SEMICONDUCTOR INTEGRATED CIRCUIT

摘要

PURPOSE:To prevent the deterioration of signals on bit lines in high-speed operation by transferring signals through a twisted pair of bit lines formed in upper and lower layers on a substrate. CONSTITUTION:Upper bit lines 1 and 3 are formed above lower bit lines 2 and 4 on a substrate 11. Bit lines are connected through deviated contact holes 5 to form a pair of bit lines and a twisted pair of inverse bit lines. Bit line 201 and inverse bit lines 202 are connected to a sense amplifier 230 to amplify the very low voltage between the two lines. This realizes a smaller memory area than with a single-layer bit line structure and prevents the deterioration of signals on bit lines in high-speed operation.