METHOD FOR MANUFACTURING SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for manufacturing a semiconductor device is provided to improve punch-through caused by a short channel effect and hot carriers generated in a boundary between a gate and a drain, by forming a high density epi layer doped with the same conductivity type as a substrate on a channel region. CONSTITUTION: A predetermined portion of the first conductive semiconductor substrate(20) is eliminated to form a trench. The trench is filled with a semiconductor layer(22) highly doped with impurities of the first conductivity type. A gate(24) is formed in a predetermined portion of the semiconductor substrate including the trench by intervening a gate insulating layer(23). The second conductive doping region using the semiconductor layer of the trench as a channel region is formed in a predetermined portion of the semiconductor substrate.