Hostname: page-component-848d4c4894-xm8r8 Total loading time: 0 Render date: 2024-06-30T22:27:58.519Z Has data issue: false hasContentIssue false

Uni-axial Cracking of ITO to Form Row and Column Electrodes for Roll to Roll Production of Flexible Displays and Electronics

Published online by Cambridge University Press:  28 February 2013

John Lawton West
Affiliation:
Liquid Crystal Institute, Kent State University, Kent, Ohio, USA;
Miko Cakmak
Affiliation:
Polymer Engineering, University of Akron, Akron, Ohio, USA
Tsang-Min Huang
Affiliation:
Polymer Engineering, University of Akron, Akron, Ohio, USA
Da-Wei Lee
Affiliation:
Liquid Crystal Institute, Kent State University, Kent, Ohio, USA;
Get access

Abstract

Uniformly uni-axially aligned electrodes are formed by uniaxially cracking an indium tin oxide, ITO, film vacuum deposited on a polyester substrate. The cracks are produced by bending the film around a small radius of curvature, producing narrow, parallel cracks in the ITO separated by 5-10 μm. The cracks are enhanced by etching or uniaxial stretching. Heating and stretching is the most effective, producing a crack width of about 0.05 μm and a differential conductivity (measured parallel and perpendicular to the cracks) several orders of magnitude or greater. A passive matrix bistable cholesteric display is fabricated using top and bottom substrates with perpendicularly aligned electrodes. The addressed lines on each substrate are defined by the contact electrode, which contacts multiple cracked ITO lines. Because of the small dimension of the cracks (much less than the thickness of the active layer) they are not visible in the display. The separation between the contact electrodes must be great than 20 μm in order to include at least one crack and electrically isolate each individual line. The resulting display demonstrates how controlled cracking of ITO can replace photolithographic etching of ITO or printing of conducting polymers to produce the line electrodes required for flexible, passive matrix displays and related electronic applications. Un-axially cracking can be easily integrated into a roll-to-roll manufacturing process.

Type
Articles
Copyright
Copyright © Materials Research Society 2013

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

Volynskii, A. L., Bazhenov, S., Lebedeva, O. V., Ozerin, A.N. and Bakeev, N.F., “Multiple Cracking of Rigid Platinum Film Covering Polymer Substrate,” Journal of Applied Polymer Science, Vol. 72, p.1267, 1999.3.0.CO;2-3>CrossRefGoogle Scholar
Cairns, D. R., and Crawford, C.P, “Electromechanical Properties of Transparent Conducting Substrates for Flexible Electronic Display,” Proceedings of the IEEE, Vol. 93, No. 8, p1451, 2005.CrossRefGoogle Scholar
Königer, T., and Munstedt, H., “Advanced device for testing the electrical behavior of conductive coatings on flexible polymer substrates under oscillatory bending: comparison of coatings of sputtered indium-tin oxide and poly3,4ethylenedioxythiophene,” Measurement Science and Technology, Vol. 19, 055709, 2008.CrossRefGoogle Scholar
West, J. L., Cakmak, M., Huang, T.-M., Lee, D.-W., SID Symposium Digest of Technical Papers, Vol. 43, 1368–71, 2012.CrossRefGoogle Scholar
West, J. L., Rouberol, M., Francl, J.J., Ji, Y., Doane, J.W., Pfeiffer, M., “Flexible Displays Utilizing Bistable, Reflective Cholesteric/Polymer Dispersions and Polyester Substrates,” Asia Display '95, Proc. 15th International Display Research Conference, Vol. 55, October 1995.Google Scholar