Mansi Sharma; Deepika Chaudhary; S. Sudhakar; Preetam Singh; K. M. K. Srivatsa; Sushil Kumar
Abstract
The structural transition in accordance to nano sized grain distribution within the amorphous silicon matrix has been described on the basis of spectroscopic analysis as a result of variable input power applied during growth via plasma enhanced chemical vapor deposition (PECVD) process. For this, characterization ...
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The structural transition in accordance to nano sized grain distribution within the amorphous silicon matrix has been described on the basis of spectroscopic analysis as a result of variable input power applied during growth via plasma enhanced chemical vapor deposition (PECVD) process. For this, characterization techniques like micro-ellipsometer, Raman, Field emission Scanning electron microscope (FESEM), and Fourier transform infrared spectroscopy (FTIR) have been effectively utilized to identify transitions in these films particularly in terms of crystallite size (within 1-4 nm) and optical constants. These results indicate that at and above 30 W applied power the separation of two zones takes place as ultranano to nano, leading to the formation of denser matrix having uniformly distributed nano-crystallites. Moreover, these results indicate the presence of unrevealed fine crystallites (ultranano-crystalline phase) as a dominating part of grain boundaries, which may be as ultranano-crystallite phase. The blending of fine nano-crystallites within the amorphous phase might be the possible reason for the formation of nano-crystallites from ultranano-crystallites.
Saruchi Surbhi; Praveen Aghamkar; Sushil Kumar
Abstract
Nanomaterials and nanostructures have received steadily growing interests as a result of their peculiar and fascinating properties and applications. Neodymia-silica nanocomposites were prepared by sol-gel route followed by calcination. The samples were prepared with different concentration of dopant ...
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Nanomaterials and nanostructures have received steadily growing interests as a result of their peculiar and fascinating properties and applications. Neodymia-silica nanocomposites were prepared by sol-gel route followed by calcination. The samples were prepared with different concentration of dopant (Nd2O3) and calcined in a programmable furnace at 1000 °C for 5 h. The structural evolution of samples was investigated by employing techniques such as XRD, FTIR and TEM. X-ray diffraction patterns showed that the samples were nanocrystalline and the size of crystallites has been determined using Debye-Scherrer relation. The FTIR spectra confirmed the presence of functional groups of prepared material. The particle size of samples was also estimated through TEM analysis. It has been observed that crystallinity as well as particle size of the samples increases with increase in dopant concentration.
