A method of manufacturing an optical communication device aligns an optical sub-assembly and an optical modulator on a carrier wafer. A first sub-mount supports the optical sub-assembly and a second sub-mount supports the optical modulator. Pre-defined break lines are placed on the carrier wafer to accommodate separation of the sub-assembly and the optical modulator. The first sub-mount connects the optical sub-assembly to a thermoelectric cooler by either an epoxy, a spacer layer, or both. The optical sub-assembly is aligned in the x/y/z directions relative to the second sub-mount in a position to match an optical height of the optical modulator in the z-direction, wherein the z-direction is a vertical direction relative to the carrier wafer.