Regensburg 2010 – wissenschaftliches Programm
HL 3.5: Vortrag
Montag, 22. März 2010, 11:15–11:30, H14
Strain measurements on semiconductors: Raman experi-ments and simulation — •Andreas Talkenberger1, Gert Irmer1, Martin Abendroth2, Christian Röder1, and Cameliu Himcinschi1 — 1TU Bergakademie Freiberg, Institute for Theoretical Physics, Leipziger Str. 23, 09596 Freiberg, Germany — 2TU Bergakademie Freiberg, Institute for Mechnics and Fluid Dynamics, Lampadiusstr. 4, 09596 Freiberg, Germany
The characterisation of strains in semiconductors is crucial for microelectronic and photovoltaic applications. However, even for some widely used semiconductors the elastic properties are not well understood. For example, due to the lack of high-quality GaN bulk material it was not yet possible to determine the elastic constants with good precision.
Using Raman scattering we present a method which allows the determination of phonon deformation potentials in semiconductors derived from phonon frequency shifts under biaxial stress. The stress was applied by three-point bending and calculated by means of beam theory. In order to establish the technique we first investigated well studied semiconductor materials, e.g. silicon and gallium arsenide. The phonon deformation potentials found are in good agreement with earlier published values. Additionally, the strain fields were calculated by finite element methods.
The authors would like to thank the European Union (EFRE) as well as the Free State of Saxony for financial support.