TEM and LTPL Investigations of 3C-SiC Layers Grown by LPE on (100) and (111) 3C-SiC Seeds

2010 ◽  
Vol 645-648 ◽  
pp. 383-386 ◽  
Author(s):  
Maya Marinova ◽  
Georgios Zoulis ◽  
Teddy Robert ◽  
Frédéric Mercier ◽  
Alkyoni Mantzari ◽  
...  
Keyword(s):  
Liquid Phase ◽  
Liquid Phase Epitaxy ◽  
Transport Process ◽  
Defect Density ◽  
Stacking Faults ◽  
Optical Investigation ◽  
Vapour Transport ◽  
Long Period ◽  
Continuous Feed ◽  
Sic Wafer

In the present work the defects appearing in layers grown by liquid phase epitaxy on different substrates are compared. The used seeds were (i) 3C-SiC with (111) orientation, grown heteroepitaxially on (0001) 4H-SiC or 6H-SiC substrates by continuous feed physical vapour transport process and the vapour-liquid-solid mechanism, respectively, and (ii) 3C-SiC wafer with (100) orientation from HOYA. The structural and optical investigation showed that (i) on the (111) substrates, due to the appearance of silicon and 6H-SiC inclusions, a layer which consisted of a sequence of long period polytypes was formed. The dominant polytype formed was 21R-SiC, which after successive transformation to 39R- and 57R- SiC led to the formation of 6H-SiC on the top of the layer. (ii) On the (100) substrates, a 3C-SiC layer with comparatively uniform defect density was formed. The main defects were stacking faults and their density was reducing during the process.

On the Nanostructure of SiC

2010 ◽  
Vol 12 ◽  
pp. 99-104
Author(s):  
Maya Marinova ◽  
Efstathios K. Polychroniadis
Keyword(s):  
Silicon Carbide ◽  
Liquid Phase ◽  
Structural Properties ◽  
Liquid Phase Epitaxy ◽  
Stacking Faults ◽  
Growth Conditions ◽  
Small Energy ◽  
Long Period ◽  
Stacking Order

The present work deals with the structural properties of silicon carbide in nanoscale dimensions. The examined crystals were 6H-SiC grown by Liquid Phase Epitaxy. The study was concentrated on the stacking faults and any other differences from the “correct” stacking order of the Si-C bilayers for this polytype. Three main types of stacking faults were observed: (i) Cubic lamellae with thickness of four and two Si-C bilayers, always occurring in reverse stacking with respect to each other and separated by at least one unit cell of 6H-SiC; (ii) “twinned” 6H-SiC lamellae separated by a two-bilayer thick cubic inclusion. As a result the sequence in the “twinned” 6H-SiC changes from (3+3-) to (3-3+). (iii) Lamellae showing fringes, the interrelated distance of which suggests inclusion with sequence (22). Further, a high variety of sequences was found, leading to the appearance of rare long period polytypes or individual lamellae having their “own” stacking inside the 6H-SiC matrix. These nanostructured faults which deteriorate the quality of the grown material indicate also their “sensitivity” to any small or even infinitesimal change of the growth conditions, due to the very small energy among them.

Tem Observation of defects in InGaAsP and InGaP Crystals on GaAs Substrates Grown by Liquid Phase Epitaxy

1983 ◽  
Vol 31 ◽  
Author(s):  
O. Ueda ◽  
S. Isozumi ◽  
S. Komiya ◽  
T. Kusunoki ◽  
I. Umebu
Keyword(s):  
Liquid Phase ◽  
Liquid Phase Epitaxy ◽  
Gaas Substrate ◽  
Stacking Faults ◽  
Dislocation Loops ◽  
Gaas Substrates ◽  
Modulated Structures ◽  
Lattice Matched

ABSTRACTDefects in InGaAsP and InGaP crystals lattice-matched to (001)-oriented GaAs substrate successfully grown by liquid phase epitaxy, have been investigated by TEM and STEM/EDX. Typical defects observed by TEM are composition-modulated structures, dislocation loops, non-structural microdefects, and stacking faults.

Optical Investigation of Electronic Properties in Bulk and Surface Region of Sublimation-Grown 3C-SiC Crystals

2009 ◽  
Vol 615-617 ◽  
pp. 303-306 ◽  
Author(s):  
Georgios Manolis ◽  
Kęstutis Jarašiūnas ◽  
Irina G. Galben-Sandulache ◽  
Didier Chaussende
Keyword(s):  
Carrier Density ◽  
Defect Density ◽  
Surface Region ◽  
Carrier Dynamics ◽  
Optical Investigation ◽  
Extended Defects ◽  
A Value ◽  
Continuous Feed ◽  
The Given

We applied a picosecond dynamic grating technique for studies of nonequilibrium carrier dynamics in a 0.8 mm thick bulk 3C-SiC crystal grown by the continuous feed physical vapor transport (CF-PVT) on 6H-SiC (0001) substrate. Investigation of carrier dynamics at surface or bulk excitation conditions was performed for excess carrier density in range from ~ 1017 cm-3 to ~ 1020 cm3 using for excitation weakly or strongly absorbed illumination. In DPBs free domains, the bipolar diffusion coefficient and carrier lifetime value at 300K were found gradually increasing with carrier density. The bipolar mobility vs. temperature dependence, μ. ~ T -k, provided a value k = 1.2 - 2 in range T < 100 K, thus indicating a negligible scattering by point and extended defects. These data indicated strong contribution of the carrier-density dependent but not defect-density governed scattering mechanisms, thus indicating high quality of the CF-PVT grown bulk cubic SiC. These studies were found in good correlation with the structural and photoluminescence characterization of the given crystal.

On the Polytypic Transformations in SiC

2012 ◽  
Vol 18-19 ◽  
pp. 89-96
Author(s):  
Maya Marinova ◽  
Alkyoni Mantzari ◽  
Ariadne Andreadou ◽  
Efstathios K. Polychroniadis
Keyword(s):  
Liquid Phase ◽  
Liquid Phase Epitaxy ◽  
Growth Conditions ◽  
Small Energy ◽  
Long Period ◽  
Stacking Order

In the present work we report on the polytypic transformations taking place in nanoscale dimensions within 6H-SiC crystals. The examined crystals were grown by Liquid Phase Epitaxy using a mixture of Si and Al as solvents. The study concentrated on the differences from the “correct” stacking order of the Si-C bilayers for 6H-SiC leading to the formation of other polytypes. A great variety of sequences was found, which resulted to the appearance of rare short and long period polytypes or individual lamellae having their “own” stacking inside the 6H-SiC matrix. These nanostructured faults which deteriorate the quality of the grown material indicate also their “sensitivity” to any small or even infinitesimal change of the growth conditions, due to the very small energy among them.

PVT-Growth and Characterization of Single Crystalline 3C-SiC on a (0001) 6H-SiC Substrate

2005 ◽  
Vol 483-485 ◽  
pp. 319-322 ◽  
Author(s):  
Efstathios K. Polychroniadis ◽  
Alkyoni Mantzari ◽  
A. Freudenberg ◽  
Jürgen Wollweber ◽  
R. Nitschke ◽  
...  
Keyword(s):  
Defect Density ◽  
Stacking Faults ◽  
Rapid Decrease ◽  
Crystallographic Direction ◽  
Vapour Transport ◽  
Direction Parallel ◽  
Transmission Electron ◽  
Nitrogen Donor ◽  
Capacitance Voltage

The aim of the present work is to grow 3C-SiC on (0001) 6H-SiC seeds using the Physical Vapour Transport (PVT) method and to study the electrical and structural properties of the grown material. Photoluminescence (PL)-mappings reveal that the overgrown layer consists predominantly of the 3C-SiC polytype and capacitance-voltage (C-V) measurements result in a net nitrogen donor concentration of 1x1016cm-3. Transmission Electron Microscopy (TEM) observations also confirm that the overgrown layer is of the 3C-SiC polytype having the cubic [111] crystallographic direction parallel to the c-axis of the 6H-SiC substrate. In some cases, twin crystals of 3C-SiC are formed immediately after the interface and, in a few cases, small 6H-SiC inclusions are observed in the cubic film having the same orientation as the substrate. The film near the substrate/overgrown interface shows a high density of defects such as dislocations and stacking faults (SF’s), which propagate into the overgrown layer. Finally although there is a rapid decrease of the defect density within the first 60 µm from the interface, the SF density remains almost constant within the last 100 µm below the surface.

Quality Investigation of 3C-SiC Crystals Grown by CF-PVT Technique

2011 ◽  
Vol 679-680 ◽  
pp. 20-23
Author(s):  
Irina G. Galben-Sandulache ◽  
Maya Marinova ◽  
Alkyoni Mantzari ◽  
Guoli L. Sun ◽  
Ariadne Andreadou ◽  
...  
Keyword(s):  
Nitrogen Doping ◽  
Structural Investigation ◽  
Defect Density ◽  
Stacking Faults ◽  
Crystalline Quality ◽  
Optical Investigation ◽  
Hexagonal Polytype ◽  
Transmission Electron ◽  
Good Crystalline Quality ◽  
Crystallographic Planes

This work presents the crystalline quality investigation of 3C-SiC unseeded crystals grown from vapor phase. Samples were polished after different crystallographic planes from crystals grown with or without nitrogen flow. The structural and optical investigation showed that the central part of the samples exhibited a very good crystalline quality. The best samples proved to be the {100} growth sectors where the only defects found were stacking faults with a defect density under 103 cm-1. At the edges, i.e. between two adjacent growth sectors, structural investigation by transmission electron microscopy revealed stacking faults and hexagonal polytype inclusions. The nitrogen doping was found not to have an influence on the crystalline quality.

LPE of Silicon Carbide Using Diluted Si-Ge Flux

2005 ◽  
Vol 483-485 ◽  
pp. 133-136 ◽  
Author(s):  
Octavian Filip ◽  
Boris M. Epelbaum ◽  
Matthias Bickermann ◽  
Albrecht Winnacker
Keyword(s):  
Growth Rate ◽  
Silicon Carbide ◽  
Liquid Phase ◽  
Epitaxial Growth ◽  
Liquid Phase Epitaxy ◽  
Vapour Transport ◽  
Growth Morphology ◽  
Effective Technique ◽  
Flux Composition ◽  
Melt Composition

Epitaxial growth of 4H-SiC has been carried out at temperatures up to 1650 oC on 4HSiC substrates dipped in strongly diluted Si-based solutions. Liquid Phase Epitaxy (LPE) in conditions of low supersaturation was shown to be an effective technique to overgrow micropipe defects (MPs) in SiC wafers prepared by the Physical Vapour Transport (PVT) technique. The aim of this work was to investigate the SiC growth morphology and the dependence of MP elimination efficiency on Si-Ge flux composition. Macroscopically flat, single crystalline SiC layers of a thickness up to 10 µm were grown with a growth rate of about 0.5 µm/h. Stepped growth morphology was observed independent of the melt composition. Micropipes with the diameter below 5 µm were closed with an efficiency of about 80%. SEM investigations as well as inspection under reflected/transmitted light did not show any specific distortion of the growth morphology at the micropipe healing place.

Nitrogen Doping of 3C-SiC Single Crystals Grown by CF-PVT

2009 ◽  
Vol 615-617 ◽  
pp. 45-48 ◽  
Author(s):  
Jessica Eid ◽  
Irina G. Galben-Sandulache ◽  
Georgios Zoulis ◽  
Teddy Robert ◽  
Didier Chaussende ◽  
...  
Keyword(s):  
Single Crystals ◽  
Nitrogen Doping ◽  
Structural Defects ◽  
Optical Investigation ◽  
Vapour Transport ◽  
Nitrogen Flow Rate ◽  
Continuous Feed ◽  
Cubic Silicon Carbide ◽  
Koh Etching ◽  
Transport Method

We present a structural and optical investigation of nitrogen-doped single crystals of cubic silicon carbide prepared by the continuous feed - physical vapour transport method. Self-nucleated crystals were produced which exhibited well faceted square and triangular shapes. KOH etching was used to characterize the structural defects, like stacking faults and dislocations. The effect of changing the nitrogen flow rate on the different crystalline orientations was investigated by Raman spectroscopy and low temperature photoluminescence techniques.

TEM study of very thin InGaAsP layers grown by liquid-phase epitaxy

1990 ◽  
Vol 48 (4) ◽  
pp. 672-673
Author(s):  
N.A. Bert ◽  
A.O. Kosogov
Keyword(s):  
Liquid Phase ◽  
Liquid Phase Epitaxy ◽  
Chemical Vapor ◽  
Growth Conditions ◽  
Dark Field ◽  
Organic Chemical ◽  
Simple Liquid ◽  
Cross Sectional ◽  
Conventional Procedure ◽  
Double Heterostructures

The very thin (<100 Å) InGaAsP layers were grown not only by molecular beam epitaxy and metal-organic chemical vapor deposition but recently also by simple liquid phase epitaxy (LPE) technique. Characterization of their thickness, interfase abruptness and lattice defects is important and requires TEM methods to be used.The samples were InGaAsP/InGaP double heterostructures grown on (111)A GaAs substrate. The exact growth conditions are described in Ref.1. The salient points are that the quarternary layers were being grown at 750°C during a fast movement of substrate and a convection caused in the melt by that movement was eliminated. TEM cross-section specimens were prepared by means of conventional procedure. The studies were conducted in EM 420T and JEM 4000EX instruments.The (200) dark-field cross-sectional imaging is the most appropriate TEM technique to distinguish between individual layers in 111-v semiconductor heterostructures.

Sign in / Sign up

Export Citation Format

Share Document