The Leibniz Institute for Crystal Growth (IKZ) performs basic and applied research in the fields of
growth, characterization and processing of crystalline matter. It is part of Forschungsverbund
Berlin e. V. and a member of the Leibniz Association. The IKZ is a leading research institution in
the area of crystal growth of technologically important materials for micro-, opto- and power
electronics, sensors, optics and laser technology. This ranges from explorative fundamental
research to pre-industrial development.
IKZ invites applicants for a
available from December 1, 2017
, on the topic:
„Generation and evolution of structural defects during AlN bulk crystal growth, substrate
preparation, and AlGaN/AlN epitaxy“
As the white LED became a popular light source, research currently focuses on the preparation
of UV LEDs for disinfection applications. Such devices are made of AlGaN and AlN epitaxial
layers, which can be deposited on aluminium nitride (AlN) single crystal substrates. In order to
prepare epitaxial layers of highest structural perfection, the density of structural defects
(dislocations) on the substrate surface should be as low as possible.
At the IKZ AlN single crystals are prepared from the gas phase (PVT method) and subsequently
cut and polished into substrates; the neighbouring research institute FBH provides epitaxy on
Besides the participation in the growth of AlN bulk crystals, the task consists in exploring the
structural properties of the crystals, substrates, and epitaxial layers. The defect structure is
investigated by defect-selective wet chemical etching as well as by optical, X-ray, and electron
microscopy analysis. The work is targeted on determination and characterization of the origins of
defect formation, assessment of defect evolution along the process chain, and providing
conception and evaluation of novel approaches in order to reduce the defect density during AlN
crystal growth, substrate preparation, and epitaxy.
Applicants must hold a Diploma or an MSc degree in physics, materials science, chemistry or a
related discipline. Furthermore, we expect good English language skills, scientific selfdependence,
cooperativeness, and ability to work in a team.
For technical information please contact Dr. Jürgen Wollweber, Tel.: +49 30 6392 2843, e-mail:
The employment is limited and payment is according to TVöD (Treaty for
German public service). Among equally qualified applicants, preference
will be given to disabled candidates. The IKZ is an equivalent opportunity
employer and actively supports reconciliation of work and family life.
We await your informative application with reference to the job number
, including the usual documents, by October 15, 2017
. Please send
them to Mrs. Ruthenberg: email@example.com