RESEARCH
HIGH-SPEED MICROCANTILEVER TESTING
Nanomechanical properties of thin-films are evaluated using an ultrasonically-actuated high-speed microcantilever oscillating in the gigahertz frequency range. This study involves laser-interferometric detection of the microcantilever's natural frequency and quantification of material properties via finite element analysis.
ULTRAFAST LASER METROLOGY
？Light-matter interactions are investigated to understand thermal transport phenomena in nanoscale materials. Taking advantage of the ultrashort width of laser pulses generated by a femtosecond laser system, the time-domain thermoreflectance (TDTR) technique is employed to quantify thermal conductivity and thermal boundary resistance of semiconductor thin-films.
SURFACE ACOUSTIC WAVE SPECTROMETRY
Mechanical properties and ultrasound propagation behaviors in thin-films are studied using the surface acoustic wave spectrometry. Unlike traditional contact-mechanics based testing methods, materials are nondestructively characterized with higher resolution and accuracy.
SURFACE WAVINESS EVOLUTION
Periodic wavy nanopatterns are non-photolithographically generated on thin-films. Examples of specific material systems are self-assembly of silicon-germanium quantum dots on a silicon substrate and thin metallic films on a thermoresponsive shape memory polymer foundation. Applications are cell-growth templates, microfluidic substrates, and backreflectors of photovoltaic devices.