Research Fellow

The Semiconductor Research Group in the Department of Physics at the University of Warwick is recruiting a Research Fellow with outstanding experimental skills in semiconductor materials science and cryogenic electrical characterisation.

The appointment supports a collaborative EPSRC–NSF project with the California Institute of Technology (Caltech), USA: "Towards Ultralow-Noise SiGe Heterojunction Bipolar Transistors for Quantum Technology and Beyond: Epitaxial Engineering of Cryogenic Charge Transport."

The research investigates how epitaxial layer design, alloy composition, strain, doping, interfaces and defects govern the electrical characteristics of SiGe heterojunctions and ultimately the cryogenic performance of SiGe heterojunction bipolar transistors (HBTs).

You will investigate Si/SiGe heterostructures grown using Warwick's in-house reduced-pressure chemical vapour deposition (RP-CVD) facilities.

A defining element of the role is independently performing and interpreting current–voltage (I–V), capacitance–voltage (C–V) and conductance–voltage (G–V) measurements over temperatures from room temperature down to approximately 2 K. This includes assessment of bias-, frequency- and temperature-dependent effects, experimental artefacts, and the physical mechanisms responsible for non-ideal junction behaviour.

You will integrate these results with rigorous structural and materials characterisation, particularly cross-sectional transmission electron microscopy (XTEM/TEM), high-resolution X-ray diffraction (HR-XRD), atomic force microscopy (AFM) and relevant complementary methods.

Your findings will inform the interpretation and optimisation of SiGe epitaxial heterostructures and provide the materials perspective for the international project team.

HBT device fabrication is undertaken by collaborators, not at Warwick. Where relevant, the role may include focused ion beam (FIB) specimen preparation and SEM/XTEM characterisation of collaborator-fabricated HBTs.

You will benefit from specialist semiconductor and low-temperature measurement facilities, scientific collaboration with Caltech and opportunities to publish and present internationally.

This is a laboratory-based experimental research position requiring full-time on-site working at the University of Warwick. Due to the hands-on nature of the experimental activities, remote or hybrid working arrangements are not available for this position.

About You:

We are seeking an accomplished, experimentally focused semiconductor materials scientist with a PhD, or near completion of a PhD, in semiconductor physics, materials science, materials engineering or a related discipline.

You will bring a convincing record of high-quality original experimental work, sound scientific judgement and clear personal contributions to research outputs.

An essential requirement is substantial, direct hands-on experience of all three semiconductor electrical techniques: current–voltage (I–V), capacitance–voltage (C–V) and conductance–voltage (G–V).

You must also demonstrate practical low-temperature electrical measurement experience from room temperature to approximately 2 K, including setting up or operating suitable instrumentation, acquiring reliable measurements, troubleshooting and interpreting the results. Experience limited to post-processing data collected by others is not sufficient.

We expect a robust understanding of semiconductor transport and junction physics, including doping, carrier freeze-out, leakage, contact effects, admittance and interface/defect responses.

You should be able to distinguish genuine physical phenomena from contact, parasitic, instrumentation and other measurement artefacts through quantitative analysis of temperature-, bias- and frequency-dependent data.

You will also have substantial hands-on semiconductor materials characterisation experience, with practical competence in at least two complementary techniques among XTEM and HR-XRD, and the ability to interpret and correlate evidence from these methods.

Knowledge of AFM, SEM, FIB, SIMS, EDX, XRR, FTIR, or Hall effect measurements will be an advantage; expertise in every technique is not required.

Relevant Si/Ge/SiGe epitaxy, heterojunctions or cryogenic electronics experience would be particularly welcome.

You will be organised, collaborative, committed to safe and reproducible research, and able to communicate experimental methods, uncertainties and findings clearly.

If you are near submission of your PhD, or have not yet had it conferred, any offers of employment will be made at Research Assistant level, at the highest spinal point of pay grade 5 (£35,302 per annum). Upon receipt of evidence confirming the successful award of your PhD, you will be promoted to Research Fellow, at the lowest spinal point of grade 6 (£36,320 per annum).

Benefits include an attractive pension scheme, a generous holiday allowance plus Christmas closure, excellent learning and development opportunities, and savings on a wide range of products and services. A generous maternity/paternity/adoption/parental leave policy and onsite childcare facilities are offered. The University is a Living Wage employer.