In the thin film transistors (TFTs) device research for foldable display, the degradation effect by the mechanical stress is crucial. Here, the crack position is critical for TFT reliability. However, it is difficult to characterize the crack position due to the random generation of the crack by mechanical stress. In this paper, the crack-guided low temperature polycrystalline silicon (LTPS) TFT test structures are fabricated and the crack-guided effects on mechanical stress of the tested TFT structure are analyzed. To strain on the foldable LTPS TFTs, 50,000 cycles of tensile and parallel direction dynamic mechanical stresses were applied with 2.5-mm bending radius. Based on the results, the generating crack position can be guided and controlled and also TFT reliability for foldable display can be enhanced.
Bibliographical noteFunding Information:
This research was supported by the LG Display ( 2014-11-1905 ). This work was also supported by Institute of BioMed-IT, Energy-IT and Smart-IT Technology (BEST), a Brain Korea 21 plus program, Yonsei University ( 2016-11-0007 ).
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Safety, Risk, Reliability and Quality
- Condensed Matter Physics
- Surfaces, Coatings and Films
- Electrical and Electronic Engineering