US 7,615,179 B2 · Method of imprinting shadow mask nanostructures for display pixel segregation

Abstract

The present invention is directed to micro- and nano-scale imprinting methods and the use of such methods to fabricate supported and/or free-standing 3-D micro- and/or nano-structures of polymeric, ceramic, and/or metallic materials, particularly for pixel segregation in OLED-based displays. In some embodiments, a duo-mold approach is employed in the fabrication of these structures. In such methods, surface treatments are employed to impart differential surface energies to different molds and/or different parts of the mold(s). Such surface treatments permit the formation of three-dimensional (3-D) structures through imprinting and the transfer of such structures to a substrate. In some or other embodiments, such surface treatments and variation in glass transition temperature of the polymers used can facilitate separation of the 3-D structures from the molds to form free-standing micro- and/or nano-structures individually and/or in a film. In some or other embodiments, a “latch-on” assembly technique is utilized to form supported and/or free-standing stacked micro- and/or nano-structures that enable the assembly of polymers without a glass transition temperature and eliminate the heating required to assemble thermoplastic polymers.

Claims28

Dependent claims

A method of fabricating T-bar column structures comprising the steps of:

a) providing a first silicon mold comprising a silane-treated surface of low energy with lithographically-generated trenches;
b) spin-coating a polymer comprising a glass transition temperature Tg onto the silane-treated surface of the first silicon mold to form a polymer film which is structured on a first side in contact with the first silicon mold;
c) providing a second silicon mold comprising a silane-treated surface of medium energy with lithographically-generated trenches that are wider than the trenches of the first silicon mold;
d) pressing the silane-treated surface of the second silicon mold into the surface of the polymer film residing in the first silicon mold, at a temperature above Tg, to imprint the second side of the polymer film and yield a series of polymer T-bar structures within the molds;
e) separating the first silicon mold from the series of polymer T-bar structures at a temperature below Tg to yield a series of polymer T-bar structures attached to the second silicon mold;
f) pressing the series of polymer T-bar structures onto a substrate at a temperature below Tg and removing the second mold from the substrate after cooling to near room temperature to yield a series of polymer T-bar structures on the substrate, wherein the structures are connected to each other by a residue film;
and
g) removing the residue film from the series of polymer T-bar structures to yield discrete polymer T-bar structures supported on the substrate.

5 more elements

A method of fabricating shadow-mask structures on a substrate comprising the steps of:

a) providing a first mold comprising a surface of low energy with lithographically-generated trenches;
b) spin-coating a polymer comprising a glass transition temperature Tg onto the surface of the first mold to form a polymer film that is structured on a first side in contact with the first mold;
c) providing a second mold comprising a surface of medium energy with lithographically-generated trenches, wherein the trenches of the second mold are operable for forming shadow-mask structures when combined with the trenches of the first mold under conditions of proper alignment;
d) pressing the surface of the second mold into the surface of the polymer film residing in the first mold, at a temperature above Tg, to imprint the second side of the polymer film and provide a series of polymer shadow-mask structures within the molds;
e) separating the first mold from the series of polymer shadow-mask structures at a temperature below Tg to provide for a series of polymer shadow-mask structures attached to the second mold;
f) pressing the series of polymer shadow-mask structures onto a substrate at a temperature below Tg and removing the second mold from the substrate after cooling to near room temperature to yield a series of polymer shadow-mask structures on the substrate, wherein the structures are connected to each other by a residue film;
and
g) removing the residue film from the series of polymer shadow-mask structures to yield discrete polymer shadow-mask structures supported on the substrate.

5 more elements

Dependencies are inferred from the claim text.

Method of imprinting shadow mask nanostructures for display pixel segregation

Life of this patent

Method of imprinting shadow mask nanostructures for display pixel segregation

Life of this patent

Abstract

Claims28