Schottky characteristics of Pt contacts on (11–22) semipolar n-type GaN grown on m-plane sapphire substrates

Abstract

The Schottky characteristics of Pt contacts fabricated on (11-22) semipolar n-type GaN were investigated. The saturation current density and the ideality factors obtained using the thermionic emission model were as large as 2.2 × 10 −3 A/cm 2 and 2.19, respectively, as a result of the strong leakage components in the currentvoltage curves. The barrier inhomogeneity model applied to the temperature dependent electrical data exhibited a mean barrier height of 1.1 eV with a large standard deviation of 169 meV. The thermionic field emission model yielded reliable Schottky parameters including a tunneling parameter of 0.054 eV and a Schottky barrier height of 1.23 eV.

Temperature dependent electrical characteristics of Pt Schottky barriers fabricated on lightly and highly doped n-type 4H-SiC

“…8) However, the thermionic field emission (TFE) mechanism not only has been found to dominate the reverse current of Schottky diodes on SiC, 10,11) but has recently been proposed to explain the above non-ideal observations for the Schottky diode on even lightly doped semiconductor. [12][13][14] In this study, we systematically compare the temperature dependent electrical properties of Pt Schottky barriers fabricated on lightly and relatively highly doped 4H-SiC (1 × 10 16 and 1 × 10 18 cm −3 ) deduced from current-voltage-temperature (I-V-T) on the assumption of TE and TFE models, and capacitance-voltage-temperature (C-V-T ) measurements, respectively. The comparisons show that although the temperature dependence of qϕ Bn and n obtained from the TE model for the highly doped sample can be explained by a Gaussian distribution of barrier heights, the TFE model is more appropriate in explaining the electrical transport.…”

Improved Performance of (112̄2) Semipolar InGaN/GaN Light-Emitting Diodes Grown Using a Hemispherically Patterned SiO2 Mask

“…4) Therefore, the radiative recombination lifetime in the films increases, which raises the probability of nonradiative recombination and decreases the achievable internal quantum efficiency in InGaN/GaN QWs. 5,6) To solve these problems, many research groups have studied nonpolar [7][8][9] and semipolar GaN and InGaN/GaN LEDs, [10][11][12] which could reduce polarization-induced electrostatic fields. In particular, the specific features of (11 22) semipolar InGaN/ GaN structures are emphasized, which can be beneficial for improving the optical and transport properties of quantumwell based light-emitting devices in comparison with those of nonpolar structures.…”