US Patent 11282842 Memory device and manufacturing method

A static random access memory device includes a first gate, a second gate, and a third gate. The first gate extends in a first direction from a standard threshold voltage region of a substrate to a low threshold voltage region, abutting the standard threshold voltage region, of the substrate. The second gate is disposed in the standard threshold voltage region of the substrate. The third gate is disposed in the low threshold voltage region of the substrate. The standard threshold voltage region has a boundary at an edge of the second gate. The boundary extends in a second direction different from the first direction and is crossed by the first gate. A distance between the boundary and the first gate is different from a distance between the boundary and the second gate.