FUNDAMENTAL CELL AND ARRANGEMENT STRUCTURE OF FUNDAMENTAL CELLS

摘要

PURPOSE:To use the upper and lower parts and the right and left parts symmetrically by a method wherein wells are formed symmetrically with respect to the upper and lower parts and the right and left parts, gate electrodes are formed on center lines which are symmetric with respect to the upper and lower parts and the right and left parts and the individual wells partitioned by the gates are used alternately as source regions and drain regions. CONSTITUTION:In a fundamental cell 40 composed of P-channel MOS-type transistors and a fundamental cell 42 composed of N-channel MOS-type transistors, the following are provided: wells 44, 46 whose shapes are symmetric with respect to the upper and lower parts and the right and left parts; and gate electrodes 48, 50 formed on center lines A1, A2, B1, B2 which are symmetric with respect to the upper and lower parts and the right and left parts of the wells. Individual partitions of the wells 44, 46 which are partitioned by the gate electrodes 48, 50 are used alternately as source regions 52A, 52B and drain regions 54A, 54B. That is to say, the PMOS-type transistors and the NMOS-type transistors are formed respectively in an upper and lower direction and in a right and left direction on gate formation faces of the wells. Thereby, the fundamental cells 40, 42 can be used symmetrically with respect to the upper and lower parts end the right and left parts.