Polymer Brush-Assisted Fabrication of Layered Metal Oxide Heterostructures for Future Electronic Device Applications

For the future advancement of electronic devices, the sustainable use of materials and a reduction of the energy consumed are factors which need to be considered, as well as performance and size. This has motivated the need to explore alternative processes in integrated circuit manufacture. In this study, we present a novel and cost-effective polymer brush infiltration technique for fabricating layer-by-layer dielectric-semiconductor-dielectric nanofilms. A polymer brush template was employed to facilitate the uniform infiltration of aluminium oxide (Al2O3) and indium oxide (In2O3) precursors, and subsequent UV/ozone treatment to achieve the formation of oxide film layers. The structural integrity, composition, and surface morphology of the layers were characterized using atomic force microscopy (AFM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). Electrical measurements confirmed the insulating behaviour of the complete Al2O3/In2O3/Al2O3 gate stack, whereas capacitance-voltage (CV) characteristics revealed charge trapping behaviour associated with the In2O3-containing structure. This work demonstrates a scalable and straightforward fabrication strategy for Al2O3/In2O3/Al2O3 multilayer oxide heterostructures. Structural and MOS capacitor characterization establish the quality of the fabricated multilayer stack and its charge trapping behaviour, providing a promising materials platform for future oxide electronic devices.