Simulation Study On Bending Behavior Of Metal Trace/etched Layer At The OLED Panel Pad

OLED has attracted wide attention due to its wide viewing angle,light and thin,flexible,wide color gamut and impact resistance.The high-screen OLED panel has gradually become the main direction of smart phone screen development.However,in order to pursue a higher OLED screen ratio,a method of bending the metal trace/etched layer structure at the pad panel toward the back side is generally employed.In this process,the metal traces at the panel pad are prone to excessive stress or breakage,which causes problems in the panel display,so the OLED screen yield with a high-screen ratio is low.In this paper,the metal trace/etched layer structure of the OLED panel pad is modeled,and bending mechanical response and fracture properties of the metal trace are analyzed.And reasonable optimization suggestions for the pad bending process of the OLED panel are proposed.The main contents include:(1)According to the mesostructure of the OLED panel pad,a metal trace/etched layer model was established.Periodic boundary conditions and special boundary conditions based on the overall model are introduced.The influence of different metal trace structure,material layer thickness and substrate material on metal trace stress is analyzed.(2)Based on the interface crack deflection and penetration theory of composite materials and the virtual crack closure method,the model of metal trace cracking is established by using finite element software.The extended form of crack in metal trace/etched layer is analyzed.And based on the extended finite element of circle trace integration,the effect of pore on the stress intensity factor of the metal trace is studied.(3)Based on the extended finite element method,the three-dimensional crack propagation process in the metal trace/etched layer structure is simulated.The influence of substrate material and opening diameter on the fracture properties of the metal trace/etched layer structure is discussed.In this paper,the bending behavior and fracture properties of the metal trace/etched layer structure of the OLED are simulated.The results obtained provide an important reference for designers to realize the pad bending of OLED panels,which has important practical significance.