Browse > Article
http://dx.doi.org/10.7464/ksct.2021.27.1.17

Cu Blackening through CuO Oxidation for the Application of Camera Lens Spacers in Mobile Phones  

Lee, Yeji (Department of Chemical Engineering, Pukyong National University)
Kim, Yong Ha (Department of Chemical Engineering, Pukyong National University)
Kim, Chang Hyun (Haneul Solution)
Won, Yong Sun (Department of Chemical Engineering, Pukyong National University)
Publication Information
Clean Technology / v.27, no.1, 2021 , pp. 17-23 More about this Journal
Abstract
Black polymer spacers are currently used for physically separating aligned camera lenses in camera modules of mobile phones. However, the mechanical properties of polymer spacers have their limits, especially in the current trend of using more lenses in thinner camera modules. Thus, copper (Cu) becomes a good candidate for those polymer spacers because of its superior mechanical properties and its inherent blackness due to its black surfaced oxides, such as copper (II) oxide (cupric oxide, CuO). The latter property is critical in quality control because the closer the color of a spacer is to black, the less light interference and flaring phenomena can occur. A standard Cu blackening process and its operational conditions were proposed in this study through a comprehensive analysis of previous research and patents. The Cu blackening process is composed of cleaning, deoxidizing, activating, blackening and sealing. The effects of operational parameters, such as the temperature of each unit process and the activator concentration, were then investigated by measuring the blackness of the Cu strips with a colorimeter. The proposed operational conditions were determined by whether the blackness of Cu strips was within the on-spec. value used in the field.
Keywords
Blackening process; Black oxide; Cupric oxide (CuO); Spacer; Camera module;
Citations & Related Records
연도 인용수 순위
  • Reference
1 Lee, K. T., "The Endless Evolution of Smartphone Cameras... Do Digital Cameras Step on the mp3 Train?," ChosunBiz (2019. 11. 25).
2 Noh, J. D., "Than Speed and Design... Now the Smartphone is in Camera War," The Korea Economic Daily (2019. 10. 3).
3 Song, J. Y., "[34th Anniversary Special Feature] Little Korea Goes to Vietnam <4> Haesung Optics in the Business Transition Point..," Korea IT News (2016. 9. 21).
4 Lebbai, M., Kim, J.-K., Szeto, W. K., Yuen, M. M. F., and Tong, P., "Optimization of Black Oxide Coating Thickness as an Adhesion Promoter for Copper Substrate in Plastic Integrated-circuit Packages," J. Electron. Mater., 32(6), 558-563 (2003).   DOI
5 Hu, Y. Z., Sharangpani, R., and Tay, S.-P., "In Situ Rapid Thermal Oxidation and Reduction of Copper Thin Films and Their Applications in Ultralarge Scale Integration," J. Electrochem. Soc., 148(12), G669-G675 (2001).   DOI
6 Maruyama, T., "Copper Oxide Thin Films Prepared by Chemical Vapor Deposition from Copper Dipivaloylmethanate," Sol. Energy Mater. Sl. Cells, 56(1), 85-92 (1998).   DOI
7 Oral, A. Y., Mensur, E., Aslan, M. H., and Basaran, E., "The Preparation of Copper (II) Oxide Thin Films and the Study of Their Microstructures and Optical Properties," Mater. Chem. Phys., 83(1), 140-144 (2004).   DOI
8 Xiang, J. Y., Tu, J. P., Huang, X. H., and Yang, Y. Z., "A Comparison of Anodically Grown CuO Nanotube Film and Cu2O Film as Anodes for Lithium Ion Batteries," J. Solid State Electrochem., 12(7-8), 941-945 (2008).   DOI
9 Miley, H. A., "Copper Oxide Films," J. Am. Chem. Soc., 59(12), 2626-2629 (1937).   DOI
10 Hwang, H. I., "Processing method of black oxide of heat sink for semi-conductor," K.R. Patent No. 10-2000-0017462 (2002).
11 Nam, B. W., and Chang, Y. S., "Alkali etching method and manufacturing method using the same," K.R. Patent No. 10-2009-0006467 (2011).
12 Ha, H. K., "Printed circuit board and method of the same," K.R. Patent No. 10-2010-0138241 (2012).
13 Ko, W. D., "Spacer for camera lens," K.R. Patent No. 10-2012-0044041 (2012).
14 Lee, H. S., Bae, S. R, and Hong, O. W., "Lens spacer for camera and manufacturing method therefor," K.R. Patent No. 10-2016-0184272 (2017).
15 Kim, C. J., Kim, P. S., Lee, D. S., Jeong, U. S., Choi, K. M., and Choi, K. H., "Solution for forming black oxide layer on metal thin film, method for forming black oxide layer on metal thin film of electromagnetic interference filter and metal thin film of electromagnetic interference filter formed by the same method," K.R. Patent No. 100582900B1 (2006).
16 Kim., S. J., and Cho, W. J., "Semi-additive process with improved contact strength of electroplating copper layer for printed circuit board," K.R. Patent No. 10-2009-0081706 (2011).
17 Mazda, M., Yoshikawa, M., and Fujimoto, T., "Electrolysis copper alloy foil and electrolysis copper alloy foil with carrier foil," K.R. Patent No. 10-2014-7013943 (2019).
18 Krishnan, S., Haseeb, A. S. M. A., and Johan, M. R., "One Dimensional CuO Nanocrystals Synthesis by Electrical Explosion: A Study on Structural, Optical and Electronic Properties," J. Alloy. Compd., 586, 360-367 (2014).   DOI
19 Ohno, Y., "CIE Fundamentals for Color Measurements," IS&T's NIP16: Int. Conf. Digital Print. Technol., 16, 540-545 (2000).
20 Kim, I. B., and Kang, B. G., "Composition for blackening Metal Thin Film," K.R. Patent No. 10-2016-0098017 (2017).