Department of Materials Science and Engineering, Technion-Israel Institute of Technology , Haifa 3200003, Israel.
Department of Materials Science and Engineering, Stanford University , Stanford, California 94305, United States.
ACS Appl Mater Interfaces. 2016 Jul 6;8(26):16979-84. doi: 10.1021/acsami.6b02957. Epub 2016 Jun 23.
One of the main challenges in the path to incorporating InGaAs based metal-oxide-semiconductor structures in nanoelectronics is the passivation of high-k/InGaAs interfaces. Here, the oxygen scavenging effect of thin Ti layers on high-k/InGaAs gate stacks was studied. Electrical measurements and synchrotron X-ray photoelectron spectroscopy measurements, with in situ metal deposition, were used. Oxygen removal from the InGaAs native oxide surface layer remotely through interposed Al2O3 and HfO2 layers observed. Synchrotron X-ray photoelectron spectroscopy has revealed a decrease in the intensity of InOx features relative to In in InGaAs after Ti deposition. The signal ratio decreases further after annealing. In addition, Ti 2p spectra clearly show oxidation of the thin Ti layer in the ultrahigh vacuum XPS environment. Using capacitance-voltage and conductance-voltage measurements, Pt/Ti/Al2O3/InGaAs and Pt/Al2O3/InGaAs capacitors were characterized both before and after annealing. It was found that the remote oxygen scavenging from the oxide/semiconductor interface using a thin Ti layer can influence the density of interface traps in the high-k/InGaAs interface.
将基于 InGaAs 的金属氧化物半导体结构纳入纳米电子学的主要挑战之一是高介电常数/InGaAs 界面的钝化。在这里，研究了薄 Ti 层对高介电常数/InGaAs 栅堆叠的氧清除效应。使用了原位金属沉积的电学测量和同步辐射 X 射线光电子能谱测量。通过插入的 Al2O3 和 HfO2 层远程去除 InGaAs 本征氧化物表面层中的氧。同步辐射 X 射线光电子能谱显示，在 Ti 沉积后，InGaAs 中 InOx 特征的强度相对于 In 降低。退火后，信号比进一步降低。此外，Ti 2p 光谱清楚地显示了在超高真空 XPS 环境中薄 Ti 层的氧化。使用电容-电压和电导-电压测量，对 Pt/Ti/Al2O3/InGaAs 和 Pt/Al2O3/InGaAs 电容器进行了退火前后的特性分析。结果发现，使用薄 Ti 层从氧化物/半导体界面远程清除氧可以影响高介电常数/InGaAs 界面中的界面陷阱密度。
