ATTENTION !!! SEMINAIRE ANNULE !!! Gallia(Ga2O3) : Surprising electronic properties

Orateur : Ekaterine CHIKOIDZE (GEMaC, Université Paris-Saclay, UVSQ-CNRS, France)

Recent breakthroughs in material quality have led to a “rediscovery” of Ga2O3 such as a high band gap ( 5eV) transparent conductor, transparent field-effect transistors, photodetector but also as a platform for power electronic devices. From a power devices perspective, Ga2O3 transistors and diodes have the potential to deliver excellent characteristics in the form of high breakdown voltage, high power and low losses because of these superior material properties. Ga2O3 is also particularly suitable within solar blind photodetectors and deep ultra-violet light emitting diodes. Physical properties of nominally undoped b-Ga2O3 thin-films grown on c, r-sapphire and Si substrates by pulsed laser deposition (PLD) and MOCVD will be discussed. An unexpectedly low 2D-like resistivity has been shown for n type Ga2O3/r-Al2O3 which is resistant to high dose proton irradiation and largely invariant (metallic) over temperatures from 2 to 850K. 1 we have showed the use of Ga2O3 electrodes has enabled, for the first time, an above-bandgap bulk photovoltaic effect on sandwich-like capacitors with transparent conducting electrodes (the architecture of solar cells) and under white light.2 We have demonstrated that Ga2O3 is also the intrinsic (or native) p-type TSO 3 with the largest bandgap for any reported p-type TSO (e.g. NiO, SnO, delafossites, oxychalcogenides). The achievement (post annealing) of hole mobility in excess of 10 cm2/Vs and (high temperature) free hole concentrations in the 1017 cm-3 range.4 Surprising optoelectronic properties of Gallia opens a new pathway for its integration in Renewable energy technologies and green transport as electrical vehicles, high speed trains.

Télécharger dans mon agenda