METHOD FOR MANUFACTURING MOSFET

摘要

PURPOSE: A fabrication method of an MOSFET is provided to enhance a property of a transistor such as a current(Ids) between a drain and a source and a snap-back-breakdown voltage at a GIDL(Gate Induced Drain Leakage) structure. CONSTITUTION: A field oxide layer(2) and an oxide layer for a buffer are formed on a substrate(1) and an ion for controlling a threshold voltage is implanted thereon. The oxide layer is removed and a mask of an insulating layer is formed on the substrate for forming a source region and a gate electrode(3). A first gate oxide layer is grown on the exposed substrate and the mask is removed. A second gate oxide layer is grown to have a thin thickness than a thickness of the first gate oxide layer. The gate electrode(3) is formed, so that both sides of the gate electrode are located at a boundary of the first gate oxide layer and the second gate oxide layer respectively. A source/drain region(5) of a second conductive type is formed on the substrate of both side of the gate electrode.