| 摘要 |
PURPOSE:To prevent the thermal distortion of a substrate and the occurrence of cracks on an insulating film by using an insulator, laser beam reflection layer, and poly Si multi-layer structure gate. CONSTITUTION:A gate electrode 14 on an si substrate 8 is of multi-layer structure of SiO2 11, Al12, and poly Si13. Ion implantation layers 9, 10 are made to activate by laser beams 15. At that time, the laser beams 15 penetrated the poly Si13 are completely reflected by the Al12 and will not reach the SiO211 or the substrate 8 and thermal treatment can be done. Therefore, the thermal distortion of the substrate or the occurrence of the cracks on the SiO211 can be prevented. Furthermore, the laser beams 15 arrived at Al12 reacts with the poly Si13 at the Al surface for alloy. In this composition, an insulating gate- type FET cab be obtained without adversely impacting characteristics by using a laser annealing method. |
