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Publications (3)0 Total impact

  • Conference Proceeding: Large Area Screen Printed N-Type Silicon Solar Cells with Rear Aluminium Emitter: Efficiencies Exceeding 16%
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    ABSTRACT: We present low cost, screen printed industrial solar cells with a rear Al-emitter for n-type mono- and mc-Si large area thin wafers showing efficiencies of 16.4% and 14.4% respectively. The gap of 2% absolute between the cell efficiencies for mono- and mc-Si is not material related but is largely due to the non-textured surface of the mc-Si substrate. Applying a surface texture by acidic wet chemical etching could lead to efficiencies above 15% on the mc-Si material. The process is based on the standard industrial p-type firing through solar cell concept with slight modifications in individual processing steps similar to the Phostop cell presented by Ebara Solar. There is still need for further optimisation before industrialisation for instance in the fields of wafer bowing reduction and the implementation of AgAl pads for wafer interconnection. We propose two different ways of pad printing-one directly to the Al-emitter, the other on top of the Al rear contact
    Photovoltaic Energy Conversion, Conference Record of the 2006 IEEE 4th World Conference on; 06/2006
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    Conference Proceeding: Large Area Screen Printed N-Type MC-SI Solar cells With B-Emitter: Efficiencies Close to 15% and Innovative Module Interconnection
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    ABSTRACT: In this paper we present n-type Si solar cells on large area mc-Si wafers with a boron diffused emitter at the front side. The focus of our studies is mainly related to the front surface of the solar cell. We have optimised BBr<sub>3</sub>-diffusion and in-situ oxidation with respect to the homogeneity of the sheet resistance and substrate degradation. After diffusion even a slight improvement of the minority charge carrier lifetime was measured, which can be related to B-gettering. The emitter is contacted by AgAl-paste and passivated by thermal SiO<sub>2</sub>. The development and optimisation of all processes led to solar cells with efficiencies of 14.7% on mc-Si and 17.1% on Cz-Si substrates. In addition to this we present an innovative interconnection of modules using our developed cell (patent pending). We show an alternate serial interconnection of p- and n-type solar cells resulting in easier module processing
    Photovoltaic Energy Conversion, Conference Record of the 2006 IEEE 4th World Conference on; 06/2006
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    Article: Technical experience during thermal and chemical recycling of a 23 year old PV generator formerly installed on Pellworm island
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    ABSTRACT: The disassembly of the 23 year old PV generator formerly installed on Pellworm Island offers the sel-dom opportunity to recycle a large amount of PV modules of the same design. The technical experience obtained dur-ing this recycling process is presented. The high quantity of nearly identical modules allows to investigate, to record and to evaluate the different types of damage of the modules and the recycling process systematically. The influence of module design and module damage on the results of the whole process as well as of several process steps like thermal and chemical treatment is described.