Influence of AlN and GaN Pulse Ratios in Thermal Atomic Layer Deposited AlGaN on the Electrical Properties of AlGaN/GaN Schottky Diodes

Abstract

Atomic layer deposited AlGaN with different AlN and GaN pulse ratios (2:1, 1:1, and 1:2) was used to prepare AlGaN/GaN Schottky diodes, and their current transport mechanisms were investigated using current–voltage (I–V) and capacitance–voltage (C–V) measurements. Under low reverse bias condition, the sample with the pulse ratio of 2:1 was explained by Poole–Frenkel emission and the negative temperature dependence for the sample with the pulse ratio of 1:2 was associated with the acceptor levels in the AlGaN layer. Fast interface traps at 0.24–0.29 eV were observed for the samples with the pulse ratios of 1:1 and 1:2, whereas bulk traps at ~0.34 eV were observed for the sample with the pulse ratio of 2:1. Higher trap densities were obtained from the C–V hysteresis measurements when the pulse ratios were 1:1 and 1:2, indicating the presence of a charge trapping interfacial layer. According to the X-ray photoelectron spectroscopy spectra, the pulse ratio of 2:1 was found to have less oxygen-related defects in the AlGaN layer.

G-Doping-Based Metal-Semiconductor Junction

“…This can explain why I R reduction is more pronounced in p + -type substrates. The Si-based G-doped Schottky diodes I-V curves are comparable to I-V curves obtained on the basis of more advanced materials (AlN and GaN) [27]. Further improvement of G-doping-based junctions can be made by tuning the Fermi level using nanograting depth variation [22].…”

Ultrahigh-gain colloidal quantum dot infrared photodetectors: Unraveling the potential of electro-kinetically pumped charge multiplication

“…The potential barrier height decreased with the increase in the reverse bias in the CQD-based IRPDs. Upon reaching a reverse bias of 10 V, the activation energy transitioned from positive to negative, indicating that the internal potential assisted the transfer of conduction electrons in the CQD-based IRPDs 30 . When the reverse bias exceeded 14 V, a noticeable increase in the current was observed, despite the saturation of the activation energy.…”

Atomic layer deposition and application of group III nitrides semiconductor and their alloys

“…借助于ALD可调节合金薄膜禁带宽度的特 点, 对基于相关薄膜器件的设计非常有利. Kim 等 [101][102][103] 在2020年发表了多篇文章报道了ALD 沉积AlGaN/GaN肖特基二极管的电流传输机制. 他们首先在GaN衬底上用ALD沉积了不同厚度 的AlGaN形成肖特基二极管, 并对其电子传输机 制进行了详细的研究 [101] .…”

“…Kim 等 [101][102][103] 在2020年发表了多篇文章报道了ALD 沉积AlGaN/GaN肖特基二极管的电流传输机制. 他们首先在GaN衬底上用ALD沉积了不同厚度 的AlGaN形成肖特基二极管, 并对其电子传输机 制进行了详细的研究 [101] . 结果显示, 在348 K以 AlGaN/GaN肖特基二极管 [102] .…”