University of Michigan

Luis P Bernal

Khalil Najafi

Peter D Washabaugh

Hanseup S Kim

Seyed Amin Sandoughsaz Zardini

Aaron A Astle

Ali Besharatian

Tsung-Kuan A Chou

A micropump assembly is comprised of modular stacked pump stages. The modular pump stages are preferably stacked vertically on top of each other. The stacked design allows each pumping chamber to be compressed by two pumping membranes and thereby provide twice the compression as compared to conventional planar pump designs. The stacked design also eliminates the need for bidirectional movement of the pumping membrane. Lastly, the number of stacked pumping stages can be changed post-fabrication to achieve the required pressure for a given application.

Modular stacked variable-compression micropump and method of making same

A MEMS-fabricated microvacuum pump assembly is provided. The pump assembly is designed to operate in air and can be easily integrated into MEMS-fabricated microfluidic systems. The pump assembly includes a series of pumping cavities with electrostatically-actuated membranes interconnected by electrostatically-actuated microvalves. A large deflection electrostatic actuator has a curved fixed drive electrode and a flat movable polymer electrode. The curved electrodes are fabricated by buckling the electrode out-of-plane using compressive stress, and the large deflection parallel-plane electrostatic actuators are formed by using the curved electrode. The curved electrode allows the movable electrode to travel over larger distances than is possible using a flat electrode, with lower voltage. The movable electrode is a flat parylene membrane that is placed on top of the curved electrode using a wafer-level transfer and parylene bonding process. Using this approach, large out-of-plane deflection of the parylene membrane is achieved using a voltage smaller than is achievable using flat parallel-plate electrodes.

Micropump assembly for a microgas chromatograph and the like

A method of low-temperature (150-300&#xb0; C.) patterned wafer bonding of complex 3D MEMS comprising providing a first pre-processed wafer having a first surface and a second pre-processed wafer having a second surface. Photosensitive benzocyclobutene (BCB) polymer is then applied to the first surface of the first wafer in a predetermined pattern to define a bonding layer. The second wafer is then bonded to the first wafer only along the bonding layer.

Low-temperature patterned wafer bonding with photosensitive benzocyclobutene (BCB) and 3D MEMS (microelectromechanical systems) structure fabrication

Growing community of inventors

Ann Arbor, MI, United States of America

Luis P Bernal