In-situ field magnetic force microscopy investigation of magnetic domain patterns in Co/CoO films

Ferromagnetic thin film multilayers have been shown to create magnetic field patterns. These patterns can be used as a means of storing information, and the development of several magnetic recording technologies relies on the good understanding of the magnetic domain structures that occur in these films. In this experiment, I imaged the magnetic field structure of single Co/CoO thin films at various magnetic field values using in-situ field magnetic force microscopy. The objective of this experiment was to study the effect of Co thickness on the magnetization of the thin films. In particular, I wanted to find out the direction of the magnetization as it goes from in-plane to out-of-plane. The resulting images show that the Co/CoO samples do show signs of the magnetic anisotropy going from in-plane to out-of-plane, but lacked the defined shapes that were present on other ferromagnetic thin films such as Co/Pt multilayers. I also concluded that thicker and thinner samples tend to show less contrast in their magnetic domain patterns than the intermediate thickness samples, which suggests that the thickness of the sample has an effect on the magnetic morphology of Co/CoO thin films.