In:
Journal of Nanoscience and Nanotechnology, American Scientific Publishers, Vol. 15, No. 10 ( 2015-10-01), p. 7699-7705
Abstract:
High-efficiency Si solar cells have attracted great attention from researchers, scientists, photovoltaic (PV) industry engineers for the past few decades. With thin wafers, surface passivation becomes necessary to increase the solar cells efficiency by overcoming several induced effects
due to associated crystal defects and impurities of c-Si. This paper discusses suitable passivation schemes and optimization techniques to achieve high efficiency at low cost. SiN x film was optimized with higher transmittance and reduced recombination for using as an effective
antireflection and passivation layer to attain higher solar cell efficiencies. The higher band gap increased the transmittance with reduced defect states that persisted at 1.68 and 1.80 eV in SiN x films. The thermal stability of SiN (Si-rich)/SiN (N-rich) stacks was also
studied. Si-rich SiN with a refractive index of 2.7 was used as a passivation layer and N-rich SiN with a refractive index of 2.1 was used for thermal stability. An implied V OC of 720 mV with a stable lifetime of 1.5 ms was obtained for the stack layer after firing. Si–N
and Si–H bonding concentration was analyzed by FTIR for the correlation of thermally stable passivation mechanism. The passivation property of spin coated Al 2 O 3 films was also investigated. An effective surface recombination velocity of 55 cm/s with a high density
of negative fixed charges ( Q f ) on the order of 9×10 11 cm −2 was detected in Al 2 O 3 films.
Type of Medium:
Online Resource
ISSN:
1533-4880
DOI:
10.1166/jnn.2015.11206
Language:
English
Publisher:
American Scientific Publishers
Publication Date:
2015
SSG:
11
