Reaction of Amorphous Minb Films with Crystalline Metal Overlayers

1984 ◽  
Vol 37 ◽  
Author(s):  
E. A. Dobisz ◽  
B. L. Doyle ◽  
J. H. Perepezko ◽  
J. D. Wiley ◽  
P. S. Peercy
Keyword(s):  
Metal Film ◽  
Rutherford Backscattering Spectrometry ◽  
Amorphous Film ◽  
Depth Resolution ◽  
Rutherford Backscattering ◽  
Amorphous Films ◽  
The Stability ◽  
Metal Overlayers ◽  
Crystalline Metal ◽  
High Depth

AbstractIn many cases the stability of amorphous films is influenced by interaction with metallic crystalline overlayers. Such interactions between Au, Ni, Nb and Ta overlayers and a-(Ni-Nb) films are reported. During interdiffusion Au overlayers reacted with a-(Ni-Nb) to form two different adjacent crystalline layers. In order to study the influence of relaxation of the amorphous film on overlayer reaction several a-(Ni-Nb) samples were pre-annealed prior to Au deposition. High depth resolution Rutherford Backscattering Spectrometry (RBS) demonstrates that preannealing lowers the diffusion poefficient of Au in a-(Ni-Nb) at 4500C from 7.5×10−22 m2/s to 8.7×10−23 m22/s. During interdiffusion Ta was discovered to be substantially more inert than Au. For example, negligible interdiffusion between Ta and a-(Ni-Nb) at 505°C after 25 hours implies a diffusivity of less than 5×10−24 m2/s. These observations allow assessment of some of the requirements for increasing the stability of crystalline-amorphous metal film layered structures.

The Stability to Ageing of Pd/Zn and Pt-Based Ohmic Contacts to p-InGaAs/InP

1998 ◽  
Vol 514 ◽  
Author(s):  
P. W. Leech ◽  
G. K. Reeves ◽  
P. Ressel
Keyword(s):  
Contact Resistance ◽  
Barrier Layer ◽  
Ohmic Contacts ◽  
Rutherford Backscattering Spectrometry ◽  
Rutherford Backscattering ◽  
Contact System ◽  
Specific Contact Resistance ◽  
Barrier Layers ◽  
Specific Contact ◽  
The Stability

ABSTRACTPd/Zn/Au contacts to p-In0.53Ga0.47As/InP with various barrier layers (Pd, Pt or LaB,) to the indiffusion of Au have been examined by Rutherford Backscattering Spectrometry (RBS). For the metallisations with a barrier layer of Pd, the ageing of the contacts at 400°C for 20 h produced a widespread indiffusion of Au. In comparison, the incorporation of a layer of Pt or amorphous LaB6 prevented an indiffusion of Au and significantly reduced any outdiffusion of the semiconductor elements. The presence of the barrier layer of Pt or LaB6 produced little or no detrimental increase in specific contact resistance, ρc, for this contact system. Values of ρc in the range 8–10 × 10−6 Ω cm2 were obtained for all of the contacts based on Pd/Zn/Au after annealing at 500°C. A comparison has been made with the characteristics of Pt/Ti/Pt/Au contacts to p-In0.53Ga0.47As/ InP which were shown as stable against the indiffusion of Au.

Optimizing the Depth Resolution of Rutherford Backscattering Through Modeling of Noise Sources

1986 ◽  
Vol 69 ◽  
Author(s):  
John R. Abelson ◽  
T. W. Sigmon
Keyword(s):  
Rutherford Backscattering Spectrometry ◽  
Grazing Angle ◽  
Depth Resolution ◽  
Normal Incidence ◽  
Low Noise ◽  
Forward Scattering ◽  
Rutherford Backscattering ◽  
Acceptance Angle ◽  
Noise Sources ◽  
Near Surface

AbstractGrazing angle configurations improve the depth resolution of Rutherford Backscattering Spectrometry (RBS) because the path length of scattered particles is geometrically increased. But in the limit of very grazing angles the resolution degrades due to the finite detector acceptance angle and low angle forward scattering of the beam, considerations which are not present in near-normal incidence geometries. The forward scattering, for example, worsens the depth resolution approximately as the square of the depth, rather than the familiar square root dependence of energy straggling. We present a simple computational scheme which predicts the depth resolution in any target as a function of scattering depth, beam energy, and the grazing angle. The calculations are simpler than previous studies because we use analytic expressions in place of numerical inputs without loss of accuracy. The results lead directly to an optimum depth resolution. We find good agreement between the predicted resolution and measurements on thin silicon dioxide and amorphous silicon films. Finally, we calculate the resolution expected with the use of ion beams heavier than He+, and find improved near surface depth resolution if a low noise detector is used.

Early Stages Of Reaction Between Amorphous Ni-Nb And Crystalline Au Films

1985 ◽  
Vol 54 ◽  
Author(s):  
E. A. Dobisz ◽  
H. G. Craighead ◽  
J. H. Perepezko ◽  
J. D. Wiley ◽  
B. L. Doyle ◽  
...  
Keyword(s):  
Thin Film ◽  
Cross Section ◽  
Ternary Compound ◽  
Growth Kinetics ◽  
Depth Resolution ◽  
Compound Layer ◽  
Rutherford Backscattering ◽  
Early Stages ◽  
Kinetics Of ◽  
High Depth

ABSTRACTThin film interactions between a-(Ni-Nb) and polycrystalline Au over-layers have been studied with high depth resolution (≤1.7nm) Rutherford backscattering (RBS) and TEM to obtain information on the early stages of reaction at the interface. The RBS spectra from Au indicated that the interdiffused samples consisted of two layers: an Au-Nb binary layer on the surface and a ternary Au-Ni-Nb compound layer beneath the binary layer. The growth kinetics of the ternary compound layer differed in samples which had been relaxed prior to Au deposition from the kinetics for unrelaxed samples. Furthermore, cross section TEM micrographs showed that relaxed and unrelaxed samples exhibit different microstructures after the early stages, of annealing. We interpret this result to indicate that the reaction stages in relaxed samples are not as advanced as those in the unrelaxed samples.

scholarly journals Analytical Possibilities of Rutherford Backscattering Spectrometry and Elastic Recoil Detection Analysis Methods

2016 ◽  
Vol 26 (1) ◽  
pp. 83 ◽  
Author(s):  
Vu Duc Phu ◽  
Le Hong Khiem ◽  
A. P. Kobzev ◽  
M. Kulik
Keyword(s):  
Rutherford Backscattering Spectrometry ◽  
Depth Resolution ◽  
Rutherford Backscattering ◽  
Elastic Recoil ◽  
Elastic Recoil Detection Analysis ◽  
Near Surface ◽  
Elastic Recoil Detection ◽  
Depth Profiles ◽  
Detection Analysis ◽  
Three Samples

This paper presents the results of an experimental study of three samples containing various elements in the near-surface layers. The depth profiles of all the elements of different atomic masses from hydrogen to silver were investigated by Rutherford Backscattering Spectrometry (RBS) and Elastic Recoil Detection Analysis (ERDA). The experiments were performed by using the low-energy (about 2 MeV) 4He+ ion beams. The obtained results demonstrate the possibility of the RBS and ERDA methods in the investigation of depth profiles of any mass element with an atomic concentration of about 0.01 at.% and a depth resolution close to 10 nm.

Strain and Compositional Analysis of InGaN/GaN Layers

2000 ◽  
Vol 639 ◽  
Author(s):  
Sérgio Pereira ◽  
Maria. R. Correia ◽  
Estela Pereira ◽  
C. Trager-Cowan ◽  
F. Sweeney ◽  
...  
Keyword(s):  
Driving Force ◽  
Rutherford Backscattering Spectrometry ◽  
Compositional Analysis ◽  
Depth Resolution ◽  
Indium Content ◽  
Rutherford Backscattering ◽  
X Ray Diffraction ◽  
Strained Layers ◽  
X Ray ◽  
Strain Components

ABSTRACTWe investigate strain and composition of epitaxial single layers of wurtzite InxGa1−xN (0<x<0.25) grown by MOCVD on top of GaN/Al203 substrates. It is shown that significant inaccuracies may arise in composition assessments if strain in InxGa1−xN/GaN heterostructures is not properly taken into account. Rutherford backscattering spectrometry (RBS) measures composition, free from the effects of strain and with depth resolution. Using X-ray diffraction (XRD) we measure both a- and c- parameters of the strained wurtzite films. By measuring both lattice parameters and solving Hooke's equation, a good estimation for composition can be obtained from XRD data. The agreement between RBS and XRD data for composition allows reliable values for perpendicular (εzz) and parallel strain components ( (εxx) to be determined. RBS and depth resolved cathodoluminescence (CL) measurements further indicate that the indium content is not uniform over depth in some samples. This effect occurs for the most strained layers, suggesting that strain is the driving force for compositional pulling.

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