Hope College Department of Physics and Engineering
Research Experiences for Undergraduates
Project Title: Backscattering and RBS in Thin-film Semiconductors
Student Name: Andrew Jarosz
Students' home institutions: Hope College
Research Advisor(s): Dr. Mark Little
Source of Support: Research Corp
The goal of this project was to analyze the properties and composition of thin films using techniques such as spectrum absorption and Rutherford backscattering. We grew a number of thin film semiconductors using a sputtering technique, and proceeded to test them for their band gaps and composition. By finding an absorption spectrum, and plotting the results in a Tauc plot, we were able to easily find the band gap of each sample, along with getting a better idea of whether the sample was amorphous or crystalline. We found our average band gap in scandium nitride to be about 2.56 eV, and began getting data on gallium nitride films. Through Rutherford backscattering, we are able to find the thickness and composition of the film, along with information regarding the distribution of the particles in the film. Results from backscattering experiments are yet to be determined. No conclusions have yet been reached concerning the growth of the films and their properties, but more data is expected as the experiment progresses and more films are grown. Ideally, with the expected RBS data and more films to sample, we will soon be able to reach solid conclusions.