Surface Morphology and Optical Reflection of Thermally Evaporated Thin Film Al-Doped Silicon on Plastic Substrates for Solar Cells Applications

ABSTRACTA cross sectional TME study has been conducted into the structure and morphology of p- and i-type a-Si:H layers of device quality deposited on textured TCO on glass. The layer thickness over peaks is shown to be equivalent to that for flat regions, while defective regions are found in narrow valleys, initiating from the pit of the valleys. These regions may act as regions of excessive recombination and/or shunting regions, thus leading to a reduced Voc and fill factor in thin solar cells. A cosine relationship was found between the deposited thickness and the facet angles of the surface TCO crystals. It is concluded that for best performance of the deposited layer, the deposition has to be completely isotropie, and that the preferred surface morphology of textured TCO be sharp peaks with wider valleys.

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Mixed phase silicon oxide layers for thin-film silicon solar cells

MRS Proceedings ◽

10.1557/opl.2011.813 ◽

2011 ◽

Vol 1321 ◽

Cited By ~ 17

Author(s):

Peter Cuony ◽

Duncan T.L. Alexander ◽

Linus Löfgren ◽

Michael Krumrey ◽

Michael Marending ◽

...

Keyword(s):

Thin Film ◽

Solar Cells ◽

Silicon Oxide ◽

Nanocrystalline Silicon ◽

Silicon Solar Cells ◽

Microstructural Properties ◽

Microcrystalline Silicon ◽

Thin Film Silicon ◽

Transmission Electron ◽

Doped Silicon

ABSTRACTLower absorption, lower refractive index and tunable resistance are three advantages of doped silicon oxide containing nanocrystalline silicon grains (nc-SiOx) compared to doped microcrystalline silicon, for the use as p- and n-type layers in thin-film silicon solar cells. In this study we show how optical, electrical and microstructural properties of nc-SiOx layers depend on precursor gas ratios and we propose a growth model to explain the phase separation in such films into Si-rich and O-rich regions as visualized by energy-filtered transmission electron microscopy.

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Amorphous Silicon, Microcrystalline Silicon, and Thin-Film Polycrystalline Silicon Solar Cells

MRS Bulletin ◽

10.1557/mrs2007.25 ◽

2007 ◽

Vol 32 (3) ◽

pp. 219-224 ◽

Cited By ~ 44

Author(s):

Ruud E.I. Schropp ◽

Reinhard Carius ◽

Guy Beaucarne

Keyword(s):

Thin Film ◽

Solar Cells ◽

Crystalline Silicon ◽

Low Cost ◽

Float Glass ◽

Film Material ◽

Microcrystalline Silicon ◽

Plastic Substrates ◽

Thin Film Silicon ◽

Amorphous Si

AbstractThin-film solar cell technologies based on Si with a thickness of less than a few micrometers combine the low-cost potential of thin-film technologies with the advantages of Si as an abundantly available element in the earth's crust and a readily manufacturable material for photovoltaics (PVs). In recent years, several technologies have been developed that promise to take the performance of thin-film silicon PVs well beyond that of the currently established amorphous Si PV technology. Thin-film silicon, like no other thin-film material, is very effective in tandem and triple-junction solar cells. The research and development on thin crystalline silicon on foreign substrates can be divided into two different routes: a low-temperature route compatible with standard float glass or even plastic substrates, and a high-temperature route (>600°C). This article reviews the material properties and technological challenges of the different thin-film silicon PV materials.

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Influence of Surface Morphology of Textured Substrate against Poly-Si Thin Film Solar Cells Performance

Materials Science Forum ◽

10.4028/www.scientific.net/msf.737.105 ◽

2013 ◽

Vol 737 ◽

pp. 105-109 ◽

Cited By ~ 1

Author(s):

Riza Muhida ◽

Toshihiko Toyama ◽

Hiroaki Okamoto

Keyword(s):

Thin Film ◽

Solar Cells ◽

Surface Morphology ◽

Light Trapping ◽

Photovoltaic Performance ◽

Thin Film Solar Cells ◽

Optical Absorption Coefficient ◽

Root Mean Square Roughness ◽

Textured Surface ◽

Si Thin Film

Since poly-Si is an indirect band gap material and has low optical absorption coefficient in the visible-infrared region, the light trapping in thin film poly-Si layer by using textured substrate is one of the important technical issue for achievement of high short current. Surface texture of a transparent conductive oxide (TCO) layer on a glass substrate as well as SnO2 with a large grain are usually utilized for the light-trapping technique, i.e., path lengths of the incident light in the poly-Si layer are effectively enhanced by the light-scattering at the textured surface. In this paper, a systematic investigation has been carried out concerning the relationship between poly-Si thin film solar cells performance and surface morphology of substrate texture as a function of root mean square roughness of substrate surface, in order to find the optimum textured substrate and realize the light trapping in the poly-Si solar cells. Furthermore, the influence of textured substrate on optical reflectance, poly-Si microstructure and photovoltaic performance are also discussed.

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