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http://dx.doi.org/10.7736/KSPE.2013.30.5.552

A Study on the Design of Flexible Display Considering the Failure Characteristics of ITO Layer  

Kim, Min Gyu (Department of Mechanical Engineering, Graduate school of Korea Univ.)
Park, Sang Baek (Department of Mechanical Engineering, Graduate school of Korea Univ.)
Chae, Soo-Won (Department of Mechanical Engineering, Korea Univ.)
Publication Information
Journal of the Korean Society for Precision Engineering / v.30, no.5, 2013 , pp. 552-558 More about this Journal
Abstract
In recent years the interest on flexible display has been increasing as a future display due to its bendable characteristics. An ITO(indium tin oxide) layer, which is part of a flexible display, can be broken easily while bending because it is made of brittle materials. This brittle property can cause the malfunction of flexible display. To analyze fracture characteristics of ITO layer, bending test was conducted commonly. However, it is not possible to know specific phenomena on bended ITO layer by simple bending test only. Accordingly, in this study, the FE(finite element) model is developed similarly to a real flexible display to analyze stress distribution of flexible display under bending condition, especially on ITO layer. To validate FE model, actual bending test was conducted and the test results were compared with the simulation results by measuring reaction forces during bending. By using the developed model, FE analysis about the effect of design parameter (Thickness & Young's Modulus of BL) on ITO Layer was performed. By explained FE analysis above, this research draws a conclusion of reliable design guide of flexible display, especially on ITO layer.
Keywords
Finite element method; Flexible display; Bending test; Barrier layer; Nano-indentation;
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