PhD opportunity (starting 10/2021)

Fabien Massabuau

Photoconduction of wide bandgap semiconductor materials and devices

Wide bandgap semiconductors (bandgap > 3.5 eV) are vital materials for applications in ultraviolet (UV) optoelectronic devices for, e.g., biochemical sensing, water purification, or high-power transistors. Photoconduction is one of the fundamental properties of semiconductors whereby incident photons at the appropriate energy generate free carriers in the material, thus increasing its conductivity. Studying photoconduction can theoretically reveal important linkages between the electronic, optical and structural properties of the studied material that would help develop new strategies to improve the efficiency of wide bandgap semiconductor devices.

The student will investigate the photoconduction properties of several wide bandgap semiconductors, with a particular focus on corundum phase alpha Gallium Oxide (α-Ga2O3). To achieve this, the student will use the newly built (and only in the UK) setup for wide bandgap photoconduction measurements. The analysis will be complemented with photoluminescence (PL) and UV-vis transmittance spectroscopy measurements, to correlate with the material optical properties. Finally, cathodoluminescence (CL) and electron beam-induced current (EBIC) techniques in the scanning electron microscope (SEM) will be used to observe the identified mechanisms with a nanoscale resolution.

Throughout the project the student will also be exposed to other techniques such as atomic force microscopy (AFM), X-ray diffraction (XRD), electron channelling contrast imaging (ECCI), transmission electron microscopy (TEM), as well as theoretical modelling. We will work in close collaboration with the crystal growers in order to build an in-depth understanding of how the growth affect the photoconduction properties in order to produce materials for efficient devices for UV optoelectronics.

We are looking for a highly motivated, proactive individual with keen interest in experimental physics and knowledge in the following areas: semiconductor materials and devices, semiconductor physics, characterisation techniques, and crystalline defects. Prior experience with the aforementioned experimental techniques is preferable.

To apply, send a cover letter, CV and a recent transcript via email at f.massabuau@strath.ac.uk.

Qualifications:
BSc (Hons) 2:1 or equivalent degree in physics /materials science/engineering.

Funding:
There is no funding for this project (self-funded students only). Please contact f.massabuau@strath.ac.uk to discuss applications for scholarship.

Special Issue in Micromachines

Fabien Massabuau

Fabien is guest editor of the Special Issue in Micromachines on “Wide bandgap semiconductors based solar-blind photodetectors”.
He is sharing this duty with co-editors Robert Martin (University of Strathclyde), Paul Edwards (University of Strathclyde), Weihua Tang (Beijing University of Posts and Telecommunications), and Chong-Xin Shan (Zhengzhou University).

Find out more here. Deadline 15 July 2021.

IOP Twitter Poster Conference

Fabien Massabuau

Fabien and colleagues from Liverpool took part in the IOP Twitter Poster Conference (15-16 July 2020). Here are the contributions.

UKNC Winter 2020 – Cardiff

Fabien Massabuau

We were at the UKNC winter meeting in Glasgow (08-09 Jan). Fabien was giving an overview of our work on Ga2O3.

PhD opportunity (starting 10/2020)

Fabien Massabuau

Characterisation of Ga2O3 materials for ultraviolet optoelectronic devices

Wide bandgap semiconductors are the materials of choice for fabricating devices such as solar-blind detectors and ultraviolet (UV) light emitting diodes which are important enabling-technologies for water purification, biological and chemical sensing, flame detection, or communications. With a bandgap of 5 eV, gallium oxide (Ga2O3) is currently thought as one of the most promising materials for next generation UV optoelectronics and power electronics. In particular, the α phase of the compound (α-Ga2O3) offers unrivalled promises for tuning the operation wavelength of the device in the UV range – hence enabling the fabrication of devices for specific end-applications (e.g. to detect of a given pathogen in water). The α phase is however metastable, meaning that reliable synthesis of the material has for long been a challenge – which has been overcome recently. Consequently, little is known, at the experimental or theoretical level, about the mechanisms that lead to light emission/sensing in these materials. It is however vital to understand the inner mechanisms of the material in order to deliver efficient devices to nowadays challenges.

We are looking for a student to investigate the structural, chemical, and optical properties of α-Ga2O3 materials at the nanoscale. The project will build on the world-leading electron microscopy and spectroscopy capabilities of the Semiconductor Spectroscopy and Devices (SSD) group at the University of Strathclyde, which include electron probe micro-analysers (EPMAs) and low-vacuum scanning electron microscopes. The student will conduct characterisation using the following techniques: cathodoluminescence (CL), electron beam induced current (EBIC), electron channelling contrast imaging (ECCI), electron backscattered diffraction (EBSD), and energy/wavelength dispersive X-ray spectroscopy (EDX/WDX), as well as photoluminescence (PL). Throughout the project the student will also be exposed to other experimental techniques such as atomic force microscopy (AFM), X-ray diffraction (XRD), transmission electron microscopy (TEM), as well as theoretical modelling. We will work in close collaboration with the crystal growers (e.g. at the University of Liverpool) in order to build an in-depth understanding of how the growth affect the materials properties in order to deliver efficient devices for UV optoelectronics.

We are looking for a highly motivated, proactive individuals with keen interest in experimental physics and knowledge in the following areas: semiconductor materials and devices, semiconductor physics, characterisation techniques, and crystalline defect. Prior involvement to similar experimental activities is preferable.

The studentship is fully funded for 3.5 year.  UKRI eligibility requirements apply.

To apply, send a cover letter, CV and a recent transcript via email at f.massabuau@strath.ac.uk.