An object is to realize high performance and low
power consumption in a
semiconductor device having an SOI structure. In addition, another object is to provide a
semiconductor device having a high performance
semiconductor element which is more highly integrated. A
semiconductor device is such that a plurality of n-channel field-effect transistors and p-channel field-effect transistors are stacked with an interlayer insulating layer interposed therebetween over a substrate having an insulating surface. By controlling a
distortion caused to a semiconductor layer due to an insulating film having a stress, a
plane orientation of the semiconductor layer, and a
crystal axis in a channel length direction, difference in mobility between the n-channel field-effect
transistor and the p-channel field-effect
transistor can be reduced, whereby current driving capabilities and response speeds of the n-channel field-effect
transistor and the p-channel field-effect can be comparable.