A semiconductor switching circuit device includes a field effect transistor having
a source electrode, a gate electrode and a drain electrode, a first electrode pad
connected to the source electrode or the drain electrode, and a second electrode
pad connected to the source electrode or the drain electrode which is not connected
to the first electrode pad. The device also includes a third electrode pad receiving
a DC voltage and applying the DC voltage to the field effect transistor, a first
insulating layer covering the field effect transistor, a metal layer disposed above
the first insulating layer and connected to the third electrode pad, and a second
insulating layer disposed on the metal layer. The third electrode pad may be a
control terminal pad, a ground terminal pad or a terminal pad receiving a constant
DC power voltage. The metal layer may be a flat sheet, a lattice or a comb-like structure.
