Photonic waveguide engineering using pulsed lasers — A novel approach for non-clean room fabrication!

Over the last 25 years has seen an unprecedented increase in the growth of phonic components based on semiconductor and solid-state lasers, glass and polymer based optical fibres, and organic LEDs. Emerging technology for component engineering must embed dissimilar materials based devices into an integrated form which is more efficient. In this article, we demonstrate techniques for overcoming the materials related limitations by adopting thin-film deposition techniques based on nano- and femto-second pulsed laser deposition. Three examples of thin-film fabrication for near-IR devices using Er³⁺-ion doped glass-on-GaAs, Er³⁺-ion doped glass-polydimethyl silane (PDMS) polymer, and Tm³⁺-doped nano-silicon thin films and gain medium waveguides are discussed. The modelling tools are used a priori for waveguide engineering for ascertaining the extent to which the structural incompatibility due to mismatch strain can be minimized. The structure and spectroscopic properties of Er³⁺-ion doped thin films on silica, polymer, and semiconductor GaAs substrates were examined in detail and are reported. We demonstrate the formation of glass-polymer superlattice structures for waveguide fabrication for overcoming the solubility limits of Er³⁺-ions in PDMS polymers. For inscribing waveguides in superlattice structures and nano silicon structures, the ablation machining using fs-pulsed Ti-sapphire laser was used, and the resulting spectroscopic properties of waveguides are discussed.