A static random access memory (SRAM) cell structure is created in a
three-dimensional format as a vertical stack of wired transistors. These
transistors are fabricated from crystalline silicon, and supplemental
wiring structure features are fabricated to comprise a circuit along the
walls of a vertical pillar. The three-dimensional cell integrated circuit
can be created by a single mask step. Various structural features and
methods of fabrication are described in detail. Peripheral interface, a
two pillar version and other supplemental techniques are also described.