The correlations between the properties of an AlGaN/GaN device and the Schottky contact structure with and without nanoparticles (NPs) have been investigated. It has been found that the use of NPs effectively lowers the barrier height of the electrical contacts to AlGaN/GaN 2-DEG heterostructures. The Schottky barrier height of the Ni contact with embedded Au-NPs was significantly reduced by ∼0.16 eV compared to the reference sample without NPs. The fabricated AlGaN/GaN SBDs with embedded Au-NPs show a turn-on voltage of ∼1.7 V and an on-resistance of ∼12.5 Ω·mm, respectively.