Semiconductor device and a method for the manufacture thereof

A semiconductor device comprising:

• a conductivity-modulating region of a low concentration second conduction type formed on a cathode region of a high concentration second conduction type;
• a cathode electrode connected to the cathode region;
• at least one anode layer of a first conduction type located in the conductivity-modulating region;
• at least one anode electrode ohmically connected to the anode layer and coupled to the conductivity-modulating region to form a Schottky-junction at a Schottky-junction region of the conductivity-modulating region;
• and a floating region of the first conduction type coupled to the anode electrode via a MISFET;
• wherein the anode region includes at least two anode layers adjacent to the Schottky-junction region, and the MISFET is a first conduction-type MISFET which controls at least one of said anode layers and the floating region by using gate electrodes formed on gate oxide films located on a surface of the conductivity-modulating region.

A semiconductor device comprising:

• a conductivity-modulating region of a low concentration second conduction type formed on a cathode region of a high concentration second conduction type;
• a cathode electrode connected to the cathode region;
• at least one anode layer of a first conduction type located in the conductivity-modulating region;
• at least one anode electrode ohmically connected to the anode layer and coupled to the conductivity-modulating region to form a Schottky-junction at a Schottky-junction region of the conductivity-modulating region;
• and a floating region of the first conduction type coupled to the anode electrode via a MISFET;
• wherein the MISFET is a second conduction-type MISFET that is constructed in a well region of the first conduction type formed in the conductivity-modulating region, spanning an area of said anode region, and wherein connecting electrodes connected with the floating region are ohmically connected to the well region;
• and
• wherein the anode region includes at least two anode layers adjacent to the Schottky-junction region.

A semiconductor device comprising:

• a conductivity-modulating region of a second conduction type with a low concentration formed on a cathode region of the second conduction type with a high concentration;
• a cathode electrode connected to the cathode region;
• an anode region of a first conduction type formed in the conductivity-modulating region;
• anode electrode connected to the anode region by an ohmic junction;
• and a floating region of the first conduction type connected to the anode region by a MISFET;
• wherein the MISFET is a second conduction-type MISFET that is constructed in the well region of the first conduction type formed in the conductivity-modulating region in the vicinity of the anode region;
• and wherein electrodes connecting the MISFET of the second conduction type with the floating region include a Schottky-junction region that is Schottky-junctioned with the conductivity-modulating region around the floating region.