Semiconductor device and method for fabricating the device

摘要

A first gate electrode for an n-channel MOSFET includes first and second metal films and a low-resistivity metal film. The first metal film has been deposited on a first gate insulating film and is made of a first metal having a work function located closer to the conduction band of silicon with reference to an intermediate level of silicon bandgap. The second metal film has been deposited on the first metal film and is made of a second metal having a work function located closer to the valence band of silicon with reference to the intermediate level of silicon bandgap. The low-resistivity metal film has been deposited on the second metal film. A second gate electrode for a p-channel MOSFET includes: the second metal film, which has been deposited on a second gate insulating film and is made of the second metal; and the low-resistivity metal film deposited on the second metal film.