Patent ID: 8314449

Claim:
A CMOS device having an n-channel MOS transistor and a p-channel MOS transistor formed in a semiconductor substrate having a surface with a principal crystal plane, wherein said n-channel MOS transistor comprises a first gate insulator film formed on a flat portion of said surface of said semiconductor substrate having an electron mobility, μ n1 , a first gate electrode formed on said first gate insulator film so as to be elongated in the direction of a gate length, L A , and in the direction of a gate width, W A , and a pair of n-type regions formed in said semiconductor substrate on both sides of said first gate electrode in the direction of said gate length, wherein said p-channel MOS transistor comprises a projecting part formed on said semiconductor substrate and directly projecting from the surface of said semiconductor substrate, at least one of a top surface of width W 1B having a hole mobility μ p1 , and a side wall of said projecting part of height H B , having a secondary crystal plane different from said principal crystal plane and having a hole mobility μ p2 , a top plane of said projecting part is the (100) crystal plane and a side wall plane of said projecting part is the (110) crystal plane, a second gate insulator film formed on said semiconductor substrate including said projecting part in such a way that said second gate insulator film covers at least a portion of said semiconductor substrate of width W 2B , said top surface and said side wall of said projecting part, a second gate electrode formed on said second gate insulator film so as to be elongated in the direction of a gate length, L B , and in the direction of a gate width, W B , a pair of p-type regions formed in said semiconductor substrate including said projecting part on both sides of said second gate electrode in the direction of said gate length; and wherein said semiconductor substrate is a silicon substrate, and said principal crystal plane is the (100) crystal plane, and said secondary crystal plane is the (110) crystal plane; wherein for W A =W 1B +W 2B and L A =L B , H B is effectively set such that μ n1 W A =μ p1 (W 1B +W 2B )+2μ p2 H B .