Abstract
Chemical mechanical planarization (CMP) is an important operation for surface modification of wafers in semiconductor manufacturing. Productivity and quality of wafers depends strongly on the efficiency of CMP and virtual metrology (VM) is a promising tool not only to facilitate wafer-to-wafer control but also to reduce cycle time. Development of VM tools for CMP is still not a reality due to the complexity of CMP and unavailability of critical process measurements such as slurry temperature and abrasive particle size distribution in real-time. To overcome these challenges, a novel hybrid modeling framework is proposed for creating a VM solution for CMP. Physics-based models are utilized for estimating slurry temperature and mean abrasive particle size (MAPS) from sensor data. They supplement other sensor data for developing soft sensors to predict slurry temperature, MAPS, and the material removal rate (MRR). This hybrid framework is tested with about 3000 sets of published industrial sensor data. Exploratory analysis indicated two distinct regimes of operation, low and high MRR, and a strong relationship of MRR with slurry temperature and MAPS. Several machine learning (ML) algorithms such as random forest, Lasso regression and support vector machine are explored and XGBoost is found to be the best amongst them. The optimum operating conditions are determined through model-based optimization using the hybrid modeling framework and particle swarm optimization. These results suggested CMP to be carried out at the smallest MAPS to maximize MRR. This framework would be useful for building a digital twin system of CMP.
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Data availability
The raw data of the CMP process used for analysis, model development and process optimization are provided by the PHM data challenge, 2016 (PHM Society, 2016). This data is in public domain (PHM Society, 2016). The preprocessed or the clean data is available with the authors and can be made available to the requestor based on qualified request.
Abbreviations
- abs max :
-
Maximum value of particle size (µm)
- abs min :
-
Minimum value of particle size (µm)
- abs n :
-
Normalized MAPS
- AI:
-
Artificial intelligence
- AUC:
-
Area under curve
- BEOL:
-
Back end of line
- CFD:
-
Computational fluid dynamics
- CLC:
-
Closed loop control
- d j :
-
Disturbance variable
- DBN:
-
Deep belief networks
- DDMs:
-
Data driven models
- DEM:
-
Discrete element method
- E comb :
-
Combined activation energy (J/mol)
- ERT:
-
Extremely Randomized trees
- f :
-
Function of decision/disturbance variable
- FEOL:
-
Front end of line
- GBT:
-
Gradient boosting trees
- IMM:
-
Integrated metrology module
- k :
-
Thermal independent constant
- KNN:
-
K-nearest neighbors
- KPI:
-
Key performance indicators
- L2L:
-
Lot to lot
- l i :
-
Lower bounds of decision variable
- LSTM:
-
Long short-term memory
- MAE:
-
Mean absolute error
- MAPS:
-
Mean absolute particle size
- ML:
-
Machine learning
- MRR:
-
Material removal rate
- MSE:
-
Mean square error
- MTGP:
-
Multi task gaussian process
- n i :
-
Number of feature selection methods that selected ith feature
- P :
-
Pressure applied on the wafer (Pa)
- PBMs:
-
Physics based models
- PSO:
-
Particle swarm optimization
- R :
-
Universal gas constant (J/mol. K)
- R2 :
-
Coefficient of regression
- R i ,k :
-
Rank of the feature i
- RMSE:
-
Root means square error
- SAM:
-
Stand-alone metrology module
- SVM:
-
Support vector machines
- t :
-
Number of dimensional spaces
- T :
-
Slurry temperature (K)
- T max :
-
Maximum temperature (K)
- T min :
-
Minimum temperature (K)
- T n :
-
Normalized temperature
- u i :
-
Upper bounds of decision variable
- U :
-
Relative velocity (m/s)
- v j :
-
Velocity of the particle
- VM:
-
Virtual metrology
- W2W:
-
Wafer to wafer
- x i :
-
Decision variable
- x j :
-
Position of the particle
References
Balan, V., Seignard, A., Scevola, D., Lugand, J. F., Di Cioccio, L., & Rivoire, M. (2012). CMP Process Optimization for Bonding Applications. In ICPT 2012 - International Conference on Planarization/CMP Technology, 1–7.
Bao, H., Chen, L., & Ren, B. (2020). A study on the pattern effects of chemical mechanical planarization with CNN-based models. Electronics (switzerland), 9(7), 1–16. https://doi.org/10.3390/electronics9071158
Bielmann, M., Mahajan, U., & Singh, R. K. (1999). Effect of particle size during tungsten chemical mechanical polishing. Electrochemical and Solid-State Letters, 2(8), 401–403. https://doi.org/10.1149/1.1390851
Biswas, J., Kumar, R., Mynam, M., Nistala, S., Panda, A., Pandya, R., Rathore, R., & Runkana, V., (2018). Method and System for Data Based Optimization of Performance Indicators in Process and Manufacturing Industries. (US Patent No. US10636007B2). U.S. Patent and Trade-mark Office. https://image-ppubs.uspto.gov/dirsearch-public/print/downloadPdf/10636007
Blank, J., & Deb, K. (2020). Pymoo: Multi-objective optimization in python. IEEE Access, 8, 89497–89509. https://doi.org/10.1109/ACCESS.2020.2990567
Bulsara, V. H., Ahn, Y., Chandrasekar, S., & Farris, T. N. (1997). Polishing and lapping temperatures. Journal of Tribology, 119(1), 163–170. https://doi.org/10.1115/1.2832453
Cai, H., Feng, J., Yang, Q., Li, W., Li, X., & Lee, J. (2020). A virtual metrology method with prediction uncertainty based on Gaussian process for chemical mechanical planarization. Computers in Industry. https://doi.org/10.1016/j.compind.2020.103228
Chandra, A., Karra, P., Bastawros, A. F., Biswas, R., Sherman, P. J., Armini, S., & Lucca, D. A. (2008). Prediction of scratch generation in chemical mechanical planarization. CIRP Annals, 57(1), 559–562. https://doi.org/10.1016/j.cirp.2008.03.130
Chen, P. H., Wu, S., Lin, J., Ko, F., Lo, H., Wang, J., Yu, C. H., & Liang, M. S. (2005). Virtual metrology: A solution for wafer to wafer advanced process control. ISSM 2005. IEEE International Symposium on Semiconductor Manufacturing, 2005, 155–157. https://doi.org/10.1109/issm.2005.1513322
Chen, T., & Guestrin, C. (2016, August). Xgboost: A scalable tree boosting system. In Proceedings of the 22nd acm sigkdd international conference on knowledge discovery and data mining, pp 785–794. https://doi.org/10.1145/2939672.2939785
Fan, S. K. S., & Chang, Y. J. (2013). An integrated advanced process control framework using run-to-run control, virtual metrology and fault detection. Journal of Process Control, 23(7), 933–942. https://doi.org/10.1016/j.jprocont.2013.03.013
Grubbs, F. E. (1969). Procedures for detecting outlying observations in samples. Technometrics, 11(1), 1–21. https://doi.org/10.1080/00401706.1969.10490657
Guo, D., Liu, J., Kang, R., & Jin, Z. (2007). A pad roughness model for the analysis of lubrication in the chemical mechanical polishing of a silicon wafer. Semiconductor Science and Technology, 22(7), 793–797. https://doi.org/10.1088/0268-1242/22/7/020
Harris, C. R., Millman, K. J., Van Der Walt, S. J., Gommers, R., Virtanen, P., Cournapeau, D., Wieser, E., Taylor, J., Berg, S., Smith, N. J., & Kern, R. (2020). Array programming with NumPy. Nature, 585(7825), 357–362. https://doi.org/10.1038/s41586-020-2649-2
Hunter, J. D. (2007). Matplotlib: A 2D graphics environment. Computing in Science and Engineering, 9(03), 90–95. https://doi.org/10.1109/MCSE.2007.55
Jabri, K., Dumur, D., Godoy, E., Mouchette, A., & Bèle, B. (2011). Particle swarm optimization based tuning of a modified smith predictor for mould level control in continuous casting. Journal of Process Control, 21(2), 263–270. https://doi.org/10.1016/j.jprocont.2010.10.019
Jebri, M. A., El Adel, E. M., Graton, G., Ouladsine, M., & Pinaton, J. (2017). The impact of the virtual metrology on a run-to-run control for a chemical mechanical planarization process. IFAC-PapersOnLine, 50(1), 6154–6159. https://doi.org/10.1016/j.ifacol.2017.08.980
Jia, X., Di, Y., Feng, J., Yang, Q., Dai, H., & Lee, J. (2018). Adaptive virtual metrology for semiconductor chemical mechanical planarization process using GMDH-type polynomial neural networks. Journal of Process Control, 62, 44–54. https://doi.org/10.1016/j.jprocont.2017.12.004
Karra, P. K. (2009). Modeling and control of material removal and defectivity in chemical mechanical planarization. (Doctoral dissertation, Iowa state university). https://doi.org/10.31274/etd-180810-313
Kennedy, J., & Eberhart, R. (1995). Particle swarm optimization. In Proceedings of ICNN’95—International Conference on Neural Networks, 4, 1942–1948. https://doi.org/10.1109/ICNN.1995.488968
Khan, A. A., Moyne, J. R., & Tilbury, D. M. (2008). Virtual metrology and feedback control for semiconductor manufacturing processes using recursive partial least squares. Journal of Process Control, 18(10), 961–974. https://doi.org/10.1016/j.jprocont.2008.04.014
Kong, Z., Oztekin, A., Beyca, O. F., Phatak, U., Bukkapatnam, S. T. S., & Komanduri, R. (2010). Process performance prediction for chemical mechanical planarization (CMP) by integration of nonlinear bayesian analysis and statistical modeling. IEEE Transactions on Semiconductor Manufacturing, 23(2), 316–327. https://doi.org/10.1109/TSM.2010.2046110
Krishnan, M., Nalaskowski, J. W., & Cook, L. M. (2010). Chemical mechanical planarization: Slurry chemistry, materials, and mechanisms. Chemical Reviews, 110(1), 178–204. https://doi.org/10.1021/cr900170z
Lee, K. B., & Kim, C. O. (2020). Recurrent feature-incorporated convolutional neural network for virtual metrology of the chemical mechanical planarization process. Journal of Intelligent Manufacturing, 31(1), 73–86. https://doi.org/10.1007/s10845-018-1437-4
Lee, J., Kao, H. A., & Yang, S. (2014). Service innovation and smart analytics for Industry 4.0 and big data environment. In Procedia CIRP, 16, 3–8. https://doi.org/10.1016/j.procir.2014.02.001
Li, Z., Wu, D., & Yu, T. (2019). Prediction of material removal rate for chemical mechanical planarization using decision tree-based ensemble learning. Journal of Manufacturing Science and Engineering, Transactions of the ASME, DOI, 10(1115/1), 4042051.
Li, X., Wang, C., Zhang, L., Mo, X., Zhao, D., & Li, C. (2018, March). Assessment of physics-based and data-driven models for material removal rate prediction in chemical mechanical polishing. In 2018 2nd International Conference on Electrical Engineering and Automation (ICEEA 2018), 116–121. https://doi.org/10.2991/iceea-18.2018.26
Liu, J., Liu, T., Chen, J., Yue, H., Zhang, F., & Sun, F. (2020). Data-driven modeling of product crystal size distribution and optimal input design for batch cooling crystallization processes. Journal of Process Control, 96, 1–14. https://doi.org/10.1016/j.jprocont.2020.10.003
Luo, J., & Dornfeld, D. A. (2001). Material removal mechanism in chemical mechanical polishing: Theory and modeling. IEEE Transactions on Semiconductor Manufacturing, 14(2), 112–133. https://doi.org/10.1109/66.920723
Luo, J., & Dornfeld, D. A. (2003). Effects of abrasive size distribution in chemical mechanical planarization: Modeling and verification. IEEE Transactions on Semiconductor Manufacturing, 16(3), 469–476. https://doi.org/10.1109/TSM.2003.815199
Maggipinto, M., Beghi, A., McLoone, S., & Susto, G. A. (2019). DeepVM: A deep learning-based approach with automatic feature extraction for 2D input data virtual metrology. Journal of Process Control, 84, 24–34. https://doi.org/10.1016/j.jprocont.2019.08.006
Pak, K., Park, Y. R., Chung, U. I., Koh, Y. B., & Lee, M. Y. (1997). A CMP process using a fast oxide slurry. In Proceedings of the Second International Chemical Mechanical Planarization for ULSI Multilevel Interconnection Conference, 299–306.
Paul, E., Kaufman, F., Brusic, V., Zhang, J., Sun, F., & Vacassy, R. (2005). A model of copper CMP. Journal of the Electrochemical Society, 152(4), G322. https://doi.org/10.1149/1.1861175
Pedregosa, F., Varoquaux, G., Gramfort, A., Michel, V., Thirion, B., Grisel, O., Blondel, M., Prettenhofer, P., Weiss, R., & Dubourg, V. (2011). Scikit-learn: machine learning in Python. Journal of Machine Learning Research, 12, 2825–2830.
PHM Society. (2016, September). PHM Data Challenge 2016. https://phmsociety.org/conference/annual-conference-of-the-phm-society/annual-conference-of-the-prognostics-and-health-management-society-2016/phm-data-challenge-4/
Preston, F. W. (1927). The theory and design of plate glass polishing machines. Journal Society of Glass Technology, 11, 214.
Rao, P. K., Bhushan, M. B., Bukkapatnam, S. T. S., Kong, Z., Byalal, S., & Beyca, O. F. (2014). Process-machine interaction (PMI) modeling and monitoring of chemical mechanical planarization (CMP) process using wireless vibration sensors. IEEE Transactions on Semiconductor Manufacturing, 27(1), 1–15. https://doi.org/10.1109/TSM.2013.2293095
Shen, H. (2014). Interactive notebooks: Sharing the code. Nature, 515(7525), 152–152. https://doi.org/10.1038/515151a
Shih, S. Y., & Chen, L. J. (1998). Thermal characteristics study of CMP low dielectric constant material. In Proc. Third International Chemical-Mechanical Planarization for ULSI Multilevel Interconnection Conference, 19.
Singh, K., Selvanathan, B., Zope, K., Nistala, S. H., & Runkana, V. (2018). Concurrent Estimation of Remaining Useful Life for Multiple Faults in an Ion Etch Mill. Annual Conference of the PHM Society, 10.
Sorooshian, J., DeNardis, D., Charns, L., Li, Z., Shadman, F., Boning, D., Hetherington, D., & Philipossian, A. (2004). Arrhenius Characterization of ILD and Copper CMP Processes. Journal of the Electrochemical Society, 151(2), G85. https://doi.org/10.1149/1.1635388
Sun, Y., Qin, W., Zhuang, Z., & Xu, H. (2021). An adaptive fault detection and root-cause analysis scheme for complex industrial processes using moving window KPCA and information geometric causal inference. Journal of Intelligent Manufacturing, 32(7), 2007–2021. https://doi.org/10.1007/s10845-021-01752-9
Susto, G. A., Schirru, A., Pampuri, S., Beghi, A., & De Nicolao, G. (2018). A hidden-Gamma model-based filtering and prediction approach for monotonic health factors in manufacturing. Control Engineering Practice, 74, 84–94. https://doi.org/10.1016/j.conengprac.2018.02.011
Suthar, K., Shah, D., Wang, J., & He, Q. P. (2019). Next-generation virtual metrology for semiconductor manufacturing: A feature-based framework. Computers and Chemical Engineering, 127, 140–149. https://doi.org/10.1016/j.compchemeng.2019.05.016
The Pandas Development Team. (2023). Pandas-dev/pandas: Pandas (v2.1.0). Zenodo. https://doi.org/10.5281/zenodo.8301632
Virtanen, P., Gommers, R., Oliphant, T. E., Haberland, M., Reddy, T., Cournapeau, D., & Van Mulbregt, P. (2020). SciPy 1.0: fundamental algorithms for scientific computing in Python. Nature Methods, 17(3), 261–272. https://doi.org/10.1038/s41592-019-0686-2
Wang, G. J., & Chou, M. H. (2005). A neural-Taguchi-based quasi time-optimization control strategy for chemical-mechanical polishing processes. International Journal of Advanced Manufacturing Technology, 26(7–8), 759–765. https://doi.org/10.1007/s00170-003-1859-8
Wang, Y., Chen, Y., Qi, F., Zhao, D., & Liu, W. (2016). A material removal model for silicon oxide layers in chemical mechanical planarization considering the promoted chemical reaction by the down pressure. Tribology International, 93, 11–16. https://doi.org/10.1016/j.triboint.2015.09.008
Wang, P., Gao, R. X., & Yan, R. (2017). A deep learning-based approach to material removal rate prediction in polishing. CIRP Annals - Manufacturing Technology, 66(1), 429–432. https://doi.org/10.1016/j.cirp.2017.04.013
Warnock, J. (1991). A two-dimensional process model for chemimechanical polish planarization. Journal of the Electrochemical Society, 138(8), 2398–2402. https://doi.org/10.1149/1.2085984
Waskom, M. L. (2021). Seaborn: statistical data visualization. Journal of Open Source Software, 6(60), 3021. https://doi.org/10.21105/joss.03021
White, D., Melvin, J., & Boning, D. (2003). Characterization and modeling of dynamic thermal behavior in CMP. Journal of the Electrochemical Society, 150(4), G271. https://doi.org/10.1149/1.1560642
Wu, D., Jennings, C., Terpenny, J., Gao, R. X., & Kumara, S. (2017). A comparative study on machine learning algorithms for smart manufacturing: tool wear prediction using random forests. Journal of Manufacturing Science and Engineering, Transactions of the ASME, 139(7), 1–9. https://doi.org/10.1115/1.4036350
Xu, Q., Chen, L., Fang, J., & Yang, F. (2015). Microelectronic Engineering A chemical mechanical planarization model for aluminum gate structures. Microelectronic Engineering, 131, 58–67. https://doi.org/10.1016/j.mee.2014.09.023
Yu, T., Li, Z., & Wu, D. (2019). Predictive modeling of material removal rate in chemical mechanical planarization with physics-informed machine learning. Wear, 426–427(February), 1430–1438. https://doi.org/10.1016/j.wear.2019.02.012
Yu, H. M., Lin, C. C., Hsu, M. H., Chen, Y. T., Chen, K. W., Luoh, T., Yang, L., Yang, T., & Chen, K. C. (2021). CMP process optimization engineering by machine learning. IEEE Transactions on Semiconductor Manufacturing, 34(3), 280–285. https://doi.org/10.1109/TSM.2021.3072361
Zhao, S., & Huang, Y. (2018). A stack fusion model for material removal rate prediction in chemical-mechanical planarization process. International Journal of Advanced Manufacturing Technology, 99(9–12), 2407–2416. https://doi.org/10.1007/s00170-018-2578-5
Acknowledgements
The authors thank the management of Tata Consultancy Services for the permission to publish this paper, and Mr. K. Ananth Krishnan, Dr. Harrick Vin and Dr. Gautam Shroff for their encouragement and support.
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This study was funded by the Tata Consultancy Services Limited.
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Conceptualization: NKVN, VR; Data curation: BD; Formal Analysis and Investigation: BD, VSM; Methodology: VSM, NKVN; Supervision: VR; Validation: BD, VSM; Visualization: BD, VSM; Writing – original draft: BD; Writing – review & editing: VSM, NKVN, VR.
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Deivendran, B., Masampally, V.S., Nadimpalli, N.R.V. et al. Virtual metrology for chemical mechanical planarization of semiconductor wafers. J Intell Manuf (2024). https://doi.org/10.1007/s10845-024-02335-0
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DOI: https://doi.org/10.1007/s10845-024-02335-0