Method for selectively filling, with a filling liquid, a group of cavities from among a plurality of cavities
A method for selectively filling, with a filling liquid, a first cavity from among a plurality of cavities, each cavity opening out at a front face of a substrate. The method includes a processing step for altering the surface energy of the first internal surface of the first cavity or the surface energy of the second internal surfaces of the other cavities, such that the first surface has a first surface energy and the second surfaces have a second surface energy, and a step including a sequence for spreading the filling liquid, the first energy and the second energy being adjusted such that the first and the second surfaces exert an attracting effect and a repelling effect, respectively, on the liquid.
1 . A method for selectively filling, with a filling liquid, a first cavity of at least one group of cavities each opening out onto a front face of a substrate, each of the cavities comprising an inner surface, the method comprising the following steps:
a) a treatment step for modifying a surface energy of the inner surface of the first cavity, referred to as a first surface, and surface energies of the inner surfaces, referred to as second surfaces, of second cavities other than the first cavity, such that the first surface has a first surface energy and the second surfaces have a second surface energy different from the first energy; and
b) a step which comprises at least one sequence of spreading the filling liquid on the front face,
the first surface energies and the second surface energies being adjusted such that the first and the second surfaces exert an attracting and repelling effect respectively on the filling liquid, step b) thus resulting in the selective filling, by the filling liquid, of the first cavity with respect to the second cavities,
wherein step a) comprises a plasma treatment or a treatment with ultraviolet radiation performed selectively on the first surface or on the second surfaces, and
wherein step b) comprises:
spreading a first liquid to fill the first cavity, and
spreading a second liquid over the first and second cavities, filling at least one of the second cavities and forming a layer of the second liquid remaining to cover the filled first cavity.
2 . The method for selectively filling according to claim 1 , wherein step a) is executed selectively on the first surface or on the second surfaces by masking, respectively, the second surfaces or the first surface.
3 . The method for selectively filling according to claim 1 ,
wherein step a) is preceded by a step a1) of forming a passivation layer by covering the first surface and the second surfaces, the passivation layer being made from an active material configured to modify its surface energy on an effect of the treatment of step a).
4 . The method for selectively filling according to claim 3 , wherein the passivation layer comprises at least one of the materials selected from among: a siloxane compound, a fluorosilane, a fluoropolymer, octadecyltriethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, octadecyltrimethoxysilane, octyltrimethoxysilane, octyltriethoxysilane, dodecyltriethoxysilane, dimethoxy-methyl (3,3,3-trifluoropropyl)silane, trichloro(octadecyl)silane, trichloro(3,3,3-trifluoropropyl)silane, 1H, 1H,2H,2H-perfluorodecyltrimethoxysilane.
5 . The method for selectively filling according to claim 3 , wherein the passivation layer is formed according to one of a chemical vapour phase deposition method and a chemical vapour phase deposition method activated by plasma.
6 . The method for selectively filling according to claim 1 , wherein the filling liquid is a mixture which comprises a solvent, a filling matrix and an active charge.
7 . The method for selectively filling according to claim 6 , wherein step b) comprises a plurality of sequences of spreading filling liquid, and executing a sequence of evaporation of the solvent following each spreading sequence.
8 . The method for selectively filling according to claim 7 , wherein the sequence of evaporation of the solvent comprises a heat treatment step for evaporating the solvent.
9 . The method for selectively filling according to claim 6 , wherein the solvent comprises a solution of propylene glycol monomethyl ether acetate.
10 . The method for selectively filling according to claim 6 , wherein the filling matrix comprises an acrylate type transparent material.
11 . The method for selectively filling according to claim 6 , wherein the active charge comprises a conversion material being one of quantum dots or phosphors.
12 . The method for selectively filling according to claim 1 , wherein a bottom of each of the cavities is functionalised.
13 . The method for selectively filling according to claim 12 , wherein the functionalisation of the bottom of each of the cavities comprises using a light-emitting diode having a form of one of at least one nanowire, at least one microwire, and at least one pyramid.
14 . A method of manufacture including filling cavities of a group of cavities with a different filling liquid, the method of manufacture comprising successive filling of cavities among the group of cavities according to the filling method according to claim 1 .
15 . The method according to claim 14 , wherein the group of cavities forms a pixel of a display device.
16 . The method according to claim 15 , wherein each of the cavities forming the pixel emits a different colour.
17 . The method for selectively filling according to claim 1 , wherein
each of the first and second cavities has a bottom and lateral walls delimiting a cavity volume, and
the cavity volumes are separate and non-overlapping.
18 . The method for selectively filling according to claim 17 , wherein step a) is executed selectively on the first surface or on the second surfaces by masking, respectively, the second surfaces or the first surface.
19 . The method for selectively filling according to claim 1 , wherein
each of the first and second cavities has a bottom and lateral walls delimiting a cavity volume,
the cavity volumes are separate and non-overlapping, and
step a) is preceded by a step a1) of forming a passivation layer by covering the first surface and the second surfaces, the passivation layer being made from an active material configured to modify its surface energy on an effect of the treatment of step a).
20 . The method for selectively filling according to claim 19 , wherein the passivation layer comprises at least one of the materials selected from among: a siloxane compound, a fluorosilane, a fluoropolymer, octadecyltriethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, octadecyltrimethoxysilane, octyltrimethoxysilane, octyltriethoxysilane, dodecyltriethoxysilane, dimethoxy-methyl(3,3,3-trifluoropropyl)silane, trichloro(octadecyl)silane, trichloro(3,3,3-trifluoropropyl)silane, 1H, 1H,2H,2H-perfluorodecyltrimethoxysilane.
21 . The method for selectively filling according to claim 19 , wherein the passivation layer is formed according to one of a chemical vapour phase deposition method and a chemical vapour phase deposition method activated by plasma.
22 . The method for selectively filling according to claim 17 , wherein the filling liquid is a mixture which comprises a solvent, a filling matrix and an active charge.
23 . The method for selectively filling according to claim 22 , wherein step b) comprises a plurality of sequences of spreading filling liquid, and executing a sequence of evaporation of the solvent following each spreading sequence.
24 . The method for selectively filling according to claim 23 , wherein the sequence of evaporation of the solvent comprises a heat treatment step for evaporating the solvent.
25 . The method for selectively filling according to claim 22 , wherein the solvent comprises a solution of propylene glycol monomethyl ether acetate.
26 . The method for selectively filling according to claim 22 , wherein the filling matrix comprises an acrylate type transparent material.
27 . The method for selectively filling according to claim 22 , wherein the active charge comprises a conversion material being one of quantum dots or phosphors.
28 . The method for selectively filling according to claim 17 , wherein the bottom of each of the cavities is functionalised.
29 . The method for selectively filling according to claim 28 , wherein the functionalisation of the bottom of each of the cavities comprises using a light-emitting diode having a form of one of at least one nanowire, at least one microwire, and at least one pyramid.
30 . A method of manufacture including filling cavities of a group of cavities with a different filling liquid, the method of manufacture comprising successive filling of cavities among the group of cavities according to the filling method according to claim 17 .
31 . The method according to claim 30 , wherein the group of cavities forms a pixel of a display device.
32 . The method according to claim 31 , wherein each of the cavities forming the pixel emits a different colour.
33 . The method for selectively filling according to claim 1 , wherein the first and second liquids are different from each other.