An SRAM cell structure containing a PFET gate dielectric having a thicker effective oxide thickness (EOT) than an NFET gate dielectric and methods of manufacturing the same is provided. The PFET gate dielectric and the NFET gate dielectric may be silicon oxynitride layers, CVD oxide layers, or high-K dielectric layers having different thicknesses. The PFET gate dielectric may be a stack of two dielectric layers and the NFET gate dielectric may be one of the two dielectric layers. The greater EOT of the PFET gate dielectric produces reduction of the on-current of the pull-up PFETs for optimal SRAM performance.