Reliability of Flexible LTPS TFTs under Dynamic Mechanical Stress

Reliability of p-type flexible low-temperature poly-Si (LTPS) thin-film transistors (TFTs) under dynamic mechanical stresses including dynamic stretch and bending is investigated. Under dynamic stretch, a positive $V_{\mathrm{G}}$ shift in the transfer curve is observed. Two types of crack induced failure model are proposed. Under dynamic bending, a similar positive $V_{G}$ shift of transfer curves is observed. Approximately the degradation follows a liner trend with the number of bending cycles and curvature. Moreover, an abnormal spontaneous degradation phenomenon after dynamic bending is observed. A model of “electrons transport and capture” with assist of O 2 ambient is proposed to explain the spontaneous degradation.