METHOD FOR FORMING AN ISOLATING LAYER OF SEMICONDUCTOR DEVICES

摘要

PURPOSE: An isolating layer formation method of semiconductor devices is provided to prevent a generation of bird's beak without reducing an active region by reducing lattice matching between silicon substrate and nitride oxide layer. CONSTITUTION: The method comprises the steps of: forming a pad oxide(12) on a silicon substrate(11); transforming a first nitride oxide layer(12a) by annealing the pad oxide using N2 gas; depositing a nitride layer(13) on the first nitride oxide layer(12a); exposing a field region of the silicon substrate by etching the nitride layer(13); forming an oxide layer(14) by oxidation the exposed silicon substrate; transforming a second nitride oxide layer(14a) by annealing the oxide layer; implanting ions into the second nitride oxide layer(14a); forming a field oxide(15) by oxidation the second nitride oxide layer; and removing the nitride layer and the first nitride oxide layer.