SEMICONDUCTOR INTEGRATED CIRCUIT DEVICE AND FORMATION THEREOF

摘要

PURPOSE:To enhance an electrostatic breakdown strength by a method wherein an emitter region of a bipolar transistor is constituted by introducing antimony into a main-face part inside a region prescribed by an emitter opening of a base region. CONSTITUTION:Respective n-type emitter regions of bipolar transistors T1, T2 and an n-type semiconductor region 45 on one side of a MISFET Qs for memory selection use of a memory cell array MA form an opened impurity-introduction mask. Then, said impurity-introduction mask and an interlayer insulating film 54 at its lower layer are specified as an impurity-introduction mask; antimony (Sb) is introduced as n-type impurities by an ion implantation method. The n-type impurities which have been introduced into a main-face part of a p-type semiconductor region 42 of respective p-type base regions of the bipolar transistors T1, T2 form an n-type emitter region 56. A diffusion amount of Sb in a transverse direction of the emitter regions is large as compared with that of arsenic; even when a size of an emitter opening is increased by a precleaning operation executed before formation of a wiring part, it is possible to prevent a short circuit between the base regions and the wiring part.