Schottky barriers and contact resistances on p-type GaN

Abstract

We measured the Schottky barrier heights and specific contact resistivities of four different metals on p-type GaN. The Schottky barrier heights of Pt, Ni, Au, and Ti were obtained from the current-voltage characteristics to be 0.50, 0.50, 0.57, and 0.65 eV, respectively. The specific contact resistivities were 0.013, 0.015, 0.026, and 0.035 Ω⋅cm2, respectively. Our experimental results proved that the Schottky barrier heights and specific contact resistivities decrease with increase in metal work function as expected theoretically.

Schottky barrier formation at the Au to rare earth doped GaN thin film interface

“…Kurtin et al [32] suggested that the Schottky barrier height on GaN should depend directly on the work function or electronegativity difference between the metal electrode and GaN. Foresi and Moustakas [33] observed this direct correlation experimentally, while Guo et al [34] and Mori et al [35] observed only a weak dependence of the Schottky barrier height on the metal work function for n-type GaN and p-type GaN, respectively. The 1998 review of metal-GaN contact technology by Liu and Lau [19] reported that, for a variety of contact metals with both low and high work functions, Schottky barrier heights at the metal-GaN interface varied with metal work function, within the experimental scatter.…”

Competition between deep impurity and dopant behavior of Mg in GaN Schottky diodes

“…[7][8][9][21][22][23][24] The activation energy of the Mg acceptor level is taken at ͑ E t -E v )ϭ0.16 eV. The Schottky barrier height q b is taken 0.70 eV.…”

Carrier Transport Phenomena in Metal Contacts to AlInGaN-Based Laser Diodes

“…11, contact resistivity rapidly decreases as increase in the defect density, and it also decreases when the qφ decreases. In order to obtain the defect density in the p-GaN films, the qφ was measured by using the devised I-V method which utilizes large-area contacts and reverse-biased I-V characteristics, [39] and the measured qφ was 0.36 eV. From the measured Fig.…”