Resist sidewall slopes frequently need to be adjusted in micro-and nanofabrication. In this paper, the authors present a straightforward approach to adjust sidewall slopes by using electron beam lithography and applying a background dose in addition to the feature dose. The underlying effect is attributed to an inhomogeneous energy deposition along the resist depth, for which a threedimensional point spread function is necessary to correctly describe the energy deposition in the resist even for large acceleration voltages and thin resist films. This enables adjacent features with different positive or different negative slopes within a single lithographic step. Corresponding experimental results obtained with the two positive tone resists poly(methyl methacrylate) and ZEP520A are shown, and their opposed sidewall behavior is explained. Moreover, a customized contrast curve is discussed that can, in theory, be used to achieve resist profiles with positive and negative slopes for the same resist. Therefore, a full range tuning on the same substrate becomes feasible. V