Smart Manufacturing In Fabs

Not long after STMicroelectronics opened its first semiconductor plant in Singapore more than 50 years ago, a facility chiefly focused on chip assembly and packaging, the company realized that it had constructed the site in an area with a blossoming chip ecosystem with a bright future. Before long, the company became the first to start a wafer fab facility in the so-called Little Red Dot.

Today, our STMicroelectronics Singapore campus sports several buildings that dwarf the original site in the sprawling Ang Mo Kio Industrial Park 2. The facilities feature advanced 200mm manufacturing lines but still produce huge volumes of chips with more than 1,000 pieces of 150mm manufacturing equipment.

Much of the wafer equipment dates back to the past century so is no longer supported by the manufacturers, if they’re still even in existence. Yet decades later the chipmaking gear continues to operate with a surprising reliability that far surpasses the longevity called for in its manufacturing specifications, thanks to replacement parts and frequent upgrades with more sophisticated handling robots and chucks. Now, as smart manufacturing begins to establish a foothold in the semiconductor industry, Industry 4.0 technology is breathing new life into these aging workhorses.

Despite its age, all of the equipment adheres to industry manufacturing standards. The gear is remotely controlled using the SECS/GEM interface protocol that was either originally integrated with the equipment controller or custom-made. We’ve also maximized its usage through advanced recipe management, advanced alarm and event handling, and secured loT identification.

Crucially, we decided to systematically deploy a real-time fault detection and classification (FDC) solution using a third-party product based on what today is known as an edge computing architecture. Every piece of critical processing equipment is progressively paired with its dedicated FDC instance running on a virtual machine in the wafer fab data center, and the FDC solution monitors vital equipment parameters at high frequency – depending on the SECS/GEM capabilities of the equipment – and analyzes incoming manufacturing data in real time using classic SPC (statistical process control) algorithms and even AI-class protocols.

Our use of the FDC edge solution as a sensor signal aggregator has given our equipment a second life. The solution processes real-time signals from sensors connected through a typical TCP-IP. Sensors have been the old equipment’s saving grace with their ability to de-multiply equipment capabilities and overcome fundamental shortcomings and design weaknesses.

The STMicroelectronics Singapore plant first used off-the-shelf sensor nodes with built-in power amplifier and analog input nodes. While very practical and easy to implement, deploying the nodes can be costly. After developing more expertise in sensor integration using FDC, our wafer fab equipment experts decided to design an in-house solution based on the famed STM32 microcontroller. Leveraging Arduino – an open-source electronics platform with easy-to-use hardware and software – the equipment teams can now design and program a variety of in-house sensors for measurements including temperature, humidity, waterflow and pressure. The sensors are integrated with process equipment using the FDC solution.

Integrating the sensors with the FDC engine on the edge computer extends the capabilities of old equipment without jeopardizing the integrity of the machines themselves. While the integration can be quick, it must be robust to ensure the reliability of the new measurements. Similarly, ever-increasing connectivity requirements present clear cybersecurity risks that must be managed upfront and each solution must be hardened to minimize security vulnerabilities.

Even so, the challenges and risks pale in comparison to the benefits!