| 摘要 |
PURPOSE:To form a contact comprising of a structure in which a titanium nitride layer and a titanium silicide layer are laminated by mixing titanium atoms and substrate silicon atoms by ion implantations of two times through a contact hole over the titanium film. CONSTITUTION:Ion implantation of boron is performed over a titanium film 4. Only in a region 3 of contact hole, ions are implanted in an Si semiconductor substrate to form an implantation region 6. On that, some of titanium atoms in the titanium film 4 are mixed in the Si substrate by knock-on process at ion implantation by nitrogen ion implantation and a mixture layer 8 is formed. The nitrogen atoms are distributed with diffusion in the semiconductor substrate and the titanium film. By the nitrogen atoms diffused in the titanium film among them, the film 4 is changed into a titanium film 9 including nitrogen. Boron in the region 6 is activated by annealing and a P type diffusion layer 12 is formed. At the same time, the mixture layer 8 is converted into a titanium silicide layer 13 and further, the titanium film 9 is converted into a titanium nitride film 11. |
