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The efficiency of laserdiode-monomode fiber coupling is one of the essential assignments for interactive optical telecommunications. In this paper, we present our investigations and results of the development of such couplers, especially of a soldering process for hybridly joining a laser on a silicon microoptical bench by selfadjustment.To achieve the necessary adjustment tolerances of better than 0.5 tm, the influence of the solder height for the selfalignment process is simulated with respect to the lowest allowable solder thickness, which still generates the necessary alignment forces. Because of the excellent properties at their coupling facet U-grooves were fabricated to mount the fiber by deep and high precision anisotropic reactive ion etching (TIlE) of silicon using SF6/CBrF3 gas-mixtures. The solder was deposited in buried structures by electroplating gold and tin at the eutectic ratio (80/20) to allow optimum adjustment in vertical and lateral dimensions. Furthermore, the results of a fiuxiess soldering process in an UV-light activated forming gas atmosphere is presented and compared to the simulations. The measurement of the coupling efficiency to fibers will also be illustrated. The design of the micro optical bench allows to extend the system by incorporating e.g. a faraday rotator or other optoelectronic integrated circuits (OEICs) , like transceivers.