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We studied the possibilities of LTCC (low temperature cofired ceramics) technology to fabricate fiber-pigtailed transmitter arrays using surface-emitting sources, such as VCSELs, equipped with vertical-mounted multimode fiber pigtails. The designed LTCC module can be mounted vertically on a printed-circuit-board (PCB), thus providing small, essentially one-dimensional PCB footprint. The fiber is aligned and supported using a hole structure through the layers, and the light source is flip-chipped on the other side of the substrate. Thus, this kind of fiber pigtailed module allows for the use of detachable electrical interface between the fiber optic media and applications electronics. Therefore, in this case, the alignment tolerances required for the connections are looser than when using conventional optical connections. In addition, the small size of the module increases the positioning freedom of transmitter and receiver modules on PCBs.To evaluate the feasibility of the system, a 4-layer LTCC substrate for a 5-channel transmitter was designed and realized using VCSEL chips and 62.5/125-micron fibers. Each transmitter, sized 5 mm × 5 mm, included discrete passives and a laser-driver chip. Metallic tubes were used as strain relief boots for the fiber assembly, and the substrate was mounted vertically on a test board. Optical alignment tolerances were examined by measurements and simulations, and the tolerances of fiber-mounting holes were evaluated by preparing test structures. The alignment accuracy seemed adequate even for the first prototypes. Nevertheless, stringent requirements for the LTCC process control are necessary to achieve the needed accuracy.