MULTILAYER FILM FOR ENCAPSULATING OXYGEN AND/OR MOISTURE SENSITIVE ELECTRONIC DEVICES

• US 20110132449A1
• Filed: 04/08/2009
• Published: 06/09/2011
• Est. Priority Date: 04/09/2008
• Status: Active Grant

• Current Assignee: Agency For Science Technology and Research
• Original Assignee: Agency For Science Technology and Research
• Inventors: Ke, Lin Karen, Ramadas, Senthil Kumar, Chua, Soo Jin
• Granted Patent: US 10,103,359 B2
• Time in Patent Office: Days
• US Class Current: 136/256
• CPC Class Codes: B32B 2457/206 Organic displays, e.g. OLED
• CPC Class Codes: B32B 27/20 using fillers, pigments, thixotroping agents
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: H05B 33/04 Sealing arrangements , e.g. against humidity
• CPC Class Codes: H05B 33/10 Apparatus or processes specially adapted to the manufacture of electroluminescent light sources
• CPC Class Codes: H10K 2102/331 Nanoparticles used in non-emissive layers, e.g. in packaging layer
• CPC Class Codes: H10K 30/88 Passivation; Containers; Encapsulations
• CPC Class Codes: H10K 50/841 Self-supporting sealing arrangements
• CPC Class Codes: H10K 50/8445 multilayered coatings having a repetitive structure, e.g. having multiple organic-inorganic bilayers
• CPC Class Codes: H10K 50/846 comprising getter material or desiccants
• CPC Class Codes: H10K 50/865 comprising light absorbing layers, e.g. light-blocking layers
• CPC Class Codes: H10K 71/00 Manufacture or treatment specially adapted for the organic devices covered by this subclass
• CPC Class Codes: Y02E 10/549 Organic PV cells
• CPC Class Codes: Y10T 428/24995 Two or more layers
• CPC Class Codes: Y10T 428/25 Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles
• CPC Class Codes: Y10T 428/31504 Composite [nonstructural laminate]
• CPC Class Codes: Y10T 428/31507 Of polycarbonate
• CPC Class Codes: Y10T 428/31511 Of epoxy ether
• CPC Class Codes: Y10T 428/31533 Of polythioether
• CPC Class Codes: Y10T 428/3154 Of fluorinated addition polymer from unsaturated monomers
• CPC Class Codes: Y10T 428/31551 : Of polyamidoester [polyurethane, polyisocyanate, polycarbamate, etc.]
• CPC Class Codes: Y10T 428/31663 : As siloxane, silicone or silane
• CPC Class Codes: Y10T 428/31678 : Of metal
• CPC Class Codes: Y10T 428/31721 : Of polyimide
• CPC Class Codes: Y10T 428/31725 : Of polyamide
• CPC Class Codes: Y10T 428/31931 : Polyene monomer-containing
• CPC Class Codes: Y10T 428/31935 : Ester, halide or nitrile of addition polymer
• CPC Class Codes: Y10T 428/31938 : Polymer of monoethylenically unsaturated hydrocarbon

Abstract

The present invention refers to a multilayer barrier film capable of encapsulating a moisture and/or oxygen sensitive electronic or optoelectronic device, the barrier film comprises at least one nanostructured layer comprising reactive nanoparticles capable of interacting with moisture and/or oxygen, the reactive nanoparticles being distributed within a polymeric binder, and at least one ultraviolet light neutralizing layer comprising a material capable of absorbing ultraviolet light, thereby limiting the transmission of ultraviolet light through the barrier film

Claims

1-64. -64. (canceled)

65. A multilayer barrier film capable of encapsulating a moisture and/or oxygen sensitive electronic or optoelectronic device, said barrier film comprising:

at least one nanostructured layer comprising reactive nanoparticles capable of interacting with moisture and/or oxygen, and inert nanoparticles which do not interact with moisture and/or oxygen and which are adapted to obstruct the permeation of moisture and/or oxygen, said reactive nanoparticles and inert nanoparticles being distributed within a polymeric binder, and

at least one ultraviolet light neutralizing layer comprising a material capable of absorbing ultraviolet light, thereby limiting the transmission of ultraviolet light through the barrier film.

66. The barrier film of claim 65, wherein the reactive nanoparticles are capable of interacting with moisture and/or oxygen through chemical reaction.

67. The barrier film of claim 66, wherein the reactive nanoparticles comprise a material selected from the group consisting of metals, metal oxides and mixtures thereof.

68. The barrier film of claim 67, wherein the reactive nanoparticles comprise a metal selected from the group consisting of Al, Ti, Mg, Ba Ca, and mixtures thereof.

69. The barrier film of claim 67, wherein the reactive nanoparticles comprise a metal oxide selected from the group consisting of TiO₂, Al₂O₃, ZrO₂, ZnO, BaO, SrO, CaO and MgO, VO₂, CrO₂, MoO₂, LiMn₂O₄, cadmium stannate (Cd₂SnO₄), cadmium indate (CdIn₂O₄), zinc stannate (Zn₂SnO₄ and ZnSnO₃), zinc indium oxide (Zn₂In₂O₅) and mixtures thereof.

70. The barrier film of claim 65, wherein the reactive nanoparticles are capable of interacting with moisture and/or oxygen through adsorption.

71. The barrier film of claim 70, wherein the reactive nanoparticles comprise carbon nanotubes.

72. The barrier film of claim 65, wherein the nanostructured layer comprises both carbon nanotubes and reactive metal oxide nanoparticles, the amount of metal oxide nanoparticles present being between 500 to 15000 times (by weight) the quantity of carbon nanotubes present.

73. The barrier film of claim 65, wherein when the oxygen and/or moisture sensitive electronic device comprises an organic light emitting device, the average size of the reactive nanoparticles is less than one-half the characteristic wavelength of light produced by the organic light emitting device.

74. The barrier film of claim 65, wherein the at least one nanostructured layer of the multilayer film comprises at least 2 types of reactive nanoparticles that are capable of interacting with moisture and/or oxygen.

75. The barrier film of claim 74, wherein the multilayer film comprises a first nanostructured layer comprising reactive metal nanoparticles, and a second nanostructured layer comprising reactive metal oxide nanoparticles.

76. The barrier film of claim 75, wherein the multilayer film comprises a plurality of said first and said second nanostructured layers arranged in alternating sequence in the multilayer film.

77. The barrier film of claim 74, wherein the multilayer film comprises one nanostructured layer having distributed therein reactive metal nanoparticles and reactive metal oxide nanoparticles.

78. The barrier film of claim 65, wherein the amount of reactive nanoparticles present in the nanostructured layer is between about 0.0000001% to about 50% by weight of the monomer of the polymeric binder in the nanostructured layer.

79. The barrier film of claim 78, wherein the polymeric binder comprises a material selected from the group consisting of polyacrylate, polymethacrylate, polyacrylamide, polyepoxide, parylene, polysiloxanes and polyurethane.

80. The barrier film of claim 65, wherein the ultraviolet light neutralizing layer and/or the polymeric binder in which the reactive nanoparticles are distributed comprises an organic compound capable of absorbing ultraviolet light selected from the group consisting of 4-methylbenzylidene camphor, isoamyl p-methoxycinnamate, 2-hydroxyphenyl benzotriazole, 2-hydroxy-benzophenone, 2-hydroxy-phenyltriazine and oxalanilide.

81. The barrier film of claim 65, wherein the ultraviolet light neutralizing layer comprises reactive metal oxide nanoparticles distributed in a polymer layer.

82. The barrier film of claim 81, wherein the reactive metal oxide nanoparticles being selected from the group consisting of hafnium dioxide (HfO₂), magnesium oxide (MgO), barium oxide (BaO), silicone oxide (SiO₂) titanium dioxide (TiO₂), tantalum oxide (Ta₂O₅), cerium oxide (CeO₂), niobium oxide (Nb₂O₅), zirconium oxide (ZrO₂), zinc oxide (ZnO) and mixtures thereof.

83. The barrier film of claim 80, wherein the ultraviolet light neutralizing layer comprises

an organic compound capable of absorbing ultraviolet light and reactive metal oxide nanoparticles distributed in a polymer layer.

84. The barrier film of claim 65, wherein the multilayer film further comprises an organic barrier layer.

85. The barrier film of claim 84, wherein the barrier layer comprises a material selected from parylene, polyimide, polyacrylamide, polyamide, polyacetate, polypropylene, polyimide, poly(1-trimethylsilyl-1-propyne, poly(4-methyl-2-pentyne), polyethylene, polyethersulfone, epoxy resins, polyethylene terepthalate, polystyrene, polyurethane, polyacrylate, polydimethylphenylene oxide, styrene-divinylbenzene, polyvinylidene fluoride (PVDF).

86. The barrier film of claim 85, further comprising a substrate for supporting the electronic device to be encapsulated, wherein the barrier film is formed on a surface of the substrate.

87. The barrier film of claim 65, further comprising a terminal layer for protecting the multilayer barrier film.

88. The barrier film of claim 87, wherein the terminal layer comprises a material selected from indium tin oxide (ITO), glass, polypropylene and polycarbonate.

89. The barrier film of claim 88, wherein the terminal layer has distributed therein particles comprising a material selected from BaF₂, MgF₂ and CaF₂.

90. The barrier film of claim 65, wherein the inert nanoparticles are made of a material selected from the group consisting of copper, platinum, gold, silver;

minerals, clays, wollastonite, mullite, monmorillonite;

rare earth elements, silicate glass, fluorosilicate glass, fluoroborosilicate glass, aluminosilicate glass, calcium silicate glass, calcium aluminium silicate glass, calcium aluminium fluorosilicate glass, titanium carbide, zirconium carbide, zirconium nitride, silicon carbide, or silicon nitride, metal sulfides, mixtures and combinations thereof.

91. An encapsulated electronic device, comprising

a base substrate having arranged thereon an electronic device, said electronic device being covered by an encapsulation for protecting the electronic device from moisture and/or oxygen, wherein the encapsulation comprises a barrier film of claim 65.

92. The device of claim 91, further comprising a secondary encapsulation comprising an adhesive layer arranged on the multilayer barrier film, and a cover substrate arranged on the adhesive layer.

93. The device of claim 92, wherein the adhesive layer is selected from the group consisting of ethylene vinyl acetate resins, epoxy resins, polysulfide, silicone and polyurethane.

94. The device of claim 93, wherein the cover substrate is selected from the group consisting of glass, indium tin oxide, nanocomposites laminated with an inorganic barrier film, and transparent plastics.

95. The device of claim 65, wherein the electronic device is selected from the group consisting of an Organic Light Emitting Device (OLED), charged-coupled device (CCD), micro-electro-mechanical sensors (MEMS), and an organic or inorganic photovoltaic device which is based on a thin-film solar cell.

96. An organic electroluminescent (EL) panel comprising a plurality of encapsulated organic light emitting devices (OLEDs), said panel comprising:

a substrate having arranged thereon said plurality of encapsulated OLEDs, each encapsulated OLED comprising;

a base substrate having arranged thereon an OLED including a first electrode layer, an organic layer, and a second electrode layer;

said OLED being enclosed within a multilayer film according to claim 65 for protecting the OLED from moisture and/or oxygen.

97. An encapsulated photovoltaic device comprising:

a photovoltaic device being sandwiched between two multilayer barrier films according to claim 65 for protecting said photovoltaic device from moisture and/or oxygen;

wherein each of said multilayer barrier films comprise a nanostructured layer which is attached to said photovoltaic device on one side and to an ultraviolet light neutralizing layer on the opposing side.

98. A method of fabricating an encapsulated electronic device, comprising:

providing a vacuum enclosure,

arranging within the vacuum enclosure a base substrate having arranged thereon an electronic device to be encapsulated, and

forming a multilayer barrier film according to claim 65 on the electronic device, thereby encapsulating the electronic device.

99. The method of claim 98, wherein forming the multilayer barrier film comprises:

forming a first layer comprising a material capable of absorbing ultraviolet light onto the electronic device,

mixing reactive nanoparticles capable of interacting with moisture and/or oxygen and inert nanoparticles which do not interact with moisture and/or oxygen and which are adapted to obstruct the permeation of moisture and/or oxygen with a polymerizable compound having at least one polymerisable group to form a nanoparticulate mixture,

applying the nanoparticulate mixture onto the first layer, and

exposing the nanoparticulate mixture to ultraviolet light, thereby forming a second layer.

100. The method of claim 98, further comprising the step of forming a secondary encapsulation over the electronic component,

wherein the multilayer film is contacted with a curable adhesive in an amount sufficient to surround the encapsulation package,

attaching a cover substrate on the adhesive prior to compressing the sealing material against the encapsulation package.

mechanically compressing the cover substrate against the adhesive at an elevated temperature, and

curing the adhesive.

101. A system for fabricating an encapsulated electronic device comprising a base substrate having arranged thereon an electronic device, said electronic device being covered by an encapsulation for protecting the electronic device from moisture and/or oxygen, wherein the encapsulation comprises a barrier film as claimed in claim 65, said system comprising:

a vacuum chamber having arranged therein

a holding jig for receiving an electronic device to be encapsulated,

a loadlock connected to the vacuum chamber, said loadlock being adapted to transport the sample onto the holding jig,

a plasma source for cleaning the electronic device to be encapsulated,

a plurality of material sources adapted to form said barrier film onto the electronic device,

a linear motion drive capable of applying a normal force onto a sample on the holding jig,

a heater coupled to the holding jig for heating the electronic device, and

a UV source for curing the multilayer barrier film.