METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for manufacturing a semiconductor device is provided to simplify processes by forming a channel area having different threshold voltages, respectively, by performing an ion injection for controlling threshold voltage after forming a buffer dielectric layer, each having different thickness on a semiconductor substrate. CONSTITUTION: A method for manufacturing a semiconductor device includes a first through third steps. The first step is to form a first buffer dielectric layer(33) on the surface of a first active area(B1) and a second buffer dielectric layer(32) having thicker than the first buffer dielectric layer on the surface of a second active area(B2) after defining the first active area and the second active area on a semiconductor substrate(31). The second step is to perform an ion injection for controlling a threshold voltage on the first and second buffer dielectric layers. The third step is to delete the first and the second buffer dielectric layers.