The characteristics of surface morphology on the polystyrene thin film using DC-bias oxygen plasma treatment

Plasma oxygen has been extensively used for plasma surface modification because it can improve surface roughness, wettability, and surface morphology. Modification of the surface materials using oxygen plasma is an important factor in altering the material’s surface properties without affecting the overall coating, which can be applied in the QCM sensor or biosensor. The oxygen plasma treatment of the polystyrene surface deposited on the QCM sensor was evaluated by plasma parameters such as DC-Bias voltage. The DC-Bias voltage was varied from -150 volts to -550 volts. The effect of DC-bias on polystyrene’s surface morphology and surface properties was observed using a Scanning Electron Microscope, and a profilometer was examined. The effect of DC bias voltage on the PS surface morphology was compared with DC bias and without DC bias treatment. The Investigation of SEM photo morphological observations showed the RIE (Reactive ion etching) process occurred. The reason could be related to the interaction between the plasma ion with the polystyrene layer. It is indicated by the surface morphology changes of the PS. The morphological alteration after the plasma process indicates that there are micro-structures randomly distributed.