PhD student position; f​/m​/d) K 18

The Leibniz-Institut für Kristallzüchtung (IKZ) is a leading research institution in the field of science & technology as well as service & transfer of crystalline materials. Our goal is to enable solutions for pressing societal challenges (e.g. communication, artificial intelligence, climate protection, health, etc.) through modern electronic & photonic technologies. The work covers the entire spectrum from basic and applied research to pre-industrial development and is carried out in cooperation with national and international partners from universities, academies and industry.

The institute is part of the Forschungsverbund Berlin and a member of the Leibniz Association. You can find more details on the institute webpage:

The Leibniz-Institut für Kristallzüchtung is currently looking for a PhD Student (m/f/d) for the topic:

Silicon (Si) single crystals are indispensable in microelectronics and power electronics. They are also a leading candidate material for the test mass mirrors of the proposed Einstein Telescope (ET), a next‑generation underground gravitational‑wave observatory. As a partner in the ET collaboration, our research focuses on the growth of ultra‑high‑purity, high‑quality bulk Si single crystals using advanced melt‑growth techniques. The goal is to develop Si mirror substrates with exceptional optical properties that enable the higher sensitivity required for the ET interferometer.

In this BMFTR‑funded research project, we aim to establish a novel magnetic field assisted Czochralski (MCz) crystal growth process to produce ultra‑pure, high‑quality Si single crystals with extremely low optical absorption.

As a doctoral research student, you will contribute to the development and optimisation of this innovative crystal growth process. Your research will involve detailed investigations of melt growth dynamics, reduction of contamination originating at the crucible–melt interface, and approaches to further improving crystal purity. You will study the influence of melt convection on impurity transport from the crucible to the growing crystal and develop advanced methodologies to achieve the stringent material quality required for the application.

In the host research section at IKZ, dedicated crystal growth equipment is available, and you will work alongside the most experienced semiconductor researchers, where your independent thinking is strongly supported and novel ideas are particularly encouraged. In‑house expertise in crystal growth, sample preparation and characterization combined with a state‑of‑the‑art laboratory infrastructure provides outstanding opportunities to reach the research goal. Are you excited to help develop the silicon crystals that will enable future discoveries in fundamental physics?

• Czochralski growth of Si crystals with and without magnetic field
• A systematic study of the growth process to obtain high‑purity crystals
• Wide‑range of analyses of the crystals using in‑house characterization tools as well as in collaboration with partners (e.g. DZA)
• Estimating oxygen, carbon and other trace impurity concentrations using FTIR and other advanced spectroscopy measurement techniques
• Point‑defect analyses in the crystals and provide feedback for their control
• Correlating the quality of the MCz‑Si with the FZ Si crystals

• Master degree in physics, chemistry, material science or other related disciplines
• Strong background in semiconductor physics and materials processing
• Knowledge on basic characterisation of materials
• Motivation and passion for scientific research
• Ability to work independently in a…