In this article, we propose a fabrication technology for preparing curved structures using an electron-beam writing strategy. Oxygen plasma treatment increases the surface roughness of SU-8 polymer, while minimizing the outgassing problem and stabilizing the SU-8 film. Fourier transform infrared spectra of epoxy bond near 915 cm(-1) decreased upon increasing the dosage of the electron beam or the treatment time of the oxygen plasma. Convex, concave, and spiral structures were formed successfully using a gradient dosing strategy. The interface between two shot sections was smoothed by the electron scattering effect. The curved profile was fabricated at various curvatures, and characterized using scanning electron microscopy and a profiler. In addition, a spiral structure was fabricated that possesses the advantageous feature of having a small chip area. We discuss a method of characterizing the spiral structure. (C) 2004 American Vacuum Society.