| 摘要 |
PURPOSE:To obtain a P type Si gate FET by a method wherein, after the grain diameter of polycrystalline Si has been increased by performing an annealing using a laser beam or an electron beam, B is doped on the poly Si film located on an SiO2 film. CONSTITUTION:A film 9 is formed by performing selective etching on the poly Si layer located on an SiO2 film 8, and after the grain diameter of polycrystalline Si has been increased by performing a laser annealing, B is added to said film 9 by performing an ion implantation and, at the same time, a P-layer 7 is formed on an N type Si substrate 6. According to this constitution, grain diameter can be increased without using unnecessary impurities such as phosphor and the like, thereby enabling to form a P type Si gate MOSFET without generation of the punch-through of B. Also, the resistance of film can be reduced because the grain diameter is increased. |
