A shadow mask having two or more levels of openings enables selective step coverage of micro-fabricated structures within a micro-optical bench device. The shadow mask includes a first opening within a top surface of the shadow mask and a second opening within the bottom surface of the shadow mask. The second opening is aligned with the first opening and has a second width less than a first width of the first opening. An overlap between the first opening and the second opening forms a hole within the shadow mask through which selective coating of micro-fabricated structures within the micro-optical bench device may occur.