Semiconductor device and method for manufacturing the same

A semiconductor device, comprising:

• a substrate having a plurality of first-type doped semiconductor regions and second-type doped semiconductor regions alternately arranged;
• a first nitride-based semiconductor layer disposed over the substrate;
• a second nitride-based semiconductor layer disposed on the first nitride-based semiconductor layer and having a bandgap greater than a bandgap of the first nitride semiconductor layer;
• a pair of first source/drain (S/D) electrodes disposed on the second nitride-based semiconductor layer;
• a first gate electrode disposed on the second nitride-based semiconductor layer and between the first S/D electrodes;
• a pair of second S/D electrodes disposed on the second nitride-based semiconductor layer;
• a second gate electrode disposed on the second nitride-based semiconductor layer and between the second S/D electrodes;
• a first interconnection disposed over the second nitride-based semiconductor layer and penetrating the first and second nitride-based semiconductor layers to form a first interface with at least one of the doped semiconductor regions;
• and
• a second interconnection disposed over the second nitride-based semiconductor layer and penetrating the first and second nitride-based semiconductor layers to form a second interface with at least one of the doped semiconductor regions, wherein the first interface is spaced apart from the second interface, and wherein a vertical projection of a portion of the first nitride-based semiconductor layer on the substrate is between the first and second interfaces and at least spans across a whole one of the first and second type doped semiconductor regions.

A method for manufacturing a semiconductor device, comprising:

• forming a plurality of first type doped semiconductor regions and second type doped semiconductor regions with a plurality of heterojunctions in a substrate;
• forming a first nitride-based semiconductor layer above the substrate;
• forming a second nitride-based semiconductor layer on the first nitride-based semiconductor layer, wherein the second nitride-based semiconductor layer has a bandgap greater than a bandgap of the first nitride-based semiconductor layer;
• forming a pair of first source/drain (S/D) electrodes and a pair of second S/D electrodes on the second nitride-based semiconductor layer;
• forming a first gate electrode and a second gate electrode on the second nitride-based semiconductor layer, wherein the first gate electrode is present between the first S/D electrodes and the second gate electrode is present between the second S/D electrodes;
• removing portions of the first nitride-based semiconductor layer and the second nitride-based semiconductor layer to form a first trench and a second trench separated from each other, so as to expose a top portion of the substrate;
• and
• forming first and second interconnections in the first and second trenches, respectively, and in contact with the top portion of the substrate so as to form a first interface and a second interface, wherein vertical projections of the first and second interfaces on the substrate are at least separated from each other by at least two of the junctions.