Polymer-Derived Micro-Nano-Structured Si3N4/SiC-CompositeS

1994 ◽  
Vol 346 ◽  
Author(s):  
Axel Greiner ◽  
Joachim Bill ◽  
Ralf Riedel

ABSTRACTMicro-nano-structured Si3N4/SiC-composites were prepared by liquid phase sintering of either amorphous, polymer derived Si-C-N powder or SiC1+x coated OC-Si3N4 powder, followed by gas pressure sintering. The obtained microstructures were investigated by scanning and transmission electron microscopy (SEM, TEM). Nanosized SiC inclusions embedded in microcrystalline Si3N4 grains were analysed by elemental mapping with electron spectroscopie imaging (ESI).

Author(s):  
J. Bentley ◽  
E. A. Kenik ◽  
K. Siangchaew ◽  
M. Libera

Quantitative elemental mapping by inner shell core-loss energy-filtered transmission electron microscopy (TEM) with a Gatan Imaging Filter (GIF) interfaced to a Philips CM30 TEM operated with a LaB6 filament at 300 kV has been applied to interfaces in a range of materials. Typically, 15s exposures, slit width Δ = 30 eV, TEM magnifications ∼2000 to 5000×, and probe currents ≥200 nA, were used. Net core-loss maps were produced by AE−r background extrapolation from two pre-edge windows. Zero-loss I0 (Δ ≈ 5 eV) and “total” intensity IT (unfiltered, no slit) images were used to produce maps of t/λ = ln(IT/I0), where λ is the total inelastic mean free path. Core-loss images were corrected for diffraction contrast by normalization with low-loss images recorded with the same slit width, and for changes in thickness by normalization with t/λ, maps. Such corrected images have intensities proportional to the concentration in atoms per unit volume. Jump-ratio images (post-edge divided by pre-edge) were also produced. Spectrum lines across planar interfaces were recorded with TEM illumination by operating the GIF in the spectroscopy mode with an area-selecting slit oriented normal to the energy-dispersion direction. Planar interfaces were oriented normal to the area-selecting slit with a specimen rotation holder.


MRS Bulletin ◽  
2020 ◽  
Vol 45 (9) ◽  
pp. 746-753
Author(s):  
Taylor J. Woehl ◽  
Trevor Moser ◽  
James E. Evans ◽  
Frances M. Ross

Abstract


1991 ◽  
Vol 238 ◽  
Author(s):  
M. Albrecht ◽  
H. P. Strunk ◽  
P. O. Hansson ◽  
E. Bauser

ABSTRACTThe initial stages of heteroepitaxial growth of Ge0.85 Si0.15 on Si(001) grown from Bi solution (liquid phase epitaxy) are studid by transmission electron microscopy. Stranski-Krastanov growth is observed to take place. After growth of a pseudomorphic Ge0.85 Si0.15 layer of 4 monolayer thickness, islands form and grow pseudomorphically up to a thickness of 30 nm. Then first misfit dislocations form. The formation process of these dislocations is analyzed and discussed in terms of half loop nucleation at the surface and dislocation glide. Evidence for glide on (110) planes is put forward.


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