Surface potential and magnetic properties of La_0.7Sr _0.3MnO₃ periodic arrays fabricated by direct electron beam writing

It is demonstrated that magnetic periodic arrays can be easily fabricated from direct writing water developable La_0.7Sr_0.3MnO ₃ electron beam resist. Two unique features of our approach are (1) the patterned La_0.7Sr_0.3MnO₃ resist film can be developed using nontoxic and environmentally friendly pure water and (2) either positive or negative patterns can be fabricated depending on the dosage of electron beam. The mechanism of the dual function characteristic of the resist was studied using Kelvin probe microscope. The surface potential of patterned La_0.7Sr_0.3MnO₃ resist increases with increasing electron beam dosage due to the changes of resist composition. The formations of periodic magnetic arrays were confirmed by the studies of scanning electron microscope and magnetic force microscope. The magnetization of La _0.7Sr_0.3MnO₃ can be enhanced by postsintering the sample at 900°C after electron beam irradiation. We have therefore provided a one-step, simple, and convenient alternative technique for the fabrication of nanoscale magnetic patterns, which form the building blocks for the study of physical properties in periodic magnetic arrays.