Semiconductor device

A semiconductor device comprising:

• a support substrate including a silicon layer in which a diode is formed, the silicon layer including a cathode layer of a first conductivity type and an anode layer of a second conductivity type;
• a component substrate including
• a first semiconductor layer disposed on the support substrate and made of a first gallium nitride based semiconductor to define a drift region, and
• a second semiconductor layer disposed on the first semiconductor layer and made of a second gallium nitride based semiconductor that has a band gap energy larger than that of the first gallium nitride based semiconductor;
• a source electrode disposed on the second semiconductor layer and having
• a source wiring portion extending in a second direction, and
• a plurality of source comb-teeth electrodes protruding from the source wiring portion in a first direction, wherein the first direction being one direction in a surface direction of the component substrate and intersecting the second direction;
• a drain electrode disposed on the second semiconductor layer and having
• a drain wiring portion extending in the second direction, and
• a plurality of drain comb-teeth electrodes protruding from the drain wiring portion in the first direction, the drain comb-teeth electrodes and the source comb-teeth electrodes being arranged alternately in the second direction;
• a gate electrode having a gate comb-teeth electrode arranged between the source comb-teeth electrode and the drain comb-teeth electrode in the second direction;
• a source through via formed in the component substrate and electrically connecting the anode layer and the source electrode;
• and
• a drain through via formed in the component substrate and electrically connecting the cathode layer and the drain electrode, wherein
• the cathode layer and the anode layer are arranged in the first direction,
• the cathode layer is located to include a position opposing the drain wiring portion in a stacking direction of the support substrate and the component substrate,
• the anode layer is located to include a position opposing the source wiring portion in the stacking direction,
• the source through via is arranged to connect the source wiring portion and the anode layer, and
• the drain through via is arranged to connect the drain wiring portion and the cathode layer.