C-MOS THIN FILM TRANSISTOR DEVICE AND MANUFACTURE THEREOF

PURPOSE:To enhance an n-type impurity concentration and to reduce n-ch source.drain part resistances by forming the upper layer part of the source.drain parts of a n-ch transistor in an n-type impurity high concentration region, and forming the lower layer part of the n-ch, p-ch source.drain parts and n-ch, p-ch gate electrodes in p-type impurity high concentration regions. CONSTITUTION:Polysilicon is deposited on a quartz board 1, and p-ch, n-ch active layers 2 are formed. Then a thermal oxide film 3 is grown on the surface of the polysilicon by thermally oxidizing. Then, polysilicon is deposited to form a gate electrode 4. In this case, a resist pattern 5 formed by a photolithography remains as it is. Thereafter, a resist 6 is formed on the p-ch, P ions 7 are implanted under predetermined conditions to form n-ch source.drain regions. Subsequently, after the whole resist is removed, B ions 9 are implanted under predetermined conditions to simultaneously form p-ch source.drain regions and implant impurity in the electrodes 4 of both transistors. Then, the ions are activated. Here, born 10 is controlled to be implanted in the upper layer of the layer 2 and the lower layer of phosphorus 8 to sufficiently lower sheet resistances of the source.drain parts.