Hope College Department of Physics and Engineering
Research Experiences for Undergraduates
Summer 2005
Project Summary

 

Project Title:

Optical and Electrical Properties of ScN

Student Name: Andrew Moore
Student's Home Institution: Hope College
Research Advisor: Dr. Mark Little
Source of Support: NSF-REU, Research Corporation

A series of ScN samples were grown on c-plane sapphire from room temperature to 800o C. Mobility, resistivity, and carrier density were measured for each sample. Resistivity decreased (from ~107 to ~1 ?-cm) and carrier density increased with increased growth temperature. Rutherford backscattering revealed oxygen was incorporated during growth but decreased in concentration with increased growth temperature. From this it can be seen that the sheet resistance is proportional to the amount of oxygen in the sample. Optical absorption measurements show the band gap to be 2.81±0.16 eV, slightly higher then the 2.1 eV expected for ScN. High growth temperature samples had a distinct strong absorption edge at ~ 3.3 eV. The origin of this edge is under investigation.