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Results for “elastomeric stamp”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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Clean Graphene Electrodes on Organic Thin-Film Devices via Orthogonal Fluorinated Chemistry

Graphene is a promising flexible, highly transparent, and elementally abundant electrode for organic electronics. Typical methods utilized to transfer large-area films of graphene synthesized by chemical vapor deposition on metal catalysts are not compatible with organic thin-films, limiting the integration of graphene into organic optoelectronic devices. This article describes a graphene transfer process onto chemically sensitive organic semiconductor thin-films. The process incorporates an elastomeric stamp with a fluorinated polymer release layer that can be removed, post-transfer, via a fluorinated solvent; neither fluorinated material adversely affects the organic semiconductor materials. We used Raman spectroscopy, atomic force microscopy, and scanning electron microscopy to show that chemical vapor deposition graphene can be successfully transferred without inducing defects in the graphene film. To demonstrate our transfer method’s compatibility with organic semiconductors, we fabricate three classes of organic thin-film devices: graphene field effect transistors without additional cleaning processes, transparent organic light-emitting diodes, and transparent small-molecule organic photovoltaic devices. Furthermore, these experiments demonstrate the potential of hybrid graphene/organic devices in which graphene is deposited directly onto underlying organic thin-film structures.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Printing transferable components using microstructured elastomeric surfaces with pressure modulated reversible adhesion

In a method of printing a transferable component, a stamp including an elastomeric post having three-dimensional relief features protruding from a surface thereof is pressed against a component on a donor substrate with a first pressure that is sufficient to mechanically deform the relief features and a region of the post between the relief features to contact the component over a first contact area. The stamp is retracted from the donor substrate such that the component is adhered to the stamp. The stamp including the component adhered thereto is pressed against a receiving substrate with a second pressure that is less than the first pressure to contact the component over a second contact area that is smaller than the first contact area. The stamp is then retracted from the receiving substrate to delaminate the component from the stamp and print the component onto the receiving substrate. Related apparatus and stamps are also discussed.

36 MATERIALS SCIENCE↗

Printing transferable components using microstructured elastomeric surfaces with pressure modulated reversible adhesion

In a method of printing a transferable component, a stamp including an elastomeric post having three-dimensional relief features protruding from a surface thereof is pressed against a component on a donor substrate with a first pressure that is sufficient to mechanically deform the relief features and a region of the post between the relief features to contact the component over a first contact area. The stamp is retracted from the donor substrate such that the component is adhered to the stamp. The stamp including the component adhered thereto is pressed against a receiving substrate with a second pressure that is less than the first pressure to contact the component over a second contact area that is smaller than the first contact area. The stamp is then retracted from the receiving substrate to delaminate the component from the stamp and print the component onto the receiving substrate. Related apparatus and stamps are also discussed.

Menard, Etienne↗

Printing transferable components using microstructured elastomeric surfaces with pressure modulated reversible adhesion

In a method of printing a transferable component, a stamp including an elastomeric post having three-dimensional relief features protruding from a surface thereof is pressed against a component on a donor substrate with a first pressure that is sufficient to mechanically deform the relief features and a region of the post between the relief features to contact the component over a first contact area. The stamp is retracted from the donor substrate such that the component is adhered to the stamp. The stamp including the component adhered thereto is pressed against a receiving substrate with a second pressure that is less than the first pressure to contact the component over a second contact area that is smaller than the first contact area. The stamp is then retracted from the receiving substrate to delaminate the component from the stamp and print the component onto the receiving substrate. Related apparatus and stamps are also discussed.

36 MATERIALS SCIENCE↗

Active, Programmable Elastomeric Surfaces with Tunable Adhesion for Deterministic Assembly by Transfer Printing

Active, programmable control of interfacial adhesion is an important, desired feature of many existing and envisioned systems, including medical tapes, releasable joints, and stamps for transfer printing. Here a design for an elastomeric surface that offers switchable adhesion strength through a combination of peel-rate dependent effects and actuation of sub-surface fluid chambers is presented. Microchannels and open reservoirs positioned under a thin surface membrane can be pressurized in a controlled manner to induce various levels of surface deformation via inflation. These pressurized structures demonstrate utility in controllably decreasing the strength of adhesion of flat, solid objects to the elastomeric surface, particularly in the limit of low peel-rates. Experimental and theoretical studies of these systems reveal the key mechanisms, and guide optimized geometries for broad control over adhesion, in a programmable and reversible manner. Implementing these concepts in stamps for transfer printing enables new modes for deterministic assembly of micro- and nanoscale materials onto diverse types of substrates. Furthermore, collections of silicon plates delivered onto plastic, paper and other surfaces with single or multiply addressable stamps illustrate some of the capabilities.

36 MATERIALS SCIENCE↗