Forschungsschwerpunkt "Nanostrukturierte Materialien"

Forschungsgebiet "Photovoltaik / Regenerative Energien"

The group focuses on solar cells that are based on chalcogenide thin films. Light absorbing layers of the type Cu(In,Ga)(Se,S)₂, Cu₂ZnSn(Se,S)₄ or other chalcogenides are combined in a thin film heterostructure similar as shown in Fig. 1. Research topics are:

Improving the efficiency of state-of-the-art solar cells, mainly Cu(In,Ga)(Se,S)₂

Understanding current efficiency limitations

Investigating process schemes for high productivity and low cost

Testing in-line and off-line process monitoring and quality assessment

Develop new heterostructure components, in particular absorber layers

Modelling of electronic transport

Fig. 1: Scanning electron micrograph of a Mo/Cu(In,Ga)Se₂/CdS/ZnO solar cell on glass in cross-section view. Thin layers of MoSe₂ (~10 nm) and CdS (~50 nm) are not visible in the micrograph. The working principle of heterostructure solar cells is simple: Due to the asymmetric contacts (CdS/ZnO on one side and Mo on the other side) electrons and holes being the charge carriers are flowing to opposite directions. They form the photo current which can drive an electrical load.

Thin film preparation in our group uses physical vapour deposition under vacuum – a technique that is also employed in commercial production. Different elemental vapours are directed to the heated substrate (Fig. 2). Insitu monitoring techniques such as laser light scattering give a real-time signal of the growing thin-film. Different substrate types can be used. In the system of Fig. 2 only the absorber layers such as Cu(In,Ga)Se₂ are prepared. Other deposition methods for the cell in Fig. 1 are sputtering (Mo, ZnO) and chemical bath deposition (CdS) which are performed in different set-ups. The thin MoSe₂ layer is a reaction product of the polycrystalline molybdenum film with the selenium atmosphere.

Fig. 2: Sketch of a physical vapour deposition system for the simultaneous evaporation of different elements. Typically non-crystalline substrates are used which lead to polycrystalline film growth. Epitaxial growth requires crystalline substrates and is only occasionally accomplished for research purposes.

Homepage der Fachgruppe Photovoltaik am Institut für Physik der Martin-Luther-Universität Halle-Wittenberg


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Home Koordination Beirat Dokumente Galerie Forschung aktuelle Forschungsgebiete: Oxidische Grenzflächen / Spintronik Nanostrukturierte Polymere Photovoltaik / Regenerative Energien frühere Forschungsgebiete Nachwuchsgruppen Aktuelles Chirale Elektronik: MLU überzeugt mit Forschungsskizze bei Exzellenzstrategie US-Akademie ehrt Stuart Parkin als Erfinder moderner Festplatten Max-Born-Preis 2024: Physikerin Ingrid Mertig für Verdienste um Spintronik geehrt ARCHIV RSS-Feed Beteiligte Einrichtungen Martin-Luther Universität Halle-Wittenberg Max-Planck-Institut für Mikrostrukturphysik Fraunhofer-Institut für Mikrostruktur von Werkstoffen und Systemen IMWS Fraunhofer-Center für Silizium-Photovoltaik CSP Forschungsverbünde / Drittmittelprojekte SFB/TRR 227 FOR 2811 SPP 2137 GRK 2670 SPEAR IMPRS BAT4EVER ZIK SiLi-nano ZIK HALOmem HYPOS Solarvalley Mitteldeutschland Kontakt Impressum/Satzung	Forschungsgebiet "Photovoltaik / Regenerative Energien" The group focuses on solar cells that are based on chalcogenide thin films. Light absorbing layers of the type Cu(In,Ga)(Se,S)₂, Cu₂ZnSn(Se,S)₄ or other chalcogenides are combined in a thin film heterostructure similar as shown in Fig. 1. Research topics are: Improving the efficiency of state-of-the-art solar cells, mainly Cu(In,Ga)(Se,S)₂ Understanding current efficiency limitations Investigating process schemes for high productivity and low cost Testing in-line and off-line process monitoring and quality assessment Develop new heterostructure components, in particular absorber layers Modelling of electronic transport Fig. 1: Scanning electron micrograph of a Mo/Cu(In,Ga)Se₂/CdS/ZnO solar cell on glass in cross-section view. Thin layers of MoSe₂ (~10 nm) and CdS (~50 nm) are not visible in the micrograph. The working principle of heterostructure solar cells is simple: Due to the asymmetric contacts (CdS/ZnO on one side and Mo on the other side) electrons and holes being the charge carriers are flowing to opposite directions. They form the photo current which can drive an electrical load. Thin film preparation in our group uses physical vapour deposition under vacuum – a technique that is also employed in commercial production. Different elemental vapours are directed to the heated substrate (Fig. 2). Insitu monitoring techniques such as laser light scattering give a real-time signal of the growing thin-film. Different substrate types can be used. In the system of Fig. 2 only the absorber layers such as Cu(In,Ga)Se₂ are prepared. Other deposition methods for the cell in Fig. 1 are sputtering (Mo, ZnO) and chemical bath deposition (CdS) which are performed in different set-ups. The thin MoSe₂ layer is a reaction product of the polycrystalline molybdenum film with the selenium atmosphere. Fig. 2: Sketch of a physical vapour deposition system for the simultaneous evaporation of different elements. Typically non-crystalline substrates are used which lead to polycrystalline film growth. Epitaxial growth requires crystalline substrates and is only occasionally accomplished for research purposes. Homepage der Fachgruppe Photovoltaik am Institut für Physik der Martin-Luther-Universität Halle-Wittenberg Last modified: March 19, 2013 14:04 (letzte Änderung: 19.03.2013, 14:04 Uhr)