The new Fast Firing systems for typical monocrystalline and multicrystalline solar cell manufacturing are impressive thanks to their high quality and modular structure, which provides different line solutions. The Fast Firing systems by Rehm are available as pure Fast Firing systems RFS or with an integrated dryer as the RFS-D. The maintenance-friendly design of these systems, the low energy consumption, high throughput and intelligent software solutions characterise these high-quality systems for the metallisation line. All systems are fitted with short-wave IR radiators in upper and underside heating. The continuous process monitoring and visualisation guarantees maximum process quality. Rehm solar systems have been developed and manufactured to the highest quality standards, based on our decades of experience with thermal system solutions.
The Fast Firing system is cooled according to the principle of forced convection. A high-performance fan extracts the air from the process chamber and sends it through a filter system. The cold air is then sent back into the chamber onto the wafers again. The cooling capacity can be controlled via the intensity of the fans (speed regulation), as well as via the integrated water cooling system (cooling water circuit). This means that the optimum cooling gradient can always be set for the respective requirements. Like the process chamber, the cooling chamber can also be opened upwards using lifting gear, which ensures good accessibility for maintenance work.
The system provides a flexible transport system for a wide range of loading requirements. Different belt widths and belt types are available for this purpose. For operation with double-lane transport, a maximum throughput of 5300 wafers per hour is possible. All RFS belts can be supplied with a mount. Thanks to the optimum processing and the high-quality material of the belt, as well as guiding on quartz rods, low-vibration transport of the wafers is ensured. Thanks to the good resistance of nickel-chromium V at high temperatures, the conveyor unit does not have any problems maintaining the temperatures of up to 1000°C during the firing process and guarantees a long service life.
The separate belt systems between the firing zone and the cooling zone is another positive point. This ensures low heat transfer to the cooling zone and thus fast cooling of the wafers after the firing process. The outfeed temperature of the wafers with a separate belt is <40°C compared to a continuous belt, for which the temperature is significantly higher. Furthermore, the separate transport units reduce the energy consumption for wafer cooling by 2 kW, which allows savings to be made on operating costs.
In the drying process, smoke and vapors from the volatile components of the organic compounds (VOC) evaporate. These have to be removed from the process chamber in order to ensure constant conditions for subsequent processes and to produce high-quality solar cells. The integrated oxidiser transfers the VOC to water and carbon dioxide at high temperatures with a level of efficiency of up to 99.9% and ensures that the concentration of pollutants in the exhaust gas is kept very low in this process.
Smart software for your manufacturing
Would you like to reliably monitor, manage and document all processes? The Visu 2 includes process tools, remote control and barcode connection options. A simple ‘wafer counter’ system is possible, as is full connection to an MES system for the intelligent collection of operating and machine data. The Visu 2 has an intuitive user interface, which considerably reduces configuration and operator training costs. Extensive documentation can be retrieved in just a few clicks. The Visu 2 also offers password-protected administration with several levels, language selection, data display and maintenance logs.