METHOD FOR FABRICATING SEMICONDUCTOR DEVICE TO EFFECTIVELY IMPROVE SHORT CHANNEL EFFECT AND REVERSE SHORT CHANNEL EFFECT

摘要

PURPOSE: A method for fabricating a semiconductor device is provided to effectively improve a short channel effect and a reverse short channel effect by performing an N ion implantation process after a gate is formed so that a thick oxide layer is grown on the sidewall of a gate poly in a subsequent re-oxidation process and by using the thick oxide layer as an ion implantation barrier in an LDD(lightly doped drain) ion implantation process. CONSTITUTION: A gate(5) of a silicon material is formed on an active region of a silicon substrate(1) confined by an isolation layer(2). An N ion implantation process is performed to slow down an oxidation speed in the gate and the substrate. A gate re-oxidation process for removing etch damage in forming the gate is performed to grow an oxide layer(6) of the first thickness in the surface of the substrate and the gate while an oxide layer of the second thickness greater than the first thickness is grown on the sidewall of the gate. An LDD ion implantation process is performed on the front surface of the substrate. A nitride layer is deposited on the resultant structure. The nitride layer and the oxide layer are blanket-etched to form a spacer on both sidewalls of the gate. A source/drain ion implantation process is performed on the front surface of the substrate. The resultant structure is annealed to form a source/drain region having an LDD region in the surface of the substrate at both sides of the gate.