Method of forming a Al2O3 layer in a semiconductor device

PURPOSE: A method for manufacturing an aluminum oxide layer of a semiconductor device is provided to improve a characteristic intercepting penetration of hydrogen atoms, by simultaneously supplying NH3 process gas and aluminum source in forming the aluminum oxide layer. CONSTITUTION: Aluminum source and activation gas are simultaneously supplied to a process chamber in which a wafer is mounted, through separate lines. The remaining aluminum source and reaction byproducts are eliminated from the process chamber. Oxygen process gas is supplied to the process chamber. The remaining oxygen process gas is removed from the process chamber. The above-mentioned processes form one cycle for evaporating an aluminum oxide layer, and are repeated several times to form the aluminum oxide layer of a desired thickness.