Electronic Characteristics of Rare Earth Doped GaN Schottky Diodes
Abstract
The Schottky barrier height (SBH) was measured on GaN based diodes with three different dopant types; Gd, Er and Yb. Two methods were used to determine the SBH. The first method was the Juergen Werner method to evaluate the I-V characteristics. The calculated SBH of the diodes using this method was 1.41 +/- 0.20eV, 1.71 +/- 0.25eV and 1.75 +/- 0.28eV for the Gd-, Er- and Yb-doped diodes respectively. It was observed that using an ad-hoc effective Richardson constant value of 0.006Axcm(-2)xK(-2) to calculate the SBH rendered results that were in no greater than 2% disagreement (neglecting error) with photoemission spectroscopy measurements performed on the same GaN thin films by a another researcher a year prior. The second method of measuring the SBH was the temperature dependent I-V-T measurements using the modified Norde function. The calculated SBH of the diodes were universally lower than the results of the Juergen Werner method. The SBH was 1.19 +/- 0.12eV, 1.39 +/- 0.16eV and 1.43+/- 0.12eV for the Gd-, Er- and Yb-doped diodes respectively. Additionally, the Norde method provided direct calculation of the effective Richardson constants, which were 0.011 +/- 0.001Axcm(-2)xK(-2), 0.036 +/- 0.003Axcm(-2)xK(-2) and 0.021 +/- 0.02Axcm(-2)xK(-2) for the Gd-, Er- and Yb-doped diodes respectively. Both measurements in this study are in agreement with the earlier photoemission spectroscopy measurements with regard to the proportional differences among the different dopant types.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 21, 2013
- Accession Number
- ADA582470
Entities
People
- Aaron B. Blanning
Organizations
- Air Force Institute of Technology