Transistor unit including shared gate structure, transistor circuit, and sub-word line driver and semiconductor device based on the same transistor unit

A transistor unit, a transistor circuit, a sub-word line driver and a semiconductor device are provided. The transistor with a shared gate structure includes an active area and a gate. The active area has a body extending in a first direction on a substrate, and a protrusion extending in a second direction perpendicular to the first direction from a central portion of the body in the first direction. The protrusion is divided into a first portion separated into two sub-portions by the separation area and a second portion, wherein the first portion is between the body and the second portion in the second direction. Opposite ends of the body in the first direction corresponding to two drain areas, the second portion of the protrusion corresponding to a common source area, and the gate constitute two transistors, wherein the two transistors share the gate.