Position-Dependent Properties of Novel Electronic Materials: Tunneling, Infrared, and Electromechanical Measurements

University Of Kentucky Research Foundation, Lexington KY

Investigators

Abstract

Technical: The two principal investigators of this award have developed probes to measure the infrared reflectance, tunneling spectra, and mechanical properties of small crystalline and thin film samples as functions of position. These probes, an infrared microscope with tunable diode lasers as light source, scanning tunneling microsocsope with long-distance scanner, and a helical resonator motion detector, will be used to study changes in electronic, molecular, and piezoelectric properties as functions of voltage, frequency, and distance from electrical contacts. The materials to be studied include organic semiconductors based on pentacene derivatives, being developed for applications in field-effect-transistors, and charge-density-wave materials, being studied as nano-torsional actuators, with the goals of improving our understanding of their conducting and piezoelectric mechanisms. Graduate students will gain experience in a wide range of characterizational and synthetic techniques. Undergraduate education majors (pre-service teachers) will work in summers not only to improve their appreciation of scientific techniques but to develop teaching tools for their future careers. Non-Technical: In recent decades, there has been an explosion of interest in using new electronic materials to replace conventional semiconductors in devices ranging from flexible displays to electromechanical actuators. The application of many of these materials faces not only large technical hurdles but questions in our understanding of their basic conducting and mechanical properties, including the effects of charge on the constituent molecules located near electrical contacts. The two principal investigators of this award have developed new optical, tunneling, and electromechanical probes that will be used to study the electronic, molecular, and mechanical properties as functions of distance from contacts. Materials to be studied are new organic semiconductors, to be utilized in transistors, and non-uniform charge distribution materials, with possible applications as mechanical actuators. Graduate students working on the project will gain broad experience in different characterizational and synthetic techniques that will prepare them for careers in industry, academia, and research laboratories. In addition, pre-service teachers will assist in the labs in summers to gain appreciation of scientific laboratory work and also prepare future teaching materials.