Method and apparatus for improving read margin for an SRAM bit-cell

摘要

Described is a 6T SRAM cell which comprises: a first n-type transistor with a gate terminal coupled to word-line, source/drain terminal coupled to a first bit-line and drain/source terminal coupled to a first node; and a second n-type transistor with a source terminal coupled to a first supply node, a drain terminal coupled to the first node, and a gate terminal for coupling to multiple terminals, wherein the gate terminal includes a capacitor to increase coupling capacitance of the second n-type transistor. Described is a method which comprises: forming a metal gate in a first direction; forming a first spacer in the first direction on one side of the metal gate, the first spacer having a first dimension; and forming a second spacer in the first direction on another side of the metal gate, the second spacer having a second dimension which is substantially different from the first dimension.