Low-resistance Ni-based Schottky diodes on freestanding n-GaN
Corbett, Brian M.
Maaskant, Pleun P.
Schottky diodes formed on a low doped (5 x 10(16) cm(-3)) n-type GaN epilayer grown on a n(+) freestanding GaN substrate were studied. The temperature dependent electrical characteristics of Ni contacts on the as-grown material are compared with an aqueous, potassium hydroxide (KOH) treated surface. In both cases the diodes are dominated by thermionic emission in forward bias, with low idealities (1.04 at room temperature) which decrease with increasing temperature, reaching 1.03 at 413 K. The Schottky barrier height is 0.79 +/- 0.05 eV for the as-grown surface compared with 0.85 +/- 0.05 eV for the KOH treated surface at room temperature. This is consistent with an inhomogeneous barrier distribution. The specific on-state resistance of the diodes is 0.57 m Omega cm(2) The KOH treatment reduces the room temperature reverse leakage current density at -30 V to 1 x 10(-5) A cm(-2) compared to 6 x 10(-2) A cm(-2) for the as-grown samples. (C) 2007 American Institute of Physics. (DOI:10.1063/1.2799739)
Rectifiers , Interfaces , Transport , Contacts , Surface , Films , Schottky barriers , Surface treatments , Doping , Leakage currents , Electrical resistivity
Lewis, L., Corbett, B., Mahony, D. O. and Maaskant, P. P. (2007) 'Low-resistance Ni-based Schottky diodes on freestanding n-GaN', Applied Physics Letters, 91(16), pp. 162103. doi: 10.1063/1.2799739
© 2007 American Institute of Physics.This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. The following article appeared in Lewis, L., Corbett, B., Mahony, D. O. and Maaskant, P. P. (2007) 'Low-resistance Ni-based Schottky diodes on freestanding n-GaN', Applied Physics Letters, 91(16), pp. 162103 and may be found at http://aip.scitation.org/doi/abs/10.1063/1.2799739