Some Recent Results on the 3C-SiC Structural Defects

2010 ◽  
Vol 159 ◽  
pp. 39-48 ◽  
Author(s):  
Maya Marinova ◽  
Alkyoni Mantzari ◽  
Efstathios K. Polychroniadis
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Vapour Deposition ◽  
Chemical Vapour ◽  
Layer Growth ◽  
Structural Defects ◽  
Vapour Transport ◽  
Transmission Electron ◽  
Continuous Feed ◽  
The Common

This work presents some recent results on the 3C-SiC structural defects, studied by Transmission Electron Microscopy (TEM). The samples studied were grown in several laboratories, using different methods. Commonly used methods for growth are Sublimation Epitaxy (SE), Physical Vapour Transport (PVT), Continuous Feed Physical Vapour Transport (CF-PVT), Chemical Vapour Deposition (CVD), and Liquid Phase Epitaxy (LPE). In all these methods, for both bulk and epitaxial layer growth, substrates from other polytypes are exploited like the common hexagonal polytypes 4H- and 6H-SiC or 3C-SiC seeds both in (111) and (100) orientation.

Microstructure of Thin Film Photoconductors and its Correlation with Optical and Electronic Properthss

1996 ◽  
Vol 452 ◽  
Author(s):  
U. Klement ◽  
D. Horst ◽  
F. Ernst
Keyword(s):  
Thin Film ◽  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Vapour Deposition ◽  
Chemical Vapour ◽  
Hydrogenated Silicon ◽  
Amorphous Hydrogenated Silicon ◽  
Transmission Electron ◽  
Electronic Eye

AbstractThe objective of this work is to find a material to replace amorphous hydrogenated silicon used as photosensitive part in the “retina” of an “electronic eye”. For that reason, ZnS, ZnSe, CdS and CdSe were chosen for investigations. Thin films, prepared by chemical vapour deposition, were characterized by transmission electron microscopy. The observed microstructures were correlated with the optoelectronic properties of these materials. CdSe was found to be the most promising material for our application. Hence, the influence of a dielectric interlayer and the effects of additional annealing treatments were analyzed for CdSe and will be discussed with respect to the optimization of the material.

On the Twin Boundary Propagation in (111) 3C-SiC Layers

2012 ◽  
Vol 717-720 ◽  
pp. 419-422 ◽  
Author(s):  
Maya Marinova ◽  
Ariadne Andreadou ◽  
Alkyoni Mantzari ◽  
Efstathios K. Polychroniadis
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
High Resolution ◽  
Twin Boundary ◽  
Chemical Vapour Deposition ◽  
Vapour Deposition ◽  
Chemical Vapour ◽  
Vapor Liquid Solid ◽  
Stages Of Growth ◽  
Transmission Electron

The present study reports on the propagation of twin boundaries in (111) 3C-SiC by means of conventional (CTEM) and high resolution transmission electron microscopy (HRTEM). The investigated 3C-SiC layers were homoepitaxially grown by Chemical Vapour Deposition (CVD) on layers previously grown by Vapor Liquid Solid (VLS) mechanism on 6H-SiC substrates. At the initial stages of growth the usual twin boundary that occurs is an incoherent {-211} Σ3 one. It transforms to more energetically favorable cases by several ways: (i) The initial {-211} boundary turns 90º, to a fully coherent (111) interface, forming microtwins; (ii) A step-like interface occurs with facets along the (111) and the {-211} planes; (iii) It transforms in a fourfold twin complex propagating to the surface.

Dechannealing Study of Nanocrystalline Si:H Layers Produced by High Dose Hydrogen Irradiation of Silicon Crystals

1998 ◽  
Vol 536 ◽  
Author(s):  
V. P. Popov ◽  
A. K. Gutakovsky ◽  
I. V. Antonova ◽  
K. S. Zhuravlev ◽  
E. V. Spesivtsev ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Rutherford Backscattering Spectrometry ◽  
Nanocrystalline Structure ◽  
Structural Defects ◽  
High Dose ◽  
Silicon Crystals ◽  
Strong Energy ◽  
Transmission Electron ◽  
Hydrogen Implantation

AbstractA study of Si:H layers formed by high dose hydrogen implantation (up to 3x107cm-2) using pulsed beams with mean currents up 40 mA/cm2 was carried out in the present work. The Rutherford backscattering spectrometry (RBS), channeling of He ions, and transmission electron microscopy (TEM) were used to study the implanted silicon, and to identify the structural defects (a-Si islands and nanocrystallites). Implantation regimes used in this work lead to creation of the layers, which contain hydrogen concentrations higher than 15 at.% as well as the high defect concentrations. As a result, the nano- and microcavities that are created in the silicon fill with hydrogen. Annealing of this silicon removes the radiation defects and leads to a nanocrystalline structure of implanted layer. A strong energy dependence of dechanneling, connected with formation of quasi nanocrystallites, which have mutual small angle disorientation (<1.50), was found after moderate annealing in the range 200-500°C. The nanocrystalline regions are in the range of 2-4 nm were estimated on the basis of the suggested dechanneling model and transmission electron microscopy (TEM) measurements. Correlation between spectroscopic ellipsometry, visible photoluminescence, and sizes of nanocrystallites in hydrogenated nc-Si:H is observed.

Synthesis and Photoluminescence Properties of Novel SnO2 Zigzag Nanoribbons

2010 ◽  
Vol 97-101 ◽  
pp. 4213-4216
Author(s):  
Jian Xiong Liu ◽  
Zheng Yu Wu ◽  
Guo Wen Meng ◽  
Zhao Lin Zhan
Keyword(s):  
Electron Microscopy ◽  
Room Temperature ◽  
Vapour Deposition ◽  
Chemical Vapour ◽  
Photoluminescence Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Selected Area Electron Diffraction ◽  
Transmission Electron ◽  
Ceramic Boat

Novel single-crystalline SnO2 zigzag nanoribbons have been successfully synthesized by chemical vapour deposition. Sn powder in a ceramic boat covered with Si plates was heated at 1100°C in a flowing argon atmosphere to get deposits on a Si wafers. The main part of deposits is SnO2 zigzag nanoribbons. They were characterized by means of X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM) and selected-area electron diffraction (SAED). SEM observations reveal that the SnO2 zigzag nanoribbons are almost uniform, with lengths near to several hundred micrometers and have a good periodically tuned microstructure as the same zigzag angle and growth directions. Possible growth mechanism of these zigzag nanoribbons was discussed. A room temperature PL spectrum of the zigzag nanoribbons shows three peaks at 373nm, 421nm and 477nm.The novel zigzag microstructures will provide a new candidate for potential application.

Citrate Stabilized Silver Nanoparticles

2011 ◽  
Vol 3 (3) ◽  
pp. 15-28 ◽  
Author(s):  
Nabraj Bhattarai ◽  
Subarna Khanal ◽  
Pushpa Raj Pudasaini ◽  
Shanna Pahl ◽  
Dulce Romero-Urbina
Keyword(s):  
Crystal Structure ◽  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Silver Nanoparticles ◽  
Zeta Potential ◽  
Colloidal Solution ◽  
Measurement Techniques ◽  
Structural Defects ◽  
Potential Measurement ◽  
Transmission Electron

Citrate stabilized silver (Ag) colloidal solution were synthesized and characterized for crystallographic and surface properties by using transmission electron microscopy (TEM) and zeta potential measurement techniques. TEM investigation depicted the size of Ago ranges from 5 to 50 nm with smaller particles having single crystal structure while larger particles with structural defects (such as multiply twinned, high coalescence and Moire patterns). ?-potential measurement confirms the presence of Ag+ in nAg stock solution. The shift in ?-potential measurement by +25.1 mV in the filtered solution suggests the presence of Ag+ in Ago nanoparticles.

Formation of Excess Donors During High-Dose 74Ge+ Ion Implantation

1994 ◽  
Vol 354 ◽  
Author(s):  
Z. Xia ◽  
E. Ristolainen ◽  
R. Elliman ◽  
H. Ronkainen ◽  
S. Eränen ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Structural Defects ◽  
High Dose ◽  
Donor Concentration ◽  
Materials Analysis ◽  
Si Substrates ◽  
Transmission Electron ◽  
Activation Annealing ◽  
Secondary Ion

AbstractRecently observations that high-dose Ge implantations into Si substrates caused the n-type carrier concentration to increase were attributed to residual structural defects after activation annealing [7,12]. However, co-implantation of an n-type impurity is another possibility. The origin of this excess donor concentration has been studied in this work. The possibilities of residual defects versus implantation of impurities have been investigated using two different implanters and materials analysis. Comparison of data from different implanters showed that the concentration of excess donors was sensitive to the implanter configuration. Furthermore, transmission electron microscopy (TEM), Rutherford backscattering channeling (RBS-C), and spreading resistance profiling (SRP) data showed that the excess donor effect was related to impurities rather than residual defects. Secondary-ion mass spectroscopy (SIMS) and SRP measurements confirmed that impurities such as 75As ions were present after implants. This impurity easily explains the excess donor concentration when 75Ge implants are performed into silicon wafers doped with phosphorous.

Structural Characterization of CF-PVT Grown Bulk 3C-SiC

2008 ◽  
Vol 600-603 ◽  
pp. 67-70 ◽  
Author(s):  
Alkyoni Mantzari ◽  
Frédéric Mercier ◽  
Maher Soueidan ◽  
Didier Chaussende ◽  
Gabriel Ferro ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Structural Properties ◽  
Structural Characterization ◽  
Stacking Faults ◽  
Vapor Transport ◽  
Physical Vapor Transport ◽  
Transmission Electron ◽  
Continuous Feed

The aim of the present work is to study the structural properties of 3C-SiC which is grown on (0001) 6H-SiC and on (100) 3C-SiC (Hoya) seeds using the Continuous Feed Physical Vapor Transport (CF-PVT) method. Transmission Electron Microscopy (TEM) observations confirm that the overgrown layer is of the 3C-SiC polytype. In the case of the 6H-SiC substrate, microtwins (MTs), stacking faults (SFs) and dislocations (D) are observed at the substrate-overgrown interface with most of the dislocations annihilating within the first few µm from the interface. In the case of 3C-SiC crystals grown on 3C seeds, repeated SFs are formed locally and also coherent (111) twins of 3C-SiC are frequently observed near the surface. The SF density is reduced at the uppermost part of the grown material.

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