Development of silicon nanostructures as light emitter and sensitizer for erbium emission
Silalahi, Samson Tua Halomoan
Date of Issue2009
School of Electrical and Electronic Engineering
Photonics Research Centre
Agency for Science, Technology and Research (A*STAR), Institute of Microelectronics (IME)
One of the motivation of Silicon (Si) photonics was to realize optical interconnect to alleviate the bottleneck encountered in the electrical interconnect, especially in high speed application. The key advantages of Si photonics are its excellent optical properties as well as its high yield and low production cost established in microelectronics industry. Accordingly, Si-based material has been intensively developed for different photonics components, such as light guiding, modulation and light detection. However one underlying fact is that Si-based material has not been successfully developed as a light emitter component, which is an integral part of optical integrated circuits. This is due to the indirect band gap property of Si material. Nanostructured Si, however, exhibits potential luminescence in visible to NIR wavelength and therefore attracted interest for realizing the light emitting component. Some of the advantages of Si-nanostructures based emitting structure are the broadband excitation wavelength (near UV to visible, 300-500 nm), the controllability of emission wavelength by tailoring the average size of Si nanostructures, as well as the sensitizing effect of Si-nanostructures on Erbium (Er)-related emission. However, there are still several challenges as follows. Firstly, a prolonged annealing in the range of 1100oC is normally implemented to form efficiently emitting Si-nanocrystals. Secondly, in general, controlling the Si-nanocrystal size by varying Si concentration is difficult to achieve. Thirdly, there is a need to optimize the energy transfer from Si-nanostructure and Erbium (Er) ions to increase emission intensity of Si-nanostructures sensitized Er system. Lastly, in the case of light emitting device, a more efficient light extraction is necessary. In this work, these challenges were addressed.
DRNTU::Engineering::Electrical and electronic engineering::Optics, optoelectronics, photonics