Patent ID: 6613634
Filing Date: 2003-09-02
Classification: H01L

Abstract:
A method for manufacturing a semiconductor integrated circuit device, comprising the steps of:(a) providing a semiconductor substrate having a memory cell forming region, in which memory cells are to be formed, the memory cells including MISFETs of a first conductivity type to be formed in first regions of the memory cell forming region and MISFETs of a second conductivity type, opposite to the first conductivity type, to be formed in second regions of the memory cell forming region; (b) covering the second regions of the memory cell forming region with resist films, the resist films having a thickness; and (c) introducing impurities into the memory cell forming region by oblique ion injection, in at least third and fourth directions, using the resist films as a mask, wherein thickness of the resist films, and angle of the oblique ion injection, are such that the impurities introduced by the oblique ion injection from the third and fourth directions are shielded from introduction into the first regions of the memory cell forming region, wherein said memory cell forming region is a region in which at least memory cells MC1 and MC2 are to be formed, and wherein impurities introduced by oblique ion injection in step (c) from the third and fourth directions are shielded by the resist films from introduction into the first regions of MC1 and MC2.