SEMICONDUCTOR DEVICE WITHOUT INVERSE NARROW CHANNEL EFFECT AND MANUFACTURING METHOD THEREOF

摘要

PURPOSE: A semiconductor device and a manufacturing method thereof are provided to restrain effectively inverse narrow channel effect by forming a second semiconductor layer containing predetermined impurities on a first semiconductor layer within a trench. CONSTITUTION: A trench(10) is formed in a semiconductor substrate(1). An isolation layer(2) is filled in the trench. A first semiconductor layer(4) is formed along sides of the trench. A second semiconductor layer(5) is formed on the first semiconductor layer within the trench region. The second semiconductor layer contains predetermined impurities of the same conductive type as a channel region of a predetermined transistor. The first semiconductor layer is capable of restraining the predetermined impurities of the second semiconductor layer from being diffused due to a heat treatment.