In a flat display panel, a surface of at least one of a sustain electrode and an address electrode may be formed to have a curved surface. The surface of the electrode may be formed as a continuous curved surface. The sustain electrode and the address electrode may be elongated in a lengthwise direction thereof. These lengthwise directions may be perpendicular to each other. The electrode may be formed by transferring an electrode material onto the substrate using an electrode frame defined with electrode forming grooves each having a same sectional shape as the electrode. Therefore, the surface of the electrode may be formed as the curved surface.