Determination of the mean and the homogeneous barrier height of Cu Schottky contacts on heteroepitaxial β-Ga2O3 thin films grown by pulsed laser deposition
Determination of the mean and the homogeneous barrier height of Cu Schottky contacts on heteroepitaxial β-Ga2O3 thin films grown by pulsed laser deposition
复制标题
DOI：
10.1002/pssa.201330088
复制
发表时间：
2014-01-01
影响因子：
2
通讯作者：
Grundmann, Marius
中科院分区：
文献类型：
--
作者：
Splith, Daniel;Mueller, Stefan;Grundmann, Marius
我们研究了脉冲激光沉积(PLD)生长的(201)取向Ga2O_3薄膜上的铜肖特基接触(SCS)的电学性质。两种不同样品结构的I-V特性表现出2V至7个数量级的整流比。主要的电流传输机制是热离子发射。通过对I-V特性的拟合，得到了在50~320K温度范围内的理想因子n和有效势垒高度phi Beff。考虑到高斯势垒高度分布，我们确定了平均势垒高度为1.32 eV。这些触点在至少550K的高温下是稳定的。在此温度下，发现了1.32 eV的均匀势垒高度，与测定的平均势垒高度一致。此温度的理想系数为1.03，势垒不均匀不影响电流传输，使接触接近理想状态。图为550K时铜/β-Ga2O3肖特基接触的示意图。插图显示了样品的照片图像。(C)2013 Wiley-VCH Verlag GmbH&Co.KGaA，Weinheim
We have investigated the electrical properties of Cu Schottky contacts (SCs) on (201)-oriented -Ga2O3 thin films, which have been grown by pulsed laser deposition (PLD). The I-V characteristics of two different sample structures exhibit rectification ratios at 2V up to 7 orders of magnitude. The dominant current transport mechanism is thermionic emission. By fitting the I-V characteristics, we obtained the ideality factor n and the effective barrier height phi Beff at temperatures between 50 and 320K. Considering a Gaussian barrier height distribution, we determined a mean barrier height of 1.32eV. The contacts are stable at high temperatures up to at least 550K. At this temperature a homogeneous barrier height of 1.32eV is found, consistent with the determined mean barrier height. The ideality factor for this temperature is 1.03 and barrier inhomogeneities do not influence current transport, making the contact close to ideal.Schematic band diagram of a Cu/beta-Ga2O3 Schottky contact at a temperature of 550 K. The inset shows a photographic image of the sample.(C) 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim