Pub Date : 2013-01-01DOI: 10.1109/pvsc-vol2.2012.6656716
Kihwan Kim, Evan Kimberly, Andrew Damiani, G. Hanket, W. Shafarman
A three-step H2Se/Ar/H2S reaction is used to process Cu-In-Ga metal precursors to form Cu(In,Ga)(Se,S)2 films over 10 × 10 cm2 substrates. The 1st selenization step gives fine microstructure with Ga accumulation near the Mo back contact, primarily in a Cu9Ga4 phase. Significant grain growth with homogenous through-film Ga distribution is obtained by the 2nd Ar annealing step. The 3rd sulfization step completes the reaction process and incorporates S near the Cu(In,Ga)Se2 surface. The resulting films show good adhesion and yielded devices with η = 14.8% and VOC = 612 mV.
{"title":"+Three-step H2Se/Ar/H2S reaction of metal precursors for large area Cu(In,Ga)(Se,S)2 with uniform Ga distribution","authors":"Kihwan Kim, Evan Kimberly, Andrew Damiani, G. Hanket, W. Shafarman","doi":"10.1109/pvsc-vol2.2012.6656716","DOIUrl":"https://doi.org/10.1109/pvsc-vol2.2012.6656716","url":null,"abstract":"A three-step H<inf>2</inf>Se/Ar/H<inf>2</inf>S reaction is used to process Cu-In-Ga metal precursors to form Cu(In,Ga)(Se,S)<inf>2</inf> films over 10 × 10 cm<sup>2</sup> substrates. The 1<sup>st</sup> selenization step gives fine microstructure with Ga accumulation near the Mo back contact, primarily in a Cu<inf>9</inf>Ga<inf>4</inf> phase. Significant grain growth with homogenous through-film Ga distribution is obtained by the 2<sup>nd</sup> Ar annealing step. The 3<sup>rd</sup> sulfization step completes the reaction process and incorporates S near the Cu(In,Ga)Se<inf>2</inf> surface. The resulting films show good adhesion and yielded devices with η = 14.8% and V<inf>OC</inf> = 612 mV.","PeriodicalId":6420,"journal":{"name":"2012 IEEE 38th Photovoltaic Specialists Conference (PVSC) PART 2","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91498096","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-01-01DOI: 10.1109/pvsc-vol2.2012.6656780
J. Seiffe, F. Pillath, D. Trogus, A. Brand, C. Savio, M. Hofmann, J. Rentsch
In this study, the feasibility of creating one dielectric layer system acting simultaneously as antireflection coating, phosphorous doping source, masking against metal plating, and surface passivation is presented. Moreover, a similar layer stack is described, which behaves as rear-side surface passivation, boron dopant source, and internal reflection mirror. The optical characteristics of these layers are especially investigated and optimized for a solar cell's front- and rear-side coating. By consequent use of the multifunctional layers, a totally diffused solar cell with rear-side passivation and local rear contacts can be produced using only one wet chemical bath sequence, one multilayer vacuum step, and one high-temperature process. We present the first proof of concept for such a solar cell production using multifunctional plasma-enhanced chemical vapor deposition layers resulting already in a conversion efficiency of 18.3%.
{"title":"Multifunctional PECVD layers: Dopant source, passivation, and optics","authors":"J. Seiffe, F. Pillath, D. Trogus, A. Brand, C. Savio, M. Hofmann, J. Rentsch","doi":"10.1109/pvsc-vol2.2012.6656780","DOIUrl":"https://doi.org/10.1109/pvsc-vol2.2012.6656780","url":null,"abstract":"In this study, the feasibility of creating one dielectric layer system acting simultaneously as antireflection coating, phosphorous doping source, masking against metal plating, and surface passivation is presented. Moreover, a similar layer stack is described, which behaves as rear-side surface passivation, boron dopant source, and internal reflection mirror. The optical characteristics of these layers are especially investigated and optimized for a solar cell's front- and rear-side coating. By consequent use of the multifunctional layers, a totally diffused solar cell with rear-side passivation and local rear contacts can be produced using only one wet chemical bath sequence, one multilayer vacuum step, and one high-temperature process. We present the first proof of concept for such a solar cell production using multifunctional plasma-enhanced chemical vapor deposition layers resulting already in a conversion efficiency of 18.3%.","PeriodicalId":6420,"journal":{"name":"2012 IEEE 38th Photovoltaic Specialists Conference (PVSC) PART 2","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86587201","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-01-01DOI: 10.1109/pvsc-vol2.2012.6656768
L. Nelson, Mark Frichtl, A. Panchula
Seasonal and short-term weather-related changes in the solar spectrum can induce shifts in the performance of photovoltaic (PV) systems that affect both annual energy predictions and system characterization. The spectral shift factor, which is a metric indicative of how much the performance of a PV system will vary from nameplate due to deviations from the ASTM G173 spectrum (air mass of 1.5), is predicted using TMY3 data and the simple model of the atmospheric radiative transfer for sunshine (SMARTS) model and is correlated with cadmium telluride (CdTe) PV system performance in four different climates. The predicted spectral shift factors for CdTe systems show improved performance in the late summer and early fall and diminished performance in the winter. These intraannual variations can be as large as ±3%, but annual spectral shift factors are typically within ± 1% of nameplate. The spectral shift factor of CdTe systems was found to be most sensitive to the precipitable water content of the atmosphere. Consequently, a parameterization of CdTe spectral shift factor as an exponential function of precipitable water is derived using the outputs of the SMARTS model in 11 locations. This parameterization is shown to predict observed monthly and daily fluctuations in CdTe PV performance. Future efforts will incorporate this methodology into energy predictions that will reduce uncertainty.
{"title":"Changes in cadmium telluride photovoltaic system performance due to spectrum","authors":"L. Nelson, Mark Frichtl, A. Panchula","doi":"10.1109/pvsc-vol2.2012.6656768","DOIUrl":"https://doi.org/10.1109/pvsc-vol2.2012.6656768","url":null,"abstract":"Seasonal and short-term weather-related changes in the solar spectrum can induce shifts in the performance of photovoltaic (PV) systems that affect both annual energy predictions and system characterization. The spectral shift factor, which is a metric indicative of how much the performance of a PV system will vary from nameplate due to deviations from the ASTM G173 spectrum (air mass of 1.5), is predicted using TMY3 data and the simple model of the atmospheric radiative transfer for sunshine (SMARTS) model and is correlated with cadmium telluride (CdTe) PV system performance in four different climates. The predicted spectral shift factors for CdTe systems show improved performance in the late summer and early fall and diminished performance in the winter. These intraannual variations can be as large as ±3%, but annual spectral shift factors are typically within ± 1% of nameplate. The spectral shift factor of CdTe systems was found to be most sensitive to the precipitable water content of the atmosphere. Consequently, a parameterization of CdTe spectral shift factor as an exponential function of precipitable water is derived using the outputs of the SMARTS model in 11 locations. This parameterization is shown to predict observed monthly and daily fluctuations in CdTe PV performance. Future efforts will incorporate this methodology into energy predictions that will reduce uncertainty.","PeriodicalId":6420,"journal":{"name":"2012 IEEE 38th Photovoltaic Specialists Conference (PVSC) PART 2","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89230629","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-01-01DOI: 10.1109/pvsc-vol2.2013.6656747
S. Hanni, D. Alexander, L. Ding, G. Bugnon, M. Boccard, C. Battaglia, P. Cuony, J. Escarré, G. Parascandolo, S. Nicolay, M. Cantoni, M. Despeisse, F. Meillaud, C. Ballif
This paper gives new insights into the role of both the microstructure and the interfaces in microcrystalline silicon (μc-Si) single-junction solar cells. A 3-D tomographic reconstruction of a μc-Si solar cell reveals the 2-D nature of the porous zones, which can be present within the absorber layer. Tomography thus appears as a valuable technique to provide insights into the μc-Si microstructure. Variable illumination measurements enable to study the negative impact of such porous zones on solar cells performance. The influence of such defectivematerial can bemitigated by suitable cell design, as discussed here. Finally, a hydrogen plasma cell post-deposition treatment is demonstrated to improve solar cells performance, especially on rough superstrates, enabling us to reach an outstanding 10.9% efficiency microcrystalline single-junction solar cell.
{"title":"On the interplay between microstructure and interfaces in high-efficiency microcrystalline silicon solar cells","authors":"S. Hanni, D. Alexander, L. Ding, G. Bugnon, M. Boccard, C. Battaglia, P. Cuony, J. Escarré, G. Parascandolo, S. Nicolay, M. Cantoni, M. Despeisse, F. Meillaud, C. Ballif","doi":"10.1109/pvsc-vol2.2013.6656747","DOIUrl":"https://doi.org/10.1109/pvsc-vol2.2013.6656747","url":null,"abstract":"This paper gives new insights into the role of both the microstructure and the interfaces in microcrystalline silicon (μc-Si) single-junction solar cells. A 3-D tomographic reconstruction of a μc-Si solar cell reveals the 2-D nature of the porous zones, which can be present within the absorber layer. Tomography thus appears as a valuable technique to provide insights into the μc-Si microstructure. Variable illumination measurements enable to study the negative impact of such porous zones on solar cells performance. The influence of such defectivematerial can bemitigated by suitable cell design, as discussed here. Finally, a hydrogen plasma cell post-deposition treatment is demonstrated to improve solar cells performance, especially on rough superstrates, enabling us to reach an outstanding 10.9% efficiency microcrystalline single-junction solar cell.","PeriodicalId":6420,"journal":{"name":"2012 IEEE 38th Photovoltaic Specialists Conference (PVSC) PART 2","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84025126","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-01-01DOI: 10.1109/pvsc-vol2.2013.6656781
P. Sinha, A. Meader, M. de Wild-Scholten
Life cycle water withdrawal for cadmium telluride photovoltaics (CdTe PV) ranges from approximately 382–425 L/MWh, with only ∼12% from direct on-site usage. The remainder is related to indirect waterwithdrawal from the use of grid electricity and raw materials throughout the product life cycle. Approximately half of life cycle water withdrawal is associated with module manufacturing, one-third from balance of systems (BOS), and the remainder from takeback and recycling. Primary contributors to life cycle water withdrawal are the use of grid electricity, glass, and on-site water during manufacturing; steel, copper, inverters, and on-site water in the BOS; and electricity, chemical use, and transport during takeback and recycling. During manufacturing, water consumption is approximately one quarter of withdrawal and is due to cooling tower water evaporation and site irrigation. When deployed in the U.S. Southwest, a CdTe PV array can provide net displacement of life cycle water withdrawal of over 1700–5600 L/MWh relative to grid electricity.
{"title":"Life cycle water usage in CdTe photovoltaics","authors":"P. Sinha, A. Meader, M. de Wild-Scholten","doi":"10.1109/pvsc-vol2.2013.6656781","DOIUrl":"https://doi.org/10.1109/pvsc-vol2.2013.6656781","url":null,"abstract":"Life cycle water withdrawal for cadmium telluride photovoltaics (CdTe PV) ranges from approximately 382–425 L/MWh, with only ∼12% from direct on-site usage. The remainder is related to indirect waterwithdrawal from the use of grid electricity and raw materials throughout the product life cycle. Approximately half of life cycle water withdrawal is associated with module manufacturing, one-third from balance of systems (BOS), and the remainder from takeback and recycling. Primary contributors to life cycle water withdrawal are the use of grid electricity, glass, and on-site water during manufacturing; steel, copper, inverters, and on-site water in the BOS; and electricity, chemical use, and transport during takeback and recycling. During manufacturing, water consumption is approximately one quarter of withdrawal and is due to cooling tower water evaporation and site irrigation. When deployed in the U.S. Southwest, a CdTe PV array can provide net displacement of life cycle water withdrawal of over 1700–5600 L/MWh relative to grid electricity.","PeriodicalId":6420,"journal":{"name":"2012 IEEE 38th Photovoltaic Specialists Conference (PVSC) PART 2","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90668196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-10-26DOI: 10.4229/27THEUPVSEC2012-3CV.2.37
D. Jawarani, Dewei Xu, Scott Smith, R. Rao, L. Mathew, S. Saha, D. Sarkar, S. Banerjee, P. Ho
Thin crystalline silicon solar cells are of interest due to significant material cost reduction and potentially high conversion efficiency. We have previously demonstrated a patented, novel exfoliation technology capable of producing large area (156×156 mm) 25 µm thin flexible mono c-Si cells with high efficiencies. In this paper we address the mechanical strength and handling requirements of these foils during wafer transfer, cell processing and module integration. Based on a bi-material foil composed of thin monocrystalline silicon and a supporting substrate fabricated using our novel SOM® (Semiconductor on Metal) kerf-less exfoliation process, closed-form mechanical analyses are introduced and developed to evaluate their strength and fracture behaviors. These analyses include the thermal stresses in the composite films and the effect of surface texturing on the fracture behavior of silicon in these foils. Functional cells were fabricated and module reliability results that include thermal shock and highly accelerated stress tests (HAST) are also shown in this paper.
{"title":"Integration and reliability of ultra thin silicon solar cells and modules fabricated using SOM® technology","authors":"D. Jawarani, Dewei Xu, Scott Smith, R. Rao, L. Mathew, S. Saha, D. Sarkar, S. Banerjee, P. Ho","doi":"10.4229/27THEUPVSEC2012-3CV.2.37","DOIUrl":"https://doi.org/10.4229/27THEUPVSEC2012-3CV.2.37","url":null,"abstract":"Thin crystalline silicon solar cells are of interest due to significant material cost reduction and potentially high conversion efficiency. We have previously demonstrated a patented, novel exfoliation technology capable of producing large area (156×156 mm) 25 µm thin flexible mono c-Si cells with high efficiencies. In this paper we address the mechanical strength and handling requirements of these foils during wafer transfer, cell processing and module integration. Based on a bi-material foil composed of thin monocrystalline silicon and a supporting substrate fabricated using our novel SOM® (Semiconductor on Metal) kerf-less exfoliation process, closed-form mechanical analyses are introduced and developed to evaluate their strength and fracture behaviors. These analyses include the thermal stresses in the composite films and the effect of surface texturing on the fracture behavior of silicon in these foils. Functional cells were fabricated and module reliability results that include thermal shock and highly accelerated stress tests (HAST) are also shown in this paper.","PeriodicalId":6420,"journal":{"name":"2012 IEEE 38th Photovoltaic Specialists Conference (PVSC) PART 2","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82670694","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-10-26DOI: 10.4229/27THEUPVSEC2012-4BV.4.50
G. Yordanov, O. Midtgård, T. O. Saetre, Henrik Kofoed Nielsen, L. Norum
Contrary to intuition, solar irradiance peaks at partially cloudy conditions. Clouds can boost sunlight by over 1.5 times, even at high latitudes. Depending on cloud velocity, the bursts last from seconds to minutes. Measuring irradiance on a tilted surface with 10-ms resolution allows for a detailed study of such events in Southern Norway, almost at sea level. All monthly maxima from April through September 2011 exceeded 1300 W/m2. The slow sensor registered an annual maximum of 1413 W/m2, while the fast sensor's range was found insufficient. A burst reaching 1528 W/m2 was registered in June 2012. Near the Equator, bursts exceeding 1800 W/m2 have been observed. These numbers are striking since the extraterrestrial solar irradiance peaks in January at about 1400 W/m2. The phenomenon is attributed mainly to forward scattering of light in optically thin clouds (adjacent to the sun), which is much stronger for angles within 5° around the solar disk.
{"title":"Overirradiance (cloud enhancement) events at high latitudes","authors":"G. Yordanov, O. Midtgård, T. O. Saetre, Henrik Kofoed Nielsen, L. Norum","doi":"10.4229/27THEUPVSEC2012-4BV.4.50","DOIUrl":"https://doi.org/10.4229/27THEUPVSEC2012-4BV.4.50","url":null,"abstract":"Contrary to intuition, solar irradiance peaks at partially cloudy conditions. Clouds can boost sunlight by over 1.5 times, even at high latitudes. Depending on cloud velocity, the bursts last from seconds to minutes. Measuring irradiance on a tilted surface with 10-ms resolution allows for a detailed study of such events in Southern Norway, almost at sea level. All monthly maxima from April through September 2011 exceeded 1300 W/m2. The slow sensor registered an annual maximum of 1413 W/m2, while the fast sensor's range was found insufficient. A burst reaching 1528 W/m2 was registered in June 2012. Near the Equator, bursts exceeding 1800 W/m2 have been observed. These numbers are striking since the extraterrestrial solar irradiance peaks in January at about 1400 W/m2. The phenomenon is attributed mainly to forward scattering of light in optically thin clouds (adjacent to the sun), which is much stronger for angles within 5° around the solar disk.","PeriodicalId":6420,"journal":{"name":"2012 IEEE 38th Photovoltaic Specialists Conference (PVSC) PART 2","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81605254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-06-03DOI: 10.1109/PVSC-VOL2.2012.6656709
J. Flicker, R. Kaplar, M. Marinella, J. Granata
In order to elucidate how the degradation of individual components affects the state of the photovoltaic inverter as a whole, we have carried out SPICE simulations to investigate the voltage and current ripple on the DC bus. The bus capacitor is generally considered to be among the least reliable components of the system, so we have simulated how the degradation of bus capacitors affects the AC ripple at the terminals of the PV module. Degradation-induced ripple leads to an increased degradation rate in a positive feedback cycle. Additionally, laboratory experiments are being carried out to ascertain the reliability of metallized thin film capacitors. By understanding the degradation mechanisms and their effects on the inverter as a system, steps can be made to more effectively replace marginal components with more reliable ones, increasing the lifetime and efficiency of the inverter and decreasing its cost per watt towards the US Department of Energy goals.
{"title":"PV inverter performance and reliability: What is the role of the bus capacitor?","authors":"J. Flicker, R. Kaplar, M. Marinella, J. Granata","doi":"10.1109/PVSC-VOL2.2012.6656709","DOIUrl":"https://doi.org/10.1109/PVSC-VOL2.2012.6656709","url":null,"abstract":"In order to elucidate how the degradation of individual components affects the state of the photovoltaic inverter as a whole, we have carried out SPICE simulations to investigate the voltage and current ripple on the DC bus. The bus capacitor is generally considered to be among the least reliable components of the system, so we have simulated how the degradation of bus capacitors affects the AC ripple at the terminals of the PV module. Degradation-induced ripple leads to an increased degradation rate in a positive feedback cycle. Additionally, laboratory experiments are being carried out to ascertain the reliability of metallized thin film capacitors. By understanding the degradation mechanisms and their effects on the inverter as a system, steps can be made to more effectively replace marginal components with more reliable ones, increasing the lifetime and efficiency of the inverter and decreasing its cost per watt towards the US Department of Energy goals.","PeriodicalId":6420,"journal":{"name":"2012 IEEE 38th Photovoltaic Specialists Conference (PVSC) PART 2","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88999196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-06-03DOI: 10.1109/PVSC-VOL2.2012.6750496
P. Espinet-González, C. Algora, V. Orlando, N. Núñez, M. Vázquez, J. Bautista, H. Xiugang, L. Barrutia, I. Rey‐Stolle, K. Araki
A quantitative temperature accelerated life test on sixty GaInP/GaInAs/Ge triple-junction commercial concentrator solar cells is being carried out. The final objective of this experiment is to evaluate the reliability, warranty period, and failure mechanism of high concentration solar cells in a moderate period of time. The acceleration of the degradation is realized by subjecting the solar cells at temperatures markedly higher than the nominal working temperature under a concentrator, while the photo-current nominal conditions are emulated by injecting current in darkness. Three experiments at three different temperatures are necessary in order to obtain the acceleration factor which relates the time at the stress level with the time at nominal working conditions. However, up to now only the test at the highest temperature has finished. Therefore, we can not provide complete reliability information but we have analyzed the life data and the failure mode of the solar cells inside the climatic chamber at the highest temperature. The failures have been all of them catastrophic. In fact, the solar cells have turned into short circuits. We have fitted the failure distribution to a two parameters Weibull function. The failures are wear-out type. We have observed that the busbar and the surrounding fingers are completely deteriorated.
{"title":"Preliminary temperature accelerated life test (ALT) on III-V commercial concentrator triple-junction solar cells","authors":"P. Espinet-González, C. Algora, V. Orlando, N. Núñez, M. Vázquez, J. Bautista, H. Xiugang, L. Barrutia, I. Rey‐Stolle, K. Araki","doi":"10.1109/PVSC-VOL2.2012.6750496","DOIUrl":"https://doi.org/10.1109/PVSC-VOL2.2012.6750496","url":null,"abstract":"A quantitative temperature accelerated life test on sixty GaInP/GaInAs/Ge triple-junction commercial concentrator solar cells is being carried out. The final objective of this experiment is to evaluate the reliability, warranty period, and failure mechanism of high concentration solar cells in a moderate period of time. The acceleration of the degradation is realized by subjecting the solar cells at temperatures markedly higher than the nominal working temperature under a concentrator, while the photo-current nominal conditions are emulated by injecting current in darkness. Three experiments at three different temperatures are necessary in order to obtain the acceleration factor which relates the time at the stress level with the time at nominal working conditions. However, up to now only the test at the highest temperature has finished. Therefore, we can not provide complete reliability information but we have analyzed the life data and the failure mode of the solar cells inside the climatic chamber at the highest temperature. The failures have been all of them catastrophic. In fact, the solar cells have turned into short circuits. We have fitted the failure distribution to a two parameters Weibull function. The failures are wear-out type. We have observed that the busbar and the surrounding fingers are completely deteriorated.","PeriodicalId":6420,"journal":{"name":"2012 IEEE 38th Photovoltaic Specialists Conference (PVSC) PART 2","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73771662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2012-06-03DOI: 10.1109/PVSC-VOL2.2012.6750498
A. Kolodziej, W. Baranowski, Michał Kołodziej, T. Kolodziej
Latest investigations in photovoltaic have generated interest in thin-film technologies with nanostructural modifications. In this paper we concentrate mainly on the technological experiments, as well as the structure and the composition control of the components of a thin silicon solar cell by means of electron microscopy as well as optical transmission and reflection analysis. Scattering and absorption from nanoparticles and their location within the multilayer solar cell are considered. Manufacturing Ag pellets with the desired shape and size makes the experiment even more difficult. The ZnO layers with relatively large Ag particles, exhibit favorable angle scattering leading to increased optical length and the layers with very small Ag particles (2.5 nm) located in the vicinity of the absorber show the excitation of surface plasmons increasing the absorption and influencing the frequency spectrum. We obtained a series of 5x5 cm2 samples with homogeneously distributed nano-crystalline Ag particles with high degree of control of nano-particle diameter size.
{"title":"The plasmonics front electrodes applied to thin film solar cells","authors":"A. Kolodziej, W. Baranowski, Michał Kołodziej, T. Kolodziej","doi":"10.1109/PVSC-VOL2.2012.6750498","DOIUrl":"https://doi.org/10.1109/PVSC-VOL2.2012.6750498","url":null,"abstract":"Latest investigations in photovoltaic have generated interest in thin-film technologies with nanostructural modifications. In this paper we concentrate mainly on the technological experiments, as well as the structure and the composition control of the components of a thin silicon solar cell by means of electron microscopy as well as optical transmission and reflection analysis. Scattering and absorption from nanoparticles and their location within the multilayer solar cell are considered. Manufacturing Ag pellets with the desired shape and size makes the experiment even more difficult. The ZnO layers with relatively large Ag particles, exhibit favorable angle scattering leading to increased optical length and the layers with very small Ag particles (2.5 nm) located in the vicinity of the absorber show the excitation of surface plasmons increasing the absorption and influencing the frequency spectrum. We obtained a series of 5x5 cm2 samples with homogeneously distributed nano-crystalline Ag particles with high degree of control of nano-particle diameter size.","PeriodicalId":6420,"journal":{"name":"2012 IEEE 38th Photovoltaic Specialists Conference (PVSC) PART 2","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75303994","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}