An energy beam source presented is for use in micro-fabrication tasks, such as fabrication of specific patterns, in-situ bonding, repair, connection and disconnection of electrical paths, applicable to semiconductor devices and other micro-sized circuits in integrated circuits. The beam source is made compact so that several sources can be located inside a vacuum vessel and in conjunction with micro-manipulators or micro-movement stages operated under light or electron microscope. The beam source is provided with at least three electrodes, and by applying a selected voltage, i.e., high frequency voltage, direct current voltage and ground voltage, on each the three electrodes in association with film-forming substance(s), virtually any type of deposit can be formed in any location of the workpiece. Different types of particle beam, such as positive and negative ion beams, highspeed neutral atomic beam, radical particle beam, electron beam can be produced from the beam source by judicious choice of operating parameters and the film-forming material which may be a process gas or an applied coating. By using the beam source and the method of deposit forming presented, virtually any type of fabrication tasks can be carried out on any surface and any location of a workpiece in a three-dimensional space. The availability of the compact energy beam source is expected to open a new path to such leading-edge industries as repair of semiconductor devices, circuit alteration/repair and micro-machining of ultrasmall components for various fields.