Highly conducting phosphorous doped n-type nc-Si:H films by HW-CVD for c-Si heterojunction solar cells

Phosphorous doped hydrogenated nanocrystalline silicon (nc-Si:H) films were prepared using the hot wire chemical vapor deposition (HW-CVD) method at a low substrate temperature of 200 degree C. The microstructure and opto-electrical properties of these films were systematically studied using Raman s...

Full description

Saved in:
Bibliographic Details
Published in:RSC advances 2012-01, Vol.2 (26), p.9873-9880
Main Authors: Waman, Vaishali S., Kamble, Mahesh M., Ghosh, Sanjay S., Mayabadi, Azam, Sathe, Vasant. G., Pathan, Habib M., Shinde, Shashikant D., Adhi, Kiran P., Jadkar, Sandesh R.
Format: Article
Language:English
Subjects:
Aluminum
Chemical vapor deposition
Heterojunctions
Nanocrystals
Photovoltaic cells
Silicon substrates
Solar cells
Spectroscopy
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Phosphorous doped hydrogenated nanocrystalline silicon (nc-Si:H) films were prepared using the hot wire chemical vapor deposition (HW-CVD) method at a low substrate temperature of 200 degree C. The microstructure and opto-electrical properties of these films were systematically studied using Raman spectroscopy, low angle XRD, high resolution transmission electron microscopy (HR-TEM), UV-Visible spectroscopy, Fourier transform infrared (FTIR) spectroscopy, dark conductivity and its activation energy measurements and Hall measurement as a function of PH sub(3) gas-phase ratio. It has been found that with an increase in the PH sub(3) gas-phase ratio, both the volume fraction of the crystallites and its size decrease, signifying that the phosphorous atom favors the growth of amorphization in the nanocrystalline Si network. At the optimized PH sub(3) gas-phase ratio we have obtained n-type nc-Si:H films with a band gap of similar to 1.84 eV, high dark conductivity ( similar to 6.78 S cm super(-1)) with low hydrogen content ( similar to 1.72 at. %), at a reasonably high deposition rate ( similar to 10 Aa s super(-1)). Finally, Al/ZnO:Al/n-nc-Si:H/buffer a-Si:H/p-c-Si/Al heterojunction solar cells were fabricated using the optimized n-layer, showing excellent photovoltaic performance with V sub(oc) = 719 mV, J sub(sc) = 9.94 mA cm super(-2), FF = 53.8%, and an energy conversion efficiency of 5.2%. These are very encouraging results for the future fabrication of high efficiency silicon heterojunction solar cells and thin film tandem solar cells.
ISSN:2046-2069
2046-2069
DOI:10.1039/c2ra21618c