Project R-3652

BOF NI project: Designing metal oxides semiconductors towards a lower bandgap and a higher mobility (Research)

There exists a broad range of oxide semiconductors (In-Ga-Zn-Sn-O) whose current use is restricted to amorphous thin films. Nevertheless, these materials already display carrier mobilities between 10 and 100 cm2/Vs, much larger than amorphous silicon and are therefore extremely interesting in view of optimized electronics. The ultimate aim is to increase the carrier mobility in oxides even more, to orders of magnitude beyond what has been achieved so far, and to open a new class of compounds for semiconductorapplications. The current project will contribute to this search and investigate pathways to control the bandgap and mobility of conducting oxides. These issues will be addressed by band gap engineering through the use of sub-oxides as well as artificial heterostructures and the investigation of epitaxial crystalline oxides. Hence, the goal of the project is to develop insights into the fundamental mechanisms underlying oxidesemiconductor properties aiming at oxides with a lower bandgap and higher mobility. The challenges that will be focused on are the deposition of (single) crystalline films as well as tuning the band gap by sub-oxide formation and synthesis of layered heterostructures. To this end, MBE and chemical solution deposition (sol-gel methods and hydrothermal epitaxy) will be employed in combination with specialised annealing methods.

01 January 2012 - 31 December 2015