Abstract
This doctoral project investigates the design, fabrication and testing of Germanium implanted gratings in silicon on insulator waveguides. Integrated Bragg gratings are an interesting candidate for telecommunication applications, optical filtering, and for the fabrication of integrated photonic sensors, and this work demonstrates how it is possible to use well established microelectronics manufacturing technologies such as ion implantation to reinterpret the fabrication and applicability of these specific devices. In this work we demonstrate that a periodic change in the refractive index can be introduced on a silicon waveguide by ion implantation induced amorphization to produce integrated Bragg gratings compatible with CMOS processing techniques. Germanium implanted gratings can be also erased by an appropriate thermal treatment, opening the way to a range of new applications such as optical wafer scale testing. An extinction ratio up to 30dB has been demonstrated in transmission for the fabricated implanted Bragg gratings with lengths up to 2mm. Eras ability results are also presented, demonstrating how the grating effect can be selectively eliminated by either rapid thermal annealing or UV pulsed laser annealing. The possibility of employing erasable grating structures in optical wafer scale testing schemes is also discussed. This thesis contains no material which has been accepted for a degree or diploma by the University of Surrey or any other institution, except by way of background information and duly acknowledged in the thesis, and to the best of my knowledge and belief no material previously published or written by other authors except where due acknowledgement is made in the text of the thesis.