Plasma Enhanced Atomic Layer Deposition Passivated HfO2/AlN/In0.53Ga0.47As MOSCAPs With Sub-Nanometer Equivalent Oxide Thickness and Low Interface Trap Density

The impact of in situ plasma-enhanced atomic layer deposition passivation on the electrical properties of HfO₂/In_0.53Ga_0.47As metal-oxide-semiconductor capacitors (MOSCAPs) has been studied. Excellent interface quality of high-k/III-V is achieved by aluminum nitride (AlN) interfacial passivation layer, including strong inversion behaviors and unpinned Fermi level. The band alignment of HfO₂/AlN/In_0.53Ga_0.47As structure with the valence band offsets of 2.81 ± 0.1 eV and the conduction band offsets of 1.9 ± 0.1 eV was obtained. Better interface and optimized high-k dielectric qualities are achieved using post remote-plasma treatment with either N₂/H₂ or NH₃ gases. Sub-nanometer equivalent oxide thickness HfO₂/AlN/In_0.53Ga_0.47As MOSCAPs with low interface trap density and low leakage current density have been characterized.