US Patent 8942030 Structure and method for SRAM cell circuit

The present disclosure provides a static random access memory (SRAM) cell. The SRAM cell includes a first and a second pull-up devices; a first and a second pull-down devices configured with the first and second pull-up devices to form two cross-coupled inverters for data storage; and a first and second pass-gate devices configured with the two cross-coupled inverters to form a port for data access, wherein the first and second pull-down devices each includes a first channel doping feature of a first doping concentration, and the first and second pass-gate devices each includes a second channel doping feature of a second doping concentration greater than the first doping concentration.