Time filter

Source Type

Kang M.H.,Georgia Institute of Technology | Hong J.,Sixtron Advanced Materials Inc. | Cooper I.,Georgia Institute of Technology | Ebong A.,University of North Carolina at Charlotte | And 3 more authors.
Journal of the Electrochemical Society | Year: 2011

Lifetime and efficiency degradation under illumination in boron (B) doped Czhochralski (Cz) based solar cells is well established and is attributed to the formation of boron and oxygen complexes. This paper shows that injection of carbon (C) from a SiCxNy antireflection (AR) coating can diffuse into the bulk silicon (Si) during high temperature contact firing and may compete with boron to reduce the number of B-O2i defects and the corresponding LID. Reduction in LID due to additional carbon in the bulk was investigated quantitatively by fabrication and analysis of boron doped Cz cells coated with conventional SiNx as well as novel SiCxN y films deposited from an organosilicon source. SiCxN y coated cells showed an average loss of 0.1 in absolute efficiency due to LID compared to 0.3 loss in absolute efficiency for the counterpart SiNx coated solar cells fabricated on ∼2 cm Cz Si with an oxygen concentration of ∼7 1017 cm-3. This phenomenon is attributed to the formation of carbon-oxygen dimmers (C-O2i) which compete with the formation of B-O2i complexes. © 2011 The Electrochemical Society. Source

Kang M.H.,Georgia Institute of Technology | Rohatgi A.,Georgia Institute of Technology | Rohatgi A.,Suniva Inc. | Hong J.,Sixtron Advanced Materials Inc. | And 4 more authors.
Progress in Photovoltaics: Research and Applications | Year: 2013

Screen-printed metal contact formation through a carbon containing antireflection coating was investigated for silicon solar cells by fabricating conventional carbon-free SiNx and carbon-rich SiCxN y film. An appreciable difference was found in the average shunt resistance (Rsh), which was about an order of magnitude higher for SiCxNy-coated solar cells relative to the counterpart SiNx-coated solar cells. Series resistance (Rs) and fill factor (FF) were comparable for both antireflection coatings but the starting efficiency of SiCxNy-coated cell was ~0·2% lower because of slightly inferior surface passivation. However, SiCxN y-coated solar cells showed less degradation under lower illumination (<1000 W/m2) compared with the SiNx-coated cells due to reduced FF degradation under low illumination. Theoretical calculations in this paper support that this is a direct result of high Rsh. Detailed photovoltaic system and cost modeling is performed to quantify the enhanced energy production and the reduced levelized cost of electricity due to higher shunt resistance of the SiCxNy-coated cells. It is shown that Rsh value below 30 Ω (7000 Ω cm2 for 239 cm2 cell) can lead to appreciable loss in energy production in regions of low solar insolation. Copyright © 2011 John Wiley & Sons, Ltd. Source

Kang M.H.,Georgia Institute of Technology | Hong J.,Sixtron Advanced Materials Inc. | Ebong A.,Georgia Institute of Technology | Rounsaville B.,Georgia Institute of Technology | And 3 more authors.
Conference Record of the IEEE Photovoltaic Specialists Conference | Year: 2010

Boron doped Czochralski (Cz) silicon solar cells undergo efficiency degradation under illumination. The light induced degradation (LID) is related to the formation of Bs-O2i complexes which act as a strong recombination centers. This paper shows that carbon present inside the SiC xNy films deposited from polymer solid or liquid source reduce the LID in boron doped Cz solar cells. The in situ grown carbon in the antireflection (AR) films provides a source of additional carbon which gets incorporated into the bulk silicon (Si) during the cell processing. This carbon competes with boron to form a carbonoxygen related complex and reduces the Bs-O2i concentration and the associated LID compared to conventional SiNx coated solar cells. SiCxNy coated solar cells showed 0.1% loss in absolute efficiency due to LID relative to 0.3% degradation in the counterpart SiNx coated solar cells on 2 Ω-cm boron doped Cz material. © 2010 IEEE. Source

Lair Liquide Societe Anonyme Pour Letude Et Lexploitation Des Procedes Georges Claude and SiXtron Advanced Materials Inc. | Date: 2010-03-23

apparatus for generating gases, namely, gasifers and replacement parts therefor. apparatus for generating gases, namely, gasifiers for laboratory use and replacement parts therefor.

Awad Y.,Sixtron Advanced Materials Inc. | Awad Y.,Universite de Sherbrooke | El Khakani M.A.,INRS - Institute National de la Recherche Scientifique | Scarlete M.,Bishops University | And 5 more authors.
Journal of Applied Physics | Year: 2010

Amorphous silicon carbon nitride (a-SiCN:H) films were synthesized using vapor transport-chemical vapor deposition technique. Poly(dimethylsilane) was used as a single source for both Si and C. NH3 gas diluted in Ar is used as a source for nitrogen. The composition and bonding states are uniquely characterized with respect to NH3/Ar ratio by Fourier transform infrared spectroscopy (FTIR) and x-ray photoelectron spectroscopy (XPS). Spectral deconvolution is used to extract the individual components of the FTIR and XPS spectra. For instance, the FTIR spectra show a remarkable drop in the intensity of Si-C vibration accompanied by the formation of further bonds including Si-N, C-N, C=N, C≡N, and N-H with increasing NH3/Ar ratio. Moreover, the XPS spectra show the existence of different chemical bonds in the a-SiCN:H films such as Si-C, Si-N, C-N, C=N, and C=C. Both FTIR and XPS data demonstrate that the chemical bonding in the amorphous matrix is more complicated than a collection of single Si-C Si-N, or Si-H bonds. © 2010 American Institute of Physics. Source

Discover hidden collaborations