P‐12.3: Analysis and Application of COF Peeling Failure in Display

Abstract

In order to solve the problem of COF peeling on OLB (Outer Lead Bonding) side of high curvature display screen, this paper studied the peeling failure strength of COF Bonding so as to guide product design through the combination of experiment and simulation. Firstly, basic peeling test of the COF was carried out under the condition of 60 ℃/90%RH HTHHO, and the COF peeling load was obtained; Then, the linear stress of COF under the peeling load was 0.18 N/mm by finite element numerical simulation; Finally, the COF twist model of 32‐inch R1000 module was established, and the maximum COF twist value was 3mm under the maximum linear stress of 0.18 N/mm at COF Bonding; The module has passed the 60 ℃/90%RH HTHHO 500h test, which verified the accuracy of COF peeling failure judgment method. Considering the safety factor of 2, the linear stress intensity standard of this Bonding process was determined to be about 0.09 N/mm. Based on the above‐mentioned linear stress intensity standard, the 27‐inch curved surface module was optimized from double PCB to single PCB, which passed the verification of high temperature and high humidity condition and met the product quality requirements. The method proposed in this paper can guide module optimization design, reduce the risk of peeling failure at COF Bonding on the source side of curved screen, and improve product reliability.