Defence of Micro and Nanosciences M.Sc. (Tech.) Joona-Pekko Kakko
The title of thesis is "Fabrication of Semiconductor Nanowires for Optical Studies”
Nanowires are wire-like structures with dimensions in the nanoscale. They hold promise as the platforms for next generation electronics and optics, such as light emitting diodes (LEDs) and solar cells. Especially the behaviour of light is affected by the small dimensions of the nanowires.
The optical properties of semiconductor nanowires were studied by fabricating nanowires and their ensembles with varied dimensions and spacings.
It was noted how the light trapping properties of the nanowires were enhanced with a dualtype nanowire structure and with a separate Parylene-C coating. Furthermore, fundamental optical wavemodes were identified directly from the nanowires using optical cross-polarization microscopy.
The nanowires were also studied using optical measurements when the spacing was varied, how they perform as sources of THz radiation, in the generation of second harmonic light and how quantized phonon vibrations change in the nanowires.
The results of the work can be used in the design of next generation LEDs and solar cell. Also, the development of new nanowire devices, such as nanowire lasers, could benefit from the results of the work.
Opponent: Professor Val Zwiller, KTH, Sweden
Supervisor: Professor Harri Lipsanen, Aalto University School of Electrical Engineering, Department of Electronics and Nanoengineering.
Contact information: Joona-Pekko Kakko, +35850 4312240, firstname.lastname@example.org