A three-dimensional CMOS design methodology

A technology-updatable design methodology for three-dimensional CMOS circuits has been developed. Four levels of abstraction have been implemented with topographical congruence: (1) technology level, (2) mask level, (3) transistor level, and (4) logic level. A novel transistor-level symbolic representation is introduced which emphasizes the three-dimensional nature of the circuits. A number of design examples are presented.