Integrated movable micromechanical structures for sensors and actuators
Movable pin-joints, gears, springs, cranks, and slider structures with dimensions measured in micrometers have been fabricated using silicon microfabrication technology. These micromechanical structures, which have important transducer applications, are batch-fabricated with an IC-compatible process. The movable mechanical elements are built on layers that are later removed so that they are freed for translation and rotation. An undercut-and-refill technique, which makes use of the high surface mobility of silicon atoms undergoing chemical vapor deposition, is used to refill undercut regions in order to form restraining flanges. Typical element sizes and masses are measured in micrometers and nanograms. The process provides the tiny structures in an assembled form avoiding the nearly impossible challenge of handling such small elements individually.
Additional Information© Copyright 1988 IEEE. Reprinted with permission. Manuscript received October 1, 1987; revised January 19, 1988. The Berkeley Sensor and Actuator Center is an NSF/Industry/University Cooperative Research Center. This work was partially supported by the U.S. Army Harry Diamond Laboratory. We thank Prof. G. Johnson for valuable discussion on the characterization of polycrystalline films, and K. Voros, R. Hamilton, and the staff of the Berkeley Microfabrication Laboratory for help in experiments and fabrication.
Published - FANieeeted88.pdf