Lateral Schottky barrier diodes based on GaN/AlGaN 2DEG for sub-THz detection

This work presents results of investigations of lateral and vertical Schottky diodes based on Molecular Beam Epitaxy (MBE) grown GaN/AlGaN heterostructures. We have used plasma assisted molecular beam epitaxy in metal rich conditions on freestanding GaN commercial substrates and GaN/sapphire heterosubstrates. The optimized technological procedures have been used to avoid parasitic conduction channels through adjacent epitaxial layers, regrowth interface (RI) or conductive substrates. The investigated 2 dimensional electron gas (2DEG) epistructures were characterized using room temperature Hall measurements. The device processing was performed by using the laser writer technique and shallow mesa etching for electrical insulation of Schottky barrier diodes (SBDs). Our electrical measurements and first detection experiments performed in sub-THz confirm high quality of epitaxial layers, processing and possibility to use lateral SBD as high frequency (HF) detectors.