Date Thesis Awarded
Bachelors of Science (BS)
This project focused on ellipsometry, using it to find optical properties of sapphire, and designing a vacuum chamber to expand the temperature range in which we can perform ellipsometry. First, we obtained the anisotropic optical constants of an m-plane sapphire substrate using reflectance ellipsometry and transmission intensity measurements between 0.6 eV and 6.0 eV with a Woollam Inc. variable-angle spectroscopic ellipsometer. These anisotropic optical constants of m-plane sapphire could be used in the future to aid in modeling layered systems where the sapphire is used as a substrate for growing thin film samples of transition metal oxides.
Second, we designed and tested an ultra-high vacuum chamber to enable us to perform variable angle cryogenic ellipsometry measurements. The vacuum chamber was designed for reflection and transmission ellipsometry, as well as near-normal incidence reflection measurements at cryogenic temperatures down to 4K. This will give us new experimental capabilities allowing us to obtain data in temperature ranges that have rarely been probed with ellipsometry. We also designed and constructed a vertical translation stage, as well as a combination horizontal translation and tilt stage to allow us to align the sample for ellipsometry measurements.
Hollingshad, Arlough, "Spectroscopic Ellipsometry and Cryogenic Capability" (2014). Undergraduate Honors Theses. Paper 13.