Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1808682 | Physica B: Condensed Matter | 2016 | 5 Pages |
Abstract
In this study, the current-voltage (I-V) and capacitance-voltage (C-V) characteristics of Au/n-GaAs Schottky diodes have been measured over a wide temperature range, 80-480Â K. The diodes were rectifying throughout the range and showed good thermal stability. Room temperature values for the ideality factor, I-V barrier height and C-V barrier height were found to be n=1.10, ÏIV=0.85Â eV and ÏCV=0.96Â eV, respectively. ÏIV increases and n decreases with an increase in temperature. We investigated the effect of elevated temperatures on the barrier height and ideality factor by measuring the diodes at a high temperature (annealing mode) then immediately afterwards measuring at room temperature (post annealing mode). The measurements indicate I-V characteristics that degrade permanently above 300Â K. Permanent changes to the C-V characteristics were observed only above 400Â K. We also noted a discrepancy in the C-V barrier height and carrier concentration between 340 and 400Â K, which we attribute to the influence of the EL2 defect (positioned 0.83Â eV below the conduction band minima) on the free carrier density. Consequently, we were able to fit the ÏCV versus temperature curve into two regions with temperature coefficients â6.9Ã10â4Â eV/K and â2.2Ã10â4Â eV/K above and below 400Â K.
Keywords
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Condensed Matter Physics
Authors
S.M. Tunhuma, F.D. Auret, M.J. Legodi, M. Diale,