When studying quantum dots one of the most important properties is the size of the band gap, and thus also their physical dimensions. We investigated these properties for silicon quantum dots created by means of plasma-enhanced chemical vapour deposition and annealing. To determine the band gap size we measured photoluminescence for ten dierent samples and to determine the physical dimensions we used an atomic force microscope. The photoluminescence measurements indicated that the intensity of the emitted photons varied across the samples, but did not indicate any shift in peak wavelength between samples nor any time-dependence of the luminescence. The peak wavelength was in the order of 600 to 620 nm, corresponding to a band gap of 2.0 to 2.1 eV and a physical size of approximately 3 nm. The AFM scans revealed densely packed quantum dots, where few single objects could be distinguished. In order to be able to perform a better statistical analysis, eorts would have to be taken to separate the quantum dots.
| Identifer | oai:union.ndltd.org:UPSALLA1/oai:DiVA.org:kth-103001 |
| Date | January 2012 |
| Creators | Lama, Lars, Nordström, Axel |
| Publisher | KTH, Fysik |
| Source Sets | DiVA Archive at Upsalla University |
| Language | English |
| Detected Language | English |
| Type | Student thesis, info:eu-repo/semantics/bachelorThesis, text |
| Format | application/pdf |
| Rights | info:eu-repo/semantics/openAccess |
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