| 摘要 |
PURPOSE:To obtain high-speed MOSFET's in the simple process by eliminating the dimensional variation between the inside of a wafer and the wafer at the side wall by a method wherein a drain of light-doped drain (LDD) structure is formed by self-alignment. CONSTITUTION:After a field region 4 and a gate oxide film 5 are formed on a semiconductor substrate 3 by a prescribed method, a Ti film 18 is adhered thereon by the CVD method, and a polycrystalline Si film 19 is formed; thereafter, an impurity is diffused into the film 19. Next, the gate section 8 of a three-layer of the films 19, 18, and 5 is formed by etching, and ions 15 are implanted. An N<+> diffused region 9 is formed by this implantation of ions 15, and an oxide film 20 is formed on the region 9. At this time, an oxide film 19a and an oxide film 21 are formed at the same time, and further eaves 22 are formed on the side end 23 at both ends of the film 18a. Ions 17 under a required pressure in a required amount are implanted by using the film 21 having the eaves 22 as a mask, thus forming an N<+> diffused region 12, resulting in the elimination of the dimensional variation inside the side wall 23 and therebetween. |
