METHOD OF FORMING GATE OXIDE LAYER OF SEMICONDUCTOR DEVICE USING ION-IMPLANTATION FOR RESTRAINING GROWTH

摘要

PURPOSE: A method of forming a gate oxide layer of a semiconductor device is provided to simplify manufacturing processes and to prevent the moat by forming simultaneously gate oxide layers with different thicknesses within high and low voltage regions after implanting ions for restraining growth into the low voltage region. CONSTITUTION: A semiconductor substrate(201) with a high voltage device region and a low voltage device region is provided. An ion-implantation for restraining growth is performed on the low voltage device region. An oxidation is performed on the entire surface of the resultant structure. At this time, a thick gate oxide layer(206b) is formed on the high voltage device region and a thin gate oxide layer(206a) is formed on the low voltage device region.