Connection between optical fibers and optical components within a semiconductor substrate. A lens is created at the front of a semiconductor substrate. A tapered hole is created in the back of the substrate exposing part or all of the surface of the lens. An optical component is formed or affixed at the front surface of the substrate. A volume of transparent adhesive is placed in the hole, followed by an optical fiber, which is thus coupled to the surface of the lens. A light guide is created on the front of the substrate overlying the lens to direct optical signals between the optical fiber inserted in the tapered hole and the optical component on the surface of the substrate.