Semiconductor manufacturing equipment motion control

Motion control system for nanometer-level precision wafer scanner

This project is focused on developing motion control technology solutions for semiconductor manufacturing. Our technology, methods, and experience will enable equipment manufacturers to offer the best equipment in the industry capable of manufacturing cutting-edge chips with smaller features and tighter tolerances, helping their customers achieve their density and manufacturing throughput and yield targets

Semiconductor manufacturing technology?
Semiconductors are manufactured by building up intricate and miniature circuits a layer at a time.
Circuits are created by depositing layers of various chemicals and transferring patterns to make the circuit using a short-wavelength lightsource and pattern mask in the step called photolithography.
Semiconductors are manufactured in cleanrooms and much of the process is automated using specialized robotic manufacturing equipment.

How does control technology help semiconductor manufacturing?

The semiconductor industry has set a technology roadmap with targets for continued feature size reductions and gate density increases into the future. Equipment manufactures are getting ready with new equipment to support the higher demands created by smaller features. The position control systems of manufacturing equipment must be able to keep up with these density increases in order to maximize the potential of other density-enabling technologies.

Advanced motion control technology will help to manufacture smaller and smaller features to within tight tolerances, irregardless of unpredictable operating conditions, external disturbances, and vibrations. Control technology is also a major contributor to manufacturing capability. Fast and precise motion will reduce the time required per product, increase the throughput of the manufacturing machines, and improve overall yield.

Some examples…
Motion control encompasses a variety of hardware and control algorithm technologies to make all of this possible. For example, a wafer scanner could have the following features:

Hardware technology:

  • frictionless environment (we create an ultra-low-friction environment through brushless motors and air bearings)
  • precise sensing (we sense position to sub-nanometer accuracy using laser interferometry)
  • isolated from shocks (we isolate the entire system from the environment by mounting it on a vibration isolation table)
  • precise control and synchronization of timing (we chose hardware with precise timing control and synchronize sensor sampling to keep jitter under control)

Control and algorithms technology:

  • feedback control
  • trajectory shaping
  • automated controller tuning
  • disturbance modeling
  • feedforward
  • iterative learning
This research project was undertaken with the support and sponsorship of the Mechatronics Systems and Controls Laboratory, University of California, Berkeley, and Nikon Research Corporation of America.