Multi-channel HEMT

A semiconductor device, comprising:

• a semiconductor heterostructure including a plurality of alternating two-dimensional electron gasses (2DEGs) and two-dimensional hole gasses (2DHGs) extending in parallel at different depths in the semiconductor heterostructure and which are formed by positive and negative polarization charges that build up at different depths in the semiconductor heterostructure;
• a first doped region disposed in the semiconductor heterostructure in contact with the 2DEGs;
• a second doped region spaced apart from the first doped region in the semiconductor heterostructure and in contact with the 2DEGs;
• and
• a plurality of spaced trench structures extending into the semiconductor heterostructure so that regions of the heterostructure are disposed between adjacent ones of the trench structures, each trench structure comprising an insulating material lining sidewalls and a bottom of the trench structure and an electrically conductive material separated from the surrounding semiconductor heterostructure by the insulating material,
• wherein the trench structures are spaced apart from one another in a direction perpendicular to a current flow direction of the semiconductor device so that current flows around and between the trench structures through regions of the semiconductor heterostructure disposed between adjacent ones of the trench structures via the 2DEG current channels when the semiconductor device is biased in an on-state,
• wherein the trench structures are configured to deplete the 2DEG current channels from the sides of the trench structures in the regions of the semiconductor heterostructure disposed between adjacent ones of the trench structures.