Embodiments herein include an optical system that passively aligns an optical component (e.g., a fiber array connector, lens array, lens body, etc.) with a semiconductor substrate using trenches that mate with optical fiber stubs. In one embodiment, the trenches are etched into the semiconductor substrate which provides support to optical devices (e.g., lasers, lens arrays, photodetectors, etc.) that transmit optical signals to, or receive optical signals from, the optical component. An underside of the optical component is etched to include at least two grooves (e.g., V-grooves) for receiving optical fiber stubs. In one embodiment, the optical fiber stubs are a portion of optical fiber that includes the core and cladding but not the insulative jacket. Once the fiber stubs are attached to the grooves, the fiber stubs are disposed into the trenches in the semiconductor substrate thereby passively aligning the optical component to the optical device on the substrate.