Methods of using selective optical excitation in deposition processes and the detection of new compounds.

摘要

The present invention generally relates to the use of fluorescence signals obtained by selective optical excitation to detect and monitor a species present during a flow reaction or decomposition of various reactants. These reactions were analyzed in situ using a tunable laser as a selective excitation source in combination with a reactor inducing such reactions with a diffusion flame or a plasma. The resultant spectra and analysis presented herein demonstrates the detection of new compositions like SiHF in the gas phase. The invention allows for pinpoint spatial probing of the reactor without perturbing the reaction. Thus, a deposition process can be controlled by monitoring a selected species and adjusting the deposition reaction parameters in response to the species' mere detection or relative concentration. The invention also contemplates perturbing deposition reactions by selectively exciting a species present in the deposition reaction to modify the deposited material so that the quality of the deposited material improves. Specifically, improved photovoltaic devices which include photoconductive material made in accordance with the present invention are disclosed herein.