Method of forming a trench for use in manufacturing a semiconductor device

A method of forming an isolation film for use in manufacturing of a semiconductor device, said method comprising:

• forming a photoresist pattern on a substrate;
• performing a first etching process comprising etching the substrate using the photoresist pattern as a mask to form an initial trench in the substrate;
• subsequently performing a second etching process that is distinct from said first etching process, said second etching process comprising etching the substrate in which the initial trench is already formed to thereby enlarge the initial trench;
• and
• subsequently forming an oxide film that fills the enlarged trench.

A method of forming a conductive pattern for use in manufacturing a semiconductor device, said method comprising:

• forming an insulation film on a substrate;
• forming a photoresist pattern on the insulation film;
• performing a first etching process comprising etching the insulation film using the photoresist pattern as a mask to form an initial trench in the insulation film;
• and
• subsequently performing a second etching process that is distinct from said first etching process, said second etching process comprising etching the insulation film in which the initial trench is already formed to thereby enlarge the initial trench;
• and
• depositing a conductive material in the enlarged trench to form a conductive pattern in the insulation film.

A method for manufacturing a semiconductor device comprising:

• forming a first insulation film on a substrate;
• forming a first conductive pattern in the insulation film;
• forming at least one etch stop layer and at least one second insulation film in the foregoing sequence on the first insulation film;
• forming a first photoresist pattern on the second insulation film;
• etching the etch stop layer and the second insulation film using the first photoresist pattern as a mask to from a via hole that exposes the first conductive pattern by removing the first photoresist pattern;
• subsequently forming a second photoresist pattern on the second insulation film, the second photoresist pattern having an opening aligned with the via hole;
• etching the etch stop layer and the second insulation film using the second photoresist pattern as a mask to thereby form an initial trench aligned with the via hole;
• subsequently etching the second insulation film to enlarge the initial trench;
• and
• depositing a conductive material in the via hole and in the enlarged trench to thereby form a second conductive pattern and a third conductive pattern in the via hole and in the enlarged trench, respectively.