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121.
用X射线衍射及I—V测量技术研究了W在Al/TiSi_2/Si接触系统中的作用,并与不加W阻挡层的情况作了比较。热稳定性的研究表明:在高达100℃退火时,W阻挡层能够阻止Al与TiSi_2的完全反应。对Al/W/TiSi_2/Si接触二极管的I—V测试表明,在480℃以内退火,势垒高度变化不大。当退火温度达500℃时,Si通过TiSi_2层扩散至W阻挡层而使之失效. 相似文献
122.
Ag/InP Schottky结是制作TE场助光电阴极的关键,本文利用Auger分析技术,详细地研究了热处理对Ag/InPSchottky结界面特性的影响。实验结果表明高温长时间热处理会导致严重界面相互扩散,同时使Schottky结的势垒高度降低,理想因子增大,泡利负电性理论很好地解释了扩散效应。势垒高度的降低及理想因子的增大也是由界面互扩散造成的,这种扩散导致界面特性由Schotthy特性向欧姆性质转化。为防止界面互扩散及Schottky结特性的退化,可选用负电性小的金属制作Schottky结,并在工艺上尽量减少热处理的温度和时间。 相似文献
123.
T. L. Cheeks T. Sands R. E. Nahory J. P. Harbison H. L. Gilchrist V. G. Keramidas 《Journal of Electronic Materials》1991,20(7):881-884
Enhancement of the Schottky barrier height was obtained in MBE grown (CoAl or NiAl)/ AlAs/GaAs heterostructures by incorporating
ultra thin AlAs layers between the metal and GaAs. By varying the AlAs thickness from 0 to 10 nm the effective barrier height,
determined by current-voltage and capacitance-voltage measurements, could be tailored from 0.76 eV to 1.1 eV. Internal photoemission
measurements were performed to verify the 1.1 eV barrier height. The temperature dependence of the current-voltage characteristics
showed that thermionic emission was the dominant transport mechanism for all thicknesses of AlAs. The results were consistant
with transport through the X-band of AlAs. 相似文献
124.
Q. Wahab M. Karlsteen M. Willander J -E. Sundgren 《Journal of Electronic Materials》1991,20(11):899-901
β-SiC thin films have been grown on (100) silicon substrates using reactive magnetron sputtering of a silicon target in an
Ar/CH4 mixed plasma. For the first time it has been possible to make gold Schottky diodes on β-SiC grown by reactive magnetron sputtering.
Current-voltage measurements showed an ideality factor of 1.27 and a leakage current density of 4 μA/cm2. Capacitance-voltage measurements gave a barrier height of 1.04 eV. The static dielectric constant for β-SiC was determined
to be 9. 相似文献
125.
Electrical measurements have been reported sandwich device fabricated from DNA molecular film located between Al and p-type InP inorganic semiconductor. We have observed that DNA-based this structure shows an excellent rectifying behavior, and that the DNA film increases the effective barrier height by influencing the space charge region of InP. We have also evaluated electrical characteristics of the DNA-based device in a wide temperature range. 相似文献
126.
A. T. Ping A. C. Schmitz I. Adesida M. Asif Khan Q. Chen J. W. Yang 《Journal of Electronic Materials》1997,26(3):266-271
Dry etch-induced damage has been investigated using Pd Schottky diodes fabricated on n-type GaN surfaces that were etched
by reactive ion etching in SiCl4 and Ar plasmas. Damage was evaluated by measuring the current-voltage, current-voltage-temperature, and capacitance-voltage
characteristics of the diodes. A plasma chemistry that includes a chemical etching component (SiCl4) was found to significantly reduce the degree of induced damage in comparison to a chemistry that uses only a physical component
(Ar). The effective barrier height, ideality factor, reverse breakdown voltage, reverse leakage current, and the effective
Richardson coefficient of diodes etched under various plasma conditions are presented. The degree of etch-induced damage was
found to depend strongly on the plasma self-bias voltage but saturates with etch time after an initial two-minute etch period.
Rapid thermal annealing was found to be effective in improving the diode characteristics of the etched GaN samples. 相似文献
127.
J.F. Sánchez-Royo J. Pellicer-Porres S.J. Gilliland A. Chevy 《Surface science》2007,601(18):3778-3783
The electronic properties of InSe/M (M Pd, Au) interfaces have been studied by X-ray photoemission measurements. For the InSe/Pd interface, it has been found that Pd atoms diffuse into the InSe lattice at early stages of Pd coverage, acting as acceptor centers. As the Pd coverage increases, a Pd-InSe reaction determines the electronic behaviour of the interface. However, for Pd coverages higher than 1 ML, the barrier formation tends to be controlled by an emerging bulklike Pd overlayer. Despite the atomic structure of this system is far from that expected for an ideal Schottky one, the final electronic barrier value is close to that expected for an abrupt InSe/Pd Schottky interface. On the contrary, the InSe/Au system appeared to behave as a quasi-ideal abrupt Schottky interface. Annealing processes performed at temperatures higher than 600 K alter this scheme, as revealed by X-ray absorption spectroscopy measurements, enhancing diffusion of Au atoms into InSe. In any case, the electronic barrier results to be determined by the Au overlayer formed. 相似文献
128.
P. Servati A. Colli S. Hofmann Y.Q. Fu P. Beecher Z.A.K. Durrani A.C. Ferrari A.J. Flewitt J. Robertson W.I. Milne 《Physica E: Low-dimensional Systems and Nanostructures》2007,38(1-2):64
This paper presents photodetectors having vertically stacked electrodes with sub-micron (300 nm) separation based on silicon nanowire (SiNW) nanocomposites. The thin-film-like devices are made using standard photolithography instead of electron beam lithography and thus are amenable to scalable low-cost manufacturing. The processing technique is not limited to SiNWs and can be extended to different nanowires (NWs) (e.g., ZnO, CdSe) and substrates. The current–voltage characteristics show Schottky behaviour that is dependent on the properties of the contact metal and that of the pristine SiNWs. This makes these devices suitable for examination of electronic transport in SiNWs. Preliminary results for light sensitivity show promising photoresponse that is a function of effective NW density. 相似文献
129.
Weimin Hou Li Chen Maoyou Yang Mingjian Zhang Junmei Wang Jiakuo Shi Shuo Su Duo Zhang Hongping Wu 《Annalen der Physik》2023,535(7):2300061
Based on the first-principles calculation, the effect of intercalated LiF on the contact characteristics of the interface between Au electrode and MoS2 layer is studied. It is found that adding LiF film can change the contact type between metal electrode Au and MoS2 layer from Schottky contact to ohmic contact, which is accompanied by interfacial charge transfer from LiF layer to MoS2 layer and the downward movement of d (dxy and dz2) orbital of Mo atom and p (px and py) orbital of S atom to Fermi level. And the interlayer spacing between LiF layer and Au electrode has a great impact on the interface contact characteristics. The electric field effect and stress effect of interface contact of Au, LiF and MoS2 (Au/LiF/MoS2)is more obvious than that of interface contact of Au and MoS2 (Au/MoS2). Au/LiF/MoS2 shows ohmic contact with the interlayer spacing between Au layer and LiF layer less than 3.05 Å and with the electric field less than 0.15 VÅ−1, respectively, while Au/MoS2 still shows N-type Schottky contact. These findings are helpful to control the contact resistance and have guiding significance for high performance MoS2 field effect transistor and other electronic components. 相似文献
130.
有限长线接触弹流润滑研究的现状与展望 总被引:4,自引:8,他引:4
在已有的研究工作积累文献调研的基础上,对有限长线接触弹流润滑研究的形成背景、发展过程、研究现状及其应用等进行了简要的综合介绍与分析评述,并指出了现有的研究工作的特点、存在的问题和进一步研究的主政方向及其必要性,展望了这方面研究工作的发展前景。 相似文献