Investigation for the Relation between the Conditions of the Ion Beam Process and the Physical Parameters of Polyimide

The physical characteristics of ion-beam (IB)-treated polyimide (PI) surfaces as a function of the IB energy were investigated via spectroscopic techniques. PI's properties for the LC alignment were noted to be improved as the IB energy was increased until an optimal value of the treating energy was reached. On the contrary, the properties reversed and were degraded as the IB energy was increased above the optimal value. Using Raman spectroscopic measurements, we confirmed that the strongly IB-treated PI above the optimal value of treating energy was chemically accelerated to change into a hydrogenated amorphous carbon-like structure, which ultimately degraded the physical characteristics of PI.