Low stress semiconductor devices with thermal oxide isolation

A semiconductor device including:

• a semiconductor substrate;
• a plurality of circuit regions formed on device formation regions in said semiconductor substrate;
• and
• device isolation regions provided as grooves each groove having a depth, extending inwardly from a main surface of said semiconductor substrate, greater than 6 nm formed before thermal oxide film formation thereof as to isolate said plurality of circuit regions from one another on said semiconductor substrate, and each device isolation region having a width of 0.1 to 2.5 μm,
• wherein a width of each of the circuit regions is set such that a ratio of the width of a circuit region to the width of an adjacent device isolation region is at least 2 and not greater than 50 to prevent stress in the substrate from exceeding a dislocation occurrence limit stress value which is otherwise likely to occur, based on the depth of the grooves exceeding 6 nm to cause a dislocation at portions of the main surface of the substrate located adjacent mask ends of a mask used to form the grooves.

A semiconductor device including:

• a semiconductor substrate;
• a plurality of circuit regions formed on device formation regions in said semiconductor substrate;
• and
• device isolation regions provided as grooves each groove having a depth, extending inwardly from a main surface of said semiconductor substrate, greater than 6 nm formed before thermal oxide film formation thereof so as to isolate said plurality of circuit regions from one another on said semiconductor substrate, and each device isolation region having a width of 0.1 to 2.5 μm,
• wherein a width of each of the circuit regions is set such that a ratio of the width of a circuit region to the width of an adjacent device isolation region is at least 2 and not greater than 50, whereby the semiconductor device will be substantially free of dislocations which would otherwise be likely to occur, based on the depth of the grooves exceeding 6 nm, at portions of the main surface of the substrate located adjacent mask ends of a mask used to form the grooves.