The crystallization of hydrogenated amorphous silicon layers (a-Si:H) [1,2] deposited by plasma enhanced chemical vapor deposition (PECVD) is of great interest. Generally, laser or metals are used to induce crystallization in aSi:H films. We have found that films deposited at high rf power (> 0.2 W/cm2) by PECVD technique shows some crystallites embedded in a-Si:H matrix and their after its vac...

X-band rapid-scan EPR was implemented on a commercially available Bruker ELEXSYS E580 spectrometer. Room temperature rapid-scan and continuous-wave EPR spectra were recorded for amorphous silicon powder samples. By comparing the resulting signal intensities the feasibility of performing quantitative rapid-scan EPR is demonstrated. For different hydrogenated amorphous silicon samples, rapid-scan...

Infrared four-wave mixing experiments performed upon deuterated amorphous silicon layers (a-Si:D) reveal profound differences in the dynamics of Si-D stretch vibrations compared to those of analogous Si-H vibrational modes in hydrogenated amorphous silicon (a-Si:H). Remarkably, transient-grating measurements of the population decay rate of the Si-D vibrations show single-exponential decay direc...

The Meyer–Neldel rule (MNR) has been observed in recent calculations of the electrical conductivity of hydrogenated amorphous silicon. To elucidate the origin of this effect, we have performed comparative studies on crystalline Si and non-hydrogenated a-Si. We find that the MNR is not present in the crystal, and is present in a-Si. This suggests that the existence of localized states and the en...

From different sources of carbon , propane have been chosen to get a wider band gap amorphous silicon alloy . After analyzing the conductivity and optical gap variation with the doping ratio , the best were used to fabricate 5x5 cm solar cells . Those cells are connected to form 75 x 75 cm panels. Photo-oxidation were carried out using different sources as an accelerated method to study the met...

The authors demonstrate an optical manipulation mechanism of gas bubbles for microfluidic applications. Air bubbles in a silicone oil medium are manipulated via thermocapillary forces generated by the absorption of a laser in an amorphous silicon thin film. In contrast to previous demonstrations of optically controlled thermally driven bubble movement, transparent liquids can be used, as the th...

Reactively sputtered nickel oxide (NiOx) films provide transparent, antireflective, electrically conductive, chemically stable coatings that also are highly active electrocatalysts for the oxidation of water to O2(g). These NiOx coatings provide protective layers on a variety of technologically important semiconducting photoanodes, including textured crystalline Si passivated by amorphous silic...

A photoconductive effect is observed in tetrahedral amorphous carbon (ta-C) or amorphous diamond films with a high proportion of sp3 bonding and a structure analogous to amorphous silicon. The spectral response is shown to peak at around 750400 nm and extend into the near UV region. The maximum photoresponse coincides wit.h the optical absorption edge. The quantum efficiency of 300 nm thick fil...