A compact semiconductor structure having back gate(s) for controlling threshold voltages and associated method of formation is disclosed. Fabrication of the semiconductor structure starts with a semiconductor region formed directly on an underlying electrically isolating layer. Then, a mandrel and a spacer are formed on the semiconductor region. Next, a back gate region is formed separated from the semiconductor region by a back gate isolating layer and covered by an inter-gate isolating layer. Next, a portion of the semiconductor region beneath the mandrel is removed so as to form an active region adjacent to the removed portion of the semiconductor region. Finally, a main gate region is formed in place of the removed portion of the semiconductor region and on the inter-gate isolating layer. The main gate region is separated from the active region by a main gate isolating layer and separated from the back gate region by the inter-gate isolating layer.
A static random access memory (SRAM) device a pair of cross-coupled, complementary metal oxide semiconductor (CMOS) inverters configured as a storage cell for a bit of data, a first pair of transfer gates configured to couple complementary internal nodes of the storage cell to a corresponding pair of bitlines during a read operation of the device; and a second pair of transfer gates configured to couple the storage cell nodes to the pair of bitlines during a write operation of the device, wherein impedance between the bitlines and the storage cell nodes during the write operation is less than that for the read operation, wherein impedance between the bitlines and the storage cell nodes during the write operation is less than that for the read operation.
