Application of Nitride based Semiconductors to High-speed Optoelectronics

International audienceIII-nitrides materials are very promising ternary alloy system that receives a lot of attentions thanks to theirs tunable bandgap that varies from near infrared to near ultraviolet regions. Until now, InGaN/GaN materials have been widely used in various applications like high efficiency solar cells, high-brightness blue to green LED as well as non-phosphor based direct white light generation. Their unique set of properties (optical index, electrooptic & piezoelectric effects) makes them suitable candidates for a number of potential optoelectronic applications as well for modulation, high speed switching, optical interconnection required for future full optical fiber links. In order to design efficient GaN-based active devices, it is a prerequisite to fully characterize the optical properties of III-nitrides materials. In this research, we report the optical indices and the losses of InxGa1-xN films grown by MOCVD. We report experimental results on a field effect refractive index change into gallium nitride structures using surface Plasmon. In order to understand the origin of the index modulation, we conducted a TEM analysis and discussed the influence of threading dislocations density. We discuss the design and the fabrication process of InGaN-based ultrafast devices