First Fabrication of MEMS-scale Port Plates and Valve Actuator Arrays using PZT

Achievement date: 

Researchers with the Center for Compact and Efficient Fluid Power (CCEFP), an NSF-funded Engineering Research Center (ERC) headquartered at the University of Minnesota in partnership with the Georgia Institute of Technology, Purdue University, the University of Illinois at Urbana-Champaign, and Vanderbilt University, have successfully fabricated the first MEMS-scale port plates and MEMS-scale valve actuator arrays. The work was completed in collaboration with Penn State University’s (PSU) Nanofabrication Lab.


This work establishes and demonstrates both novel etching and critical fabrication procedures that will enable further development of MEMS-scale devices and components using lead zirconate titanate (PZT) piezoelectric layers. PZT has the best-known piezoelectric properties of any material and is therefore highly desirable for future MEMS applications that require greater sensitivity and the ability to withstand higher operating temperatures.


The CCEFP researchers fabricated the MEMS-scale components as part of efforts to enable MEMS proportional pneumatic valve. The port plates and valve actuator arrays comprise the two most essential elements of MEMS valves.

The first port plate (shown on the left in the figure) contains 6900 orifices with a diameter of 29 microns. The second port plate (on the right) contains 130 orifices with a diameter of 86 microns. The right port plate withstood the full design pressure of 7 bar without fracture. Novel etching procedures were required due to the large ratio of plate thickness to orifice diameter.

The team also developed a piezoelectric actuator array with cantilevered actuators having dimensions of 2000 x 700 x 17 microns. Tip deflections of over 20 microns were measured. The actuators were fabricated using PZT for the piezoelectric layers.

The collaborative work was completed at the Nanofabrication Lab at Penn State University, which is currently the only domestic facility available for fabricating PZT at the MEMS scale. Now that fabrication procedures have been base-lined, the two components will be "tuned" and combined to make complete prototype valves.