Mr Ayman Karar
Photonic and Nanotechnology project
I joined the Electron Science Research Institute as a PhD student in July 2009 and I have been involved in nanophotonic R&D activities. My work is focused on modelling, design, fabrication and testing of plasmonics-based high-responsivity Metal-Semiconductor-Metal (MSM) photodetectors.
Metal-semiconductor-metal (MSM) photo-detectors offer an attractive benefit over alternative photo-detectors such as conventional p-i-n photodiodes. An MSM photo-detector consists of interdigitated Schottky metal contacts on top of an active (absorption) layer. An MSM photo-detector is inherently planar and requires only a single photolithography step which is compatible with existing field effect transistor (FET) technology.
MSM photodetectors are very high speed devices due to their low capacitance, and they typically have very low dark currents. However, their responsivity is quite low compared to p-i-n photodiodes, because of the reflection from the metal and semiconductor surfaces.
I am currently investigating novel approaches to improve the responsivity of MSM photodiodes, by designing various nano-gratings (surface plasmon polariton SPP) on top of the MSM fingers to minimize surface reflections and guide the light to the sub-aperture and therefore trap a greater percentage of the incident light into the semiconductor layer.
I received a BSc (Honours) in physics from university of Khartoum, Sudan 2002 and Master of Material Physics and Nanotechnology from Linkoping University, Sweden 2006. For my masters research I worked on new III-V semiconductors (GaNand AlGaN) l for developing high-mobility transistors.
Mr Ayman Karar
Joondalup Campus: Building 8, Room 8.118
Telephone: (61 8) 6304 5146