation.

  • 经过0.1ps模拟后N-Si的配位数分布如图3d所示,经过25ps模拟后N-Si的配位数分布也显示在图3d的插图中。通过对比可以看出,在初始反应过程中,大部分氮与硅原子没有成键;经过0.1ps后,部分EDA与Si反应形成N-Si结构,形成单配位,少量EDA与Si反应形成Si-N-Si,形成双配位。随着模拟时间的增加,反应产物由无键变为二配位, 表明EDA和Si的反应产物更倾向于Si-N-Si结构。

  • 化学机械协同作用主导了化学机械抛光过程, 化学机械抛光过程中Si-Si键断裂和Si-O键断裂是硅抛光的两种主要方式,在硅-水界面形成硅氧键的纯化学反应不能单独去除硅原子[9]。然而,加入水中的化学试剂会影响Si-Si和Si-O键的能量,从而导致更高的磨削率。与前人研究的硅去除机理结果相比[16-17,22],由于静电吸附,EDA水解产物在硅表面比水和羟基更容易吸附,如图4a所示。因此, EDA可以快速触碰到硅表面,这为进一步与硅原子反应提供了机会。一旦形成吸附,EDA与硅反应形成两种氮硅结合结构,如图4b所示。一种是单配位的形式,另外一种是双配位形式,XPS测量和分子动力学模拟揭示了这两种氮硅结合。氮与硅原子结合可以极化相邻的Si-Si键,该键被水或者溶解氧以及羟基进一步氧化形成氧化物,然后通过胶体二氧化硅的摩擦作用去除氧化物,如图4c所示。 Si-O和Si-Si键能强,室温下热能无法使其断裂。通过Si、N原子的结合形成N-Si和Si-N-Si两种结构,可以使Si-Si和Si-O键极化,这一点已被XPS测试所证实。图2a显示的分别由KOH和EDA的碱性溶液引起的氧化物中硅氧结合能从532.6eV减小到532.2eV,表明Si-O键被EDA极化。因此在相同的抛光剪切力下,EDA极化的Si-O键很容易断裂。当EDA浓度升高时,Si-O键被极化的可能性增大, 导致增加的去除速率,这可以说明图1中产生的现象。

  • 图4 硅与EDA的碱性溶液反应过程示意图

  • Fig.4 Schematic of silicon reaction process with EDA aqueous.(a) Absorption between EDA hydrolysis product and silicon surface by static electronic interaction; ( b) Dynamic reaction occurrence between EDA and silicon surface by two kind of N-Si coordination, one is N-Si structure, another is Si-N-Si structure; (c) Si-Si bond further oxidization.

  • 3 结论

  • 研究了EDA浓度对硅片化学机械抛光效率的影响,试验显示抛光速率随着EDA浓度的增加而迅速增加。通过分析EDA和硅片在水中的水解性质、测试两者的接触角、模拟反应动力学过程发现EDA对硅片抛光的作用机制如下:两者在水相中呈现相反电荷,具有较强的静电作用,使得EDA能够快速接触硅片表面;进而EDA可以通过Si-N键与硅表面发生反应,生成Si-N和Si-N-Si结构,使得与之链接的Si-O结合能从532.6eV移动到532.2eV,从而极化附近的Si-Si键,在硅溶胶的辅助下实现了快速抛光。从多角度、多层次研究了EDA的作用机制, 深入了分析了作用过程,研究结论对于硅化学机械抛光的效率进一步提升有一定的指导作用。

  • 参考文献

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    • [2] KIM S K,KIM Y H,PAIK U,et al.The Effect of the physicochemical properties of cellulosic polymers on the Si wafer polishing process[J].Journal of Electroceramics,2006,17(2-4):835-839.

    • [3] 徐嘉慧,康仁科,董志刚,等.硅片化学机械抛光技术的研究进展[J].金刚石与磨料磨具工程,2020,238(40):24-33.XU Jiahui,KANG Renke,DONG Zhigang,et al.Review on chemical mechanical polishing of silicon wafers[J].Diamond & Abrasives Engineering,2020,238(40):24-33.(in Chinese)

    • [4] SONG X L,YANG H P,ZHANG X W,et al.Effects of H2O2 on electrochemical characteristics of silicon wafers during chemical mechanical polishing [J].Journal of the Electrochemical Society,2008,155(11):530-533.

    • [5] 林广川,郭丹,解国新,等.抛光液中离子浓度对化学机械抛光过程的影响[J].中国表面工程,2015,28(4):54-61.LIN Guangchuan,GUO Dan,XIE Guoxin,et al.Influence of ionic concentration of slurry on process of chemical mechanical polishing [J].China Surface Engineering,2015,28(4):54-61.(in Chinese)

    • [6] DANDU P R,PEETHALA B C,PENTA N K,et al.Role of amines and amino acids in enhancing the removal rates of undoped and P-doped polysilicon films during chemical mechanical polishing [J].Colloids & Surface A:Physicochemical & Engineering Aspects,2010,366(1-3):68-73.

    • [7] 杨金波,刘玉岭,刘效岩,等.pH 值调节剂对Si片 CMP 速率的影响[J].微纳电子技术,2010,47(10):643-646.YANG Jinbo,LIU Yuling,LIU Xiaoyan,et al.Effect of pH regulation on CMP rate of silicon [J].Micronanoelectronic Technology,2010,47(10):643-646.(in Chinese)

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    • [9] QIAN B,KOZHUKh J,BRUFAU T B,et al.Chemical mechanical polishing pad and method of making same [ P ].United States Patent,US9776300,2017.

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    • [14] KAWASE A,OKAMURA M,INOUE Y.Polishing composition and polishing method employing it [ P ].United States Patent,6852009,2005.

    • [15] IWATA N,NAGASHIMA I.Polishing composition for silicon wafer,polishing composition kit for silicon wafer and method of polishing silicon wafer[P].United States Patent,20090317974,2009.

    • [16] PAYNE C C.Aqueous silica compositions for polishing silicon wafers[P].United States Patent,4588421.1986.

    • [17] WEN J,MA T,ZHANG W,et al.Atomic insight into tribochemical wear mechanism of silicon at the Si/SiO2 interface in aqueous environment:Molecular dynamics simulations using ReaxFF reactive force field[J].Applied Surface Science,2016,390(30):216-223.

    • [18] WEN J,MA T,ZHANG W,et al.Atomistic mechanisms of Si chemical mechanical polishing in aqueous H2O2:ReaxFF reactive molecular dynamics simulations [J].Computational Material Science,2017,131:230-238.

    • [19] RUSSO M F,LI R,MENCH M,et al.Molecular dynamic simulation of aluminum-water reactions using the ReaxFF reactive force field[J].International Journal of Hydrogen Energy,2011,36(10):5828-5835.

    • [20] ADRI C T,DUIN V,DASGUPTA S,et al.Goddard.ReaxFF:A reactive force field for hydrocarbons[J].Journal of Physical Chemistry A,2001,105:9396-9409.

    • [21] CHENOWETH K,DUIN A,GODDARD W A.ReaxFF reactive force field for molecular dynamics simulations of hydrocarbon oxidation [J].The Journal of Physical Chemistry,2008,112(5):1040-1053.

    • [22] GROSS R,BOTT J F.Handbook of chemical lasers[M].New York:Wiley,1976.

    • [23] SEIDEL H,CSEPREGI L,HEUBERGER A,et al.Anisotropic etching of crystalline silicon in alkaline solutions I.Orientation dependence and behavior of passivation layers[J].Journal of the Electrochemical Society,1990,137(17):3612-3626.

    • [24] PIETSCH G,HIGASHI G,CHABAL Y.Chemomechanical polishing of silicon:Surface termination and mechanism of removal [J].Applied Physics Letters,1994,64(23):3115-3117.

    • [25] PIETSCH G,CHABAL Y,HIGASHI G.The atomic-scale removal mechanism during chemo-mechanical polishing of Si(100)and Si(111)[J].Surface Science,1995,331:395-401.

    • [26] LUO J,DORNFELD D A.Material removal mechanism in chemical mechanical polishing:theory and modeling[J].IEEE Transactions on Semiconductor Manufacturing,2001,14(2):112-133.

    • [27] KISHI K.Adsorption of ethylenediamine on clean and oxygen covered Fe/Ni(100)surfaces studied by XPS [J].Journal of Electron Spectroscopy Related Phenomena,1988,46(1):237-247.

    • [28] DONLEY M S,BAER D R,STOEBE T G.Nitrogen 1s charge referencing for Si3N4 and related compounds [J].Surface and Interface Analysis,1988,11(6-7):335-340.

    • [29] CHABAL Y J.Hydride formation on the Si(100):H2O surface [J].Physical Review,1984,29(6):3677-3680.

    • [30] YEON J,KIM S H,DUIN A C.Effects of water on tribochemical wear of Silicon oxide interface:Molecular dynamics(md)study with reactive force field(ReaxFF)[J].Langmuir,2016,32:1018-1026.

    • [31] LELIS S R,CALDAS M J.Ab initio study of the early stages of gas-phase water oxidation of the Si(100)(2×1):H surface[J].Physical Review B,2011,84(84):205314.

    • [32] KULKARNI A D,TRUHLAR D G,SRINIVASAN S G,et al.Oxygen interactions with Silica surfaces:Coupled cluster and density functional investigation and the development of a new ReaxFF potential[J].Journal of Physical Chemistry C,2013,117(1):258-269.

  • 基本信息

    中图分类号: TH117
    DOI: 10.11933/j.issn.1007-9289.20210413002

    基金信息

    安徽省高校自然科学基金(KJ2020A0091)；
    电子信息系统仿真设计安徽省重点实验室开放课题(2019ZDSYSZB02)；
    安徽省高校优秀人才支持计划(gxyq2020042)资助项目；
    Supported by Natural Science Foundation of Anhui High Education(KJ2020A0091)；
    Opening Foundation of Anhui Province Key Laboratory of Simulation and Design for Electronic Information System (2019ZDSYSZB02)；
    Project of Excellent Talents Support Plan in Colleges of Anhui Province(gxyq2020042).；

    引用信息

    稿件历史

    收稿日期: 2021-04-13

  • 参考文献

    • [1] LIU Y L,ZHANG K L,WANG F,et al.Investigation on the final polishing slurry and technique of silicon substrate in ULSI [J].Microelectronic,Engineering,2003,66(1/4):438-444.

    • [2] KIM S K,KIM Y H,PAIK U,et al.The Effect of the physicochemical properties of cellulosic polymers on the Si wafer polishing process[J].Journal of Electroceramics,2006,17(2-4):835-839.

    • [3] 徐嘉慧,康仁科,董志刚,等.硅片化学机械抛光技术的研究进展[J].金刚石与磨料磨具工程,2020,238(40):24-33.XU Jiahui,KANG Renke,DONG Zhigang,et al.Review on chemical mechanical polishing of silicon wafers[J].Diamond & Abrasives Engineering,2020,238(40):24-33.(in Chinese)

    • [4] SONG X L,YANG H P,ZHANG X W,et al.Effects of H2O2 on electrochemical characteristics of silicon wafers during chemical mechanical polishing [J].Journal of the Electrochemical Society,2008,155(11):530-533.

    • [5] 林广川,郭丹,解国新,等.抛光液中离子浓度对化学机械抛光过程的影响[J].中国表面工程,2015,28(4):54-61.LIN Guangchuan,GUO Dan,XIE Guoxin,et al.Influence of ionic concentration of slurry on process of chemical mechanical polishing [J].China Surface Engineering,2015,28(4):54-61.(in Chinese)

    • [6] DANDU P R,PEETHALA B C,PENTA N K,et al.Role of amines and amino acids in enhancing the removal rates of undoped and P-doped polysilicon films during chemical mechanical polishing [J].Colloids & Surface A:Physicochemical & Engineering Aspects,2010,366(1-3):68-73.

    • [7] 杨金波,刘玉岭,刘效岩,等.pH 值调节剂对Si片 CMP 速率的影响[J].微纳电子技术,2010,47(10):643-646.YANG Jinbo,LIU Yuling,LIU Xiaoyan,et al.Effect of pH regulation on CMP rate of silicon [J].Micronanoelectronic Technology,2010,47(10):643-646.(in Chinese)

    • [8] 左海珍.一种高稳定高效抛光液及其制备方法和应用[ P].中国发明专利,CN109971362A.2019.ZUO Haizhen.A high stability and high efficiency polishing liquid and its preparation method and application[ P].Chinese Patent,CN109971362A,2019.(in Chinese)

    • [9] QIAN B,KOZHUKh J,BRUFAU T B,et al.Chemical mechanical polishing pad and method of making same [ P ].United States Patent,US9776300,2017.

    • [10] PAYNE CHARLES C.Silica sol compositions for polishing silicon wafers[P].United States Patent,4462188,1984.

    • [11] CUI H,PARK J G,PARK J,et al.Reduction of metal contaminants level on the silicon wafer surface using chemical additive during chemical mechanical polishing [ C ]//ECS Meeting,Orlando,2014.

    • [12] ROH H S,PARK T W,LEE T Y,et al.Polishing slurry composition for improving surface quality of silicon wafer and method for polishing silicon wafer using the same [ P ].WO Patent,EP1856224,2011.

    • [13] LONCKI S B,COOK L,SHEN J,et al.Polishing silicon wafers with improved polishing slurries [ P ].United States Patent,5860848,1999.

    • [14] KAWASE A,OKAMURA M,INOUE Y.Polishing composition and polishing method employing it [ P ].United States Patent,6852009,2005.

    • [15] IWATA N,NAGASHIMA I.Polishing composition for silicon wafer,polishing composition kit for silicon wafer and method of polishing silicon wafer[P].United States Patent,20090317974,2009.

    • [16] PAYNE C C.Aqueous silica compositions for polishing silicon wafers[P].United States Patent,4588421.1986.

    • [17] WEN J,MA T,ZHANG W,et al.Atomic insight into tribochemical wear mechanism of silicon at the Si/SiO2 interface in aqueous environment:Molecular dynamics simulations using ReaxFF reactive force field[J].Applied Surface Science,2016,390(30):216-223.

    • [18] WEN J,MA T,ZHANG W,et al.Atomistic mechanisms of Si chemical mechanical polishing in aqueous H2O2:ReaxFF reactive molecular dynamics simulations [J].Computational Material Science,2017,131:230-238.

    • [19] RUSSO M F,LI R,MENCH M,et al.Molecular dynamic simulation of aluminum-water reactions using the ReaxFF reactive force field[J].International Journal of Hydrogen Energy,2011,36(10):5828-5835.

    • [20] ADRI C T,DUIN V,DASGUPTA S,et al.Goddard.ReaxFF:A reactive force field for hydrocarbons[J].Journal of Physical Chemistry A,2001,105:9396-9409.

    • [21] CHENOWETH K,DUIN A,GODDARD W A.ReaxFF reactive force field for molecular dynamics simulations of hydrocarbon oxidation [J].The Journal of Physical Chemistry,2008,112(5):1040-1053.

    • [22] GROSS R,BOTT J F.Handbook of chemical lasers[M].New York:Wiley,1976.

    • [23] SEIDEL H,CSEPREGI L,HEUBERGER A,et al.Anisotropic etching of crystalline silicon in alkaline solutions I.Orientation dependence and behavior of passivation layers[J].Journal of the Electrochemical Society,1990,137(17):3612-3626.

    • [24] PIETSCH G,HIGASHI G,CHABAL Y.Chemomechanical polishing of silicon:Surface termination and mechanism of removal [J].Applied Physics Letters,1994,64(23):3115-3117.

    • [25] PIETSCH G,CHABAL Y,HIGASHI G.The atomic-scale removal mechanism during chemo-mechanical polishing of Si(100)and Si(111)[J].Surface Science,1995,331:395-401.

    • [26] LUO J,DORNFELD D A.Material removal mechanism in chemical mechanical polishing:theory and modeling[J].IEEE Transactions on Semiconductor Manufacturing,2001,14(2):112-133.

    • [27] KISHI K.Adsorption of ethylenediamine on clean and oxygen covered Fe/Ni(100)surfaces studied by XPS [J].Journal of Electron Spectroscopy Related Phenomena,1988,46(1):237-247.

    • [28] DONLEY M S,BAER D R,STOEBE T G.Nitrogen 1s charge referencing for Si3N4 and related compounds [J].Surface and Interface Analysis,1988,11(6-7):335-340.

    • [29] CHABAL Y J.Hydride formation on the Si(100):H2O surface [J].Physical Review,1984,29(6):3677-3680.

    • [30] YEON J,KIM S H,DUIN A C.Effects of water on tribochemical wear of Silicon oxide interface:Molecular dynamics(md)study with reactive force field(ReaxFF)[J].Langmuir,2016,32:1018-1026.

    • [31] LELIS S R,CALDAS M J.Ab initio study of the early stages of gas-phase water oxidation of the Si(100)(2×1):H surface[J].Physical Review B,2011,84(84):205314.

    • [32] KULKARNI A D,TRUHLAR D G,SRINIVASAN S G,et al.Oxygen interactions with Silica surfaces:Coupled cluster and density functional investigation and the development of a new ReaxFF potential[J].Journal of Physical Chemistry C,2013,117(1):258-269.

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