University of California

Muchen Xu

Chang-Jin Kim

A method of forming a microstructured surface includes the operations of depositing electrodes on a surface of a substrate and securing a mold against the surface of the substrate containing the electrodes with a tight contact with the electrodes, the mold containing a plurality of cavities therein. Pressure is applied between the mold and the substrate to force material from the substrate into the plurality of cavities around the electrodes to form a plurality of microfeatures. The mold is separated from the substrate.

Method of forming a microstructured surface

A method of making microstructures having re-entrant or doubly re-entrant topology includes forming a mold defining the negative surface features of the re-entrant or doubly re-entrant topology that is to be formed. In one embodiment, a soft or flowable material is formed on a first substrate and the mold is contacted with the same to form a solid, now positive surface having the re-entrant or doubly re-entrant topology. The mold is then released from the first substrate. The microstructures are secured to a second, different substrate, and the first substrate is removed. Any residual microstructure material located between adjacent microstructures may be removed to form the separate microstructures on the second substrate. The second substrate may be thin and flexible any manipulated into useful or desired shapes having the microstructures on one side thereof.

Method for manufacturing doubly re-entrant microstructures

A low-profile shear-sensing unit includes a floating plate surrounded by a frame and a displacement sensor that measures in-plane movement of the floating plate. Covered with a surface sample, the floating plate is displaced by the friction drag (i.e., shear) on the surface caused by the flow of fluid and the in-plane displacement is measured by the displacement sensor. The shear force on the sample surface is then obtained by multiplying the measured displacement and the spring constant of the flexure beams, which suspend the floating plate. The floating plate and the flexure beams are formed out of one plate or substrate to achieve monolithic construction with a beam geometry that leads to a high-resolution measurement.

Growing community of inventors

Los Angeles, CA, United States of America

Muchen Xu