Stiction analysis of magnetic tapes

This study investigates the differences between two MP tapes exhibiting different stiction behavior. Surface roughness and microscale friction of the tapes were measured using an Atomic Force/Friction Force Microscope (AFM/FFM). Numerical modeling was used to predict the contact area of the tape surfaces which were verified by actual measurement. Hardness and elastic modulus of the tapes were determined using a nanoindenter. Bending stiffness of the tapes was also measured. We found that the tape exhibiting lower stiction showed lower contact area primarily due to higher kurtosis of the surface in addition to higher elastic modulus, hardness and bending stiffness than the tape exhibiting higher stiction. Based on this study, tapes with surfaces exhibiting high kurtosis are desirable for good stiction behavior. Higher values of elastic modulus and bending stiffness are also favorable for low stiction. We also found that roughness measurements made with the AFM yielded better lateral resolution in tapping mode as compared to the conventional contact mode.