PhD student (f/m/d)

Tätigkeitsprofil:

“High-Performance Float Zone Crystalline Silicon for Application in Einstein Telescope”

The Einstein Telescope (ET) is a future gravitational-wave observatory currently under development in Europe. With its unprecedented sensitivity, it will explore the Universe with significantly greater depth and precision than current detectors, opening a new era of gravitational-wave astronomy. Due to its outstanding mechanical and thermal properties, crystalline silicon is considered the leading candidate material for the core components of the ET interferometer. However, existing silicon crystal-growth technologies cannot simultaneously meet all stringent requirements regarding crystal size, geometry, optical quality, and thermal and mechanical performance. Among available growth techniques, the Float Zone (FZ) method provides silicon crystals with the highest purity and structural perfection and is therefore the primary technology of interest for ET material baseline research. Our recently funded BMFTR project aims to investigate process-related properties of FZ silicon relevant to future ET operation.

As a PhD student, you will be involved in comprehensive experimental research including FZ silicon crystal growth, advanced material characterization, data analysis, and the identification of impurity-related mechanisms affecting the optical and mechanical properties of crystalline silicon. The ultimate goal of this research is to develop ultra-pure silicon substrates and fibres with properties enabling the performance requirements of cryogenic gravitational-wave detectors.

The host research group “FZ-Si” at IKZ has internationally recognised expertise in high-purity silicon crystal growth for advanced scientific and technological applications. The group provides a unique research environment through the close integration of crystal-growth process development with numerical modelling, growth-equipment engineering, and systematic material characterization. As a member of the international Einstein Telescope collaboration, the group contributes to ET-related materials research and development within the Research Unit Berlin. This position offers a unique opportunity for scientific exchange and collaborative experiments with leading European research groups, providing an excellent environment for successful project implementation and early-career scientific development.

Anforderungsprofil:

• MSc degree in physics, chemistry, applied sciences, materials science, or a related discipline
• Hands-on experience in FZ silicon crystal growth
• Solid knowledge of semiconductor materials
• Good knowledge of basic characterization techniques for semiconductor materials (e.g. 4PP, MDP, µ-PCS, LPS, PL)
• Basic knowledge of core optics and suspension requirements for cryogenic gravitational-wave detectors
• Motivation and passion for scientific research
• Ability to work independently and to collaborate effectively within a team of scientists, technicians, and students
• Very good written and spoken English; basic knowledge of German is an advantage

Prior experience in the following areas is considered an asset (but is not essential):

• Hands-on experience in Czochralski or directional solidification silicon crystal growth
• Knowledge of optical and mechanical characterization techniques
• Knowledge of analytical material characterization techniques (e.g. FTIR, ICP-OES, GDMS, SIMS)