Achieving Face-Selective Ohmic Contact to β-Ga 2 O 3 via Anisotropic Trench Structure

High Resolution Image Download MS PowerPoint Slide Achieving low contact resistance is crucial for fabricating high-performance electronic and optoelectronic devices. As beta-gallium oxide (β-Ga 2 O 3 ) with a low-symmetry monoclinic structure exhibits anisotropic electronic properties, we investigated the anisotropic contact resistance of β-Ga 2 O 3 by fabricating trench contact structures on six distinct crystallographic planes ((001), (100), (101), (102), (201), and (−201)) using photo-enhanced metal-assisted chemical etching on undoped (010)-oriented substrates. Trench contact structures enable contacts on distinct crystallographic planes, overcoming the restriction of contact formation to the grown surface. Transfer length method analysis revealed that trench contacts on the (−201) plane yielded the lowest contact resistance (0.23 kΩ·mm). The low atomic density and surface energy en…