Abstract:
For the PTFE copper clad laminate, the peel strength between the copper foil and the substrate is one of the most critical factors for its reliability. To improve the bonding property of the pure PTFE, the base material is modified by the filtered magnetic deposition combined with the ion implantation technology, and then the PTFE copper clad laminate is prepared by electroplating. SEM and XPS are used to analyze the surface morphology, the microstructure, and the composition of the modified PTFE sample. The surface tension of the sample is determined using a Dyne test pen. The influence of different thickness transition layers on the implanted ions is simulated by the SRIM software, together with the changes of the atomic density with the matrix depth. In addition, the peel strength of the modified PTFE copper clad laminate is measured in the liquid nitrogen or thermal stress environment, using a 90° peel strength tester. The conductivity and dielectric loss properties are investigated by a broadband dielectric impedance spectrometer. The experimental results demonstrate that the surface morphology of the PTFE treated by the ion implantation has changed significantly, forming a transition layer of the copper foil and the PTFE organically combined. The bonding property of the PTFE copper clad laminate is improved with the peel strength rising to 0.74 N/mm. Though the peel strength decreases slightly in the liquid nitrogen, with the thermal stress or in the dip soldering environment, the electrical properties of the copper clad laminate can still meet the requirement.