Nanodot Formation in Thermally Annealed UHV-RTCVD Grown Si1-XGeX Epitaxial Layers on Silicon for Photovoltaics

2011 ◽  
Vol 1322 ◽  
Author(s):  
Abdennaceur Karoui ◽  
Anita S. Ethiraj
Keyword(s):  
Low Cost ◽  
Misfit Dislocations ◽  
Bandgap Engineering ◽  
Small Shift ◽  
X Ray ◽  
Force Microscopy ◽  
Surface And Interface ◽  
Strain Pattern ◽  
Atomic Force ◽  
Low Thermal Budget

ABSTRACTThe surface and interface of SiGe layers on Si were found to incur drastic changes during layer rapid growth and post-growth rapid annealing. As deposited and thermal annealed samples were characterized using Energy dispersive X-ray Analysis (EDX) enhanced by Monte Carlo simulation for precise evaluation of Ge concentration. X-ray Diffraction (XRD) data exhibited a small shift of the SiGe (400) peak towards low 2θ values, which was attributed, primarily, to change in the Ge concentration. Confocal Raman Spectroscopy of samples showed regions of high and low strain that resulted from fluctuations in Ge concentrations. Nano- and submicronpyramidal features at the surface of Si1-xGex layers (x=17% and 28%) were revealed by Atomic Force Microscopy (AFM) and SEM. Additionally, pyramidal nanodots were revealed for [Ge]=17% samples and high density nanostructure for 28% appeared along the crosshatch strain pattern induced by misfit dislocations, when annealed at 700°C and 900°C, respectively. The observed Ge-rich nano-features, which were obtained with low thermal budget low cost techniques, are expected to be useful for bandgap engineering and third generation solar cells.

Hard High Density Carbon Thin Films for X-Ray Multilayer Optics

1994 ◽  
Vol 349 ◽  
Author(s):  
Joseph Pedulla ◽  
Axel Bartos ◽  
Richard D. Deslattes
Keyword(s):  
Ion Beam ◽  
High Hardness ◽  
Carbon Films ◽  
High Electron ◽  
Optical Elements ◽  
X Ray ◽  
Force Microscopy ◽  
Surface And Interface ◽  
Atomic Force ◽  
High Uniformity

ABSTRACTDual ion beam assisted deposition (DIBAD) techniques are known to produce high quality diamond-like carbon films. The reported extreme hardness and high thermal conductivity characteristics of these films have stimulated our investigation of their use as one component of multilayer x-ray optical elements. Non-crystalline carbon films were produced and were characterized by means of highly collimated x-ray refiectometry (λ = 0.154 nn), atomic force microscopy, and IR Raman spectroscopy techniques. They exhibit extreme smoothness at the surface and interface, near diamond density, high hardness, and high uniformity over areas of 0.58 x 10-4 m2. Multilayers have been constructed of this non-crystalline carbon interposed with high electron density materials that have exhibited very good x-ray and EUV optical characteristics at λ = 0.154 nm and at λ = 4.0 – 8.0 nm.

Improvement of surface and interface roughness estimation on X-ray reflectivity

2014 ◽  
Vol 29 (3) ◽  
pp. 265-268 ◽  
Author(s):  
Y. Fujii
Keyword(s):  
Diffuse Scattering ◽  
Interface Roughness ◽  
Careful Study ◽  
Angle Of Incidence ◽  
Interference Effects ◽  
X Ray ◽  
Force Microscopy ◽  
Surface And Interface ◽  
Effective Roughness ◽  
Atomic Force

In the conventional X-ray reflectivity (XRR) analysis, the reflectivity is calculated based on the Parratt formalism, incorporating the effect of the interface roughness according to Nevot and Croce. However, the results of calculations of the XRR have shown strange outcomes, where interference effects increase at a rough surface because of a lack of consideration of diffuse scattering within the Parratt formalism. Therefore, we have developed a new improved formalism in which the effects of the surface and interface roughness are included correctly. In this study, for deriving a more accurate formalism of XRR, we tried to compare the measurements of surface roughness of the same sample by atomic force microscopy (AFM) and XRR. It is found that the AFM result could not be completely reproduced even with the improved XRR formalism. By careful study of the AFM results, we determined the need for an additional effective roughness term within the XRR simulation that depends on the angle of incidence of the beam.

Low Thermal Budget NiSi Films on SiGe Alloys

2002 ◽  
Vol 745 ◽  
Author(s):  
S. K. Ray ◽  
T. N. Adam ◽  
G. S. Kar ◽  
C. P. Swann ◽  
J. Kolodzey
Keyword(s):  
Photoelectron Spectroscopy ◽  
Thermal Budget ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
Higher Temperature ◽  
Ultra Shallow Junctions ◽  
The Stability ◽  
Xps Study ◽  
Low Thermal Budget

ABSTRACTNickel silicides were formed on Si (100) substrates and CVD grown Si0.9Ge0.1/Si layers by low thermal budget annealing of evaporated Ni films to evaluate their utility for ultra shallow junctions. The phase formation and microstructure of silicides formed using conventional furnace and rapid thermal annealing were studied by x-ray diffraction, Rutherford backscattering (RBS), x-ray photoelectron spectroscopy (XPS) and atomic force microscopy. RBS simulations and XPS study revealed the formation of a ternary nickel germanosilicide phase for the SiGe alloy. The incorporation of Ge resulted in a higher temperature window for the stability of low-resistive monosilicide phase. Electrical properties of the grown silicides were characterized by four-probe resistivity and contact resistance measurements.

Atomic force microscopy and X-ray diffraction study of surface and interface roughness in Nb/Cu multilayers

1996 ◽  
Vol 156 (1-3) ◽  
pp. 109-110 ◽  
Author(s):  
K. Temst ◽  
M.J. Van Bael ◽  
D.G. de Groot ◽  
N.J. Koeman ◽  
R.P. Griessen ◽  
...  
Keyword(s):  
Atomic Force Microscopy ◽  
Diffraction Study ◽  
Interface Roughness ◽  
X Ray Diffraction ◽  
X Ray ◽  
Force Microscopy ◽  
Surface And Interface ◽  
Atomic Force

scholarly journals Electroplating of Semiconductor Materials for Applications in Large Area Electronics: A Review

Coatings ◽  
2018 ◽  
Vol 8 (8) ◽  
pp. 262 ◽  
Author(s):  
Ayotunde Adigun Ojo ◽  
Imyhamy Mudiy Dharmadasa
Keyword(s):  
Low Cost ◽  
Photoelectrochemical Cell ◽  
X Ray Diffraction ◽  
Large Area ◽  
X Ray ◽  
Force Microscopy ◽  
Treatment Processes ◽  
Atomic Force ◽  
Optical And Electronic Properties ◽  
Device Applications

The attributes of electroplating as a low-cost, simple, scalable, and manufacturable semiconductor deposition technique for the fabrication of large-area and nanotechnology-based device applications are discussed. These strengths of electrodeposition are buttressed experimentally using techniques such as X-ray diffraction, ultraviolet-visible spectroscopy, scanning electron microscopy, atomic force microscopy, energy-dispersive X-ray spectroscopy, and photoelectrochemical cell studies. Based on the results of structural, morphological, compositional, optical, and electronic properties evaluated, it is evident that electroplating possesses the capabilities of producing high-quality semiconductors usable for producing excellent devices. In this paper we will describe the progress of electroplating techniques mainly for the deposition of semiconductor thin film materials and their treatment processes, and fabrication of solar cells.

Atomic Force Microscopy and X-Ray Photoelectron Spectroscopy Study on the Surface and Interface States of Liq and ITO Films

2010 ◽  
Vol 152-153 ◽  
pp. 566-571
Author(s):  
Jian Feng Li ◽  
Qing Song ◽  
Wei Bing Shi ◽  
Fu Jia Zhang
Keyword(s):  
Atomic Force Microscopy ◽  
Indium Tin Oxide ◽  
Photoelectron Spectroscopy ◽  
Interface States ◽  
Xps Spectra ◽  
X Ray ◽  
Force Microscopy ◽  
Surface And Interface ◽  
Atomic Force ◽  
Blue Electroluminescent Material

An understanding of the surface and interface states of the organic material and the underlying andoe material is meaningful for organic light-emitting devices (OLEDs). The 8-Hydroxyquinolinolatolithium (Liq) was deposited on indium-tin-oxide (ITO) coated glass by traditional vacuum evaporation.The thickness of Liq is about 120nm. The morphology, surface and interface electron states of the Liq and the underlying ITO have been investigated with the utilization of the atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS) technology. AFM observation indicated that Liq grows in the shape of an asymmetrically-distributed island, with each island resembling a round hillock and different size. The Liq film is not very uniform and teemed with many pinholes and cracks.The analysis on XPS spectra of the surface of the Liq/ITO samples shows that, the core-levels of Li1s, C1s, N1s, O1s, In3d5/2, and Sn3d5/2, spectra slightly shift towards lower binding energy with the increase of the sputtering time, which may be caused by the effect of oxygen, indium and tin in ITO diffusing into Liq layer and the argon ions beam with energy. Coordination bond between Li atoms and N atoms does not exist in Liq, which is the main reason why Liq is the blue electroluminescent material. The C atoms mainly bond to C, N and O atoms, forming C-C, C-N=C and C-O bonds, respectively. And there is a speculation of the existence of contaminated C atoms in the surface of ITO, while the O atoms basically originate from quinolate rings and the absorption of O2 and H2O. At the interface N and O, In and Sn interact to some extent, which probably affects the emitting colour of Liq based OLEDs. The analysis of surface of In3d and Sn3d spectrum by XPS provides additional evidence of the existence of cracks and pinholes in Liq layer, leading to much absorption of air molecules.

The Surface and Interface Microstructure of Epitaxial Pr0.7Sr0.3MnO3/La0.5Ca0.5MnO3 Bilayer Structure

2013 ◽  
Vol 372 ◽  
pp. 75-79
Author(s):  
Haiou Wang ◽  
Hao Liu ◽  
Meng Xiong Cao ◽  
Wei Shi Tan ◽  
Ping Dai ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Mass Density ◽  
Bilayer Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Force Microscopy ◽  
Surface And Interface ◽  
Lcmo Film ◽  
Atomic Force ◽  
Disordered Layer

Epitaxial bilayer structure consisting of ferromagnetic (FM) metallic Pr0.7Sr0.3MnO3 (PSMO) and antiferromagnetic (AFM) insulator La0.5Ca0.5MnO3 (LCMO) was fabricated on (001)-oriented single crystal SrTiO3 (STO) substrate by pulsed laser deposition technique. We studied the surface structure and interdiffusion at interface between PSMO and LCMO by using atomic force microscope and grazing incident x-ray reflectivity (GIXRR). The perfect data fitting result of GIXRR indicated that interdiffusion at the interface of Pr0.7Sr0.3MnO3/La0.5Ca0.5MnO3 (PSMO/LCMO) could not be negligible; there was a large interdiffusion zone at the PSMO/LCMO interfaces with a thickness of about 7 nm. We found that the thickness of the top layer at air/PSMO interface was about 2.5 nm and the mass density of the top layer was about 76.53% of that of PSMO layer. The surface roughness was about 1.6 nm which was consistent with observation by atomic force microscopy. Normal X-ray diffraction (NXRD) was also employed to investigate the average structure. Except from PSMO and LCMO layer diffraction peaks, we observed another additional peak, which was developed from the large disordered layer resulting from interdiffusion at the interface of PSMO/LCMO. This implied that the variation of crystalline structure of PSMO/LCMO film occurred due to interdiffusion. Surface roughness and interdiffusion played an important role in magnetic properties of FM/AFM bilayer.

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