Semiconductor switches with evenly distributed fine control structures

A semiconductor switch having a substantially non-doped monolithic semiconductor crystal for switching currents in two directions and suitable for blocking voltages which are significantly higher than operating voltages of gate circuits,

• said switch comprising an active portion and a termination portion wherein opposite surfaces of the active portion are provided with fine structures (10, 11, 12, 13, 14) which are distributed over wide lateral areas,
• said fine structures are substantially uniformly configured and including conductive terminal surfaces and control surfaces (GA, GB) for moving charge carriers in a controlled manner out of the active portion of the semiconductor crystal, thus controlling a concentration of the charge carriers in the active portion and providing an off-state of the semiconductor switch.

A semiconductor switch having at most a weakly doped semiconductor crystal for switching currents in two directions at voltages which are significantly higher than operating voltages of gate circuits, comprising:

• an active region (1) and a termination portion (50, 51), wherein the semiconductor switch in the active region (1) comprises, close to the surface, two opposite surfaces of the active region (1) and a plurality of fine structures (10, 11, 12, 13, 14) distributed over a wide area,
• the structures being substantially uniformly configured and having a conductive terminal surface (KA, KB), said distributed fine structures absorbing and supplying charge carriers, for controlling through associated conductive control surfaces (GA, GB) the charge carriers to the active region (1) of the semiconductor crystal for switching the current to an on state, and from the active region for switching the current to an off state.