Method to reduce trench cone formation in the fabrication of shallow trench isolations

A method of forming trenches in the manufacture of an integrated circuit device comprising:

• forming a silicon dioxide layer overlying a semiconductor substrate;
• depositing a silicon nitride layer overlying said silicon dioxide layer;
• patterning said silicon nitride layer and said silicon dioxide layer to expose said semiconductor substrate where trenches are planned;
• implanting ions into said exposed semiconductor substrate to damage passive surface materials overlying said semiconductor substrate;
• and
• etching down said exposed semiconductor substrate to form trenches wherein said damaged passive materials are removed and the occurrence of trench cones is thereby reduced.

A method of forming shallow trench isolations in the manufacture of an integrated circuit device comprising:

• forming a silicon dioxide layer overlying a semiconductor substrate;
• depositing a silicon nitride layer overlying said silicon dioxide layer;
• patterning said silicon nitride layer and said silicon dioxide layer to expose said semiconductor substrate where shallow trench isolations are planned;
• implanting ions into said exposed semiconductor substrate to damage passive surface materials overlying said semiconductor substrate;
• etching down said exposed semiconductor substrate to form trenches wherein said damaged passive materials are removed and the occurrence of trench cones is thereby reduced;
• depositing a trench filling layer to fill said trenches;
• and
• polishing down said trench filling layer to complete said shallow trench isolations in the manufacture of said integrated circuit device.