Seminar: Jan Eric Stehr “Magnetic Resonance Spectroscopy and Wide Bandgap Semiconductors”

Thursday January 31 at 15:15, Associate Professor Jan Eric Stehr from Linköping University will give a talk in k-space at Solid State Physics department.

The title and abstract of the talk are below.

Magnetic Resonance Spectroscopy and Wide Bandgap Semiconductors.

Abstract:

β-Ga2O3 is a wide bandgap semiconductor that is attractive for various applications ranging from transparent conducting electrodes to UV optoelectronic devices, and to power electronics. 

The key to the realization of device applications is to achieve control over conductivity by doping and mitigation of trap states, as most of the electronic properties of β-Ga2O3 are affected by the presence of dopants/contaminants and/or intrinsic defects. 

Here, transition metals are of special importance, since they are unintentionally present during the growth, used as intentional dopants or used for ohmic contacts. 

Therefore, it is of crucial importance to understand the electronic structure of those impurities.

In this seminar I will first give a brief introduction to magnetic resonance spectroscopy, which is a powerful tool to provide information on the chemical identity, local structure, charge state, energy level and quantification of defects and impurities in semiconductors. 

Next, I will talk about the electrical and optical properties of transition metals like Co, Cu and Cr in β-Ga2O3, which are often unintentionally present during the growth or used as intentional dopants, investigated by magnetic resonance spectroscopy and magneto-optical characterization techniques.