Electrical Properties Of Ir/n-InGaN/Ti/Al Schottky Barrier Diode In A Wide Temperature Range
R. Padma, V. Rajagopal Reddy
Volume 5, Issue 1, Page 31-38 | DOI: 10.5185/amlett.2013.6503
Ir Schottky contact; n-type InGaN; Electrical characteristics; Schottky barrier heights; Series resistance; Poole-Frenkel and Schottky emissions.
The temperature dependent current-voltage (I-V) and capacitance-voltage (C-V) characteristics of Ir/n-InGaN Schottky contacts have been investigated and analysed in the temperature range of 100-400 K. The estimated barrier heights and ideality factor of Ir/n-InGaN Schottky diode are 0.30 eV (I-V), 1.15 eV (C-V) and 3.05 at 100 K, and 0.94 eV (I-V), 0.97 eV (C-V) and 1.20 at 400 K respectively. The barrier height (Φb), ideality factor (n) and series resistance (RS) of Ir/n-InGaN Schottky diode are also evaluated using Cheung’s and Norde methods. Results show that the barrier heights (I-V) increase while ideality factor and series resistance decease with increasing temperature. Further, the discrepancy between Schottky barrier heights estimated from I-V and C-V measurements is also explained. It is observed that the interface state density Nss decreases with an increasing temperature. Experimental results showed that the conduction current is dominated by Poole-Frenkel emission in the temperature range from 100 K to 340 K and by Schottky emission above 340 K. The dominate conduction mechanism changed from Poole-Frenkel to Schottky emission in the temperature range from 340 K to 370 K. Finally, it is concluded that the temperature-dependent I–V characteristics of the Ir/n-InGaN Schottky diode can be successfully explained on the basis of thermionic emission (TE) mechanism. Copyright © 2014 VBRI press.