Abstract
In some embodiments, the invention provides a semiconductor device, which includes a semiconductor substrate, and a supply layer arranged thereabove. The supply layer includes a top surface. A gate structure, a drain electrode and a source electrode are arranged above the supply later. A passivating layer, conformally, covers the gate structure and the supply later. A gate electrode is arranged above the gate structure. A field board is disposed on the passivating layer between the gate electrode and the drain electrode and includes a bottom edge. The gate electrode has a first edge being close to the field board. The field board includes a second edge which is faced to the first edge. Horizontal distance between the first and the second edges is 0.05-0.5 [mu]m. in the embodiments, the invention also provides a manufacturing method of the semiconductor device.