There’s a booming industry demand for microchips, which are used in virtually all electronic devices today. But meeting that demand is challenging for chipmakers, because current mechatronic systems have reached the limit for how fast they can produce chips.
With a National Science Foundation CAREER Award, Lei Zhou, an assistant professor of mechanical engineering and electrical and computer engineering at the University of Wisconsin-Madison, aims to push mechatronic systems past that limit. By developing theoretical methods and practical tools, she seeks to enable future integrated circuit manufacturing equipment that can complete critical manufacturing processes faster, thereby increasing the number of chips that can be produced.
In integrated circuit manufacturing, motion stages are mechanical platforms or systems that move and precisely position wafers or photomasks during critical manufacturing processes like photolithography and wafer inspection.
“The motion stages move at a very high speed and with nanometer-level precision, and how fast these platforms can accelerate and decelerate, along with the control performance, directly determines the chip throughput for the photolithography and wafer-inspection processes,” Zhou says.
However, in today’s mechatronic systems, there is a fundamental tradeoff between the achievable acceleration for the motion stage and the control bandwidth needed to ensure nanometer accuracy. For her CAREER project, Zhou will create a new mechatronic hardware and control co-design paradigm to transcend this acceleration-bandwidth tradeoff and enable motion systems with substantially improved acceleration—without sacrificing control performance.
“This research has the potential for big societal impact by enabling improved productivity for chip manufacturers,” Zhou says.
Her new approach involves removing material from the motion stage to make the structure lighter and more flexible. In addition, she will use distributed actuators and sensors to control the structure’s flexible dynamics and correct for vibrations.
“For this project, we’ll investigate the mechanical design and control systems together using co-optimization techniques, which could allow us to take advantage of some synergies,” she says.
Other applications that could benefit from this research include laser-based machining, high-power-density electric machines, aerospace structures and adaptive optics for space telescopes.
The project’s education component focuses on enhancing students’ real-world engineering training in system-level synergistic thinking. Zhou is implementing project-based learning experiences in her undergraduate and graduate courses on mechatronics and advanced control. The projects will be industry-relevant and provide students with training that more closely resembles a professional engineering setting.
Featured photo of Assistant Professor Lei Zhou in her mechatronics lab by Joel Hallberg