Trench isolation type semiconductor device and related method of manufacture

A method of manufacturing a semiconductor device, the method comprising:

• forming a trench in a semiconductor substrate;
• sequentially forming a first oxide film and a nitride film on an upper surface of the semiconductor substrate and on an inner wall of the trench;
• forming a field insulating film to fill the trench;
• selectively removing portions of the nitride film to form a nitride liner having an exposed upper end portion, expose side surfaces of the first oxide film, expose the first oxide film on the upper surface of the semiconductor substrate, and expose a portion of the first oxide film formed on a corner portion of the semiconductor substrate through a first recess;
• forming a first field protecting film to cover the exposed upper end portion of the nitride liner and fill the first recess;
• selectively removing portions of the first oxide film to expose upper surface and the corner portion of the semiconductor substrate, and portions of the exposed side surfaces of the first oxide film to form a second recess;
• forming a second oxide film thinner than the first oxide film on the exposed corner portion of the semiconductor substrate to partially fill the second recess;
• and
• forming a second field protecting film to fill the residual portion of the second recess.

A method of manufacturing a semiconductor device, the method comprising,

• forming a trench in a semiconductor substrate;
• sequentially forming a first oxide film and a nitride liner on an inner wall of the trench;
• forming a field insulating film on the nitride liner to fill the trench, wherein a side surface of the field insulating film, an upper end portion of the nitride liner, an upper end portion of the first oxide film, and an exposed corner portion of the semiconductor substrate form a trench edge recess;
• forming a second oxide film thinner than the first oxide film on the exposed corner portion of the semiconductor substrate to partially fill the trench edge recess;
• and
• forming a field protecting film to fill the residual portion of the trench edge recess.