Solar cell process development in the european integrated project crystalclear

CrystalClear is a large integrated project funded by the European Commission that aims to drastically reduce the cost of crystalline Si PV modules, down to 1 Euro/Wp. Among the different subprojects, the one dealing with the development of advanced solar cells is relatively large (with 11 partners out of the 15 Crystal Clear partners taking part) and has a crucial role. The goal of the subproject is to develop cell design concepts and manufacturing processes that would enable a reduction in the order of 40% of the cell processing costs per Wp. In this paper, we give an overview of all the development work that has taken place in the CrystalClear solar cells subproject so far. World class results have been achieved, particularly on high efficiency cells on Si ribbons, and on industrial-type solar cells on very thin (120 (j.m thick) substrates

Evaluation of immunological escape mechanisms in a mouse model of colorectal liver metastases

<p>Abstract</p> <p>Background</p> <p>The local and systemic activation and regulation of the immune system by malignant cells during carcinogenesis is highly complex with involvement of the innate and acquired immune system. Despite the fact that malignant cells do have antigenic properties their immunogenic effects are minor suggesting tumor induced mechanisms to circumvent cancer immunosurveillance. The aim of this study is the analysis of tumor immune escape mechanisms in a colorectal liver metastases mouse model at different points in time during tumor growth.</p> <p>Methods</p> <p>CT26.WT murine colon carcinoma cells were injected intraportally in Balb/c mice after median laparotomy using a standardized injection technique. Metastatic tumor growth in the liver was examined by standard histological procedures at defined points in time during metastatic growth. Liver tissue with metastases was additionally analyzed for cytokines, T cell markers and Fas/Fas-L expression using immunohistochemistry, immunofluorescence and RT-PCR. Comparisons were performed by analysis of variance or paired and unpaired <it>t </it>test when appropriate.</p> <p>Results</p> <p>Intraportal injection of colon carcinoma cells resulted in a gradual and time dependent metastatic growth. T cells of regulatory phenotype (CD4+CD25+Foxp3+) which might play a role in protumoral immune response were found to infiltrate peritumoral tissue increasingly during carcinogenesis. Expression of cytokines IL-10, TGF-β and TNF-α were increased during tumor growth whereas IFN-γ showed a decrease of the expression from day 10 on following an initial increase. Moreover, liver metastases of murine colon carcinoma show an up-regulation of FAS-L on tumor cell surface with a decreased expression of FAS from day 10 on. CD8+ T cells express FAS and show an increased rate of apoptosis at perimetastatic location.</p> <p>Conclusions</p> <p>This study describes cellular and macromolecular changes contributing to immunological escape mechanisms during metastatic growth in a colorectal liver metastases mouse model simulating the situation in human cancer.</p

Pyramidal texturing of silicon solar cell with TMAH chemical anisotropic etching

International audienc

Impact of wafer quality on boron-diffused n-type bifacial solar cells

International audienceno abstrac

Impact of wafer quality on boron-diffused n-type bifacial solar cells

International audienceno abstrac

Industrial approaches of selective emitter on multicrystalline silicon solar cells

International audienc

Interdigitated Back Contacts Solar Cells on Transferred Si-Thin Film Epitaxially Grown on Porous Silicon

International audienceIn this paper we propose a novel approach to thin-film silicon solar cells technology developed at INSA-LYON, named ELIT process (Epitaxial Layer for Interdigitated back contacts solar cell Transferred using porous silicon as a weakened layer). High crystal quality Si film is grown on porous silicon (PS) by Vapor Phase Epitaxy. This single crystal silicon epitaxial layer was processed into solar cells by realizing all contacts on the back side. Then, thin film solar cell is transferred onto a low-cost substrate before texturation and deposition of antireflective coating on the front side. Preliminary experiments of transferred IBC thin-film solar cell lead to 7.7% efficiency with a 70 µm thick active layer

A review on 5 years cell development within the European integrated project Crystal Clear

CrystalClear is a large integrated project funded by the European Commission that aims to drastically reduce the cost of crystalline Si PV modules, down to 1 Euro/Wp. Among the different subprojects, the one dealing with the development of advanced solar cells is relatively large (with 11 partners out of the 15 Crystal Clear partners taking part) and has a crucial role. The goal of the subproject is to develop cell design concepts and manufacturing processes that would enable a reduction in the order of 40% of the cell processing costs per Wp. In this paper, we give an overview of all the development work that has taken place in the CrystalClear solar cells subproject so far. World class results have been achieved, particularly on high efficiency cells on Si ribbons, and on industrial-type solar cells on very thin (120 μm thick) substrates

A review on 5 years cell development within the european integrated project crystal clear

The integrated project (IP) Crystal Clear has been finalized in June 2009 and thus a chapter of more than 5 years successful collaboration between European solar cell research institutes and industry is closed. This paper reviews the achievements within the 4th subproject (SP4) of Crystal Clear dealing with the development of advanced solar cell concepts. Within SP4, 12 of the 16 partners have participated and have formed a productive consortium. The goal of this subproject was the further reduction of the cell production costs to enable the psychological important Si PV module price below 1 Euro/Watt. This should be reached by novel cell designs and manufacturing processes in order to achieve a process cost reduction of 40% (cost per Wp). One major effort was put in the development of novel cell concepts and processes suited for thin wafers in industrial fabrication. Three cell concepts were distinguished and developed by the participating institutes: i-PERC, MWT with full Al, and solar cells with laser fired contacts (PERC-LFC). In addition to the effort to implement these concepts into an industrial type of process with large area wafers, excellent results have been achieved on EFG and RGS ribbons. World record results with laboratory-type processes could be reported, with efficiencies of 18.2 % on EFG ribbons and 14.4 % on RGS ribbons. The defect mechanism of these materials has been studied in detail and efficiency limits have been indicated. The paper will refer to the separate contributions submitted to the conference by the different partners on specific topics