Bottom-up material technologies

• Liquid crystals: The research is related to displays, switchable interconnections and biosensors. We investigate liquid crystal based spatial light modulators, color filters, silicon waveguides and non-linear spatial solitions. The expertise is based on technology (clean-room facilities for photolithography and device assembly, including glass substrates and silicon wafers), experimental setups (electro-optical characterization, current measurements, polarization microscopy) and numerical simulations (LC director calculation, optical transmission, waveguiding).
• Colloidal nanocrystals: colloidal nanocrystals are a class of nanomaterials somewhere in between molecules and bulk solids. They have the typical solid crystal structure, but their properties can be tuned by changing their size and their shape. This make up the starting point of a multidisciplinary research activity, involving the development of novel synthesis recipes, the processing of nanocrystals into larger units, the characterization of chemical and physical properties and their application. At present, applications involve the development of novel photonic devices and the production of substrates for CNT catalysis.
• Contacting materials/thin films: Characterization and control of the texture of contacting materials. Development of in-situ characterization techniques to study microstructural evolution in thin films. Characterization of the growth stress in contacting materials. Study of the formation and properties of germanides and carbides as potential contacting materials to Ge and C containing semiconductors (SiGe, Ge, carbon nanotubes, SiC, diamond).
• Functional metal coatings: Study of atomic layer deposition as metallization technique for contacting and coating nano-structures.
• Thin film phosphors and the associated powder phosphors: growth and characterisation of photo- and electroluminescence of thin sulphide phosphors. Development of application-specific luminescent materials (phosphors for wavelength conversion in LEDs, persistent phosphors for safety applications, thin film embedded phosphor particles, self-assembled textured phosphor layers on template substrates).

Top-down material technologies

• mastering nano-scale complexity in materials: nanotechnology-based approaches target the production of nanostructured materials to make progress in the scaling-down of photonic devices. Main studied material systems are Silicon-on-Insulator (SOI) and III-V semiconuctors.
• Mastering of heterogeneous material integration: semiconductor-semiconductor integration; semiconductor-LC integration; semiconductor-metal integration; semiconductor-nanocrystal integration; semiconductor-chemic integration; semiconductor-magnetic material integration.
• Flexible materials for photonics: Different commercially available polymers with excellent optical, mechanical, and environmental properties are being investigated to integrate optical waveguides, light sources, detectors, and electronic circuitry with both rigid and flexible substrates.

Characterisation/screening/monitoring of materials

• Fiber sensors: development and application of fiber sensors
• Electrophorotic microscopy: development of electrophoretic characterization system
• Optical characterization: application of spectrophotometry, spectroscopic ellipsometry, photoluminescence spectroscopy, cathodoluminescence spectroscopy, confocal microscopy, FIB, AFM STM, BEEM TEM, SEM, XRD ...:

Silicon Photonics Platform

• The Silicon Photonics Platform provides access to wafer-scale CMOS fabrication facilities for research and prototyping of photonic integrated circuits of world-wide academic and industrial R&D groups.