METHOD OF MANUFACTURING SEMICONDUCTOR STORAGE DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a method of manufacturing storage device which can form with higher accuracy a high impurity concentration region between source and drain. SOLUTION: A p+-type high concentration region 16 is formed between n+-type diffused regions 14a, 14b having the function to operate as the source/drain formed at the bottom of a trench 35 by implanting p-type impurity (boron B) in the direction n2 relatively forming the angle of about +/-45°to the normal nO of a silicon substrate 13 using, as the mask, silicon oxide films 31, 33 and silicon nitride films 32, 34 deposited on the top surface 12c of a projected area 12a formed on the p-type silicon substrate 13 by digging the trench 35 thereinto. Moreover, a high concentration region 16 is formed with higher accuracy because the lattice-to-lattice silicon in the silicon substrate 13 is reduced to control the redistribution of impurity when high temperature heat process is conducted before the process to implant such p-type impurity. COPYRIGHT: (C)2005,JPO&NCIPI