Heterogeneous Integration of novel ultra-wide band gap oxides on silicon

• Applicant: Professor Dr. Roman Engel-Herbert
• Subject Area: Synthesis and Properties of Functional Materials ; Experimental Condensed Matter Physics ; Thermodynamics and Kinetics as well as Properties of Phases and Microstructure of Materials
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 551350199

The goal of the collaborative research project is to demonstrate that novel ultra-wide band gap semiconductor oxides – namely GeO2 and SrSnO3 – can be integrated with the conventional semiconductor technology platform silicon. Two different strategies for the heterogeneous integration of these structurally and chemically dissimilar oxide semiconductors will be employed and evaluated: (i) mechanical transfer of oxide nanomembranes with rutile structure; (ii) direct growth of a metamorphic buffer layer with perovskite structure on silicon. Doping strategies for rutile and perovskite oxide semiconductors will be established and device functionality of these ultra-wide band gap materials integrated on silicon will be demonstrated by fabricating and testing GeO2- and SrSnO3-based devices. Large industrial and societal impacts of the proposed research stems from the inherent properties of ultra-wide band gap semiconductors that are ideally suited to control the now emerging smart and delocalized power grid architectures and allow to effectively integrate environmentally friendly and carbon neutral power generation solutions, such as photovoltaic or wind turbines. Digital controllers and switches made from ultra-wide band gap semiconductors are required to realize high performance electric motors to drive the ecologic revolution in the automotive industry. Aside from the ability to extend semiconductor-based controllers, sensors and detectors to harsher environments when using larger band gap semiconductors – such as higher temperatures or higher radiation levels – additional application spaces open up, such as deep-UV optoelectronic device, specifically photodiode and photodetector for purification-disinfection of air, water, or surfaces, as well as solar-blind UV-C photodetectors for environmental monitoring, such as flame detection or non-line-of-sight communication solutions. The proposed joint research project addresses to overcome a fundamental barrier towards maturation and scale of this class of ultra-wide band gap semiconductors. It therefore has the potential to overcome existing materials maturation barriers, will provide new insights into the interface physics in artificial oxide heterostructure, and expand the versatility of rutile and perovskite oxide semiconductors, therefore contributing to the ongoing global scientific and technological efforts in the research field of ultra-wide band gap semiconductor materials.

• DFG Programme: Research Grants
• International Connection: South Korea
• Partner Organisation: National Research Foundation of Korea, NRF
• Cooperation Partner: Professor Junwoo Son, Ph.D.