Automating Advanced Packaging for 3D Structures with Micrometer Precision
- Shane Novacek
- 4 days ago
- 4 min read
Updated: 8 hours ago
eXtreme Fast Control (XFC) and EtherCAT accelerate contact-free printing technology in semiconductor manufacturing
Electronic components and their structures are becoming ever smaller, making it even more difficult to bond them. Conventional processes have long since reached their limits in this area, but the Impulse Printing™ process developed by Dutch start-up Fonontech offers something new: advanced packaging of semiconductors in 3D structures in the micrometer range. EtherCAT-enabled eXtreme Fast Control (XFC) technology components from Beckhoff are key in this process.
The miniaturization of electronic components makes it increasingly difficult for conventional lithography-based processes to economically and reliably produce the bonding structures between components. “Conventional manufacturing techniques are reaching the limits of what they can do. With our Impulse PrintingTM technology, we are taking things to the next level,” says Fabien Bruning, CTO of the Eindhoven, Netherlands-based Fonontech B.V.
The key parts in the process are silicon printing plates with micron-sized structures etched into them. These structures absorb the ink, which is then transferred to the printed circuit board substrates during the next step. Besides the etched conductor tracks, the printing plates also have a built-in heating system. Bruning explains, “A very high, short current pulse causes a tiny amount of the ink solvent to evaporate suddenly at the interface with the wafer. This blasts the ink off the wafer and onto the circuit board.” Rob Hendriks, CEO of Fonontech, adds, “This process works really well even at a distance of over 2 feet, albeit with less accuracy at that point.”
It is important that the printing process is fast and contact-free. A single current pulse can print thousands of lines on a circuit board or other substrate in less than 1 millisecond. The heating structures can be locally controlled to help align the structure being printed and the substrate. The print head developed by Fonontech covers an area of 128 x 128 mm and works with all common inks. “This allows 300 mm wafers or areas of 600 x 600 mm to be printed in a short space of time, a format that is currently finding its way into back-end semiconductor assembly,” says Bruning. With a flat heating plate and stencil printing, even larger structures can be produced in the same machine, such as flat screens. Several print heads can also be easily mounted side-by-side to cover larger structures.
Fast, precise performance with PC-based control
The entire process is automated with PC-based control from Beckhoff. “Working with EtherCAT and XFC technology, Fonontech can synchronize and position the various modules of the machine in real time and with the necessary precision,” explains Stijn de Bruin, sales engineer at Beckhoff Netherlands. When building the prototype, Fonontech’s Bruning decided to use as many standard components as possible. As he explains, he chose Beckhoff in part because of the flexibility that the TwinCAT 3 control software offers. “For example, we created algorithms in Simulink® that we execute in real time in TwinCAT.” He also adds that many third-party suppliers offer components that work with an EtherCAT interface.
EtherCAT is also accepted by SEMI™ (Semiconductor Equipment and Materials International) as a communication standard (E54.20). This has led Bruning to work on offering the print head as a separate module with an EtherCAT interface. “This would make it much easier for other companies in the semiconductor industry to integrate our technology into their machines.” Multiple print modules could also be combined to form a single large print head that uses EtherCAT distributed clocks and XFC to print larger structures with even higher precision.
Fonontech is currently using a C6017 ultra-compact Industrial PC that runs TwinCAT 3 PLC/NC PTP, TwinCAT 3 Target for Simulink®, and TwinCAT 3 HMI. The image processing application runs on a 19-inch C5240 slide-in Industrial PC. Bruning comments, “We could probably also run the algorithm on the C6017, but it’s more convenient for it to be installed on a separate industrial PC during development.”
The ultimate goal: 5 µm resolution
The prototype is currently printing multiple patterns measuring 10 µm in width on the substrates. “Structures as fine as these are beyond the abilities of most printing techniques,” explains Hendriks. Fonontech plans to go even further, aiming to produce lines just 5 µm wide with a sub-micrometer overlay error range. The exact timing needed for the high-precision processes is based on eXtreme Fast Control Technology from Beckhoff. The current motion concept will also need to be migrated to an air-bearing sub-micrometer platform. “Thanks to the openness and flexibility of PC-based control, this works with the same hardware and control philosophy,” says de Bruin from Beckhoff.
In the beta version of the system, different types of motors and a handling platform are integrated alongside the air-bearing system. The compact drive technology for low-voltages up to 48 V – the EL72xx EtherCAT Servomotor Terminals and AM8100 Servomotors – has the potential to save additional space and reduce costs during installation and commissioning. Bruning sees even more possibilities with the integration of distributed controllers and EtherCAT functionality. “There are not actually many alternatives to PC-based control on the market if you want to develop and market functional units with their own high-performance distributed controller and integrated motion.”
Fonotech’s Impulse Printing™ technology is changing the game for semiconductor packaging with 3D structures produced faster and more accurately than ever before. Beckhoff’s flexible PC-based control and EtherCAT connectivity have prepared the system to meet the complex demands of next-generation electronics. As the company continues pushing towards 5 µm, high-precision, adaptable semiconductor production is finally within reach.
Ready to push the limits of your semiconductor production with micrometer precision and EtherCAT-enabled XFC technology? Contact your local Beckhoff sales engineer today.
Shane Novacek is the Marketing Communications Manager at Beckhoff Automation