MSE Seminar: Michael Presley, The Formation of Amorphous and Crystalline Damage in Metallic and Semiconducting Materials under Gallium Ion Irradiation

PhD Candidate advised by Dr. Hamish Fraser

All dates for this event occur in the past.

477 Watts Hall
2041 College Rd
Columbus, OH 43210
United States

Abstract

Gallium ion irradiation in dual-beam FIB microscopes is well known to cause some degree of damage during the milling process, obscuring features of interest in the TEM. Geometrical limitations inherent in thin foils have made quantitative measurement of the damage layer difficult and time consuming. By adapting the needle geometry used for atom probe, these limitations can be bypassed and measurements made rapidly and in parallel with traditional TEM foils. HRTEM analysis of several metals, semiconductors, and intermetallics reveal two distinct regimes of damage response: amorphous and defect dominated. The effects of these two regimes on HAADF-STEM and TEM imaging was examined, and steps necessary to identify and minimize damage in FIB produced foils will be presented.