王书鹏,薛彦鹏,范磊,潘盈卓,程洁,崔碧佳.健那绿B平整剂对芯片互连钴的电沉积成核机理研究[J].表面技术,2024,53(24):178-187.
WANG Shupeng,XUE Yanpeng,FAN Lei,PAN Yingzhuo,CHENG Jie,CUI Bijia.Effects of Janus Green B Leveler on Nucleation Mechanism of Cobalt Electrodeposition in Chip Interconnection[J].Surface Technology,2024,53(24):178-187 |
| 健那绿B平整剂对芯片互连钴的电沉积成核机理研究 |
| Effects of Janus Green B Leveler on Nucleation Mechanism of Cobalt Electrodeposition in Chip Interconnection |
| 投稿时间：2024-01-11 修订日期：2024-03-15 |
| DOI：10.16490/j.cnki.issn.1001-3660.2024.24.016 |
| 中文关键词: 钴 电子电镀 互连金属 集成电路 平整剂 薄膜技术 |
| 英文关键词:cobalt (Co) electronic electroplating interconnection metal integrated circuit (IC) leveler thin-film technology |
| 基金项目:国家自然科学基金(52075037);北京市自然科学基金(3222017);清华大学高端装备界面科学与技术全国重点实验室开放基金(SKLTKF21A01) |
|
|
| Author | Institution |
| WANG Shupeng | School of Mechanical and Electrical Engineering, China University of Mining & Technology Beijing, Beijing 100083, China |
| XUE Yanpeng | National Center for Materials Service Safety, University of Science and Technology Beijing, Beijing 100083, China |
| FAN Lei | School of Mechanical and Electrical Engineering, China University of Mining & Technology Beijing, Beijing 100083, China |
| PAN Yingzhuo | School of Mechanical and Electrical Engineering, China University of Mining & Technology Beijing, Beijing 100083, China |
| CHENG Jie | School of Mechanical and Electrical Engineering, China University of Mining & Technology Beijing, Beijing 100083, China |
| CUI Bijia | School of Mechanical and Electrical Engineering, China University of Mining & Technology Beijing, Beijing 100083, China |
|
| 摘要点击次数: |
| 全文下载次数: |
| 中文摘要: |
| 目的 探究了钴互连金属电子电镀工艺中的电镀成核机理，使用健那绿B(Janus Green B，JGB)对钴的电沉积进行进一步优化，并研究了JGB在改善电镀质量过程中的作用机理。方法 采用电化学测试方法包括循环伏安、电流瞬态曲线，以及表征方法包括扫描电子显微镜(SEM)以及X射线衍射光谱(XRD)，对钴在阻挡层TiN上的电子电镀机理以及JGB作用下的成核特点及晶体特性等进行研究。结果 测试得到了关于体系的电化学曲线以及薄膜微观表征图样，发现了JGB的成核特征，并在无金属阳离子的体系下进行对照实验，进而得出JGB对钴电沉积体系的影响机理。结论 JGB促进了体系氢还原的进行，并改变了钴的成核特征，包括成核大小和数目，进而提升了电沉积质量，实现了更高的薄膜沉积覆盖率。JGB在体系中发生一系列电化学反应生成产物γ，产物γ由于带有不饱和N原子(显正电)，会优先吸附到阴极的凸起处，γ分子剩余C—H—N结构可以抑制新的钴原子成核，从而增强电极表面还原沉积的平整度，使晶粒生长更加均匀。 |
| 英文摘要: |
| As the technology node of integrated circuit (IC) progressively shrinks, the critical dimension approaches the physical extremes of the interconnect metals. This trend is accompanied by a set of increasingly severe issues, notably the RC delay stemming from copper (Cu) interconnects. Cobalt (Co) emerges as a competitive alternative for Cu for the sub-10 nm nodes, and it is expected to replace Cu as new interconnect metal. This study explored the nucleation mechanism during the Co electronic electroplating process on a TiN surface. Janus Green B (JGB), a leveler commonly used in the Cu electroplating process, was used to improve the film quality during the Co electroplating. Multiple methods such as the electrochemical cyclic voltammetry and current transient analysis, together with the scanning electron microscopy (SEM) and X-ray diffraction (XRD) characterization were applied to fully reveal the nucleation mechanism during the Co electroplating. Cyclic voltammetry curves were used to determine the reaction composition of the system as well as the appropriate reduction potential. Transient currents were utilized to evaluate the extent of the electrode reaction, and the Volmer-Weber3D method was used to back-convolute the transient current curves to predict the form of Co reduction nucleation at the electrode surface. SEM was used to observe the microstructure of the film layer to evaluate the filling uniformity and gaplessness of the substrate. XRD was used to characterize the crystal information related to the surface of the film layer. Results showed that in the JGB-free accession system, the nucleation mode was dominated by instantaneous nucleation, supplemented by progressive nucleation. At more positive potentials, a part of progressive nucleation was slightly increased, but still dominated by instantaneous nucleation. The introduction of JGB promoted the hydrogen precipitation reaction of the system and changed the nucleation characteristics, including the size and number of nuclei, which lead to the improvement of the electrodeposition quality and the realization of higher coverage of thin film deposition. JGB with the proton together with the diffusion of the cathode surface of the combination of the electron break N==N double bond got product α. Product α and the two protons continued to occur electrode reaction to get product β and product γ. Product γ due to the unsaturated N atoms (positively charged), would be preferentially adsorbed to the tip of the cathode or the protruding place, γ molecule residual C—H—N structure could hinder the new Co atoms nucleation at the point of its adhesion, which could hinder the nucleation of new Co atoms at their attachment sites, thus enhancing the flatness of the reduced deposition on the electrode surface and making the grain growth more uniform. This uniform growth was reflected in the increase of grain size on the one hand, and on the other hand, a uniform grain structure was produced, which lead to the increase of substrate coverage and the grain boundaries were no longer obvious, and the quality of the metal electrodeposited films was improved. The adsorption of the product γ ended with the disappearance of the tip on the electrode surface. The electrode surface without added JGB remained tip-retained point active, exacerbating the inhomogeneity of the film layer. The research results are of great theoretical value for the development of a new process of ultra-smooth and defectless plating of Co interconnect metals at nodes of integrated circuits below 10 nm. |
| 查看全文 查看/发表评论 下载PDF阅读器 |
| 关闭 |
|
|
|
渝公网安备 50010702501715号