<abstract xmlns="http://www.w3.org/1999/xhtml">The improvement of optical confinement on the back crystalline silicon solar cell is one of the factors leading to its better performance. Porous silicon (PS) layer can be used as a back reflector (BR) in solar cells. In this work, single layers of porous silicon were grown by electrodeposition on a single crystalline silicon substrate. The measurement of the total reflectivity (RT) on Si/PS surface showed a significant improvement in optical confinement compared to that measured on Si/standard Al back surface field (BSF). The internal reflectivity (RB) extracted from total reflectivity measurements achieved 86 % for the optimized single PS layer (92 nm thick layer with 60 % porosity) in the wavelength range between 950 and 1200 nm. This improvement was estimated as more than 17 % compared to that measured on the surface of Si/BSF Al contact. To improve the stability and passivation properties of PS layer BR, silicon nitride layer (SiNx) was deposited by PECVD on a PS layer. The maximum measured total reflectivity for PS/SiNx achieved approximately 56 % corresponding to an improved RB of up to 83 %. The PS formation process in combination with the PECVD SiNx, can be applied in the photovoltaic cell technology and offer a promising technique to produce high-efficiency and low-cost c-Si solar cells.</abstract>

The improvement of optical confinement on the back crystalline silicon solar cell is one of the factors leading to its better performance. Porous silicon (PS) layer can be used as a back reflector (BR) in solar cells. In this work, single layers of porous silicon were grown by electrodeposition on a single crystalline silicon substrate. The measurement of the total reflectivity (RT) on Si/PS surface showed a significant improvement in optical confinement compared to that measured on Si/standard Al back surface field (BSF). The internal reflectivity (RB) extracted from total reflectivity measurements achieved 86 % for the optimized single PS layer (92 nm thick layer with 60 % porosity) in the wavelength range between 950 and 1200 nm. This improvement was estimated as more than 17 % compared to that measured on the surface of Si/BSF Al contact. To improve the stability and passivation properties of PS layer BR, silicon nitride layer (SiNx) was deposited by PECVD on a PS layer. The maximum measured total reflectivity for PS/SiNx achieved approximately 56 % corresponding to an improved RB of up to 83 %. The PS formation process in combination with the PECVD SiNx, can be applied in the photovoltaic cell technology and offer a promising technique to produce high-efficiency and low-cost c-Si solar cells.

Optical properties of porous Si/PECVD SiNX:H reflector on single crystalline Si for solar cells

Laboratoire des Matériaux et Structure des Systčmes Electromécaniques et leur Fiabilité LMSSEF Université Larbi Ben Mhidi,

Institut des nanotechnologies de Lyon, INL, CNRS-UMR5270, INSA, Villeurbanne F-69621,

Materials Science-Poland

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Optical properties of porous Si/PECVD SiN:H reflector on single crystalline Si for solar cells

The improvement of optical confinement on the back crystalline silicon solar cell is one of the factors leading to its better performance. Porous silicon (PS)...

	Weighted Thickness average R [%]	[nm] Thickness SE	[nm] SEM
1.3	52	96	79
4	50	334	329
7	48	599	560
8	47	685	660
10	44	836	836

Optical properties of porous Si/PECVD SiN_X:H reflector on single crystalline Si for solar cells

Article Category: Research Article

Publicado en línea: 27 abr 2016

Páginas: 94 - 100

Recibido: 05 jun 2015

Aceptado: 18 dic 2015

DOI: https://doi.org/10.1515/msp-2016-0054

Palabras clave
porous silicon, light trapping, SiN, total reflectivity, internal reflectivity

© Wroclaw University of Technology

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Fig 1

Fig 2

Fig 3

Fig 4

Fig 5

Fig 6

Fig 7

Fig 8

Weighted average reflectivity calculated from the measured total reflectivity in the wavelength range between 800 and 1200 nm, for various thicknesses of PS layers.

Optical properties of porous Si/PECVD SiNX:H reflector on single crystalline Si for solar cells

Article Category: Research Article

Publicado en línea: 27 abr 2016

Páginas: 94 - 100

Recibido: 05 jun 2015

Aceptado: 18 dic 2015

DOI: https://doi.org/10.1515/msp-2016-0054

Palabras claveporous silicon, light trapping, SiN, total reflectivity, internal reflectivity

© Wroclaw University of Technology

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Fig 1

Fig 2

Fig 3

Fig 4

Fig 5

Fig 6

Fig 7

Fig 8

Weighted average reflectivity calculated from the measured total reflectivity in the wavelength range between 800 and 1200 nm, for various thicknesses of PS layers.

Optical properties of porous Si/PECVD SiN_X:H reflector on single crystalline Si for solar cells

Palabras clave
porous silicon, light trapping, SiN, total reflectivity, internal reflectivity