| 摘要 |
PROBLEM TO BE SOLVED: To prevent a variation in the threshold voltage of a p-channel MIS transistor by preventing p-type impurities in a p-type silicon layer employed in a gate electrode from being diffused into an underlying semiconductor substrate through a gate insulation film when a high dielectric film is employed as the gate insulation film. SOLUTION: A high dielectric film 3 is formed on a silicon substrate 1 and the surface of the high dielectric film 3 is nitrided using radical nitrogen thus forming a nitride layer 4. A gate electrode 5 including a p-type polysilicon layer doped with boron is then formed on the nitride layer 4. The entirety of the high dielectric film 3 and the overlying nitride layer 4 constitutes a gate insulation film 3. Subsequently, p<SP>+</SP>type source region 8 and drain region 9 are formed while being self-aligned with the gate electrode 5 thus forming a p-channel MIS transistor. COPYRIGHT: (C)2004,JPO
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