Patent ID: 6563182
Filing Date: 2003-05-13
Classification: H01L

Abstract:
A semiconductor device comprising:a semiconductor substrate; a first MISFET including a first gate insulating film formed on said semiconductor substrate, wherein said first gate insulating film includes, at least in part, a first dielectric film containing first metal ions and having a relative dielectric constant of 8 or more; and a second MISFET including a second gate insulating film formed on said semiconductor substrate, wherein said second gate insulating film includes, at least in part, a second dielectric film containing second metal ions and having a relative dielectric constant of 8 or more; wherein first doping is performed on said first dielectric film using at least one kind of first impurity metal ions whose valence number differs by 1 from that of said first metal ions, and second doping is performed on said second dielectric film using at least one kind of second impurity metal ions whose valence number differs by 1 from that of said second metal ions, wherein at least one of the type and concentration differs between the first impurity metal ions and the second impurity metal ions, wherein due to said first and second doping, at least one of the density and polarity of charged defects differs between said first dielectric film and said second dielectric film, and wherein a threshold voltage difference between said first MISFET and said second MISFET is accomplished.