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Meeting ID: 940 6691 2335
Passcode: 300041

In the past century, materials science and engineering brought about the revolutionization of airplanes (1903–present) and the invention of vacuum tubes (1904) and transistors (1947). Today, we face a wide range of engineering challenges from the end of Moore’s Law scaling to environmental pollution. Materials science and engineering has an important role in the manufacture of advanced materials for these applications. This effort will require materials synthesis, structural characterization, functional property measurement, and process mechanism understanding.

This presentation will describe a series of experiments that involve each of these elements. The first part will demonstrate epitaxy of core-shell Ge/GeSn nanowires for photonics applications and give some insights on the growth mechanism. The second part will focus on structural characterization of these nanowires—strain and Sn composition in GeSn play an important role in its optoelectronic properties. The third part will describe an application of electrochemical impedance spectroscopy to measurement of electrical defects at high-aspect-ratio semiconductor-oxide interfaces. The last part will apply in-situ gas cell TEM to the oxidation of Pt/Pd/Al2O3 automotive emissions catalyst to demonstrate that process monitoring can give important insights on underlying structural evolution mechanisms. Combining in-situ TEM with growth and functional property measurements will vertically integrate the different aspects of manufacturing advanced materials and can be an incredibly powerful method for understanding fabrication processes.