The Experts below are selected from a list of 7053 Experts worldwide ranked by ideXlab platform

J E Cotter - One of the best experts on this subject based on the ideXlab platform.

  • investigations of parasitic Shunt Resistance in n type buried contact solar cells
    Progress in Photovoltaics, 2006
    Co-Authors: P J Cousins, J E Cotter
    Abstract:

    It has been shown that n-type laser-grooved buried contact solar cells exhibit a high-efficiency potential, both on interdigitated backside buried contact (IBBC) and double-sided buried contact (DSBC) cell structures. As the IBBC solar cell contains heavily doped, compensated regions, the Shunt mechanisms are more complicated, and are different from those of the conventional front-collecting-junction solar cells. In this paper, several Shunting mechanisms hindering the performances of the n-type buried contact solar cells are investigated and discussed. The main Shunting routes in n-type IBBC solar cells are concluded as follows: (1) the emitter contact metal touching the n-type substrate, which is either due to nonuniform boron deposition or diffusion-induced misfit dislocations; (2) the base contact metal touching the p + emitter, attributed to either the phosphorus groove diffusion being unable to compensate for the boron emitter diffusion, or the junction depth located in the diffusion overlap regions not deep enough to prevent nickel from spiking through the groove diffusion. The Shunt Resistance of the IBBC cells increased by more than two orders of magnitude after eliminating the Shunt mechanisms discussed in this study. This led to an improvement in fill factor from 0·71-0·73 to 0·74-0·76, and an increase of average absolute efficiency of more than 0·65%.

  • Investigations of parasitic Shunt Resistance in n‐type buried contact solar cells
    Progress in Photovoltaics: Research and Applications, 2006
    Co-Authors: Jiun-hua Guo, P J Cousins, J E Cotter
    Abstract:

    It has been shown that n-type laser-grooved buried contact solar cells exhibit a high-efficiency potential, both on interdigitated backside buried contact (IBBC) and double-sided buried contact (DSBC) cell structures. As the IBBC solar cell contains heavily doped, compensated regions, the Shunt mechanisms are more complicated, and are different from those of the conventional front-collecting-junction solar cells. In this paper, several Shunting mechanisms hindering the performances of the n-type buried contact solar cells are investigated and discussed. The main Shunting routes in n-type IBBC solar cells are concluded as follows: (1) the emitter contact metal touching the n-type substrate, which is either due to nonuniform boron deposition or diffusion-induced misfit dislocations; (2) the base contact metal touching the p + emitter, attributed to either the phosphorus groove diffusion being unable to compensate for the boron emitter diffusion, or the junction depth located in the diffusion overlap regions not deep enough to prevent nickel from spiking through the groove diffusion. The Shunt Resistance of the IBBC cells increased by more than two orders of magnitude after eliminating the Shunt mechanisms discussed in this study. This led to an improvement in fill factor from 0·71-0·73 to 0·74-0·76, and an increase of average absolute efficiency of more than 0·65%.

P J Cousins - One of the best experts on this subject based on the ideXlab platform.

  • investigations of parasitic Shunt Resistance in n type buried contact solar cells
    Progress in Photovoltaics, 2006
    Co-Authors: P J Cousins, J E Cotter
    Abstract:

    It has been shown that n-type laser-grooved buried contact solar cells exhibit a high-efficiency potential, both on interdigitated backside buried contact (IBBC) and double-sided buried contact (DSBC) cell structures. As the IBBC solar cell contains heavily doped, compensated regions, the Shunt mechanisms are more complicated, and are different from those of the conventional front-collecting-junction solar cells. In this paper, several Shunting mechanisms hindering the performances of the n-type buried contact solar cells are investigated and discussed. The main Shunting routes in n-type IBBC solar cells are concluded as follows: (1) the emitter contact metal touching the n-type substrate, which is either due to nonuniform boron deposition or diffusion-induced misfit dislocations; (2) the base contact metal touching the p + emitter, attributed to either the phosphorus groove diffusion being unable to compensate for the boron emitter diffusion, or the junction depth located in the diffusion overlap regions not deep enough to prevent nickel from spiking through the groove diffusion. The Shunt Resistance of the IBBC cells increased by more than two orders of magnitude after eliminating the Shunt mechanisms discussed in this study. This led to an improvement in fill factor from 0·71-0·73 to 0·74-0·76, and an increase of average absolute efficiency of more than 0·65%.

  • Investigations of parasitic Shunt Resistance in n‐type buried contact solar cells
    Progress in Photovoltaics: Research and Applications, 2006
    Co-Authors: Jiun-hua Guo, P J Cousins, J E Cotter
    Abstract:

    It has been shown that n-type laser-grooved buried contact solar cells exhibit a high-efficiency potential, both on interdigitated backside buried contact (IBBC) and double-sided buried contact (DSBC) cell structures. As the IBBC solar cell contains heavily doped, compensated regions, the Shunt mechanisms are more complicated, and are different from those of the conventional front-collecting-junction solar cells. In this paper, several Shunting mechanisms hindering the performances of the n-type buried contact solar cells are investigated and discussed. The main Shunting routes in n-type IBBC solar cells are concluded as follows: (1) the emitter contact metal touching the n-type substrate, which is either due to nonuniform boron deposition or diffusion-induced misfit dislocations; (2) the base contact metal touching the p + emitter, attributed to either the phosphorus groove diffusion being unable to compensate for the boron emitter diffusion, or the junction depth located in the diffusion overlap regions not deep enough to prevent nickel from spiking through the groove diffusion. The Shunt Resistance of the IBBC cells increased by more than two orders of magnitude after eliminating the Shunt mechanisms discussed in this study. This led to an improvement in fill factor from 0·71-0·73 to 0·74-0·76, and an increase of average absolute efficiency of more than 0·65%.

Gaudenzio Meneghesso - One of the best experts on this subject based on the ideXlab platform.

  • Influence of Shunt Resistance on the Performance of an Illuminated String of Solar Cells: Theory, Simulation, and Experimental Analysis
    IEEE Transactions on Device and Materials Reliability, 2014
    Co-Authors: Marco Barbato, Matteo Meneghini, Andrea Cester, Giovanna Mura, Enrico Zanoni, Gaudenzio Meneghesso
    Abstract:

    This paper presents an extensive study of how a solar cell with low Shunt Resistance can affect the performance and reliability of a solar panel. The analysis is based on both simulations and experimental tests and provides the following results: 1) the cell with low Shunt Resistance significantly reduces the efficiency of a panel; 2) this is particularly pronounced if the Shunted cell is partially shaded: in this case, the Shunt Resistance of the cell acts as a load for the entire panel; 3) in these conditions, the Shunted cell can significantly degrade: in fact, the small-size Shunt paths are crossed by a high current density, generated by the other cells in the panel, thus reaching high temperature levels. Stress tests have been also carried out to fully characterize the degradation process and its dynamics and to understand the physical origin of the failure of Shunted cells.

  • Effect of Shunt Resistance on the performance of mc-Silicon solar cells: a combined electro-optical and thermal investigation
    2012 38th IEEE Photovoltaic Specialists Conference, 2012
    Co-Authors: Marco Barbato, Matteo Meneghini, Valentina Giliberto, Daniele Giaffreda, Paolo Magnone, R. De Rose, Claudio Fiegna, Gaudenzio Meneghesso
    Abstract:

    In this paper we discuss the effect of Shunt Resistance on the electro-optical characteristics of multicrystalline silicon (mc-Si) solar cells at different illumination levels. The analysis is based on combined electro-optical characterization and thermographic measurements of solar cells with similar efficiencies, but with different Shunt Resistance levels. In order to understand how the Shunt Resistance can affect the performance of mc-Si solar cells, a special setup for J-V characterization at several illumination levels was developed. Results indicate that (i) a low Shunt Resistance is strongly correlated to the presence of hot spots, which can be identified by means of infrared thermography; (ii) solar cells with different Shunt Resistance levels can show significantly different fill factors and efficiencies, particularly at low irradiation levels. This can strongly influence the reliability of modules at low illumination conditions; (iii) the electrical characteristics of mc-Si solar cells can be modeled with good results, by considering the equivalent two-diode electrical model and solving it by a circuit simulator like SPICE.

O. Tari - One of the best experts on this subject based on the ideXlab platform.

  • an approach to the measurement of Shunt Resistance of individual subcells in thin film tandem devices
    Progress in Photovoltaics, 2015
    Co-Authors: S Daliento, Pierluigi Guerriero, V Dalessandro, O. Tari
    Abstract:

    In this paper, the selective illumination approach is adopted to separately extract the Shunt Resistance of the individual subcells belonging to a tandem cell. The method relies on simple theoretical considerations and is based on the measurement of the current–voltage characteristic of the tandem cell by alternately keeping one of the subcells under dark conditions. Numerical simulations are employed to support the reliability of the technique, which is experimentally tested on micromorph devices deposited onto glass covered by a V-shaped transparent conducting oxide and subject to different thermal treatments. Copyright © 2013 John Wiley & Sons, Ltd.

  • An approach to the measurement of Shunt Resistance of individual subcells in thin‐film tandem devices
    Progress in Photovoltaics: Research and Applications, 2013
    Co-Authors: Santolo Daliento, Vincenzo D'alessandro, Pierluigi Guerriero, O. Tari
    Abstract:

    In this paper, the selective illumination approach is adopted to separately extract the Shunt Resistance of the individual subcells belonging to a tandem cell. The method relies on simple theoretical considerations and is based on the measurement of the current–voltage characteristic of the tandem cell by alternately keeping one of the subcells under dark conditions. Numerical simulations are employed to support the reliability of the technique, which is experimentally tested on micromorph devices deposited onto glass covered by a V-shaped transparent conducting oxide and subject to different thermal treatments. Copyright © 2013 John Wiley & Sons, Ltd.

Jiun-hua Guo - One of the best experts on this subject based on the ideXlab platform.

  • Investigations of parasitic Shunt Resistance in n‐type buried contact solar cells
    Progress in Photovoltaics: Research and Applications, 2006
    Co-Authors: Jiun-hua Guo, P J Cousins, J E Cotter
    Abstract:

    It has been shown that n-type laser-grooved buried contact solar cells exhibit a high-efficiency potential, both on interdigitated backside buried contact (IBBC) and double-sided buried contact (DSBC) cell structures. As the IBBC solar cell contains heavily doped, compensated regions, the Shunt mechanisms are more complicated, and are different from those of the conventional front-collecting-junction solar cells. In this paper, several Shunting mechanisms hindering the performances of the n-type buried contact solar cells are investigated and discussed. The main Shunting routes in n-type IBBC solar cells are concluded as follows: (1) the emitter contact metal touching the n-type substrate, which is either due to nonuniform boron deposition or diffusion-induced misfit dislocations; (2) the base contact metal touching the p + emitter, attributed to either the phosphorus groove diffusion being unable to compensate for the boron emitter diffusion, or the junction depth located in the diffusion overlap regions not deep enough to prevent nickel from spiking through the groove diffusion. The Shunt Resistance of the IBBC cells increased by more than two orders of magnitude after eliminating the Shunt mechanisms discussed in this study. This led to an improvement in fill factor from 0·71-0·73 to 0·74-0·76, and an increase of average absolute efficiency of more than 0·65%.