MOS FIELD-EFFECT TRANSISTOR COMPRISING LAYERED STRUCTURE INCLUDING Si LAYER AND SiGe LAYER OR SiGeC LAYER AS CHANNEL REGIONS

摘要

PURPOSE: To improve electron and hole mobilities in a channel party by employing a distorted Si/SiGe structure (or distorted Si/SiGeC structure), to keep the crystallinity of such a heterostructure in a proper condition, to prevent shortening of an effective channel length and diffusion of a Ge, and to reduce the resistance of the source layer and chain layer. CONSTITUTION: An MOS field effect transistor is constructed, in such a manner that a channel region has a laminated structure formed in the order of an Si layer (2) and an SiGe or an SiGe layer (3), a source layer (4) and a drain layer (5), which is formed of an SiGe or SiGeC containing high concentration impurity atoms which are formed by low-temperature chemical vapor deposition method and provides a desired conductive shape, contract with both ends of the channel region and the surfaces of the source and drain layers formed of the SiGe or the SiGeC are shaped so as to be raised upward from the bottom position of a gate electrode (6).