Shweta Singh

Doctoral candidate

Deutsches Elektronen-Synchrotron DESY
Notkestrasse 85
22607 Hamburg



Doctoral project

In-operando investigations of structure and function of nanowire optoelectronics

The project will employ X-ray coherent scattering methods (Bragg coherent X-ray diffractive imaging and ptychography) with X-ray nano-beams to reveal structural changes in nanowires implemented in devices in combination with electron microscopy as well as, electrical and optical device measurements.

The piezoelectric effect will be studied in annealed HfO2 films formed on III-V semiconductor substrates and nanowires using Bragg coherent X-ray diffraction technique. The samples will be measured in coherent X-ray beam at the same time as they are electrically driven. A dual goal will be pursued: (a) to thoroughly establish the piezoelectric coefficients in HfO2 films on III-V surfaces and nanowires as well as the spatial dependence, (b) to determine the resulting strain in the III-V substrates and nanostructure.