MANUFACTURE OF SEMICONDUCTOR DEVICE

• Main Author: SASAKI TAKAE
• Format: Patent
• Language: English
• Published: 07.02.1992
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; SEMICONDUCTOR DEVICES

PURPOSE:To reduce protruded and recessed areas at the etching surface and alleviate concentration of stress at the trench corner area by forming a groove to the area in which an element isolating region of a semiconductor substrate is to be formed, then implanting oxygen ion to such groove and thereafter forming an oxide film by the heat treatment. CONSTITUTION:A groove 14 is formed to the area wherein an element isolating region of a semiconductor substrate B is to be formed, next oxygen ions one implanted to such groove 14 and thereafter an oxide film 16 is formed to an oxygen ion implanting region 15 by the heat treatment. For instance, the trench etching is carried out, by the RIE method, to the semiconductor substrate B consisting of a single crystalline Si layer 11, a doped Si layer 12 and an epitaxial Si layer 13 to form a U-shaped groove 14. When the oxygen ions one implanted to the substrate B with an inclination angle of 10 to 60 degrees from the perpendicular direction while the substrate B is rotating, the side wall of groove 14 is flattened and an amorphous layer 15 including large amount of oxygen is formed, where the corner is rounded and the bottom part is thick. Thereafter, annealing is conducted at 800 to 900 deg.C and an oxide film 16 showing strong bonding strength can be formed at the external surface of groove.