Some embodiments relate to a method of processing a workpiece. The workpiece includes a first surface region having a first wettability coefficient, and a second surface region having a second wettability coefficient that differs from the first wettability coefficient. A liquid, which corresponds to an optical structure, is dispensed on the first and second surface regions of the workpiece, wherein the liquid self-aligns to the second surface region due to the difference between the first and second wettability coefficients. The self-aligned liquid is hardened to form the optical structure.