Selective epitaxy by beam energy and devices thereon

A method for the manufacture of a semiconductor device comprising the steps of:

• forming an insulating film on the surface of a semiconductor substrate having a predetermined conductivity type, the insulating film being selectively removed to form therein a window at a predetermined position;
• forming a semiconductor layer on the insulating film and the semiconductor substrate exposed through the window;
• melting the portion of the semiconductor layer corresponding to the window and the portion of the semiconductor substrate corresponding to the window by irradiation with an energy beam to a predetermined depth, by which an impurity in the semiconductor substrate is diffused into the semiconductor layer to impart thereto a predetermined conductivity type of relatively low impurity concentration and, at the same time, make monocrystalline at least that portion of the semiconductor layer corresponding to the window;
• and
• in the substrate is diffused into the semiconductor layer portion and the molten semiconductor layer portion is rendered to single crystalline.