Microstructural Analysis of Ti/Ni Bilayer Ohmic Contacts on 4H-SiC Layers

Materials Science Forum ◽

10.4028/www.scientific.net/msf.963.494 ◽

2019 ◽

Vol 963 ◽

pp. 494-497

Author(s):

Vinoth Kumar Sundaramoorthy ◽

Lukas Kranz ◽

Giovanni Alfieri

Keyword(s):

Structural Analysis ◽

Diffraction Pattern ◽

Ohmic Contacts ◽

Microstructural Analysis ◽

Carbon Segregation ◽

Film Interface

The micro-structural analysis of Ti/Ni bilayer as Ohmic contacts to n-type 4H-SiC is reported. There was no carbon segregation at the interface between the NiSi layer and the 4H-SiC layer for Ti/Ni contacts, unlike pure Ni contacts. The diffraction pattern image shows the presence of the cubic NiSi film which grows on the SiC surface. The film interface with the SiC was uniform and more planar. An optimized contact in terms of contact morphology was achieved using a bilayer contact Ti/Ni (20/100nm) annealed at 1100 °C for 5 minutes in vacuum.

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Structural analysis of Ni3Si2by EDT and dynamical refinement

Acta Crystallographica Section A Foundations and Advances ◽

10.1107/s2053273314096272 ◽

2014 ◽

Vol 70 (a1) ◽

pp. C372-C372

Author(s):

Cinthia Corrêa ◽

Mariana Klementová ◽

Lukáš Palatinus

Keyword(s):

Structural Analysis ◽

Electron Diffraction ◽

Ohmic Contacts ◽

Low Cost ◽

Complementary Metal Oxide Semiconductor ◽

Diffraction Theory ◽

Oxide Semiconductor ◽

Metal Silicides ◽

Precession Electron Diffraction ◽

Low Toxicity

Transition metal silicides are known for properties such as low resistivity, high melting point, low cost and low toxicity, which are of great interest for applications in current silicon nanotechnology such as nano-complementary metal-oxide semiconductor (CMOS) devices, photovoltaics and ohmic contacts. In all these technologies the materials are used on nanoscale. To gain better insight into their properties, it is necessary to be able to determine the structure of the nanoparticles of these materials. Electron diffraction tomography combined with the precession electron diffraction (PED) are ideal techniques for structural analysis of nanocrystals. In this work Ni3Si2 nanowires with diameter of 25 nm were analyzed by EDT both with and without PED. The structure was refined using the kinematical and dynamical diffraction theory. The results show that the best results can be obtained of EDT and PED.

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Microstructure and Temperature Dependent Electrical Characteristics of Ohmic Contacts to AlGaN/GaN Heterostructures

Materials Science Forum ◽

10.4028/www.scientific.net/msf.821-823.999 ◽

2015 ◽

Vol 821-823 ◽

pp. 999-1002

Author(s):

Giuseppe Greco ◽

Ferdinando Iucolano ◽

Fabrizio Roccaforte

Keyword(s):

Ohmic Contacts ◽

Microstructural Analysis ◽

Specific Contact Resistance ◽

Interfacial Region ◽

Temperature Dependent ◽

Scientific Debate ◽

Specific Contact ◽

Thermionic Field Emission ◽

High Frequency Devices ◽

Dimensional Electron Gas

AlGaN/GaN heterostructures are important materials for the fabrication of high power and high frequency devices. However, the mechanisms of Ohmic contacts formation on these systems are continuously under scientific debate. In this paper, a structural and electrical investigation of Ti/Al/Ni/Au Ohmic contacts to AlGaN/GaN heterostructures is reported. In particular, the behavior of Ti/Al/Ni/Au multilayers was monitored at different annealing temperatures. The contacts became Ohmic after annealing at 750°C and showed a decreasing temperature behavior of the specific contact resistanceRC, described by a thermionic field emission mechanism. On the other hand, annealing at 850°C led to a further reduction ofRC, with a slightly increasing dependence ofRCon the measurement temperature (here regarded as a “metal-like” behavior). The microstructural analysis of the interfacial region allowed to explain the results with the formation of metallic intrusions contacting directly the two dimensional electron gas.

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Microstructural analysis of NiInGe ohmic contacts for n-type GaAs

Journal of Electronic Materials ◽

10.1007/s11664-002-0176-6 ◽

2002 ◽

Vol 31 (1) ◽

pp. 76-81 ◽

Cited By ~ 6

Author(s):

Yukito Tsunoda ◽

Masanori Murakami

Keyword(s):

Ohmic Contacts ◽

Microstructural Analysis

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Structural analysis of interfacial layers in Ti/Ta/Al ohmic contacts to n-AlGaN

Journal of Applied Physics ◽

10.1063/1.1323517 ◽

2000 ◽

Vol 88 (11) ◽

pp. 6364-6368 ◽

Cited By ~ 12

Author(s):

S.-H. Lim ◽

W. Swider ◽

J. Washburn ◽

Z. Liliental-Weber

Keyword(s):

Structural Analysis ◽

Ohmic Contacts ◽

Interfacial Layers

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Structural analysis of Au–Ni–Ge and Au–Ag–Ge alloyed ohmic contacts on modulation‐doped AlGaAs–GaAs heterostructures

Journal of Applied Physics ◽

10.1063/1.337413 ◽

1986 ◽

Vol 60 (2) ◽

pp. 677-680 ◽

Cited By ~ 18

Author(s):

T. K. Higman ◽

M. A. Emanuel ◽

J. J. Coleman ◽

S. J. Jeng ◽

C. M. Wayman

Keyword(s):

Structural Analysis ◽

Ohmic Contacts

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Fabrication and Characterization of Ohmic Contacts to 3C-SiC Layers Grown on Silicon

Materials Science Forum ◽

10.4028/www.scientific.net/msf.963.485 ◽

2019 ◽

Vol 963 ◽

pp. 485-489

Author(s):

Monia Spera ◽

Giuseppe Greco ◽

Raffaella Lo Nigro ◽

Salvatore di Franco ◽

Domenico Corso ◽

...

Keyword(s):

Structural Analysis ◽

Ohmic Contacts ◽

Specific Contact Resistance ◽

Silicon Substrates ◽

X Ray Diffraction ◽

X Ray ◽

Specific Contact ◽

Fabrication And Characterization ◽

P Type

This paper reports on the formation and characterization of Ohmic contacts to n-type and p-type type 3C-SiC layers grown on silicon substrates. In particular, Ohmic contact behavior was obtained either using Ni or Ti/Al/Ni layers annealed at 950°C. The values of the specific contact resistance ρc estimated by means of circular TLM (C-TLM) structures varied in the range ~ 10-3-10-5 Ωcm2, depending on the doping level of the 3C-SiC layer. A structural analysis performed by X-Ray Diffraction (XRD) allowed to identify the main phases formed upon annealing, i.e., Ni2Si and Al3Ni2. The morphology of the reacted contacts depended on that of the underlying substrate. The results can be useful for the development of a variety of devices on the cubic 3C-SiC polytype.

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Nanostructure to thermal property relationship of resorcinol formaldehyde aerogels using the fractal technique

Nanoscale ◽

10.1039/c8nr01375f ◽

2018 ◽

Vol 10 (22) ◽

pp. 10564-10575 ◽

Cited By ~ 17

Author(s):

Mohammed Alshrah ◽

Lun Howe Mark ◽

Chongxiang Zhao ◽

Hani E. Naguib ◽

Chul B. Park

Keyword(s):

Structural Analysis ◽

Thermal Property ◽

Diffraction Pattern ◽

X Ray Diffraction ◽

Resorcinol Formaldehyde ◽

X Ray ◽

Property Relationship ◽

Relationship Of

Structural analysis of the X-ray diffraction pattern of microstructures using the fractal technique.

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Time constraints and fault kinematic evolution of the Periadriatic Fault System along the Meran-Mauls segment (N Italy)

10.5194/egusphere-egu21-2162 ◽

2021 ◽

Author(s):

Stefano Zanchetta ◽

Chiara Montemagni ◽

Claudia Mascandola ◽

Andrea Zanchi

Keyword(s):

Structural Analysis ◽

Seismic Activity ◽

Microstructural Analysis ◽

Shear Zones ◽

Fault System ◽

Time Interval ◽

Brittle Deformation ◽

The North ◽

Kinematic Evolution ◽

Deformation Regime

The Periadriatic Fault System (PFS) is one of the most important tectonic element in the Alps, separating the Europe-verging collisional wedge from the S-verging Southern Alps. The PFS developed in a dextral transpressional regime during the Cenozoic, following the Adria-Europe collision. The area between the Passeier and the Eisack rivers (Meran, NE Italy) is a key area for the understanding of the interactions among the PFS, the Giudicarie Fault and the fault network here active in the middle to late Cenozoic. Here the elsewhere E-W trending PFS rotates to a NE-SW trend, impliying significant changes in the fault kinematics and evolution.The NE-SW strand of the PFS, known as the Meran-Mauls fault, is connected to the North Giudicarie Fault to the west and to the Pustertal segment of the PFS to the east. A general evolution from the ductile to brittle deformation regime has been recognized on the base of field-based structural analysis and microstructural analysis of fault rocks. Pseudotachylytes occur all along the fault zone, testifying to the seismic activity of the Meran-Mauls fault. 40Ar-39Ar dating of pseudotachylytes provided ages in the 32-22 Ma time interval, indicating that the PFS experienced a prolonged seismic activity during middle Cenozoic times. Several pseudotachylytes veins show a re-activation as cm-thick ductile shear zones, indicating that the plastic-brittle transition was not sharp in time.Combining the structural analysis of the PFS with other adjacent faults connected in space and time (Passeier fault, Faltleis fault, Val Nova fault and other minor faults) we reconstructed a marked reverse dip-slip kinematics of the Meran-Mauls Fault during a progressive transition across the plastic-brittle regime, followed in time by a dextral transpression. Paleostress reconstructions performed on these faults populations indicate a progressive switch of the main direction of compression from NW-SE to N-S. This switch likely occurred when the Meran-Mauls segment of the PFS definitively passed to a brittle deformation regime.&#160;

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