Tripled throughput in OLED material development

In the race to develop next-generation display technologies, one of the biggest challenges is creating and validating new materials. OTI Lumionics from Canada is accelerating this time-consuming process with automation technology from Beckhoff. Through increased efficiency in test production, the company is now able to complete the validation process for its high-end OLED materials more quickly.

“We're developing breakthrough materials by design, using quantum simulations, machine learning, and real-world testing in pilot production,” says Michael Helander, CEO and President of OTI Lumionics, located in Mississauga, Ontario. These materials will enable breakthrough features in a range of electronics – from smartphones with under-display cameras to state-of-the-art automotive displays. “Working closely with partners like Apple, Samsung, and LG, we're creating the key enabling materials for next-generation OLED displays in consumer electronics and automotive applications,” Helander adds.

Test process under scrutiny

To enable this kind of success, OTI created EPOC-auto, their innovative material testing platform for pilot production. “Before developing EPOC-auto, we were struggling with different results from different operators," said Terry Xu, VP Engineering at OTI Lumionics. “It was difficult to repeat the same OLED structure and thus to fine-tune some critical parameters. The systems were mostly idle because the device structure must be completed in one run during the day. As a result, the operating cost of these tools was very high, while the yield of working OLED samples was low.”

Automating the process required overcoming a complex set of challenges. The system needed to handle 20 substrates with completely different layer structures automatically while maintaining movement accuracy of 0.1 mm for substrate and mask alignment – a level of material deposition control that would be difficult even in a single operation, let alone sustained across continuous testing cycles. In addition, the system needed to control multiple material sources simultaneously, each requiring its own precision controller for managing deposition rates at nanometer scale. To get consistent results, hundreds of sensors and moving elements had to work in perfect coordination.

Adding to the complexity, the system also needed to adapt to changing experimental requirements.
“Because of the experimental nature of our business, our objectives can vary daily,” explained Terry Yang, Senior Mechatronics Engineer. “And this means we needed a system that could be adjusted and upgraded at a rapid pace.”

Industrial automation in a scientific environment

To address these challenges, OTI made the decision to standardize on the universal PC-based control platform from Beckhoff. At the heart of the solution is the CX2033 Embedded PC, which manages the entire automated testing process while providing the precise, deterministic control needed for nanometer-scale material deposition. This is complemented by the real-time EtherCAT industrial Ethernet system for seamless integration of sensors, actuators, and scientific instruments.

The broad spectrum of EtherCAT Terminals enables communication with third-party devices and helps to bridge the gap between scientific instruments and automation. The flexibility these interfaces provided for integration, was crucial given the unique requirements of semiconductor research and development.

EtherCAT integrates scientific instruments

OTI leveraged EL6021 serial interface terminals, which provide RS422/RS485 communication at up to 115.2 kbaud, to enable high-speed data exchange with specialized equipment like quartz crystal microbalances and vacuum controllers. EL3024 4-channel analog input terminals, meanwhile, deliver 12-bit resolution with electrical isolation, providing accurate monitoring of multiple deposition parameters simultaneously while protecting sensitive measurement equipment. The EL3318 8-channel thermocouple input terminals enable precise temperature monitoring across multiple thermal zones with built-in linearization and cold junction compensation.

This combination creates a robust measurement and control infrastructure that maintains accuracy down to the nanometer scale required for OLED material development. The terminals' compact design and direct EtherCAT implementation throughout the system also simplify cabinet design while providing the flexibility to add interfaces for new measurement points as testing requirements evolved.

Building on this streamlined architecture, the motion control system integrates Terminals for precise positioning control with AM8122 servomotors. “The One Cable Technology for the compact servomotors makes wiring clean, while the serial communication libraries allow easy integration of third-party components,” Terry Yang explains.

During the implementation, OTI worked closely with Rui Zhang, P.Eng., Application Engineer & Drive Technology Products Specialist at Beckhoff Canada, who assisted with integrating the AM8122 servomotors and software configuration in particular. The motion control system also incorporates five AX5201 servo drives that, together with the motors, form the critical interface between the mechanical system and the control system. With current control cycles as fast as 62.5 μs, they deliver the required performance for highly dynamic positioning tasks.

OTI benefits from the flexible feedback interface of the AX5000 series, which supports connections with various feedback systems, including resolvers and high-resolution encoders. This flexibility, combined with the drives' variable parameterization capabilities for current and speed filters allowed the engineering team to fine-tune the motion control for the nanometer-precision requirements.

“OTI's strong technical foundation and experience with object-oriented programming principles made the integration process exceptionally smooth,” Rui Zhang says. The system leverages TwinCAT automation software, which integrates real-time control with PLC, NC, and CNC functionality on a single platform. The software's engineering environment enables configuration, programming, debugging, and diagnostics of all connected automation devices. “We exclusively use Structured Text because of its close resemblance to object-oriented programming,” notes Terry Yang. “This makes our software easy to read and debug because of the concise programming style.”

From complexity to clarity

“EPOC-auto can run 24/7 with minimal operator intervention," Terry Xu says, explaining that it has more than three times the throughput of a semi-automation or manual system. “So far, it has run in continuous operation without an error. Moreover, the testing repeatability is twice as good as our previous systems.” Enhanced data collection and analysis capabilities have proven particularly valuable for evolving the test process.

“This automated testing platform has fundamentally changed how we innovate,” says Xu. “When you can triple your testing output while improving precision, you're not just solving today's challenges – you're accelerating the future of display technology.”