Arnold Gruppe has introduced a new squaring saw for monocrystalline brick production that is claims to be extremely robust. The type 72/746 squaring saw will be introduced at EU PVSEC in Hamburg, Germany. The type 72/746 squaring saw employs two diamond cutting discs working in parallel that are claimed to reduce kerf loss and increase throughput.
Monocrystalline wafers offer higher cell efficiencies but have been characterized by higher costs that multicrystalline wafers. Reducing mono-wafer processing costs is a key goal for mono-wafers competiveness. Replacing conventional saws with diamond cutting discs could eliminate slurry uses and significantly reduce kerf loss. Greater sawing control, maximizing brick production yields would also reduce costs.
The type 72/746 squaring saw employs two diamond cutting discs working in parallel (diameter 700mm), simultaneously process two sides of a brick in one step. The work piece must be turned only once by 90° in order to process the opposite side. This shortens the processing time and improves throughput. The flexible clamping concept offers the possibility to either crop the ingot before the squaring process or to do this process after the squaring is completed. One raw ingot with a maximum length of 3000mm or up to five individually cropped ingot pieces with a length between 180mm up to maximum of 1000mm can be processed in one step by making use of the total loading length. This is an important feature because the machine can be loaded in an optimal way. Arnold squaring technology does not require additional preparatory and subsequent work, e.g. glueing to ingot holder. All parts can be placed directly into the machine. By using the specially developed thin-blade technology with a blade thickness of 1.5mm, compared with the blade thicknesses commercially available of 3.5mm, silicon losses are claimed to be more than halved. Pitch can be easily adjusted to required production dimension. Diamond-blade technology does not require additional cutting additives, such as slurry, further reducing material costs. Tooling costs compared to wire saws are claimed to be only a tenth of the operating cost for the squaring saw.
Monocrystalline brick sawing for volume production.
The system is controlled by the Arnold Remote Production Analysis Tool (ARPAT), according to SEMI E10 standard and includes the speed, torque of cutting spindle and other information. This guarantees a closed-loop-process optimization. ARPAT disposes of an open interface to the supervisory MES (Manufacturing Execution System).
September 2011 onwards.