A method of making an optical bench includes forming a trench in a substrate and wherein the trench has a sloping side, forming a reflector layer over the sloping side, depositing a redistribution layer over the substrate, disposing an under bump metallization (UBM) layer over the redistribution layer, depositing a passivation layer over the redistribution layer and surrounding sidewalls of the UBM layer, and mounting an optical component over an uppermost portion of the substrate, wherein the optical component is electrically connected to a through substrate via (TSV) extending through the substrate. The reflector layer is configured to reflect an electromagnetic wave from the optical component, and wherein the optical component is mounted outside the trench.