NANOPARTICULATE ENCAPSULATION BARRIER STACK

• US 20100089636A1
• Filed: 11/06/2006
• Published: 04/15/2010
• Est. Priority Date: 11/06/2006
• Status: Active Grant

• Current Assignee: Agency For Science Technology and Research (Government of Singapore)
• Original Assignee: Agency For Science Technology and Research (Government of Singapore)
• Inventors: Chua, Soo Jin, Ramadas, Senthil Kumar
• Granted Patent: US 9,493,348 B2
• Time in Patent Office: Days
• US Class Current: 174/521
• CPC Class Codes: B82Y 15/00 Nanotechnology for interacting, sensing or actuating, e.g. quantum dots as markers in protein assays or molecular motors
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: B82Y 25/00 Nanomagnetism, e.g. magnetoimpedance, anisotropic magnetoresistance, giant magnetoresistance or tunneling magnetoresistance
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: H10K 2102/331 Nanoparticles used in non-emissive layers, e.g. in packaging layer
• 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: Y10T 428/25 Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles

Abstract

A barrier stack for encapsulating a moisture and/or oxygen sensitive electronic device is provided. The barrier stack comprises a multilayer film having at least one barrier layer having low moisture and/or oxygen permeability, and at least one sealing layer arranged to be in contact with a surface of the barrier layer, wherein the sealing material comprises reactive nanoparticles capable of interacting with moisture and/or oxygen, thereby retarding the permeation of moisture and/or oxygen through defects present in the barrier layer.

Claims

1-60. -60. (canceled)

61. An encapsulation barrier stack capable of encapsulating a moisture and/or oxygen sensitive article, comprising:

a multilayer film to be arranged on a substrate, said multilayer film having at least one barrier layer having low moisture and/or oxygen permeability, and at least one sealing layer arranged to be in contact with a surface of the at least one barrier layer, thereby covering defects present in the barrier layer,

wherein

the at least one sealing layer comprises reactive nanoparticles capable of interacting with moisture and/or oxygen to retard the permeation of moisture and/or oxygen through the defects present in the barrier layer.

62. The barrier stack of claim 61, wherein the at least one sealing layer conforms substantially to the shape of the defects present on the surface of the at least one barrier layer.

63. The barrier stack of claim 61, wherein the nanoparticles comprise a material selected from the group consisting of metals and metal oxides.

64. The barrier stack of claim 63, wherein the nanoparticles comprise a metal selected from the group consisting of Al, Ti, Mg, Ba and Ca.

65. The barrier stack of claim 63, wherein the nanoparticles comprise a metal oxide selected from the group consisting of TiO2, Al2O3, ZrO2, ZnO, BaO, SrO, CaO and MgO, VO2, CrO2, MoO2, and LiMn2O4 or a transparent conductive oxide selected from the group consisting of cadmium stannate (Cd2SnO4), cadmium indate (CdIn2O4), zinc stannate (Zn2SnO4 and ZnSnO3), and zinc indium oxide (Zn2In2O5).

66. The barrier stack of claim 61, wherein the nanoparticles comprise carbon nanotubes.

67. The barrier stack of claim 66, wherein the amount of carbon nanotubes present is about 0.01% to about 10% of the total weight of nanoparticles present in the sealing layer.

68. The barrier stack of claim 61, wherein the sealing layer comprises carbon nanotubes and metal oxide nanoparticles, the quantity of metal oxide nanoparticles present being between 500 to 15000 times (by weight) the quantity of carbon nanotubes present.

69. The barrier stack of claim 61, further comprising inert nanoparticles capable of obstructing the permeation of moisture and/or oxygen through the defects present in the barrier layer.

70. The barrier stack of claim 69, wherein the inert nanoparticles comprise a material selected from the group consisting of gold, copper, silver, platinum, silica, wollastonite, mullite, monmorillonite, silicate glass, fluorosilicate glass, fluoroborosilicate glass, aluminosilicate glass, calcium silicate glass, calcium aluminum silicate glass, calcium aluminum fluorosilicate glass, titanium carbide, zirconium carbide, zirconium nitride, silicon carbide, or silicon nitride, metal sulfides, and a mixture or combination thereof.

71. The barrier stack of claim 61, wherein the size of the nanoparticles is smaller than the average diameter of defects present in the at least one barrier layer.

72. The barrier stack of claim 61, wherein when the oxygen and/or moisture sensitive article comprises an electroluminescent electronic component, the average size of the nanoparticles is less than one-half the characteristic wavelength of light produced by the electroluminescent electronic component.

73. The barrier stack of claim 61, wherein the sealing layer further comprises a polymeric binder, wherein the nanoparticles are distributed within the polymeric binder.

74. The barrier stack of claim 61, wherein the barrier layer comprises a material selected from indium tin oxide (ITO), TiAlN, SiO2, SiC, Si3N4, TiO2, HfO2, Y2O3, Ta2O5, and Al2O3.

75. The barrier stack of claim 61, further comprising a substrate for supporting the multilayer film.

76. The barrier stack of claim 75, wherein the multilayer film is orientated such that the sealing layer is arranged on the substrate.

77. The barrier stack of claim 75, wherein the substrate comprises a material selected from polyacetate, polypropylene, polyimide, cellophane, poly(1-trimethylsilyl-1-propyne, poly(4-methyl-2-pentyne), polyimide, polycarbonate, polyethylene, polyethersulfone, epoxy resins, polyethylene terepthalate, polystyrene, polyurethane, polyacrylate, and polydimethylphenylene oxide, styrene-divinylbenzene copolymers, polyvinylidene fluoride (PVDF), nylon, nitrocellulose, cellulose, glass, indium tin oxide, nano-clays, silicones, polydimethylsiloxanes, biscyclopentadienyl iron, and polyphosphazenes.

78. The barrier stack of claim 61, wherein the multilayer film is arranged on one surface of the substrate or wherein each multilayer film is arranged on each opposing surface of the substrate.

79. The barrier stack of claim 75, further comprising a planarising layer interposed between the substrate and the multilayer film.

80. The barrier stack of claim 61, further comprising a terminal layer for protecting the multilayer film.

81. The barrier stack of claim 80, wherein the terminal layer comprises an acrylic film.

82. The barrier stack of claim 81, wherein the acrylic film has distributed therein LiF and/or MgF2 particles.

83. An electronic device comprising an active component that is sensitive to moisture and/or oxygen, said active component being arranged within an encapsulation barrier stack according to claim 61.

84. The electronic device of claim 83, wherein the barrier stack forms a base substrate for supporting the reactive component.

85. The electronic device of claim 83, wherein the encapsulation barrier stack further comprises

a covering layer arranged proximally over the active component to form a proximal encapsulation, said reactive component being sandwiched between the covering layer and the encapsulation barrier stack.

86. The electronic device of claim 85, wherein the shape of the covering layer conforms to the external shape of the reactive component.

87. The electronic device of claim 83, wherein the encapsulation further comprises

a cover substrate attached to the base substrate by means of an adhesive layer, said adhesive layer being arranged at least substantially along the edge of the cover substrate for forming a rim-sealed enclosure around the reactive component.

88. The electronic device of claim 83, wherein the active component is arranged on a base substrate, and the encapsulation barrier stack forms an encapsulation layer over the reactive component that seals the reactive component against the base substrate.

89. The electronic device of claims 83, wherein the reactive component is selected from the group consisting of an Organic Light Emitting Device (OLED), charged-coupled device (CCD), and micro-electro-mechanical sensors (MEMS).

90. A method for the manufacture of an encapsulation barrier stack according to claim 61, comprising:

forming at least one barrier layer and at least one sealing layer on a surface for receiving the barrier stack,

wherein

forming the at least one sealing layer comprises mixing a polymerisable compound with a nanoparticle dispersion to form a sealing mixture, and polymerising the sealing mixture over the at least one barrier layer under vacuum.

91. The method of claim 90, further comprising

providing a substrate for supporting the barrier stack, wherein said at least one sealing layer is first formed on the substrate.

92. The method of claim 91, wherein the substrate comprises a barrier layer and/or polymer substrate.