The influence of abrasive size on high-pressure chemical mechanical polishing of sapphire wafer
International Journal of Precision Engineering and Manufacturing-Green Technology - Tập 2 - Trang 157-162 - 2015
Tóm tắt
Demand for sapphire wafer has increased with growth of LED market. Chemical mechanical polishing (CMP) comprises a large part of wafering cost since the CMP process requires approximately 3–6 hours. For longer polishing times, the cost of consumables (COC) in CMP increases the total wafering cost; hence, considerable efforts have been made to decrease the polishing time of sapphire wafers to reduce the COC. There are two main approaches to reduce polishing time: controlling the chemical factor and adjusting the mechanical factor. Controlling the chemical factor is a common approach to manipulating the removal rate and roughness. However, it is hard to control the chemical factor. Instead, this study investigates the effects of various mechanical factors. This paper focuses on the effect of high-pressure CMP on the material removal performance; the maximum applied pressure is ∼800 g/cm2. The removal rate increases linearly with gradual increase of CMP pressure to 800 g/cm2. Finally, the effect of high pressure on the removal rate of, and frictional force on, sapphire wafer during CMP using different sized abrasives is investigated; the effect of the abrasives on the removal rate is likewise analyzed at different pressures.
Tài liệu tham khảo
Niu, X.-H., Liu, Y.-L., Tan, B.-M., Han, L.-Y., and Zhang, J.-X., “Method of Surface Treatment on Sapphire Substrate,” Transactions of Nonferrous Metals Society of China, Vol. 16, pp. s732–s734, 2006.
Lee, Y.-J., Lin, P.-C., Lu, T.-C., Kuo, H.-C., and Wang, S., “Dichromatic Ingan-Based White Light Emitting Diodes by Using Laser Lift-Off and Wafer-Bonding Schemes,” Applied Physics Letters, Vol. 90, No. 16, Paper No. 161115, 2007.
Cabalu, J., Bhattacharyya, A., Thomidis, C., Friel, I., Moustakas, T., et al., “High Power Ultraviolet Light Emitting Diodes based on GaN AlGaN Quantum Wells Produced by Molecular Beam Epitaxy,” Journal of Applied Physics, Vol. 100, No. 10, Paper No. 104506, 2006.
Hu, X., Song, Z., Pan, Z., Liu, W., and Wu, L., “Planarization Machining of Sapphire Wafers with Boron Carbide and Colloidal Silica as Abrasives,” Applied Surface Science, Vol. 255, No. 19, pp. 8230–8234, 2009.
Murata, J., Kubota, A., Yagi, K., Sano, Y., Hara, H., et al., “Chemical Planarization of Gan using Hydroxyl Radicals Generated on a Catalyst Plate in H2O2 Solution,” Journal of Crystal Growth, Vol. 310, No. 7, pp. 1637–1641, 2008.
An, J. H., Lee, G. S., Lee, W. J., Shin, B. C., Seo, J. D., et al., “Effect of Process Parameters on Material Removal Rate in Chemical Mechanical Polishing of 6H-SiC (0001),” Proc. of the Materials Science Forum, pp. 831–834, 2009.
Zhu, H., Tessaroto, L. A., Sabia, R., Greenhut, V. A., Smith, M., et al., “Chemical Mechanical Polishing (CMP) Anisotropy in Sapphire,” Applied Surface Science, Vol. 236, No. 1, pp. 120–130, 2004.
Lu, Z., Lee, S.-H., Babu, S., and Matijeviæ, E., “The Use of Monodispersed Colloids in the Polishing of Copper and Tantalum,” Journal of Colloid and Interface Science, Vol. 261, No. 1, pp. 55–64, 2003.
Lee, J.-T., Won, J.-K., and Lee, E.-S., “A Study on the Characteristics of a Wafer-Polishing Process according to Machining Conditions,” Int. J. Precis. Eng. Manuf., Vo. 10, No. 1, pp. 23–28, 2009.
Budnikov, À., Vovk, Å., Krivonogov, S., Danko, À. Y., and Lukiyenko, Î., “Anisotropy of Sapphire Properties Associated with Chemical Mechanical Polishing with Silica,” Functional Materials, Vol. 17, No. 4, pp. 489, 2010.
Fu, G., Chandra, A., Guha, S., and Subhash, G., “A Plasticity-Based Model of Material Removal in Chemical-Mechanical Polishing (CMP),” IEEE Transactions on Semiconductor Manufacturing, Vol. 14, No. 4, pp. 406–417, 2001.
Ahmadi, G. and Xia, X., “A Model for Mechanical Wear and Abrasive Particle Adhesion during the Chemical Mechanical Polishing Process,” Journal of the Electrochemical Society, Vol. 148, No. 3, pp. G99–G109, 2001.
Bielmann, M., Mahajan, U., and Singh, R. K., “Effect of Particle Size during Tungsten Chemical Mechanical Polishing,” Electrochemical and Solid-State Letters, Vol. 2, No. 8, pp. 401–403, 1999.
Tseng, W.-T., Wang, Y.-L., and Niu, J., “Microstructure-Related Resistivity Change after Chemical-Mechanical Polish of Al and W Thin Films,” Thin Solid Films, Vol. 370, No. 1, pp. 96–100, 2000.
Lee, H. and Jeong, H., “Analysis of Removal Mechanism on Oxide CMP using Mixed Abrasive Slurry,” Int. J. Precis. Eng. Manuf., Vol. 16, No. 3, pp. 603–607, 2015.
Yebing, T., Zhaowei, Z., and Jun, H. N., “Effects of Chemical Slurries on Fixed Abrasive Chemical-Mechanical Polishing of Optical Silicon Substrates,” Int. J. Precis. Eng. Manuf., Vol. 14, No. 8, pp. 1447–1454, 2013.
Yu, T.-K., Yu, C., and Orlowski, M., “Combined Asperity Contact and Fluid Flow Model for Chemical-Mechanical Polishing,” Proc. of the International Workshop on Numerical Modeling of Processes and Devices for Integrated Circuits, NUPAD V., pp. 29–32, 1994.
Burwell, J. T., “Wear,” Vol. 1, pp. 119–141, 1957.
Ahmadi, G. and Xia, X., “A Model for Mechanical Wear and Abrasive Particle Adhesion during the Chemical Mechanical Polishing Process,” Journal of the Electrochemical Society, Vol. 148, No. 3, pp. G99-G109, 2001.
Basim, G., Adler, J., Mahajan, U., Singh, R., and Moudgil, B., “Effect of Particle Size of Chemical Mechanical Polishing Slurries for Enhanced Polishing with Minimal Defects,” Journal of the Electrochemical Society, Vol. 147, No. 9, pp. 3523–3528, 2000.