Analysis of I–V characteristics on Au/n-type GaAs Schottky structures in wide temperature range

The current–voltage (I–V) characteristics of Au/n-GaAs Schottky barrier diodes (SBD) were determined in the temperature range 80–400 K. SBD parameters such as ideality factor n, series resistance RS and barrier height Φb were extracted from I–V curves using Cheungʹs method. The barrier height for current transport decreases and the ideality factor increases with the decrease temperatures. Such behavior is attributed to barrier inhomogeneities by assuming a Gaussian distribution of barrier heights at the interface. So that barrier height ΦI–V have been corrected by taking into account quality factors (n) and the electron tunneling factor (αχ1/2δ) in the expression of saturation current (I0) of the Au/n-GaAs Schottky diodes. Thus, a modified ln ( I 0 / T 2 ) − q 2 σ 0 2 / 2 k 2 T 2 versus 1/T gives Φ ¯ b0 ( T = 0 ) and A* as 0.73 eV and 11.08 A/(cm2 K2), respectively, without using the temperature coefficient of the barrier heights. Therefore, it has been concluded that the temperature dependent I–V characteristics of the device can be successfully explained with Gaussian distribution of the BHs.