Contact holes of a different pitch in an application specific integrated

Abstract

In a first inter-layer insulator film above source/drain regions of basic cells constituting a gate array, first contact holes (joint contacts) are placed, so that wings (joint plates) electrically connected with the source/drain regions via plugs in those joint contacts is locally placed above the source/drain regions. Above the wings is formed a second inter-layer insulator film, above which is formed a first level interconnection which constitutes one of metal wiring layers. In the second inter-layer insulator film are formed second contact holes, so that a semi-custom ASIC is provided in which the wings and the first level interconnection are electrically interconnected via the plugs in those second contact holes. The first and second contact holes, first level interconnection, etc. are automatically designed by use of a computer based on a grid pattern in the basic cells. According to the present invention, the basic cells need not be re-designed even if a first pitch of a pattern of the first contact holes is different from a second pitch of a pattern of the second contact holes, thus easily enabling automatic customization. Without increasing the area of the source/drain regions in the basic cells, any pitch of the wiring layers can be selected, thus increasing the integration density without deteriorating the performance of MOS FETs at the same time as reducing time required for the customization.