Liquid Crystals have many applications in photonics, but often the geometrical
properties of the photonic structures give problems for controlling the alignment of the liquid crystal. We demonstrate the effect on the orientation of a nematic liquid crystal by structures etched in Silicon-on-Insulator (SOI) wafers, produced by photolithography. We characterize the alignment effect of several patterns, including configurations that allow bistable director orientations. Also, the influence of a surface treatment (like deposition of a monolayer on the structured surface) is discussed.