@article{ijp2013123,
author={{Abdalla, S. and Marzouki, F. and Al-ameer, S. and Turkestani, S.},
title={Electric Properties of n-GaN: Effect of Different Contacts on the Electronic Conduction},
journal={International Journal of Physics},
volume={1},
number={2},
pages={41--48},
year={2013},
url={http://pubs.sciepub.com/ijp/1/2/3},
abstract={The forward current¨Cvoltage (I¨CV) characteristics of n-GaN films on sapphire substrate are investigated over a temperature range of 80¨C300K, using two different types of metal/semiconductor contacts: Al/GaN and Au/GaN. Samples with Al metallic contacts show well defined ohmic behavior with linear forward and reverse I-V characteristics indicating no potential barrier. These measurements made at temperatures in the range 77K-300K show the influence of two donor levels: one is deep at 0.23ev, while the other is shallow at 0.013ev below the conduction band. These values have been confirmed by DSCL measurements and the density of electrons <i>n</i><SUB>0</SUB> is calculated as a function of temperature and found that <i>n</i><SUB>0</SUB> = 3.08x10^<SUP>14</SUP>cm<SUP>-3 </SUP>at 300K. Besides, the mobility of electrons ¦Ì has been calculated as a function of temperature and have been found that at 300K: ¦Ì = 175cm2/v.s. On the other hand, resistively deposited Au Schottky contacts on n-type GaN show net rectification behavior. In contrast to the published data, the I-V measurements revealed that these Au contacts exhibited bad rectification properties: relatively high reverse current and bad ideality factor (n = 11.5 at 80K). This discrepancy has been attributed to the presence of a series resistance with the Au/n-GaN Schottky diode. The potential drop across this resistance decreases n from 11.5 down to a logic value 1.2 at 80K. Index Terms¡ªGaN diode; contact resistance; ideality factor; transport mechanism.},
doi={10.12691/ijp-1-2-3}
publisher={Science and Education Publishing}
}