Hostname: page-component-76fb5796d-zzh7m Total loading time: 0 Render date: 2024-04-26T14:22:47.405Z Has data issue: false hasContentIssue false
  • English
  • Français

Visible ITO Pattern in Capacitive Touch Lens: Cause and Countermeasure

Published online by Cambridge University Press:  05 April 2011

Duk Su Kim ,
Gyeong-Geun Lee ,
Jacob Yang  and
Dong Hyuk Shin
Duk Su Kim
Affiliation:
R&D Center, ELK Corporation, Daejeon, Korea, Republic of;
Gyeong-Geun Lee
Affiliation:
Nuclear Materials Research Division, Korea Atomic Energy Research Institute, Daejeon, Korea, Republic of.
Jacob Yang
Affiliation:
R&D Center, ELK Corporation, Daejeon, Korea, Republic of;
Dong Hyuk Shin
Affiliation:
R&D Center, ELK Corporation, Daejeon, Korea, Republic of;
Get access

Abstract

Market demand for touch panel/lens has been exceptionally high for the recent years due to smartphones, tablet PCs, etc. Among the available technologies to envision touch functionality, capacitive touch screen has received the great attention due to the various superiorities over the competing ones. Capacitive touch screen features two transparent conductive electrodes, such as ITO (indium tin oxide). However, the difference in refractive indices of ITO, substrate, and air, ITO pattern is clearly visible if there is no proper countermeasure. Most of touch screen makers and ITO substrate supplier utilize “index-matching technology” to prevent this phenomenon.

Even though of the attempts to minimize visible ITO pattern in final product, there are many technical and process challenges. In this study, the causes around visible ITO pattern were investigated to understand and provide the proper countermeasures.

One of the possible causes for visible ITO pattern was improper annealing process in ITO especially for film substrate. According to XPS (X-ray photoelectron spectroscopy)/ESCA (electron spectroscopy for chemical analysis) and other analysis results, ITO, which is normally deposited through sputtering, is not fully transformed to oxidized state. After aligning and adjusting annealing condition, acknowledged visible ITO pattern was disappeared.

Other causes for visible patterns were also discussed in detail, and the relevant countermeasures were provided.

Keywords

transparent conductorx-ray photoelectron spectroscopy (XPS)annealing
Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 1315: Symposium MM – Transparent Conducting Oxides and Applications , 2011 , mrsf10-1315-mm03-01
Copyright
Copyright © Materials Research Society 2011

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Touch screens in mobile devices to deliver $5 billion next year, Press release, ABI Research, 2008-09-10.Google Scholar
2. Usher, D. M., Ilett, C., Displays, Vol. 7 No. 2, 59–66, 1986.Google Scholar
3. Colegrove, J., Info. Display, Vol. 26 No. 3, 22–24, 2010.Google Scholar
4. Yan, X., Mon, F. W., Poxson, D. J., Schubert, M. F., Kim, J. K., Cho, J., Schubert, E. F., Japanese J. Appl. Phys., Vol. 48, 120203, 2009.Google Scholar
5. Michette, A. G., Wang, Z., Opt. Comm., Vol. 177 No. 1–6, 47-55, 2000.Google Scholar
6. Uchida, T., Wakana, M., Satoh, T., Proceeding of ICCE-17 (International Conference on Composite/Nano Engineering), 2009.Google Scholar
7. Bertrand, P. A., Vac, J.. Sci. Technol., Vol. 18 No. 1, 28–33, 1981.Google Scholar
8. Kerkache, L., Layadi, A., Dogheche, D., Remiens, D., J. Phys. D: Appl. Phys., Vol. 39 No. 1, 184, 2006 Google Scholar