This award to the University of Toledo is for the acquisition of a Terahertz Spectroscopic Ellipsometer to measure optical properties and structure of materials over a range from 0.11 to 1.45 THz. Optical properties in this region are expected to be sensitive to vibrational modes and absorption due to free carriers; and spectroscopic ellipsometry can also be used to deduce layer thicknesses, interfacial formation, and gradients. In the THz regime, optical properties approach the DC limit, thus they can be used to extrapolate electrical properties of materials (carrier concentration, mobility, etc.). The ability to extract electrical properties from a non-contacting optical measurement is particularly attractive for probing materials in device structures or where traditional electrical characterization is difficult including photovoltaic materials and devices; microbolometer materials for uncooled infrared sensors; structured materials including nanoparticle films, carbon nanotube films, metamaterials, and engineered thin films; ferroelectrics and other oxide materials; thin film transistors; and, polymer thin films.
The THz Spectroscopic Ellipsometer at the University of Toledo will assist in graduate and undergraduate student research, as well as enabling collaborations between researchers at other universities, government laboratories, and industry, in uncovering connections between optical, electrical, and structural properties of materials. It is believed to be the only tool of its kind available on both a user fee and collaborative basis and is expected to provide new opportunities and further develop networks of measurement and analytical expertise. Research resulting from THz spectroscopic ellipsometry has strong potential to uncover new fundamental information and will enhance the knowledge base of physical mechanisms in materials and devices for technological (component layers in electronic circuits), security (chemical and infrared sensors), and energy (photovoltaics) applications. Simultaneously, it will enable the research training of the next generation of scientists and engineers, who will further develop its capabilities and apply them in exploring new research areas.
