ISOLATION STRUCTURE OF TRENCH AND METHOD FOR FORMING THE SAME

摘要

PURPOSE: An isolation structure of a trench and a method for forming the same are provided to restrain the diffusion of stress and impurities to a semiconductor substrate by improving the isolation structure within the trench. CONSTITUTION: A trench(140) is arranged on a predetermined region of a semiconductor substrate(100). A thermal oxide layer(150) is formed on an inner wall of trench(140). The thickness of the thermal oxide layer(150) is 110 angstrom. A lower liner pattern(161) is formed on an inner wall of the thermal oxide layer(150). A profile of the trench(140) is printed on the lower liner pattern(161) and the thermal oxide layer(150) since the lower liner pattern(161) and the thermal oxide layer(150) are arranged on the inner wall of the trench(140). Accordingly, the lower liner pattern(161) and the thermal oxide layer(150) has a U-shaped form, respectively. A lower isolation layer pattern(171) is formed within the trench(140). A U-shaped upper liner pattern(181) is formed on the lower isolation layer pattern(171). An upper isolation layer pattern(191) is formed on the U-shaped upper liner pattern(181).