Hopman, S., Fell, A., Mayer, K., Mesec, M., Rodofili, A., Kray, D.
This paper deals with the development of a new cutting method for thin silicon solar wafers with liquid-jet-guided lasers (LaserMicroJetA (R), LMJ, and Laser Chemical Processing, LCP). Several laser...
Fell, A., Mayer, K., Hopman, S., Kray, D.
We present investigations on a new technology with which to cut wafers from it silicon ingot. i.e., the laser chemical processing (LCP), formerly known as laser chemical etching. A coupled...
Analysis of ultrathin high-efficiency silicon solar cells (2009)
In this paper we present experimental data on ultrathin silicon wafer solar cells as well as the analytical description of their open-circuit voltage and fill factor. For this we use the analytical...
Analysis of selective phosphorous laser doping in high-efficiency solar cells (2009)
This paper focuses on the analysis of local phosphorous laser doping in high-efficiency solar cells. Those so-called selective emitters are intended to reduce the contact recombination and resistance...
Laser chemical processing (LCP) - A versatile tool for microstructuring applications (2008)
Kray, D., Fell, A., Hopman, S., Mayer, K., Willeke, G.P., Glunz, S.W.
Laser Chemical Processing (LCP) is presented as a novel microstructuring method for multiple applications. Via the combination of a chemical liquid jet and a laser beam, thermochemical and...
Transient 3D/2D simulation of laser-induced ablation of silicon (2008)
Fell, A., Kray, D., Willeke, G.P.
A numerical software has been developed to simulate heating, enthalpy-based phase changes and ablation of silicon during pulsed or continuous-wave laser irradiation. The unsteady heat transfer...
Laser-doped silicon solar cells by laser chemical processing (LCP) exceeding 20% efficiency (2008)
Kray, D., Aleman, M., Fell, A., Hopman, S., Mayer, K., Mesec, M., ...
The introduction of selective emitters underneath the front contacts of solar cells can considerably increase the cell efficiency. Thus, cost-effective fabrication methods for this process step would...
Verfahren zum Materialabtrag an Festkoerpern und dessen Verwendung (2007)
Mayer, K., Baumann, S., Kray, D., Kolbesen, B.O.
WO 2007085454 A1 UPAB: 20070919 NOVELTY - A combined laser/fluid etching process applied to high-purity silicon wafer material. The fluid contains a halogen agent and removes liberated high-purity...
Verfahren und Vorrichtung zum Strukturieren einer Oberflaechenschicht (2007)
DE 102006003606 A1 UPAB: 20070924 NOVELTY - Method for structuring a surface layer (9) on a substrate (8) comprises guiding a liquid jet (6) directed onto the surface layer over the regions of the...
Verfahren und Vorrichtung zur lokalen Dotierung von Festkoerpern sowie dessen Verwendung (2007)
DE 102006003607 A1 UPAB: 20070927 NOVELTY - Method for localized doping of solid substrates, e.g. silicon substrates, comprises spraying the surface of the substrate with a stream of liquid...
Verfahren zum Materialabtrag an Festkoerpern und dessen Verwendung (2007)
Mayer, K., Kray, D., Kolbesen, B.O.
WO 2007085454 A1 UPAB: 20070919 NOVELTY - A combined laser/fluid etching process applied to high-purity silicon wafer material. The fluid contains a halogen agent and removes liberated high-purity...
Study on the edge isolation of industrial silicon solar cells with waterjet-guided laser (2007)
Kray, D., Hopman, S., Spiegel, A., Richerzhagen, B., Willeke, G.P.
Characterization of laser doped silicon wafers with laser chemical processing (2007)
Hopman, S., Fell, A., Mayer, K., Aleman, M., Mesec, M., Müller, R., ...
Verfahren zur Präzisionsbearbeitung von Substraten und dessen Verwendung (2007)
Mayer, K., Aleman, M., Kray, D., Glunz, S., Mette, A., Preu, R., ...
WO 2008107194 A2 UPAB: 20080930 NOVELTY - In a precision process to modify the microstructure of a thin layer for the local introduction of doping agents and local application of a seed layer, the...
Textur- und Reinigungsmedium zur Oberflaechenbehandlung von Wafern und dessen Verwendung (2007)
Mayer, K., Schumann, M., Kray, D., Orellana Peres, T., Rentsch, J., Zimmer, M., ...
DE 102007058829 A1 UPAB: 20090619 NOVELTY - A water-based texture- and cleaning agent is employed to treat the surface mono-crystalline wafers. The agent incorporates one or more alkaline etching...
Verfahren und Vorrichtung zur Bearbeitung von Waferoberflaechen (2007)
Mayer, K., Schumann, M., Kray, D., Orellana Peres, T., Rentsch, J., Zimmer, M.
DE 102007058876 A1 UPAB: 20090619 NOVELTY - Method for processing wafer surfaces comprises inserting wafers into a treatment chamber, contacting with an alkaline treatment solution containing a...
Strength characterization of laser diced silicon for application in solar industry (2006)
Schönfelder, S., Bagdahn, J., Baumann, S., Kray, D., Mayer, K., Willeke, G., ...
Laser technologies are used in a wide range of process steps in solar industry. In this paper novel laser dicing technologies like LaserMicroJet® and Laser Chemical Etching (LCE) are investigated...
Verfahren zur Mikrostrukturierung von Festkoerperoberflaechen (2006)
Mayer, K., Kray, D., Baumann, S., Kolbesen, B.O.
Die Erfindung betrifft ein Verfahren zur Mikrostrukturierung von Festkoerperoberflaechen durch chemisches oder elektrochemisches Aetzen, bei dem die Festkoerperoberflaeche mit einem Aetzfluid unter...
Solar wafer slicing with loose and fixed grains (2006)
Kray, D., Schumann, M., Eyer, A., Willeke, G.P., Kübler, J., Beinert, J., ...
In this Paper we investigate different process types for multi-wire sawing of so lar silicon wafers. These are the standard monodirectional wire movement as well as the reciprocating wire movement...
Investigation of laser-fired rear-side recombination properties using an analytical model (2006)
This paper presents the application of the analytical model for locally contacted rear sides recently published by Fischer to the determination of recombination losses of solar cells with fixed...
Experimental investigation of wire sawing thin multicrystalline wafers (2006)
Kray, D., Schumann, M., Schultz, O., Bergmann, M., Ettle, P., Rentsch, J., ...
Ätzverfahren zum Materialabtrag an Festkörpern und dessen Verwendung sowie Vorrichtung hierzu (2006)
Mayer, K., Kray, D., Bauman, S.
DE 102006019461 A1 UPAB: 20080208 NOVELTY - An etchant capable of being activated, is added to the liquid jet (1). It is activated after leaving the nozzle which produces the jet. Activation is...
Drahtsäge mit kontrollierbarem Drahtfeld (2006)
Bergmann, M., Ettle, P., Kray, D., Haas, F.
DE 102006033699 A1 UPAB: 20080131 NOVELTY - The wire saw has two cylindrical guide rollers (2a, 2b) arranged in parallel at a distance from each other. A wire (1) rotates the two guide rollers along...
DE 102006038001 B3 UPAB: 20080604 NOVELTY - The procedure for drying and/or dry holding of workpiece (4) during fluid jet guidance processing of the workpiece for cutting, micro structuring and...
High-efficiency multicrystalline silicon solar cells on gallium-doped substrate (2005)
Schultz, O., Glunz, S.W., Kray, D., Dhamrin, M., Yamaga, I., Saitoh, T., ...
Wafering research at Fraunhofer ISE (2005)
Kray, D., Baumann, S., Mayer, K., Schumann, M., Bando, M., Eyer, A., ...
Analysis of very thin high-efficiency solar cells (2003)
Kray, D., Leimenstoll, A., Glunz, S.W., Willeke, G.P., Kampwerth, H.
Progress in high-efficiency emitter-wrap-through cells on medium quality substrates (2003)
Kray, D., Dicker, J., Osswald, D., Leimenstoll, A., Glunz, S.W., Zimmermann, W., ...
High-efficiency silicon solar cells for low-illumination applications (2002)
Glunz, S.W., Dicker, J., Esterle, M., Hermle, M., Isenberg, J., Kamerewerd, F., ...
Huljic, D. M., Mäckel, H., Craff-Castillo, C., Kray, D., Ballif, C., Lüdemann, R.
Rapid Thermal Firing (RTF), i.e. firing of printed contacts by Rapid Thermal Processing, represents a promising alternative compared to firing in infrared heated conveyor belt furnaces. In this work...