Being the field-effect transistor which was formed on the field-effect transistor and its formation mannered null substrate which have the crystal

摘要

The SOI transistor element and its production method are disclosed, point defect of the high density which locks is formed by including the territory in the active transistor territory which possesses the mismatch of the little lattice. With one concrete execution example, as for silicon germanium layer 320 it is offered to the active region. This active region has had the point defect of high density by easing the tension of silicon germanium layer by the fact that it heat-treats the transistor element. Recombination ratio increases very because of point defect, decreases the number of electric charge carriers which therefore are accumulated to the active region.