Inline condensation soldering with vacuum
The CondensoX-Line has brought a system to market that enables vacuum condensation soldering processes to be easily integrated into standard SMD lines. This allows void-free solder joints to be manufactured in a completely inert process environment (<100ppm O2), whether they are standard modules with BGA devices or DCB substrates for power electronics.
By building a 3-chamber system, low cycle times can be achieved for inert soldering processes. The first chamber already provides a protective atmosphere of nitrogen for the products before they are transported into the actual soldering process. The second, vacuum-compatible process chamber can be purged with nitrogen or forming gases and offers an inert or activating and void-reducing process atmosphere throughout the soldering process. In addition, here formic acid can optionally be used for flux-free processing – a novelty in the world of vapour phase soldering. The final gas-tight cooling chamber provides for controlled and rapid cooling of the assemblies by means of adjustable convection with less than 100 ppm residual oxygen in the atmosphere.
With the advantages of the inline condensation soldering process, a high throughput, and the creation of an inert atmosphere in the entire system, the CondensoX-Line meets the highest demands of mass production in the power electronics.
Unique technological Advantages
- Ideal for the processing of massive assemblies (IGBT, Heatsinks) down to sensitive sub-modules (01005, 03015)
- Reliable condensation soldering process for SMD manufacturing in a continuous process
- Horizontal transport of the modules of the entire process
- Inert process atmosphere during the entire soldering process for increased reliability of the assembly
- Cooling section can be used with <100ppm residual oxygen, ideal for subsequent bonding processes and surfaces to be protected against oxidation
- Void-free soldering with the use of vacuum for best results
- Significantly higher throughput when compared with stand-alone systems or batch systems, thanks to the multi-chamber structure
- Easy line integration
- Best traceability of soldering processes
A patented principle for reliable, void-free solder joints
Condensation or vapor phase soldering makes use of heat released during the transition from the vaporous to the liquid state in order to heat up the PCB to be soldered. Temperature remains continuously constant during the medium’s change of state (phase transition). As a result, the maximum temperature of the PCB cannot exceed the boiling point of the medium (Galden®), or its condensation temperature.
The soldering process takes place in a sealed process chamber. The vapor allows for extremely effective heat transfer to the PCBs due to the release of heat during condensation. In addition to this, the medium’s boiling point limits the maximum soldering temperature so that the PCBs cannot, under any circumstances, be damaged due to overheating.
As a unique feature in the field of condensation soldering, the handling systems included with the CondensoX series can be subsequently adapted according to the customer’s needs. And thus the basic system grows along with your requirements without forcing you to invest in a completely new system. You simply replace the loading system and are thus provided with optimized production equipment utilization.
Pre-chamber
The pre-chamber of the CondensoX-Line is hermetically sealed and can be flushed with nitrogen. This provides an optimal atmosphere and leads to a reliable soldering process. This pre-inertisation increases the reliability of the solder joint by prevention of the oxidation of the mico-structure parameters.
Process chamber
A defined quantity of an inert fluid (usually perfluorpolyether) is vaporized during reflow soldering in the process chamber, which is hermetically sealed by means of a bulkhead. The vapor allows for extremely effective heat transfer to the PCBs due to the release of heat during condensation, and the temperature of the medium remains constant. In addition to this, the medium’s boiling point limits the maximum soldering temperature so that the PCBs cannot be damaged due to overheating. This, as well as the ability to control the volume of injected liquid and intermediate exhaust of the vapor, also makes it possible to precisely adjust the temperature/reflow profile of the PCB. Flawlessly reproducible soldering results are thus guaranteed, which minimizes scrap rates.
Cooling chamber
After the soldering process the PCB‘s are cooled down in the cooling chamber. With a nozzle field the cold process gas (eg. N2) flows to the PCB‘s. Then, the process gas is cooled by water cooler and fed back into the process. The cooling process takes place in an inert atmosphere at a value of ≤ 100 ppm of residual oxygen, thus protecting copper for subsequent bonding processes.
Medium recycling
The exhaustet Galden is filtered and impurities are removed. Afterwards the cleaned fluid is placed at the disposal for further soldering processes in a tank. Due to the fact that the process chamber is hermetically sealed, only minimal loss results from vaporization during the soldering process. Medium consumption, as well as costs, are thus significantly reduced
Advantages for your manufacturing process:
- Fluid filtering and Recycling
- Minimal loss results from vaporization in the process chamber
- Drastic reduction of fluid consumption
- Environmental friendly
Loading/Unloading
The transport of the PCB’s in the CondensoX-Line is worked out throughout the entire process by a workpiece carrier, which are moved to the respective positions required for the process. For loading of the workpiece carrier, the PCB’s are sequentially pushed by a pusher from the peripheral device to the predefined positions on the workpiece carrier. Once the goods carrier is fully loaded, it is transported to the next process step. In parallel, the next workpiece carrier is already loaded, so that the process chain must not be interrupted. After the soldering process is completed the workpiece carrier is also discharged by a pusher and handed over to the empty workpiece carrier in the return transport and can then be loaded again
Safe and protected transport
The board carrier dimension is 650 x 650mm and varies at the height ( Version 1: 0 – 80 mm | Version 2: -20 – 65 mm). The workpiece carrier can be equipped with up to 6 lanes and has a fixed side-panel which serves as a starting point, as well as five adjustable crosspieces.
The assemblies are transported strictly horizontally through the soldering system. Furthermore, the PCB is stationary during the soldering process. In this way, components cannot be shifted out of place while the solder is molten. It has thus been possible to eliminate a considerable disadvantage associated with conventional vapour phase soldering systems within which continuous vertical motion of the PCBs is required during soldering. Scrap rates are reduced as a result, as well as costs.
Advantages at a glance
- Horizontal transport
- PCBs are still during the complete process
- High speed handling systems for high throughput
- Continuous inert process atmosphere
- Inline vacuum process
- Easy, accurate temperature profiling
Why vacuum?
Void-free soldering with lead-free solders is an important prerequisite for the production of power electronics. However, minimal void rates are only possible with soldering processes which subject the molten solder to a vacuum, making it easier for any remaining residues to escape from the solder joints. For this reason, the Condenso is equipped with a vacuum pump. This results in solder joints with surface contact ratios of up to 99 % in many cases.
In addition to the vacuum process during the melting phase, vacuum can also be applied before starting with the soldering process itself. This allows not only an uniformly distribution of the Galden vapour in the process room but the evaporation of the solvents of the paste. Furthermore, besides the temperature the atmosphere can be varied over the total residence time in the process chamber.
Optimized results thanks to vacuum!
There are lots of applications, for example in the field of component manufacturing for power electronics, in which low void rates are specified. However, such low void rates can only be realized with soldering processes by means of which the molten solder is subjected to a vacuum. This, as well, is no problem for the CondensoX product range – with just two additional steps: vacuum generation during the melting phase and an option for pre-vacuum prior to the actual soldering process, thus making it possible to achieve void-free solder joints in just five steps
Just 3 steps to the creation of a profile – and just 5 for vacuum!
Profiling can be so easy! With Rehm’s CondensoX you only have to complete three steps in order to create an ideal profile for your PCB. Furthermore, you’re provided with endless profiling options, allowing you to further refine and adapt your profile depending on the PCB and the specified requirements.
As a rule, however, the following 3 steps are enough to arrive at your goal – the ideal temperature profile for your application:
- Injection of the Galden® | preheating of the PCB
- Injection of the Galden® | ideal soldering temperature
- Exhaust of the Galden® | cooling of the PCB
Reliable, reproducible solder joints
During the first step, the PCBs are preheated by injecting the Galden® by means of our patented injection process. The ideal soldering temperature is then achieved by injecting additional Galden® during the second step. Subsequently, the medium is exhausted from the process chamber and the PCB is cooled down during the third step – finished! Profiling can’t be any easier than this!
The results are reliable, reproducible solder Joints!
Just 5 steps to vacuum!
Vacuum not only assures uniform injection of the Galden®, it also allows for outgassing of solvents from the solder paste. Vacuum during the melting phase makes it possible for gases still present in the solder paste to escape even better, thus providing for surface adhesion of greater than 98%.
- Pre-vacuum | uniform distribution of the Galden®
- Injection of the Galden® | preheating of the PCB
- Injection of the Galden® | ideal soldering temperature
- Vacuum during the melting phase | void-free solder joint
- Exhaust of the Galden® | cooling of the PCB
User-friendly software
Visu 2 includes process tools, remote maintenance and connection options for a barcode scanner. It features an intuitive user interface which considerably reduces the effort required for setup and operator training. Complete documentation can be accessed with just a few clicks. Visu 2 also provides password-protected administration with several access levels, language selection, data logging and maintenance reports.
WPS – Wireless Profiling
The wireless profiling system (WPS) is a temperature measuring system which can be used for wireless acquisition of the reflow profile without a separate power supply. Thermocouples and data loggers with tracking are thus rendered unnecessary. By means of the integrated evaluation unit and with the help of simple test PCBs, the temperature profile can be continuously monitored in an uncomplicated fashion and documented, e.g. for the substantiation of quality.
Additional Tools
- Comprehensive online documentation
- Multilingual software
- Data logging
- Import/export protocol
- Maintenance protocol
- Barcode interface
- Process disabling
- Remote maintenance