MNT - Grup de Recerca en Micro i Nanotecnologies
http://hdl.handle.net/2117/411
2024-03-29T14:13:44Z
2024-03-29T14:13:44Z
Substrate temperature optimization of pulsed-laser-deposited and in-situ Zn-supplemented-CZTS films and their integration into photovoltaic devices
Elhmaidi, Zakaria Oulad
Saucedo Silva, Edgardo Ademar
Abd-Lefdil, Mohammed
El Khakani, My Ali
http://hdl.handle.net/2117/371933
2024-02-02T01:30:12Z
2022-08-29T12:31:44Z
Substrate temperature optimization of pulsed-laser-deposited and in-situ Zn-supplemented-CZTS films and their integration into photovoltaic devices
Elhmaidi, Zakaria Oulad; Saucedo Silva, Edgardo Ademar; Abd-Lefdil, Mohammed; El Khakani, My Ali
The pulsed laser deposition (PLD) technique was used to deposit CZTS thin films onto SLG/Mo substrates via the KrF-laser ablation of a composite target consisting of Cu2ZnSnS4 pellet onto which Zn strips were purposely affixed. The effect of the substrate temperature (Tsub) of the PLD-CZTS films on their structure and properties was systematically studied over the 25–500 °C temperature range. The Zn content of the films was found to increase mainly when Tsub is raised from 300 to 500 °C. While both XRD and Raman analyses confirmed that the films consist of the kësterite-single-phase of which crystallinity improves when Tsub is increased (from RT up to 400 °C), the near resonant Raman (at 325 nm) revealed the presence of ZnS phase at high Tsub (> 400 °C). The optical energy band gap (Eg) of the PLD-CZTS films was consistently found to decrease from 1.9 to 1.4 eV when Tsub is increased from RT to 500 °C. Our results pointed out the Tsub = 400 °C as the optimal deposition temperature that meets at best the properties required for the PLD-CZTS films for PV application. The post-annealing (in presence of S and Sn vapors at 560 °C) of the PLD-CZTS films has improved further their crystallinity and led to the formation of some ZnS secondary phase at their surface. By appropriately integrating these post-annealed films into SLG/Mo/CZTS/CdS/ZnO/ITO photovoltaic devices, we were able to demonstrate their photoconversion ability with a PCE of 3.3 % (Voc = 512 mV, Jsc = 12.5 mA/cm2 and a FF = 51.5 %). The analysis of their EQE spectrum suggests that the effective carrier collection length in the CZTS absorption layer needs to be extended further to achieve higher photoconversion efficiencies.
2022-08-29T12:31:44Z
Elhmaidi, Zakaria Oulad
Saucedo Silva, Edgardo Ademar
Abd-Lefdil, Mohammed
El Khakani, My Ali
The pulsed laser deposition (PLD) technique was used to deposit CZTS thin films onto SLG/Mo substrates via the KrF-laser ablation of a composite target consisting of Cu2ZnSnS4 pellet onto which Zn strips were purposely affixed. The effect of the substrate temperature (Tsub) of the PLD-CZTS films on their structure and properties was systematically studied over the 25–500 °C temperature range. The Zn content of the films was found to increase mainly when Tsub is raised from 300 to 500 °C. While both XRD and Raman analyses confirmed that the films consist of the kësterite-single-phase of which crystallinity improves when Tsub is increased (from RT up to 400 °C), the near resonant Raman (at 325 nm) revealed the presence of ZnS phase at high Tsub (> 400 °C). The optical energy band gap (Eg) of the PLD-CZTS films was consistently found to decrease from 1.9 to 1.4 eV when Tsub is increased from RT to 500 °C. Our results pointed out the Tsub = 400 °C as the optimal deposition temperature that meets at best the properties required for the PLD-CZTS films for PV application. The post-annealing (in presence of S and Sn vapors at 560 °C) of the PLD-CZTS films has improved further their crystallinity and led to the formation of some ZnS secondary phase at their surface. By appropriately integrating these post-annealed films into SLG/Mo/CZTS/CdS/ZnO/ITO photovoltaic devices, we were able to demonstrate their photoconversion ability with a PCE of 3.3 % (Voc = 512 mV, Jsc = 12.5 mA/cm2 and a FF = 51.5 %). The analysis of their EQE spectrum suggests that the effective carrier collection length in the CZTS absorption layer needs to be extended further to achieve higher photoconversion efficiencies.
Chapter 4: intelligent fault diagnosis of photovoltaic systems
Chouder, Aissa
Silvestre Bergés, Santiago
http://hdl.handle.net/2117/371580
2022-07-29T10:20:19Z
2022-07-29T10:17:57Z
Chapter 4: intelligent fault diagnosis of photovoltaic systems
Chouder, Aissa; Silvestre Bergés, Santiago
Photovoltaic (PV) systems operating in real conditions of work are very often subject to several faults that may lower significantly the produced energy and shorten their availability. Therefore, powerful and trusted fault detection procedures are necessary to enable early maintenance and avoid excessive energy losses. The large increase in PV power installed worldwide in recent years, especially in systems connected to electricity distribution networks: Grid-connected PV systems, has led to the development of strategies and tools for automatic supervision of these systems to detect faults and diagnose the source of these failures. This chapter presents a review of most relevant existing methodologies applied in fault detection and diagnosis of PV systems.
2022-07-29T10:17:57Z
Chouder, Aissa
Silvestre Bergés, Santiago
Photovoltaic (PV) systems operating in real conditions of work are very often subject to several faults that may lower significantly the produced energy and shorten their availability. Therefore, powerful and trusted fault detection procedures are necessary to enable early maintenance and avoid excessive energy losses. The large increase in PV power installed worldwide in recent years, especially in systems connected to electricity distribution networks: Grid-connected PV systems, has led to the development of strategies and tools for automatic supervision of these systems to detect faults and diagnose the source of these failures. This chapter presents a review of most relevant existing methodologies applied in fault detection and diagnosis of PV systems.
Bromine etching of kesterite thin films: perspectives in depth defect profiling and device performance improvement
Tiwari, Kunal Jogendra
Jiménez Arguijo, Alex
Giraldo, Sergio
Placidi, Marcel Jose
Calvo-Barrio, L
Fonoll Rubio, Robert
Izquierdo Roca, Víctor
Sánchez González, Yudania
Perez Rodriguez, Alejandro
Saucedo Silva, Edgardo Ademar
Jehl Li-Kao, Zacharie
http://hdl.handle.net/2117/371557
2024-03-10T03:42:24Z
2022-07-29T07:26:10Z
Bromine etching of kesterite thin films: perspectives in depth defect profiling and device performance improvement
Tiwari, Kunal Jogendra; Jiménez Arguijo, Alex; Giraldo, Sergio; Placidi, Marcel Jose; Calvo-Barrio, L; Fonoll Rubio, Robert; Izquierdo Roca, Víctor; Sánchez González, Yudania; Perez Rodriguez, Alejandro; Saucedo Silva, Edgardo Ademar; Jehl Li-Kao, Zacharie
Using a controlled bromine etching on kesterite absorbers, two major results are obtained. We establish the first defect depth profiling and secondary phases depth profiling of a state of the art Cu2ZnSnSe4 (CZTSe) film by using surface sensitive characterization methods (XPS and Raman spectroscopy) on successively etched samples, obtaining a direct insight on the factors hampering the performance of this class of absorber. In a second step, we demonstrate the possibility of significant improvement to the p-n interface in Cu2ZnGeSe4 (CZGSe)/CdS solar cells when a short bromine etching of the absorber is performed, with the Fill Factor improving by more than 7 points. This method offers a simple improvement pathway for state of the art kesterite devices, with a potentially broader application to thin film solar cells where the p-n interface is limiting.
2022-07-29T07:26:10Z
Tiwari, Kunal Jogendra
Jiménez Arguijo, Alex
Giraldo, Sergio
Placidi, Marcel Jose
Calvo-Barrio, L
Fonoll Rubio, Robert
Izquierdo Roca, Víctor
Sánchez González, Yudania
Perez Rodriguez, Alejandro
Saucedo Silva, Edgardo Ademar
Jehl Li-Kao, Zacharie
Using a controlled bromine etching on kesterite absorbers, two major results are obtained. We establish the first defect depth profiling and secondary phases depth profiling of a state of the art Cu2ZnSnSe4 (CZTSe) film by using surface sensitive characterization methods (XPS and Raman spectroscopy) on successively etched samples, obtaining a direct insight on the factors hampering the performance of this class of absorber. In a second step, we demonstrate the possibility of significant improvement to the p-n interface in Cu2ZnGeSe4 (CZGSe)/CdS solar cells when a short bromine etching of the absorber is performed, with the Fill Factor improving by more than 7 points. This method offers a simple improvement pathway for state of the art kesterite devices, with a potentially broader application to thin film solar cells where the p-n interface is limiting.
Synergetic effect induced/tuned bimetallic nanoparticles (Pt-Ni) anchored graphene as a catalyst for oxygen reduction reaction and scalable SS-314L serpentine flow field proton exchange membrane fuel cells (PEMFCs)
Velayutham, Rajavel
Palanisamy, Karthikeyan
Manikandan, Ramu
Velumani, Thiagarajan
Kumar AP, Senthil
Puigdollers i González, Joaquim
Chul Kim, Byung
http://hdl.handle.net/2117/371075
2022-07-31T17:49:30Z
2022-07-26T07:51:56Z
Synergetic effect induced/tuned bimetallic nanoparticles (Pt-Ni) anchored graphene as a catalyst for oxygen reduction reaction and scalable SS-314L serpentine flow field proton exchange membrane fuel cells (PEMFCs)
Velayutham, Rajavel; Palanisamy, Karthikeyan; Manikandan, Ramu; Velumani, Thiagarajan; Kumar AP, Senthil; Puigdollers i González, Joaquim; Chul Kim, Byung
A simple design of electroactive and cost-effective electrocatalysts for oxygen reduction reaction (ORR) activity is crucial towards energy conversion in the commercialization of proton exchange membrane fuel cells (PEMFCs). Herein, we synthesized a stable electroactive bimetallic catalyst of Ni anchored with low loading of Pt nanoparticles, and graphene used as a supportive material for catalyst integration (Pt3-Ni/G). It exhibited maximum electrochemical surface area (ECSA, 108.56 m2/gPt), mass activity (2.2 A mgPt) and specific activity (3.47 mA cm-2), signifying an excellent ORR activity. In addition, a scalable PEMFC fabrication through 0.2 mgPtcm-2 Pt3-Ni/G as cathode with an active area of 25 cm2 and stainless steel-314L (SS-314L) used as a serpentine flow field. This strategy provides a maximum power output of 71.25 W mgPt-1 at current density 1.59 A cm-2. In addition, Pt3-Ni/C//Pt/C, based PEMFC system delivered a constant power output (68.75 W mgPt-1) even after 4 h of continuous cycling.
© 2022 Elsevier. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/
2022-07-26T07:51:56Z
Velayutham, Rajavel
Palanisamy, Karthikeyan
Manikandan, Ramu
Velumani, Thiagarajan
Kumar AP, Senthil
Puigdollers i González, Joaquim
Chul Kim, Byung
A simple design of electroactive and cost-effective electrocatalysts for oxygen reduction reaction (ORR) activity is crucial towards energy conversion in the commercialization of proton exchange membrane fuel cells (PEMFCs). Herein, we synthesized a stable electroactive bimetallic catalyst of Ni anchored with low loading of Pt nanoparticles, and graphene used as a supportive material for catalyst integration (Pt3-Ni/G). It exhibited maximum electrochemical surface area (ECSA, 108.56 m2/gPt), mass activity (2.2 A mgPt) and specific activity (3.47 mA cm-2), signifying an excellent ORR activity. In addition, a scalable PEMFC fabrication through 0.2 mgPtcm-2 Pt3-Ni/G as cathode with an active area of 25 cm2 and stainless steel-314L (SS-314L) used as a serpentine flow field. This strategy provides a maximum power output of 71.25 W mgPt-1 at current density 1.59 A cm-2. In addition, Pt3-Ni/C//Pt/C, based PEMFC system delivered a constant power output (68.75 W mgPt-1) even after 4 h of continuous cycling.
Life cycle assessment of different chalcogenide thin-film solar cells
Resalati, Shahaboddin
Okoroafor, Tobechi
Maalouf, Amani
Saucedo Silva, Edgardo Ademar
Placidi, Marcel Jose
http://hdl.handle.net/2117/370823
2022-07-24T15:52:18Z
2022-07-21T11:29:21Z
Life cycle assessment of different chalcogenide thin-film solar cells
Resalati, Shahaboddin; Okoroafor, Tobechi; Maalouf, Amani; Saucedo Silva, Edgardo Ademar; Placidi, Marcel Jose
Thin-film photovoltaics (PV) cells offer several benefits over conventional first-generation PV technologies, including lighter weight, flexibility, and lower power generation cost. Among the competing thin-film technologies, chalcogenide solar cells offer promising performance on efficiency and technological maturity level. However, in order to appraise the performance of the technology thoroughly, issues such as raw materials scarcity, toxicity, and environmental impacts need to be investigated in detail. This paper therefore, for the first time, presents a cradle to gate life cycle assessment for four different emerging chalcogenide PV cells, and compares their results with copper zinc tin sulfide (CZTS) and the commercially available CIGS to examine their effectiveness in reducing the environmental impacts associated with PV technologies. To allow for a full range of indicators, life cycle assessment methods CML 2001, IMPACT 2002+, and ILCD 2011 were used to analyse the results. The results identify environmental hotspots associated with different materials and components and demonstrate that using current efficiencies, the environmental impact of copper indium gallium selenide (CIGS) for generating 1kWh electricity was lower than that of the other studied cells. However, at comparable efficiencies the antimony-based cells offered the lowest environmental impacts in all impact categories. The effect of materials used was also found to be lower than the impact of electricity consumed throughout the manufacturing process, with the absorber layer contributing the most to the majority of the impact categories examined. In terms of chemicals consumed, cadmium acetate contributed significantly to the majority of the environmental impacts. Stainless steel in the substrate/insulating layer and molybdenum in the back contact both contributed considerably to the toxicity and ozone depletion impact categories. This paper demonstrates considerable environmental benefits associated with non-toxic chalcogenide PV cells suggesting that the current environmental concerns can be addressed effectively using alternative materials and manufacturing techniques if current efficiencies are improved.
2022-07-21T11:29:21Z
Resalati, Shahaboddin
Okoroafor, Tobechi
Maalouf, Amani
Saucedo Silva, Edgardo Ademar
Placidi, Marcel Jose
Thin-film photovoltaics (PV) cells offer several benefits over conventional first-generation PV technologies, including lighter weight, flexibility, and lower power generation cost. Among the competing thin-film technologies, chalcogenide solar cells offer promising performance on efficiency and technological maturity level. However, in order to appraise the performance of the technology thoroughly, issues such as raw materials scarcity, toxicity, and environmental impacts need to be investigated in detail. This paper therefore, for the first time, presents a cradle to gate life cycle assessment for four different emerging chalcogenide PV cells, and compares their results with copper zinc tin sulfide (CZTS) and the commercially available CIGS to examine their effectiveness in reducing the environmental impacts associated with PV technologies. To allow for a full range of indicators, life cycle assessment methods CML 2001, IMPACT 2002+, and ILCD 2011 were used to analyse the results. The results identify environmental hotspots associated with different materials and components and demonstrate that using current efficiencies, the environmental impact of copper indium gallium selenide (CIGS) for generating 1kWh electricity was lower than that of the other studied cells. However, at comparable efficiencies the antimony-based cells offered the lowest environmental impacts in all impact categories. The effect of materials used was also found to be lower than the impact of electricity consumed throughout the manufacturing process, with the absorber layer contributing the most to the majority of the impact categories examined. In terms of chemicals consumed, cadmium acetate contributed significantly to the majority of the environmental impacts. Stainless steel in the substrate/insulating layer and molybdenum in the back contact both contributed considerably to the toxicity and ozone depletion impact categories. This paper demonstrates considerable environmental benefits associated with non-toxic chalcogenide PV cells suggesting that the current environmental concerns can be addressed effectively using alternative materials and manufacturing techniques if current efficiencies are improved.
Study of PV systems for self-consumption at the UPC based on simulations by using PVSol
Silvestre Bergés, Santiago
http://hdl.handle.net/2117/370695
2022-07-20T10:40:18Z
2022-07-20T10:38:15Z
Study of PV systems for self-consumption at the UPC based on simulations by using PVSol
Silvestre Bergés, Santiago
The aim of this work is to carry out a sustainability study in five campuses of the Universitat Politècnica de Catalunya BarcelonaTech (UPC) around Catalunya, i.e. Campus North and South Campuses in Barcelona city, Campus Baix Llobregat, Campus Manresa and Campus Vilanova i la Geltrú. The amount of consumed energy included in the study for each campus corresponds to monitoring data of previous periods. The study analyses the expected energy production, as well as the self-consumption that can be achieved by using photovoltaic (PV) systems of 25, 50 and 100 kWp and c-Si, Poly or CdTe Technology in order to reduce the environmental impact in each campus. An economic analysis of all the proposed facilities was conducted to examine their financial feasibility.
2022-07-20T10:38:15Z
Silvestre Bergés, Santiago
The aim of this work is to carry out a sustainability study in five campuses of the Universitat Politècnica de Catalunya BarcelonaTech (UPC) around Catalunya, i.e. Campus North and South Campuses in Barcelona city, Campus Baix Llobregat, Campus Manresa and Campus Vilanova i la Geltrú. The amount of consumed energy included in the study for each campus corresponds to monitoring data of previous periods. The study analyses the expected energy production, as well as the self-consumption that can be achieved by using photovoltaic (PV) systems of 25, 50 and 100 kWp and c-Si, Poly or CdTe Technology in order to reduce the environmental impact in each campus. An economic analysis of all the proposed facilities was conducted to examine their financial feasibility.
Acceleration and drift reduction of MOX gas sensors using active sigma-delta controls based on dielectric excitation
Solà Peñafiel, Nil
Manyosa i Vilardell, Xavier
Navarrete Gatell, Eric
Ramos Castro, Juan José
Jiménez Serres, Vicente
Bermejo Broto, Sandra
García, Isabel
Llobet Valero, Eduard
Domínguez Pumar, Manuel
http://hdl.handle.net/2117/370143
2023-07-02T09:13:22Z
2022-07-13T11:16:51Z
Acceleration and drift reduction of MOX gas sensors using active sigma-delta controls based on dielectric excitation
Solà Peñafiel, Nil; Manyosa i Vilardell, Xavier; Navarrete Gatell, Eric; Ramos Castro, Juan José; Jiménez Serres, Vicente; Bermejo Broto, Sandra; García, Isabel; Llobet Valero, Eduard; Domínguez Pumar, Manuel
The objective of this paper is to apply a closed-loop control based on dielectric excitation to MOX gas sensors in order to improve their response time. The control implements a feedback loop in which temperature modulations keep constant the sensor reactance, measured at constant temperature. The required fast temperature switching has been implemented on MEMS microhotplates. The mean temperature generated by the control is the new output signal. This technique is applied to an in-house sensor made of WO3 nanowires decorated with gold nanoparticles to detect NH3 and to a commercial MEMS MOX sensor (CCS801).
2022-07-13T11:16:51Z
Solà Peñafiel, Nil
Manyosa i Vilardell, Xavier
Navarrete Gatell, Eric
Ramos Castro, Juan José
Jiménez Serres, Vicente
Bermejo Broto, Sandra
García, Isabel
Llobet Valero, Eduard
Domínguez Pumar, Manuel
The objective of this paper is to apply a closed-loop control based on dielectric excitation to MOX gas sensors in order to improve their response time. The control implements a feedback loop in which temperature modulations keep constant the sensor reactance, measured at constant temperature. The required fast temperature switching has been implemented on MEMS microhotplates. The mean temperature generated by the control is the new output signal. This technique is applied to an in-house sensor made of WO3 nanowires decorated with gold nanoparticles to detect NH3 and to a commercial MEMS MOX sensor (CCS801).
Towards low cost and sustainable thin film thermoelectric devices based on quaternary chalcogenides
Isotta, Eleonora
Andrade Arvizu, Jacob
Syafiq, Ubaidah
Jiménez Arguijo, Alex
Navarro Güell, Alejandro
Guc, Maxim
Saucedo Silva, Edgardo Ademar
Scardi, Paolo
http://hdl.handle.net/2117/369719
2023-10-20T07:45:33Z
2022-07-06T11:16:57Z
Towards low cost and sustainable thin film thermoelectric devices based on quaternary chalcogenides
Isotta, Eleonora; Andrade Arvizu, Jacob; Syafiq, Ubaidah; Jiménez Arguijo, Alex; Navarro Güell, Alejandro; Guc, Maxim; Saucedo Silva, Edgardo Ademar; Scardi, Paolo
A major challenge in thermoelectrics (TEs) is developing devices made of sustainable, abundant, and non-toxic materials. Furthermore, the technological drive toward low sizes makes crucial the study of nano and micro configurations. In this work, thin film TE devices based on p-type Cu2+xZn1-xSnS4 and Cu2+xZn1-xSnSe4, and n-type AlyZn1-yO are fabricated by physical vapor deposition. The kesterite phases show good purity and promising TE power factor, likely enhanced by the copper–zinc order–disorder transition. Thin film generators in planar configuration are assembled by a sequential deposition of the p-type, n-type, and contact materials. The power per unit planar area reaches 153 and 279 nW cm-2 for the sulphur- and selenium-based generators, respectively. These values significantly outperform any other literature attempt based on sustainable and low-cost thin films. Furthermore, if compared with traditional TEs often made of scarce and toxic materials, these devices offer a cost reduction above 80%. This allows reaching comparable values of power density per unit material cost, representing a first real step toward the development of sustainable and non-toxic thin film TE devices. These can find applications in micro energy harvesters, microelectronics coolers, and temperature controllers for wearables, medical appliances, and sensors for the internet of things.
This is the peer reviewed version of the following article: Isotta, E. [et al.]. Towards low cost and sustainable thin film thermoelectric devices based on quaternary chalcogenides. "ADVANCED FUNCTIONAL MATERIALS", 20 Maig 2022, núm. 2202157, which has been published in final form at https://onlinelibrary.wiley.com/doi/10.1002/adfm.202202157. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley’s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited.
2022-07-06T11:16:57Z
Isotta, Eleonora
Andrade Arvizu, Jacob
Syafiq, Ubaidah
Jiménez Arguijo, Alex
Navarro Güell, Alejandro
Guc, Maxim
Saucedo Silva, Edgardo Ademar
Scardi, Paolo
A major challenge in thermoelectrics (TEs) is developing devices made of sustainable, abundant, and non-toxic materials. Furthermore, the technological drive toward low sizes makes crucial the study of nano and micro configurations. In this work, thin film TE devices based on p-type Cu2+xZn1-xSnS4 and Cu2+xZn1-xSnSe4, and n-type AlyZn1-yO are fabricated by physical vapor deposition. The kesterite phases show good purity and promising TE power factor, likely enhanced by the copper–zinc order–disorder transition. Thin film generators in planar configuration are assembled by a sequential deposition of the p-type, n-type, and contact materials. The power per unit planar area reaches 153 and 279 nW cm-2 for the sulphur- and selenium-based generators, respectively. These values significantly outperform any other literature attempt based on sustainable and low-cost thin films. Furthermore, if compared with traditional TEs often made of scarce and toxic materials, these devices offer a cost reduction above 80%. This allows reaching comparable values of power density per unit material cost, representing a first real step toward the development of sustainable and non-toxic thin film TE devices. These can find applications in micro energy harvesters, microelectronics coolers, and temperature controllers for wearables, medical appliances, and sensors for the internet of things.
N-type doping of SiC-passivated Ge by pulsed laser melting towards the development of interdigitated back contact thermophotovoltaic devices
Jiménez Pagán, Alba
Napolitani, Enrico
Datas Medina, Alejandro
Martín García, Isidro
López Rodríguez, Gema
Cabrero Piris, Mariona
Sgarbossa, Francesco
Milazzo, Ruggero
Carturan, Sara Maria
De Salvador, Davide
López García, Iñaki
Ryu, Yu Kyoung
Martinez Rodrigo, Javier
del Cañizo Nadal, Carlos
http://hdl.handle.net/2117/367008
2024-03-03T20:51:52Z
2022-05-06T12:29:17Z
N-type doping of SiC-passivated Ge by pulsed laser melting towards the development of interdigitated back contact thermophotovoltaic devices
Jiménez Pagán, Alba; Napolitani, Enrico; Datas Medina, Alejandro; Martín García, Isidro; López Rodríguez, Gema; Cabrero Piris, Mariona; Sgarbossa, Francesco; Milazzo, Ruggero; Carturan, Sara Maria; De Salvador, Davide; López García, Iñaki; Ryu, Yu Kyoung; Martinez Rodrigo, Javier; del Cañizo Nadal, Carlos
In this article, a method for phosphorous (n-type) doping of germanium based on spin-on dopant sources and Pulsed Laser Melting (PLM) throughout an amorphous silicon carbide (a-SixC1-x:H) layer, which provides both surface passivation and electrical isolation, has been demonstrated, paving the way towards the development of Ge-based interdigitated back contact thermophotovoltaic devices. This method offers simultaneous opening of the a-SixC1-x:H layer and creation of a heavily doped region underneath without using photolithographic steps, eventually enabling a low-cost and scalable manufacturing process. This article focuses on the optimization of the n+/p junction formation by studying the effect of different laser energy fluences and number of pulses on the diffusion profiles measured by secondary ion mass spectrometry, and on the electrical performance characterized by Van der Pauw-Hall technique. Additionally, the crystalline quality after PLM has been analyzed by Rutherford backscattering measurements in channeling conditions, high-resolution X-Ray diffraction and transmission electron microscopy. High level of donor activation (up to 1·1019 cm- 3 ), low sheet resistance (˜50 O/¿), and high mobility (275–700 cm2 /V·s) have been obtained, with a weaker dependency of these parameters on the explored laser energy fluence range. A prototype diode has been developed demonstrating a rectifying behavior but with high saturation current densities. Point-like contact formation will be implemented in future works to reduce the laser irradiated area, and thus, improve the surface passivation and device characteristics.
© 2022 Elsevier. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/
2022-05-06T12:29:17Z
Jiménez Pagán, Alba
Napolitani, Enrico
Datas Medina, Alejandro
Martín García, Isidro
López Rodríguez, Gema
Cabrero Piris, Mariona
Sgarbossa, Francesco
Milazzo, Ruggero
Carturan, Sara Maria
De Salvador, Davide
López García, Iñaki
Ryu, Yu Kyoung
Martinez Rodrigo, Javier
del Cañizo Nadal, Carlos
In this article, a method for phosphorous (n-type) doping of germanium based on spin-on dopant sources and Pulsed Laser Melting (PLM) throughout an amorphous silicon carbide (a-SixC1-x:H) layer, which provides both surface passivation and electrical isolation, has been demonstrated, paving the way towards the development of Ge-based interdigitated back contact thermophotovoltaic devices. This method offers simultaneous opening of the a-SixC1-x:H layer and creation of a heavily doped region underneath without using photolithographic steps, eventually enabling a low-cost and scalable manufacturing process. This article focuses on the optimization of the n+/p junction formation by studying the effect of different laser energy fluences and number of pulses on the diffusion profiles measured by secondary ion mass spectrometry, and on the electrical performance characterized by Van der Pauw-Hall technique. Additionally, the crystalline quality after PLM has been analyzed by Rutherford backscattering measurements in channeling conditions, high-resolution X-Ray diffraction and transmission electron microscopy. High level of donor activation (up to 1·1019 cm- 3 ), low sheet resistance (˜50 O/¿), and high mobility (275–700 cm2 /V·s) have been obtained, with a weaker dependency of these parameters on the explored laser energy fluence range. A prototype diode has been developed demonstrating a rectifying behavior but with high saturation current densities. Point-like contact formation will be implemented in future works to reduce the laser irradiated area, and thus, improve the surface passivation and device characteristics.
Controlling the anionic ratio and gradient in kesterite technology
Andrade Arvizu, Jacob
Fonoll Rubio, Robert
Izquierdo Roca, Víctor
Becerril Romero, Ignacio
Sylla, Dioulde Huguette
Vidal Fuentes, Pedro
Jehl Li-Kao, Zacharie
Thomere, Angélica
Giraldo, Sergio
Tiwari, Kunal Jogendra
Resalati, Shahaboddin
Guc, Maxim
Placidi, Marcel Jose
http://hdl.handle.net/2117/366863
2024-03-10T08:54:24Z
2022-05-05T11:04:39Z
Controlling the anionic ratio and gradient in kesterite technology
Andrade Arvizu, Jacob; Fonoll Rubio, Robert; Izquierdo Roca, Víctor; Becerril Romero, Ignacio; Sylla, Dioulde Huguette; Vidal Fuentes, Pedro; Jehl Li-Kao, Zacharie; Thomere, Angélica; Giraldo, Sergio; Tiwari, Kunal Jogendra; Resalati, Shahaboddin; Guc, Maxim; Placidi, Marcel Jose
Accurate anionic control during the formation of chalcogenide solid solutions is fundamental for tuning the physicochemical properties of this class of materials. Compositional grading is the key aspect of band gap engineering and is especially valuable at the device interfaces for an optimum band alignment, for controlling interface defects and recombination and for optimizing the formation of carrier-selective contacts. However, a simple and reliable technique that allows standardizing anionic compositional profiles is currently missing for kesterites and the feasibility of achieving a compositional gradient remains a challenging task. This work aims at addressing these issues by a simple and innovative technique. It basically consists of first preparing a pure sulfide absorber with a specific thickness followed by the synthesis of a pure selenide part of complementary thickness on top of it. Specifically, the technique is applied to the synthesis of Cu2ZnSn(S,Se)4 and Cu2ZnGe(S,Se)4 kesterite absorbers, and a series of characterizations are performed to understand the anionic redistribution within the absorbers. For identical processing conditions, different Se incorporation dynamics is identified for Sn- and Ge-based kesterites, leading to a homogeneous or graded composition in depth. It is first demonstrated that for Sn-based kesterite the anionic composition can be perfectly controlled through the thicknesses ratio of the sulfide and selenide absorber parts. Then, it is demonstrated that for Ge-based kesterite an anionic (Se–S) gradient is obtained and that by adjusting the processing conditions the composition at the back side can be finely tuned. This technique represents an innovative approach that will help to improve the compositional reproducibility and determine a band gap grading strategy pathway for kesterites. Furthermore, due to its simplicity and reliability, the proposed methodology could be extended to other chalcogenide materials.
2022-05-05T11:04:39Z
Andrade Arvizu, Jacob
Fonoll Rubio, Robert
Izquierdo Roca, Víctor
Becerril Romero, Ignacio
Sylla, Dioulde Huguette
Vidal Fuentes, Pedro
Jehl Li-Kao, Zacharie
Thomere, Angélica
Giraldo, Sergio
Tiwari, Kunal Jogendra
Resalati, Shahaboddin
Guc, Maxim
Placidi, Marcel Jose
Accurate anionic control during the formation of chalcogenide solid solutions is fundamental for tuning the physicochemical properties of this class of materials. Compositional grading is the key aspect of band gap engineering and is especially valuable at the device interfaces for an optimum band alignment, for controlling interface defects and recombination and for optimizing the formation of carrier-selective contacts. However, a simple and reliable technique that allows standardizing anionic compositional profiles is currently missing for kesterites and the feasibility of achieving a compositional gradient remains a challenging task. This work aims at addressing these issues by a simple and innovative technique. It basically consists of first preparing a pure sulfide absorber with a specific thickness followed by the synthesis of a pure selenide part of complementary thickness on top of it. Specifically, the technique is applied to the synthesis of Cu2ZnSn(S,Se)4 and Cu2ZnGe(S,Se)4 kesterite absorbers, and a series of characterizations are performed to understand the anionic redistribution within the absorbers. For identical processing conditions, different Se incorporation dynamics is identified for Sn- and Ge-based kesterites, leading to a homogeneous or graded composition in depth. It is first demonstrated that for Sn-based kesterite the anionic composition can be perfectly controlled through the thicknesses ratio of the sulfide and selenide absorber parts. Then, it is demonstrated that for Ge-based kesterite an anionic (Se–S) gradient is obtained and that by adjusting the processing conditions the composition at the back side can be finely tuned. This technique represents an innovative approach that will help to improve the compositional reproducibility and determine a band gap grading strategy pathway for kesterites. Furthermore, due to its simplicity and reliability, the proposed methodology could be extended to other chalcogenide materials.