Gallium Oxide-based RF power devices with thermal management

About the Project

Gallium Oxide-based RF power devices with thermal management

Research Project

High power radio frequency (RF) semiconductor technologies are of critical importance to a wide range of applications including defence, aerospace, science, medicine, and industrial heating. They enable systems to communicate across greater distances, process signals faster and more efficiently, and operate under extreme conditions. Gallium Oxide (Ga2O3) is a semiconductor material with strong promise for producing the next generation of efficient, high power RF devices due to its high saturation velocity.

One of the core challenges is management of self-heating, a critical bottleneck due to the low thermal conductivity of Ga2O3. With efficiency of RF amplifiers being inherently lower than that of e.g. power devices (the most commonly explored use of Ga2O3) thermal dissipation is a key factor in determining the maximum achievable areal RF output power density and reliability. In this project, you will achieve efficient thermal management of Ga2O3 RF power devices through methods including integration of microfluidics positioned close to active device area and integration with diamond heat spreaders. The development of efficient, high power RF devices based on Ga2O3 will unlock routes to integration with power devices on a single material platform, with strongly positive implications for system size and manufacturing cost.

The position will be split between the University of Bristol, UK and Imec, Belgium. The CDTR group at the University of Bristol has Ga2O3 growth capability that will be utilized here, in addition to a strong track record of material characterization (including electronic traps, management of which is critical to RF device performance) and thermal management of RF devices, all of which will be undertaken in this project. Imec has strong expertise in RF device fabrication and characterization that will be utilized to produce and test the devices.

A world-class environment for your research degree

The School of Physics is offering a portfolio of PhD Scholarships across all its world-class research groups. These prestigious Scholarships represent a great opportunity to start your Postgraduate Research Career working with world-class academics in a supportive training and development environment. Physics at Bristol was ranked 5th for Research in the 2022 Research Excellence Framework (REF) results, and the University of Bristol is truly world-leading: 55th in the QS World University Ranking (2024) and 81st in the Times Higher Ranking (2024).

What does a Scholarship cover?

For home students, the scholarships will cover living expenses (UKRI rate), University tuition fees, and training and support expenses. We also welcome applications from outstanding international candidates.

The Bristol Physics Graduate Research Community

If successful, you will become a member of the Physics Graduate School, a vibrant and diverse community of 200-plus research students from a wide range of countries and backgrounds. The Graduate School:

• runs a comprehensive induction programme to get you off to the best possible start in your research, and a rolling programme of targeted skills training on writing, presenting, project-planning, etc.
• operates a “one-stop shop” approach to help you navigate through the University procedures
• organises meetings for postgraduate opportunities, and support in transitioning to post-PhD careers
• connects you to the wider University, including the Bristol Doctoral College.

How do I apply?

You will need (1) a CV, (2) a Personal Statement, which is a one- to two-page document introducing yourself and outlining your motivation for PhD research, and (3) a transcript of any qualifying degrees (completed and/or underway).

You do not need a research proposal, but must specify Professor Martin Kuball as the academic supervisor for the project.

Applicants will be assessed on merit, and interviews will be held for shortlisted applicants.

You need to apply through the University of Bristol application system. Please select Physics PhD on the Programme Choice page. The School of Physics supports Diversity and Equality, and we invite all eligible candidates to apply. We encourage applications from under-represented groups. We hold a Bronze Athena Swan award and a Physics Juno Champion award.

Please specify “IMEC Scholarship” on the application form as your source of potential funding. Early application is encouraged.

What are the candidate requirements?

A first degree in physics or a related subject, normally at a level equivalent to at least UK upper second-class honours, or a relevant postgraduate master's qualification.

English language requirements

If English is not your first language, you need to meet English Language Profile F.

Contacts and further information

Please contact the Bristol Physics Graduate School at: physics-pg@bristol.ac.uk