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11.
M. A. Dornath-Mohr M. W. Cole H. S. Lee D. C. Fox D. W. Eckart L. Yerke C. S. Wrenn R. T. Lareau W. H. Chang K. A. Jones F. Cosandey 《Journal of Electronic Materials》1990,19(11):1247-1255
Low temperature, non-alloyed Au-Ge contact formation ton-GaAs is a multi-step pro-cess. During the first 5 min of annealing at 320° C the Au and Ge segregate into regions a few microns
in size and extend over the entire thickness of the metal layer and sig-nificant in-diffusion of the Au and Ge and out-diffusion
of the Ga and As occurs. This intermixing reduces the barrier height from 0.75 to 0.40 eV. The contact does not show ohmic
behavior until it has been annealed for 3 hr. During this time Ge continues to in-diffuse but at a slower rate than it did
initially. The rate of Ge in-diffusion is en-hanced by the presence of Au since samples containing less Au require longer
anneals to show ohmic behavior and have higher specific contact resistances. The presence of excess As, which is prevented
from evaporating by a Si3N4 cap has the opposite effect since capped layers have higher specific contact resistances. Au-Ge phases appear after approximately
3 hr of annealing, therefore, Au-Ge phases cannot be responsible for the reduction in barrier height. The interface morphology
is smooth, differing from that of pure Au and alloyed contacts that often contain spiking of the metals into the semi-conductor.
The orientation relationship for the Au grains differs from that of pure Au.
Work performedat U.S. Army ETDL, Fort Monmouth, NJ 07703.
Work performed at U.S.Army ETDL, Fort Monmouth, NJ 07703. 相似文献
12.
4H-SiC Schottky barrier diodes (SBDs) were fabricated and characterized from room temperature to 573 K using HfNxBy as Schottky electrodes. The results are compared to SBDs fabricated using other electrodes that include Ni, Pt, Ti and Au. The Schottky barrier height Φb for as-deposited HfNxBy/n−/n+ diodes, determined from room temperature current-voltage characteristics, is 0.887 eV. This is lower than those of SBDs fabricated using other metals such as Au, where Φb is 1.79 eV. The HfNxBy/n−/n+ diodes studied have a much higher on-resistance Ron of around 38.24 mΩ-cm2, which is about four times that of Au/n−/n+ diodes, due to the higher sheet resistance of the sputtered HfNxBy electrode layer. The barrier height Φb and ideality factor η of the HfNxBy/n−/n+ diodes remain almost unchanged after 400 and 750 °C anneal in N2. This suggests excellent thermal and chemical stability of HfNxBy in contact with 4H-SiC. 相似文献
13.
The defects induced by inductively coupled plasma reactive ion etching (ICP-RIE) on a Si-doped gallium nitride (GaN:Si) surface have been analyzed. According to the capacitance analysis, the interfacial states density after the ICP-etching process may be higher than 5.4 × 1012 eV−1 cm−2, compared to around 1.5 × 1011 eV−1 cm−2 of non-ICP-treated samples. After the ICP-etching process, three kinds of interfacial states density are observed and characterized at different annealing parameters. After the annealing process, the ICP-induced defects could be reduced more than one order of magnitude in both N2 and H2 ambient. The H2 ambient shows a better behavior in removing ICP-induced defects at a temperature around 500 °C, and the interfacial states density around 2.2 × 1011 eV−1 cm−2can be achieved. At a temperature higher than 600 °C, the N2 ambient provides a much more stable interfacial states behavior than the H2 ambient. 相似文献
14.
We report the Schottky performance and thermal reliability of a wide bandgap InGaP layer in contact with a Cu/Au metallic
system. An effective Schottky barrier height of 0.97 eV and an ideality factor of 1.21 can be achieved. The thermal reliability
of the resultant Schottky barrier diodes was analyzed using Auger electron spectroscopy and atomic force microscopy. The thermal
reliability could be main tained up to 450°C. The failure mechanism was attributable to the decomposition of the InGaP layer
and the interdiffusion of the chemical elements at higher temperature. Insensitive photoresponsivity with the in cident optical
power was found for the resultant Au/Cu-metal-semiconductor-metalphotodetectors (MSM-PDs). According to the measured temporal
response of the Au/Cu-MSM-PDs, the operation frequency could be above 10 GHz. 相似文献
15.
Poly (linoleic acid)-g-poly(methyl methacrylate) (PLiMMA) graft copolymer was synthesized and characterized. PLiMMA graft copolymer was synthesized from polymeric linoleic acid peroxide (PLina) possessing peroxide groups in the main chain by free radical polymerization of methyl methacrylate. Later, PLiMMA was characterized by proton nuclear magnetic resonance (1H NMR), gel permeation chromatography (GPC), thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC) techniques. Furthermore, Au/PLiMMA/n-Si diode was fabricated for the purpose of investigating PLiMMA׳s conformity in diodes. The main electrical characteristics of this diode were investigated using experimental current–voltage (I–V) measurements in dark and at room temperature. Obtained results, such as sufficiently high rectifying ratio of 4.5×104, indicate that PLiMMA is a promising organic material for electronic device applications. 相似文献
16.
The influence of high energy electron (HEE) irradiation from a Sr-90 radio-nuclide on n-type Ni/4H–SiC samples of doping density 7.1×1015 cm−3 has been investigated over the temperature range 40–300 K. Current–voltage (I–V), capacitance–voltage (C–V) and deep level transient spectroscopy (DLTS) were used to characterize the devices before and after irradiation at a fluence of 6×1014 electrons-cm−2. For both devices, the I–V characteristics were well described by thermionic emission (TE) in the temperature range 120–300 K, but deviated from TE theory at temperature below 120 K. The current flowing through the interface at a bias of 2.0 V from pure thermionic emission to thermionic field emission within the depletion region with the free carrier concentrations of the devices decreased from 7.8×1015 to 6.8×1015 cm−3 after HEE irradiation. The modified Richardson constants were determined from the Gaussian distribution of the barrier height across the contact and found to be 133 and 163 A cm−2 K−2 for as-deposited and irradiated diodes, respectively. Three new defects with energies 0.22, 0.40 and 0.71 eV appeared after HEE irradiation. Richardson constants were significantly less than the theoretical value which was ascribed to a small active device area. 相似文献
17.
Taron Makaryan Yasuaki Okada Hiroyuki Kondo Seiji Kawasaki Keigo Suzuki 《Advanced functional materials》2023,33(2):2209538
Striving for the sixth-generation communication technology discovery, semiconductors beyond Si with wider bandgaps as well as non-conventional metals are actively being sought to achieve high speeds whilst maintaining devices miniaturization. 2D materials may provide the potential for downsizing, but their functional advantage over existing counterparts still longs to be discovered. Along that path, surface-adsorbed or bulk-intercalated water molecules remaining after wet-chemical synthesis of 2D materials are generally seen as obstacles to high-performance achievement. Herein, the control of such water within the interlayers of solution-processed metallic 2D titanium carbide (MXene) by vacuum annealing duration is demonstrated. Moreover, the impact of water removal on work function (WF) and functional terminations is unveiled for the first time. Furthermore, the usefulness of such water for controlling a novel Schottky diode in contact with an n-type oxide semiconductor, niobium-doped strontium titanate (Nb:SrTiO3) is observed. The advantage of MXene compared to conventional gold as facile processing, WF tunability, and lower turn-on voltage in the Schottky anode application is highlighted. This fundamental study shows the way for a novel Schottky diode preparation in atmospheric conditions and provides implications for further research directions aiming at commercialization. 相似文献
18.
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
19.
肖特基半导体器件的模型及其应用 总被引:1,自引:0,他引:1
从工程实际出发,分别建立了肖特基势垒二极管(SBD)二态模型和肖特基钳位三极管(SCT)四态模型的电路模型,分析并研究了这两个典型的应用电路。 相似文献
20.