2009, ISBN: 9781234137168

RareBooksClub. Paperback. New. This item is printed on demand. Paperback. 78 pages. Original publisher: Golden, CO : National Renewable Energy Laboratory, 2009 OCLC Number: (OCoLC)49556… More...

RareBooksClub. Paperback. New. This item is printed on demand. Paperback. 78 pages. Original publisher: Golden, CO : National Renewable Energy Laboratory, 2009 OCLC Number: (OCoLC)495568261 Subject: Photovoltaic cells -- Research. Excerpt: . . . in each deposition; specifically, constant in time, square root in time, linear in time, and quadratic in time. Each substrate was processed to yield more than 30 devices, and the properties of these were different because the plasma varied over the diameter of the substrate. This meant that the devices near the center of the substrate were more crystalline, while those near the edge were more amorphous. Table III lists the sample devices we received for study and their performance parameters. In each deposition Cell 74 was close to the center and thus had the highest crystalline fraction, Cell 94 had the highest amorphous fraction, and Cell 75 was an intermediate case. This is also indicated in the schematic of the cell positions shown in Fig. 1. We employed Raman spectroscopy at 785nm to quantify the crystalline and amorphous fractions for this set of samples. An example for the 15125 ( constant H dilution ) sample set is shown in Fig. 2. Here we compare the Raman spectra for the most crystalline ( 74 ) and most amorphous ( 94 ) sample device. Each of these spectra has been analyzed by separation into 2-11-1 Gaussian components centered at 480 cm ( I ) and 510 cm ( I ), and one A GB-1 Gaussian Lorentzian mixed component at 520 cm ( I ) as indicated by the green curves in Fig. C 2. For our crystalline volume fraction ( X ) estimates we used the expression: C X ( I I ) ( I I I ) taking 1. C C GB C GB A Based upon such analyses of the Raman spectra we have estimated the crystalline fraction for each of the nc-Si: H samples studied. The details of this analysis for the samples in Table III are tabulated in Table IV. The estimates of X for the samples listed in Tables I and II were C carried out in the same manner. 15125-74 FIG. 2. Raman spectra obtained at 785nm for two nc-Si: H . . . This item ships from La Vergne,TN., RareBooksClub<