SEMICONDUCTOR DEVICE HAVING A GATE INSULATING LAYER OF A HIGH DIELECTRIC CONSTANT AND METHOD OF MANUFACTURING THE SAME

摘要

A semiconductor device and its manufacturing method are provided to secure the reliability by reducing a leakage current and a threshold voltage enough using an enhanced dual gate insulating layer structure composed of different material portions. A semiconductor device comprises a semiconductor substrate and first and second gate structures. The substrate(100) includes a first doped region and a second doped region. The first and second gate structures(107,117) are formed on the first and second doped regions, respectively. The first gate structure is composed of a first gate insulating layer(104) made of a first high-k dielectric material and a first gate electrode(106). The second gate structure is composed of a second gate insulating layer(114) made of a second high-k dielectric material and a second gate electrode(116).