Inductive charging makes cleanroom automation by Fabmatics maintenance-free and safe

Thanks to advanced safety technology, mobile robots and employees move safely and efficiently side by side even in narrow cleanroom areas. (Source: Fabmatics GmbH, Photographer: Sven Claus (FotograFisch))

The mobile HERO Fab 200 positions a wafer carrier millimeter precisely in a cleanroom rack – an example of reliable material handling in established 200mm factories. (Source: Fabmatics GmbH, Photographer: Sven Claus (FotograFisch))

The Wiferion charging panel is integrated flush into the cleanroom floor slab – for contactless charging without particle generation and minimally invasive installation. (Source: Fabmatics GmbH, Photographer: Sven Claus (FotograFisch))

Charging in progress: The mobile robot charges energy via a charging panel in front of the handling station and continues working without separate charging breaks. (Source: Fabmatics GmbH, Photographer: Sven Claus (FotograFisch))

The global demand for power electronics and chips for applications in automotive, communication, and industrial sectors continues to grow unabated. However, many of the production facilities originate from a different era: 200-mm wafer factories built in the 1990s and 2000s are still operating today with partly manual material flows. Modernizing them is complex due to high purity requirements but is urgently needed. The Dresden automation specialist Fabmatics has been developing solutions for over 30 years, covering everything from transportation and storage to wafer identification – supported by the maintenance-free charging technology from Wiferion.

In the semiconductor industry, two fundamental wafer diameters are significant: 200 mm and 300 mm. 300-mm wafers are used to produce high-performance processors and memory chips and are manufactured in modern, highly automated factories. In contrast, the production equipment for 200-mm wafers, mainly used for power electronics and certain automotive components, is generally older and has grown organically over decades. The consequence: often, there are heterogeneous infrastructures that are difficult to reconcile with new technologies. At the same time, societal and economic pressures to automate processes are increasing. Supply chain bottlenecks, rising energy costs, and skilled labor shortages have demonstrated how important stable and seamless workflows are. Automation in semiconductor manufacturing is therefore no longer a future topic but a prerequisite for competitiveness.

In the heart of the European microelectronics cluster Dresden, Fabmatics, with more than 300 employees, ensures that 200-mm factories can operate their systems more efficiently and safely through customized automation solutions. The company supplies renowned customers in the international semiconductor industry in Europe, Asia, and the USA. As early as 2009, Fabmatics began developing its own mobile robot, initially tethered. The system was later developed to move freely in space, offering maximum flexibility for material transport. Today, transport robots like the HERO Fab are a fixed part of the product family. They autonomously transport wafer cassettes, connect machines across multiple levels, and can be optimally adapted to customer-specific layouts thanks to their modular design. One initial challenge was the power supply – until Fabmatics adopted the charging solution from Wiferion – a PULS brand.

Particle-free means inductive: Charging in the cleanroom

Since mobile robots in cleanrooms must generally be charged within the controlled, dust-free production environment, traditional charging systems quickly reach their limits. Removing the vehicles would significantly increase contamination risks and endanger entire batches of sensitive wafers. But charging within the cleanroom itself is also problematic with conventional contact technology: slip contacts and connectors generate abrasion particles during contact – an unacceptable risk in production environments where even tiny contaminants can cause damages worth millions. Copper, used in many contact solutions, is also taboo in cleanrooms because it can damage the surfaces of semiconductor substrates. Alternative materials like stainless steel or silver also proved ineffective in practice. "We wanted to offer our robots with an inductive charging solution right from the first generation, which launched in 2013, but the energy transfer capacity of those early systems was insufficient for our needs. Wiferion didn’t exist back then," says Carsten Grunert, Head of Product Development at Fabmatics. "So, we developed a contact-based charging technology integrated into the floor. However, this led to high wear and maintenance requirements and was not very flexible."

When Fabmatics developed the second generation of its mobile robots, the technological situation had fundamentally changed. Wiferion was now on the market and offered, as the first provider, an inductive charging solution capable of transmitting up to 60 amperes – enough to operate mobile robots in the cleanroom without interruption. This made possible what was technically impossible in 2013.

Together with partner PohlCon, Fabmatics developed charging pads that can be seamlessly embedded into the cleanroom’s double floor. Only one of the existing floor panels in the cleanroom needs to be replaced, avoiding costly renovations. Energy transfer occurs contactlessly via a magnetic field, generating no particles. Furthermore, the wireless charging system from the wireless charging specialist also offers fire protection advantages. Towing chains or open contacts that could produce particle abrasion and sparks are rendered unnecessary.

Flexible, maintenance-free, and future-proof: automated charging in the process

The greatest advantage, however, lies in the principle of in-process charging. Instead of scheduling fixed charging times, Fabmatics’ robots recharge during their normal work, such as during wafer cassette loading and unloading. Thanks to the high positioning tolerance of Wiferion systems, it is sufficient for the robot to briefly hover over the charging pad. Even small deviations do not cause charging interruptions. Every short pause is enough to keep the energy level stable. Separate charging zones, long breaks, or manual interventions are unnecessary. This also makes the solution particularly space-saving.

In addition to the minimally invasive installation, the charging system impresses with its high flexibility: thanks to its modular design, the charging infrastructure can be adapted to changing layouts – a significant advantage in mature production environments that are regularly expanded or reconfigured. This results in a maintenance-free charging infrastructure that integrates seamlessly into any existing production environment and scores points not only with cleanroom suitability but also with future security.

No towing chains or tripping hazards: new application areas

"The combination of wireless energy supply and process-integrated charging is ideal for our applications," explains Carsten Grunert. "We could already achieve 24/7 operation before – but today, it’s much more flexible, maintenance-free, and with the highest process purity. A real benefit for our systems! The high flexibility has also enabled us to explore new application areas."

Fabmatics has since integrated Wiferion technology into additional robot series previously limited by the constraints of conventional charging systems. Since the charging plates can also be mounted vertically on walls, they are suitable for vertical applications such as floor lifts. Especially for material transport across multiple floors, the technology offers advantages: without the need for mechanical connections or towing chains – which typically involve cables for energy transfer – potential tripping hazards and fire risks are eliminated. Additionally, the wireless solution allows for quiet, seamless integration into ongoing operations.

Conclusion: A major gain for automation in the semiconductor industry

By integrating Wiferion technology, Fabmatics has overcome a key hurdle in automating cleanroom processes. The inductive energy supply enables maintenance-free, process-integrated operation of mobile robots even in highly sensitive production environments. For the semiconductor industry, especially for 200-mm wafer factories with their historically grown structures, this represents a significant efficiency leap. Inductive charging thus becomes a key enabler for the next level of automation.