Being currently performed on highly complex and expensive equipments, active optical alignment of single mode 10 Gb/s transmitters and receivers is proving to be the bottleneck process for high volume manufacturing. In order to alleviate this production burden, new integrated technologies are required to align micro-components like micro-lenses and optical ﬁbers with photonic devices. Although passive alignment using Silicon micro-machined V- grooves seems to be very attractive at ﬁrst, it has only been successfully implemented for micro-lens which can tolerate up to several microns of misalignment. To resolve the latter issue, we propose a MEMS XY scanner mounted with a micro-lens to actively perform optical alignment of ﬁber optics modules by steering a beam. Although similar techniques have been demonstrated, we describe a unique technology using a 2x2.7 mm silicon bulk micro- machining chip characterized by ±30 µm XY range of motion, electrostatic comb drives actuation and a silicon hybrid lens with alignment locking capability. This thesis presents the design, fabrication and operation principle of an optical beam steerer for laser ﬁber coupling based on a MEMS device. The MEMS chip consists on a bi-dimensional movable platform based on uni-dimensional comb drive actuation. An optical lens is assembled onto the mobile platform to focus and steer the light coming from a laser diode and couple it into an optical ﬁber. Assembly of a complete system and measurements were performed and compared to simulation results. Both the tra jectory of the MEMS and resonance frequency measurements agree with the simulated ones.