A semiconductor device comprises an N-type insulated-gate field-effect transistor including a first insulating layer that is provided along side walls of a gate electrode, has a negative thermal expansion coefficient, and applies a tensile stress to a channel region of the N-type insulated-gate field-effect transistor. The device also comprises a P-type insulated-gate field-effect transistor including a second insulating layer that is provided along side walls of a gate electrode, has a positive thermal expansion coefficient, and applies a compression stress to a channel region of the P-type insulated-gate field-effect transistor.