Manufacture of semiconductor device

Abstract

Abstract PURPOSE:To suppress a short-channel effect and to enhance an element characteristic by a method wherein second ions used to form a source/drain diffusion layer are implanted at an implantation angle which is smaller than the implantation angle used to form a first ion implanted region which has been made amorphous. CONSTITUTION:BF1<+> used to form source/drain diffusion layers is implanted into a silicon substrate 1 under a gate electrode 5 at an implantation angle theta2, e.g. 40 deg., which is smaller than the implantation angle theta1 of 50 deg. used to form a first ion implanted region 6. Thereby, a second ion implanted region 7 which is composed of a p<-> type low-concentration region 7a and a p<+> type high- concentration region 7b is formed in the first ion implanted region 6 which has been made amorphous. Then, the first and second ion implanted regions 6, 7 are heat-treated. Thereby, the first amorphous ion implanted region 6 is recrystallized and its crystallinity is restored; the second ion implanted region 7 which is composed of the low-concentration region 7a and the high- concentration region 7b is activated; the source/drain diffusion layers 8 which are composed of p<-> type low-concentration diffusion layers 8a and p<+> type high-concentration diffusion layers 8b are formed.

Inventors

• 👤 Naoyoshi Tamura
• 👤 直義 田村

Bibliographic Details