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Rare earth - doped silicon nitride for solar cell applications - DOC - DOC

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					Rare earth - doped silicon nitride for solar cell applications
A significant limitation of the present photovoltaic solar cells is that more than 50% of the solar cell spectrum is not used. A lot of research has been concerned on increasing of solar cells efficiency. Several techniques and materials have been used to fulfil this purpose. It has been reported the application of deposited silicon nitride at high deposition rate as bulk passivating antireflection coating. Investigation studies of a new class of nitride based phosphors shows that the emission wavelength can be tuned by changing the doping concentration. This means that the UV-blue radiation (350 to 500 nm) can be converted in green-red radiation (550-800 nm).

Material properties

Relative Intensity

Absorption (conversion layer)

Spectral response

(Silicon solar cell)

Emission (conversion layer)

300

400

500

600 700 800 Wavelenght (nm)

900

1000

Spectral conversion process: principle A research question is how to incorporate the ions during the film plasma deposition and how the efficiency conversion depends on the plasma parameters, film chemical and microstructure properties. Our new approach consists in combining the two properties of silicon nitride matrix in one approach: to use Expanding Thermal Plasma source (ETP) for deposition of rare earth doped silicon nitride thin films. Information about thickness, refractive index and chemical composition of the films, can be obtained using Spectroscopic Ellipsometry (SE) and Fourier Transform Infrared Spectroscopy (FTIR), respectively. People involved in the project: M.C.Petcu (Cristina) M.Sc. – Applied Physics Department, P&MP A. C. Bronneberg (Aafle) - Applied Physics Department, P&MP Dr. M. Creatore (Adriana) - Applied Physics Department, P&MP Dr. H.T. Hintzen (Bert) – Department of Chemical Engineering and Chemistry Prof. dr. ir. M.C. M van de Sanden (Richard) – Applied Physics Department, P&MP


				
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posted:12/22/2009
language:English
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