Doping profiles in low resistive GaN tunnel junctions grown by metalorganic vapor phase epitaxy

We have systematically investigated acceptor (Mg) and donor (Si) profiles at GaN tunnel junction interfaces with the aim of a low resistivity under reverse bias. We found that an overlap between Mg and Si at the tunnel junction interface was effective in helping to obtain a lower resistivity of the GaN tunnel junctions, which contradicts the typical picture of conventional semiconductor-based tunnel junctions. We demonstrated a LED with the GaN tunnel junction prepared in a single growth run by metalorganic vapor phase epitaxy, showing a differential resistivity of 2.4 × 10 −4 Ω cm 2 at 5 kA cm −2 .