| 摘要 |
PROBLEM TO BE SOLVED: To solve the problem wherein a gate insulating film and a semiconductor are attacked to deteriorate the characteristics and reliability of an insulated gate field effect transistor when a gate electrode whose work function varies in the direction of channels is formed. SOLUTION: A part of an impurity region which is formed in a semiconductor 4 where channels are formed and located on the side of a source region 8 is covered with a thick insulating film 10, and a gate insulating film 11 is formed on a channel forming region to form a level difference. A first conductive layer 12 is formed, a protective layer 13 is formed on each of parts opposed to the sides of the level difference, and a second conductive layer 14 is formed. Thereafter, a process is provided to modify a part of the first conductive layer 12 coming into contact with the second conductive layer 14, and to set a work function difference between the non-modified part 12a of the first conductive layer 12 which is protected by the protective layer 13 and the channel forming region different from that between the modified part 12b of the first conductive layer 12 and the channel forming region above the region. COPYRIGHT: (C)2004,JPO
|
