Research -
Novel Characterization Methods
Three Omega for Soft Films: The three omega method has proven to provide accurate and reliable measurements of thermal conductivity of thin films and other materials. However, if the films are soft and conductive, conventional methodologies to prepare samples for the measurement technique are challenging and often unachievable. Various novel modifications to the approach have been taken in the nanoEngineering laboratory to demonstrate that the differential three omega method may be employed to measure the thermal conductivities of soft conducting films of polyaniline. These include utilizing a shadow mask for metal deposition and developing a recipe for low temperature deposition of an insulating layer on a conductive soft film with a relatively low glass transition temperature. Our results demonstrate that a polyaniline film exhibits an increase in thermal conductivity with temperature, which is largely due to increasing heat capacity.
Nanoscale Mechanical, Electrical and Thermal Characterization Device: A characterization device was developed in the nanoEngineering laboratory in collaboration with Dr. Vikas Prakash from Case for nanomechanical testing on one-dimensional micro/nanostructures. The tool consists of a nanomanipulator, a three-plate capacitive transducer and associated probes, and is operated inside a scanning electron microscope. The transducer independently measures force and displacement with micronewton and nanometer resolution. Tensile testing of a polyaniline microfiber (diameter ~1µm) demonstrated the capabilities of the system. Efforts to incorporate highly sensitive thermal and electrical characterization capabilities to the system are ongoing.
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