Pattern transfer by solid state electrochemical stamping

Abstract

The present invention provides an electrochemical fabrication platform for making structures, arrays of structures and functional devices having selected nanosized and / or microsized physical dimensions, shapes and spatial orientations. Methods, systems and system components of the present invention use an electrochemical stamping tool for generating patterns of relief and / or recessed features exhibiting excellent reproducibility, pattern fidelity and resolution on surfaces of solid state ionic conductors and in metal. Electrochemical stamping tools of the present invention are capable high throughput patterning of large substrate areas and, thus, enable a robust and commercially attractive manufacturing pathway to a range of functional systems and devices including nano- and micro-electromechanical systems, sensors, energy storage devices and integrated electronic circuits.

Description

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT [0001] This invention was made, at least in part, with United States governmental support awarded by National Science Foundation under contract number DMI-0328162. The United States government has certain rights in this invention.CROSS-REFERENCE TO RELATED APPLICATIONS [0002] Not Applicable. BACKGROUND OF THE INVENTION [0003] The use of solid state ionic conductors allows for nano-scale patterning and stamping by highly localized electrochemical etching and deposition. When an electric field is applied by two electrodes in contact with a material that exhibits ionic conduction, the metal ions near one of the electrodes migrate through the bulk of the ionic conductor, and, upon receiving electrons at the counter electrode, reduce back to metal atoms precipitating at the interface. Alternatively, under a reverse potential, a counter electrode of the metal is etched. By nano-patterning the contact between the electrode and...

AI Technical Summary

Benefits of technology

[0010] The present invention provides an electrochemical fabrication platform for making structures, arrays of structures and functional devices having selected nanosized and / or microsized physical dimensions, shapes and spatial orientations. Methods, systems and system components of the present invention use an electrochemical stamping tool for generating patterns of relief and / or recessed features exhibiting excellent reproducibility, pattern fidelity and resolution on surfaces of solid state ionic conductors and in metal layers. Electrochemical stamping tools of the present invention are capable high throughput patterning of large substrate areas and, thus, enable a robust and commercially attractive manufacturing pathway to a range of functional systems and devices including nano- and micro-electromechanical systems, sensors, energy storage devices and integrated electronic circuits. Further, nanopatterning and micropatterning methods and systems of the present invention are compatible with a wide range of materials, including metals, metal alloys, ionic conductors and superionic conductors, and processing conditions, including room temperature (below about 30° C.) processing.

[0015] In another embodiment of this aspect of the present invention, a structure or pattern of structures are electrochemically deposited onto a surface of the solid state ionic conductor using a stamping tool that is the first electrode itself. In one embodiment, for example, a first electrode-stamping tool is provided that has a selected shape that generates a selected pattern of electrical contacts between the first electrode-stamping tool and a surface of the solid state ionic conductor undergoing processing / patterning. Application of an electric field between a first electrode provided at a lower electric potential and a second electrode provided at a higher electrodic potential, results in oxidation of metal atoms of the metal, thereby generating metal ions that migrate to points of electrical contact in the pattern of electrical contacts established between the first electrode-stamping tool and the surface of the solid state ionic conductor. In this method, reduction of metal ions at the interface between the first electrode-stamping tool and the solid state ionic conductor results in localized electrochemical deposition of metal at regions of the solid state ionic conductor in electrical contact with the stamping tool.

[0017] In methods of the present invention useful for certain applications it is beneficial to use a combination of a metal and solid state ionic conductor comprising metal atoms that having an elemental composition that corresponds to that of the metal used during processing. Use of a combination of elementally matched metal and ionic conductor materials is useful because cations generated from the metal generally will exhibit good transport properties and conductance through the matched solid state ionic conductor in the presence of an electric field, thereby allowing for useful etch rates or deposition rates in the present methods. The present invention includes methods, devices and systems using a combination of a metal and solid state conductor that do not have matched elemental composition with regard to the atomic composition of the metal and the solid state ionic conductor. In these methods and systems, therefore, the composition of the solid state ionic conductor is selected such that it comprises an atom having an elemental composition different from than that of the metal. In these elementally unmatched metal and ionic conductor systems it is useful to choose a metal that generates cations that are capable of efficient transport through the solid state ionic conductor and which exhibit appreciable solubility in the solid state ionic conductor, such that appreciable etching rates and deposition rates may be achieved.

[0020] Useful stamping tools for certain embodiments of the present invention have a Young's modulus selected from the range of about 20 GPa to about 200 GPa. A benefit of stamping tools of the present invention having a Young's modulus in this range is that they are less susceptible to pattern distortion than polymeric stamping tools and stamps used in conventional soft lithography patterning techniques, such as conventional nanoimprint lithography. Accordingly, the methods, patterning systems and stamping tools of the present invention are capable of providing good pattern fidelity and high resolution patterning (e.g. resolution less than about 100 nanometers, and more preferably for some applications less than about 50 nanometers). An advantage provided by the present methods, therefore, is the ability to use stamping tools comprising solid state ionic conductor materials having a Young's modulus selected over the range at about 20 GPa to about 200 GPa, which are beneficial for minimizing or completely avoiding stamp distortion during processing.

Problems solved by technology

However, a liquid electrolyte, which is difficult to handle, is required as a conducting medium between the two electrodes.

None of these methods, however, are fully adaptable to massive manufacturing due to the slow serial scanning process.

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