염화칼륨 농도에 따른 사파이어 기판 CMP에 관한 연구
Study on Effect of KCl Concentration on Removal Rate in Chemical Mechanical Polishing of Sapphire
2
조회
0
다운로드
1
인용
0
참고문헌
키워드
초록
Chemical Mechanical Polishing of chemically stable sapphire substrates is dominantly affected by the mechanical processing of abrasives, in terms of the material removal rate. In this study, we investigated the effect of electrostatic force between the abrasives and substrate, on the polishing. If potassium chloride (KCl) is added to slurry, water molecules are decomposed into H+ and OH− ions, and the amount of ions in the slurry changes. The zeta potential of the abrasives decreases with an increase in the amount of H+ ions in the stern layer; consequently, the electrostatic force between the abrasives and substrate decreases. The change in zeta potential of abrasives in the slurry is affected by the slurry pH. In acidic zones, the amount of ions bound to the abrasives increases if the amount of H+ ions is increased by adding KCl. However, in basic zones, there is no change in the corresponding amount. In acidic zones, zeta potential decreases as molar concentration of potassium increases; however, it does not change significantly in basic zones. The removal rate tends to decrease with increase in molar amount of potassium in acidic zones, where zeta potential changes significantly. However, in basic zones, the removal rate does not change with zeta potential. The tendencies of zeta potential and that of the frictional force generated during polishing show strong correlation. Through experiments, it is confirmed that the contact probability of abrasives changes according to the electrostatic force generated between the abrasives and substrate, and variation in removal rate.
Abstract
Chemical Mechanical Polishing of chemically stable sapphire substrates is dominantly affected by the mechanical processing of abrasives, in terms of the material removal rate. In this study, we investigated the effect of electrostatic force between the abrasives and substrate, on the polishing. If potassium chloride (KCl) is added to slurry, water molecules are decomposed into H+ and OH− ions, and the amount of ions in the slurry changes. The zeta potential of the abrasives decreases with an increase in the amount of H+ ions in the stern layer; consequently, the electrostatic force between the abrasives and substrate decreases. The change in zeta potential of abrasives in the slurry is affected by the slurry pH. In acidic zones, the amount of ions bound to the abrasives increases if the amount of H+ ions is increased by adding KCl. However, in basic zones, there is no change in the corresponding amount. In acidic zones, zeta potential decreases as molar concentration of potassium increases; however, it does not change significantly in basic zones. The removal rate tends to decrease with increase in molar amount of potassium in acidic zones, where zeta potential changes significantly. However, in basic zones, the removal rate does not change with zeta potential. The tendencies of zeta potential and that of the frictional force generated during polishing show strong correlation. Through experiments, it is confirmed that the contact probability of abrasives changes according to the electrostatic force generated between the abrasives and substrate, and variation in removal rate.
참고문헌 (19)
- 이현섭, "Mechanical Aspects of the Chemical Mechanical Polishing Process: A Review", International Journal of Precision Engineering and Manufacturing, 17(4), pp.525~536 (2016), 한국정밀공학회
- 이현섭, "Mathematical Model-Based Evaluation Methodology for Environmental Burden of Chemical Mechanical Planarization Process", International Journal of Precision Engineering and Manufacturing-Green Technology, 1(1), pp.11~15 (2014), 한국정밀공학회[DOI]
- 이창석, "Analysis of Pressure Distribution and Verification of Pressure Signal by Changes Load and Velocity in Chemical Mechanical Polishing", International Journal of Precision Engineering and Manufacturing, 16(6), pp.1061~1066 (2015), 한국정밀공학회
- 이창석, "Development of Intelligent Pad Monitoring System and Application to Analysis of Pressure Distribution in Chemical Mechanical Polishing Process", International Journal of Precision Engineering and Manufacturing, 15(9), pp.2005~2009 (2014), 한국정밀공학회
- Hyunseop Lee, "Macroscopic and Microscopic Investigation on Chemical Mechanical Polishing of Sapphire Wafer", Journal of Nanoscience and Nanotechnology, 12, pp.1256~1259 (2012)
- Hong Lei, "Preparation of Ce-doped colloidal SiO2 composite abrasives and their chemical mechanical polishing behavior on sapphire substrates", Materials Chemistry and Physics, 172, pp.26~31 (2016)
- Ryan J. Kershner, "Zeta potential orientation dependence of sapphire substrates", Langmuir, 20, pp.4101~4108 (2004)
- Li Xu, "Fe-Nx", C assisted chemical–mechanical polishing for improving the removal rate of sapphire, 2015, pp.343, 115~120
- Lee, M Cook, "Chemical processes in glass polishing", Journal of Non-Crystalline Solids, 120(1-3), pp.152~171 (1990)
- F. Gareeva, "Electrokinetic properties of detonation nanodiamond aggregates in aqueous KCl solutions", Colloids and Surfaces A, Aspects, 440, pp.202~207 (2014)
- Ragesh Prathapan, "Modulating the zeta potential of cellulose nanocrystals using salts and surfactants", Colloids and Surfaces A, Aspects, 509, pp.11~18 (2016)
- K. Hanumantha Rao, "Mechanism of oleate interaction on salt-type minerals Part III. Adsorption, zeta potential and diffuse reflectance FT-IR studies of scheelite in the presence of sodium oleate", Colloids and Surfaces, 54, pp.161~187 (1991)
- J. Callejas-Fernandez, "The role of ζ-potential in the colloid stability of calcium oxalate dihydrate dispersions. 2. Effect of several additives", Colloids and Surfaces, 66, pp.129~137 (1992)
- Ningning Li, "Adsorption of non-ionic surfactants to the sapphire", solution interface – Effects of temperature and pH, 2012, pp.369(1), 287~293
- Willem Smit, "Electroosmotic zeta potential measurements on single crystals", Journal of Colloid and Interface Science, 60(2), pp.299~307 (1977)
- 김진근, "Characteristics of Zeta Potential Distribution in Silica Particles", Bulletin of the Korean Chemical Society, 26(7), pp.1083~1089 (2005), 대한화학회
- Guozhong Cao, "Nanostructures and Nanomaterials Synthesis, Properties, and Applications, World Scientific Series in Nanoscience and Nanotechnology" (2004), World Scientific
- Zefang Zhang, "Effect of mechanical process parameters on friction behavior and material removal during sapphire chemical mechanical polishing", Microelectronic Engineering, 88(9), pp.3020~3023 (2011)
- 이현섭, "CMP 공정에서 마찰에너지가 연마결과에 미치는 영향", 대한기계학회논문집 A, 28(11), pp.1807~1812 (2004), 대한기계학회