METHOD FOR MANUFACTURING STI STRUCTURE WITH AIR GAP

摘要

PROBLEM TO BE SOLVED: To provide a method for manufacturing a shallow trench isolation structure (STI) with an air gap formed by decomposing a polymer filler material through an air gap layer. SOLUTION: A pad layer 20 and a barrier layer 30 are formed on a substrate, these pad layers are patterned so as to form a trench opening and are etched through the trench opening and a trench 12 is formed on the substrate 10. A first linear layer 32 is formed on a sidewall of the trench 12 and a second liner layer 34 is formed on the barrier layer 30 and the first liner layer 32. A filler material is formed on the second liner layer 34 and a cap layer 50 is deposited on these layer 34 and the filler material, the filler material is heated so as to evaporate by reacting with a plasma and the air gap 60 is formed by diffusing through the cap layer 50. An insulation film 70 is deposited on the cap layer 50, the insulation layer 70 is planarized and the barrier layer 30 is removed.