PhD student (f/m/d) – High-Performance Float Zone Crystalline Silicon for Application in Einstein Telescope Leibniz Institute for Crystal Growth in Germany

The Leibniz Institute for Crystal Growth (IKZ) in Berlin is offering a PhD student position (f/m/d) on High-Performance Float Zone Crystalline Silicon for Application in Einstein Telescope. This is a research-focused doctoral opportunity in a leading materials science and crystal-growth institute that works across basic research, applied research, and pre-industrial development in cooperation with universities, academies, and industry.

The project is linked to the future Einstein Telescope, a next-generation gravitational-wave observatory under development in Europe. Because crystalline silicon offers excellent mechanical and thermal properties, it is a leading candidate material for key interferometer components. However, current crystal-growth methods do not fully satisfy the demanding requirements for size, geometry, optical quality, and thermal/mechanical performance. The project therefore focuses on the Float Zone (FZ) growth method, which is known for producing silicon with exceptionally high purity and structural perfection.

As a PhD researcher, you will take part in comprehensive experimental work involving FZ silicon crystal growth, advanced material characterization, data analysis, and the study of impurity-related mechanisms that influence the optical and mechanical properties of crystalline silicon. The long-term goal is to develop ultra-pure silicon substrates and fibres that can meet the performance needs of cryogenic gravitational-wave detectors.

The host group, FZ-Si, has internationally recognised expertise in high-purity silicon crystal growth and benefits from a strong research environment combining crystal-growth development, numerical modelling, equipment engineering, and systematic characterization. The group also participates in the international Einstein Telescope collaboration and contributes to ET-related materials research within the Research Unit Berlin.

Eligibility highlights include an MSc degree in physics, chemistry, applied sciences, materials science, or a related discipline; hands-on FZ silicon crystal-growth experience; strong knowledge of semiconductor materials; familiarity with characterization tools such as 4PP, MDP, µ-PCS, LPS, and PL; and good English communication skills. Basic German is an advantage. Experience with Czochralski growth, directional solidification, optical/mechanical characterization, or analytical techniques such as FTIR, ICP-OES, GDMS, and SIMS is beneficial but not required.

The appointment is fixed-term for three years and is paid according to TVöD Bund E13 (75%), with standard public-sector social benefits including 30 vacation days in a 5-day week and flexible working hours. IKZ emphasizes support for early-career scientists, work-life balance, equal opportunities, and diversity, and encourages applications from women and candidates with disabilities.

Interested applicants should submit a letter of motivation, curriculum vitae, and all relevant certificates. Applications are submitted online via the IKZ job advertisement. The position is open immediately and applications will be accepted until it is filled.