GAP-FILL METHOD OF TRENCH HAVING HIGH ASPECT RATIO WITHOUT VOIDS IN SEMICONDUCTOR DEVICE

摘要

PURPOSE: A gap-fill method of a trench with high aspect ratio in a semiconductor device is provided to prevent voids by using an HDP(High Density Plasma) oxide layer. CONSTITUTION: A trench(24) is formed in a semiconductor substrate(21). A first He-based HDP oxide layer(27) is firstly deposited on the bottom and the side of the trench. An NF3-HDP oxide layer(28a) is formed on the first He-based HDP oxide layer. Annealing is performed to remove fluorine residues in the NF3-HDP oxide layer. A second He-based HPD oxide layer(29) is entirely filled in the trench.