Journal of the Semiconductor & Display Technology (반도체디스플레이기술학회지)

The Korean Society Of Semiconductor & Display Technology (한국반도체디스플레이기술학회)
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Fracture Analysis of a $SiN_x$ Encapsulation Layer for Flexible OLED using Electrical Methods

전기적 기법을 통한 플렉서블 OLED 봉지막의 파괴특성 연구

  • Kim, Hyuk Jin (Development Center (LCD), Samsung Display) ;
  • Oh, Seungha (Department of Materials Science and Engineering, Seoul National University) ;
  • Kim, Sungmin (Department of Materials Science and Engineering, Seoul National University) ;
  • Kim, Hyeong Joon (Department of Materials Science and Engineering, Seoul National University)
  • Received : 2014.11.06
  • Accepted : 2014.11.28
  • Published : 2014.12.31
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Abstract

The fracture analysis of $SiN_x$ layers, which were deposited by low-temperature plasma enhanced chemical vapor deposition (LT-PECVD) and could be used for an encapsulation layer of a flexible organic light emitting display (OLED), was performed by an electrical method. The specimens of metal-insulator-metal (MIM) structure were prepared using Pt and ITO electrodes. We stressed MIM specimen mechanically by bending outward with a bending radius of 15mm repeatedly and measured leakage current through the top and bottom electrodes. We also observed the cracks, were generated on surface, by using optical microscope. Once the cracks were initiated, the leakage current started to flow. As the amount of cracks increased, the leakage current was also increased. By correlating the electrical leakage current in the MIM specimen with the bending times, the amount of cracks in the encapsulation layer, generated during the bending process, was quantitatively estimated and fracture behavior of the encapsulation layer was also closely investigated.

Keywords

References

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