SEMICONDUCTOR DEVICE AND ITS MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a semiconductor device having a trench type element isolating region easy in manufacturing process where the capacitance between adjacent elements is reduced and the stress is relaxed. SOLUTION: A buried insulation layer 2 and a semiconductor layer 3 are formed on a semiconductor substrate 1, and a field insulation film 6 having openings is formed on the semiconductor layer 3. Isolating trenches 4 pierce the semiconductor layer 3 located inside the opening of the field insulation film 6 and reach the buried insulation layer 2. An insulation film 7 is formed so as to cover the field insulation film 6 and above the isolating trenches 4 from their peripheries inwards like eaves. A side wall insulation film 5 is formed so as to close the openings of the insulation film 7 and involve voids 8 in the isolating trenches 4. COPYRIGHT: (C)2006,JPO&NCIPI