Description |
TITLE: COHERENT X-RAY SCATTERING STUDIES OF ION BEAM NANO-PATTERNING KINETICS AND
DYNAMICS
ABSTRACT: Spontaneous formation of nanoscale morphologies or ultrasmoothening is observed
when 0.1-10 keV energetic ions bombard a surface. Since the length scales of the nanopatterns are in tens of nanometers, X-rays can be utilized not only to characterize them, but also to study kinetics and dynamics happening on the surface in real time. We use the surface sensitive X-ray technique of Grazing-Incidence Small-Angle X-ray Scattering (GISAXS), and the resulting measurements are compared with theoretical models that attempt to explain the ion beam nano-patterning processes. By using non-coherent and coherent X-rays, in-situ studies of Si, Ge, and SiO2 surfaces, bombarded by ions, have been conducted. Non-coherent X-rays can be used to discern the averaged kinetics on a surface, but coherent X-rays further enable us to differentiate fluctuations around the average kinetics. As a complementary measurement, Multi Beam Optical Stress Sensor (MOSS) is also used to do real-time measurements of the stress evolution during nanoscale pattern formations. Python analysis pipelines that have been independently developed to analyze GISAXS and MOSS data will be discussed.
COMMITTEE: ADVISOR
Professor Karl Ludwig, MSE/Physics; Professor Kevin Smith, MSE/Physics; Professor Soumendra N. Basu, MSE/ME; Professor William Klein, Physics |