Metal Organic Chemical Vapor Deposition of nickel oxide thin films for wide band gap device technology

• NiO thin films are potential candidates for power microelectronics applications.
• NiO epitaxial thin films have been grown on AlGaN/GaN substrates by MOCVD.
• Comprehensive insights of the MOCVD process have been performed.
• NiO thin films showed to be a good dielectric for MOSFET in GaN.
• NiO thin films demonstrated to possess good dielectric constant (11.7).

Epitaxial nickel oxide (NiO) thin films have been grown by Metal Organic Chemical Vapor Deposition on AlGaN/GaN heterostructures. Critical growth parameters have been studied in order to optimize the deposition process of NiO films suitable for applications in GaN-based devices. In particular, a second generation precursor has been used as nickel source, namely the N,N,N′,N′-tetramethylethylenediamine adduct of nickel bis 2-thenoyl-trifluoroacetonate, using different deposition temperatures and oxygen flow values. Optimized operative conditions allowed the growth of epitaxial thin films which exhibited a permittivity of 11.7, close to the bulk value. The electrical characterization of the obtained epitaxial films pointed out to promising dielectric properties for AlGaN/GaN transistor technology.