Residual Interfacial Deformation in Flexible Copper Clad Laminate Occurring During Roll-to-Roll Composite Film Manufacturing

Abstract

Flexible copper clad laminate has been used to fabricate flexible electronics such as bio-inspired tactile sensor, microfluidicsbased sensor, and flexible printed circuits board. Herein, the effects of thermal property difference between the component layers on the residual interfacial deformation in a flexible copper clad laminate occurring during roll-to-roll composite film manufacturing were analyzed. The thermal behaviors of polyimide film and copper meshes in the laminate were examined, and it was found that differences of the coefficient of thermal expansion and elastic modulus between the two components could cause the residual deformation in the laminate. The three factors affecting the residual strain due to the thermal characteristic difference, i.e., temperature and pressure of the lamination roll and web tension, were selected in the controllable operating conditions in a roll-to-roll lamination process. Mathematical models to estimate the elastic and thermal residual strains according to the factors were developed and experimentally verified. Finally, the effects of the three factors on the residual strain in the laminate were determined using the developed model. In this study, we demonstrate that, in the lamination process, the thermal strain of the laminate component materials after thermal cycling generates a significant residual deformation, which causes defects in the flexible copper clad laminate. The developed model can be used to accurately estimate the residual elastic and thermal residual strains occurring during the roll-to-roll manufacturing according to the process conditions.

Transmittance Control of a Water-Repellent-Coated Layer on a Tensioned Web in a Roll-to-Roll Slot-Die Coating System

“…Figure 10 indicates the transparency of the transparent water-repellent film manufactured under the process conditions derived using the developed model. When the transparent water-repellent film has a contact angle greater than 130 • , self-cleaning is possible [33][34][35]. The tension and coating gap required to achieve a film with which the contact angle is greater than 130 • were determined to be 3.7 kgf and 150 µm, respectively, using our model.…”

“…From these results, the transmittance according to the tension can be estimated, and a high-quality, transparent, self-cleaning film can be obtained based on the model. self-cleaning is possible [33][34][35]. The tension and coating gap required to achieve a film with which the contact angle is greater than 130° were determined to be 3.7 kgf and 150 µm, respectively, using our model.…”

Hydrocarbon Resin-Based Composites with Low Thermal Expansion Coefficient and Dielectric Loss for High-Frequency Copper Clad Laminates

“…As an important part of these electronic devices, the printed circuit board (PCB) that provides electrical connection between electronic components needs not only higher integration but also greater data transmission capacity [ 2 , 3 , 4 ]. The material, stack-up design, channel design, power noise filtering, termination schemes of PCB will greatly affect the data transmission capacity [ 5 , 6 , 7 ]. It is well known that substrates with low dielectric constant (D k ) and D f can achieve characteristics of high fidelity and low delay in the process of high-frequency signal transmission.…”

Effect of Radial Stress on the Nanoparticle-Based Electrolyte Layer in a Center-Wound Roll with Roll-to-Roll Systems

“…Roll-to-roll systems are suitable candidates for achieving high speed and mass production of flexible functional devices, such as flexible printed electronics, solar cells, fuel cells, bioelectric sensors, and pressure capacitive sensors [ 1 , 2 , 3 , 4 , 5 , 6 , 7 ]. The slot-die coating process has the advantages of a large-area and pre-metered coating; therefore, it is used in the mass production of large-area functional layers [ 8 , 9 , 10 , 11 ].…”