A Novel High Speed, Three Element Si-Based Static Random Access Memory (SRAM) Cell

A novel three element SRAM cell consisting of a gate, a load, and a bistable SiGe/Si diode as the storage element is proposed and demonstrated with a test structure. Containing two closely-spaced delta-doped layers and a SiGe/Si strained superlattice, the diode exhibits two stable states with a conductance contrast of over six orders of magnitude, which of fers the possibility for the new cell to operate with a low power dissipation. Because the size of the diode can be as small as the design rules allow, the cell area will be comparable with that of the conventional DRAM cell. The high speed operation mechanism of the diode also provides a potential application for high speed SRAM using this cell.