FLEXIBLE PHOTOPATTERNED MASK FOR HIGH RESOLUTION ORGANIC LIGHT EMITTING DISPLAYS AND METHOD FOR MANUFACTURING SAME - Patent application

Abstract

The present invention relates to a method for fabricating a flexible photo-patterned mask, the method including: a) coating a photoresist composition on a substrate to form a photoresist film, b) exposing the photoresist film to light to pattern the photoresist film, c) developing the patterned photoresist film, and d) curing the developed photoresist film to form a patterned layer having a plurality of tapered openings.

Description

[Technical field]

[0001] The present invention relates to a flexible photo-patterned mask for use in the fabrication of high resolution organic light emitting displays and a method for manufacturing said photo-patterned mask. [Background technology]

[0002] Significant progress has been made in the field of flat panel displays. Flat panel displays, especially liquid crystal displays (LCDs), have started to appear on the market and have overtaken cathode ray tubes (CRTs). In recent years, display devices such as plasma display panels (PDPs), fluorescent displays (VFDs), field emission displays (FEDs), light emitting diodes (LEDs), and electroluminescent (EL) devices have been in fierce competition and have been improved in terms of visibility, color rendition, and fabrication processes.

[0003] Organic light-emitting displays (OLEDs) have attracted interest as flat-panel displays due to their space-saving design, among other advantages: they have a very small thickness, can be addressed in a matrix format, and can be driven even at low voltages below 15 V.

[0004] Metal masks are usually used in the fabrication of organic light-emitting displays to form the areas where organic light-emitting materials are to be deposited and the second electrode. In particular, metal masks are used to form RGB pixels in the manufacture of full-color organic light-emitting displays. The pattern resolution of the metal mask determines the resolution of the organic light-emitting display. Therefore, the resolution of the metal mask needs to be improved. The metal mask should also be well aligned with the substrate.

[0005] According to the prior art, a metal mask is fabricated by applying photoresist (PR) to a metal sheet, exposing the photoresist through a mask (or directly patterning without a mask using an exposure tool), developing the exposed photoresist to form a pattern, and wet etching the pattern to transfer the pattern to the metal sheet.

[0006] However, the width of the pattern is difficult to precisely control during wet etching due to the anisotropy of the etching, which limits the pattern resolution of the metal mask. Therefore, a technique using electroplating instead of wet etching has been proposed to manufacture metal masks with high-resolution patterns.

[0007] Although electroplating allows the production of metal masks with high-resolution patterns, it has the problem that it is difficult to control the slope of the sidewalls of the patterned openings formed in the metal mask, resulting in non-uniform deposition of organic light-emitting material. Specifically, if the slope of the sidewalls of the patterned openings in the metal mask is too vertical, a certain area below the opening will be in the shadow of the sidewalls of the opening. This shadowing prevents the organic light-emitting material from being smoothly supplied to a certain area below the opening during the deposition of the organic light-emitting material using the metal mask, leading to non-uniform deposition of the organic light-emitting material on the substrate. In an organic light-emitting display where the organic light-emitting material is not uniformly deposited, a high-precision pixel pattern is not formed, which leads to poor image quality and ultimately to failure to achieve high resolution. Summary of the Invention [Problem to be solved by the invention]

[0008] With this in mind, the present invention aims to provide a flexible photo-patterned mask that can replace the traditional metal masks used in processes for depositing organic light-emitting materials. The present invention also aims to provide a method for manufacturing said flexible photo-patterned mask. The present invention also contemplates providing a method for depositing organic light-emitting materials using said flexible photo-patterned mask. [Means for solving the problem]

[0009] One embodiment of the present invention provides a method for fabricating a flexible photo-patterned mask, comprising: a) coating a photoresist composition on a substrate to form a photoresist film; b) exposing the photoresist film to pattern the photoresist film; c) developing the patterned photoresist film; and d) curing the developed photoresist film to form a patterned layer having a plurality of tapered openings.

[0010] The photoresist composition may be a positive-acting composition that includes at least one resin selected from the group consisting of acrylic resins, imide resins, cardo resins, and silicone resins; a photoactive material; additives; and a solvent. The photoresist composition may be negative-acting and includes at least one resin selected from the group consisting of acrylic resins, imide resins, cardo resins, and silicone resins; a photocurable material; a photoinitiator; additives; and a solvent. The method may further include repeating steps a) through d) one or more times to form a plurality of patterned layers, each having a plurality of tapered openings.

[0011] The method of the present invention may further comprise forming a metal layer over the patterned layer, or under the layer, or both. The tapered opening may have a taper angle (θ) of 20° to 85°. The present invention also provides a flexible photo-patterned mask that includes a patterned layer having a plurality of tapered openings. The tapered opening may have a taper angle (θ) of 20° to 85°. The patterned layer may be provided in plurality.

[0012] The patterned layer may include a first patterned layer having a tapered opening and a second patterned layer having a tapered opening, and the tapered opening of the first patterned layer may have a taper angle (θ1) of 20° to 85°, and the tapered opening of the second patterned layer may have a taper angle (θ2) of 30° to 85°.

[0013] The patterned layers may include a first patterned layer having a tapered opening, a second patterned layer having a tapered opening, and a third patterned layer having a tapered opening, wherein the tapered opening of the first patterned layer may have a taper angle (θ1) of 20° to 85°, the tapered opening of the second patterned layer may have a taper angle (θ2) of 30° to 85°, and the tapered opening of the third patterned layer may have a taper angle (θ3) of 45° to 90°.

[0014] The flexible photo-patterned mask of the present invention may further include a metal layer formed over or under the patterned layer, or both. The present invention also provides a method for depositing an organic light emitting material, comprising: A) aligning a flexible photo-patterned mask including a patterned layer having a plurality of tapered openings onto a substrate for an organic light emitting display; and B) depositing an organic light emitting material onto the substrate through the plurality of tapered openings, the plurality of tapered openings decreasing in width approaching the substrate. Effect of the Invention

[0015] The flexible photo-patterned mask of the present invention is designed to adjust the width and / or taper angle of the patterned opening corresponding to the area where the organic light-emitting material is to be deposited, which prevents some areas of the bottom of the patterned opening from being shadowed by the sidewall of the patterned opening of the flexible photo-patterned mask when the organic light-emitting material is deposited using the flexible photo-patterned mask, and enables efficient deposition of the organic light-emitting material on the target area (pixel area).

[0016] In addition, the flexible photo-patterned mask of the present invention is made of organic or organic-inorganic materials so that the shape is well maintained during deposition, and therefore the flexible photo-patterned mask of the present invention is more stable in use than a metal mask, which does not maintain its shape for a long time.

[0017] Furthermore, the flexible photopatterned mask of the present invention is conveniently fabricated by photolithography using photoresist, which provides advantages in processing efficiency compared to conventional metal masks. Use of the flexible photo-patterned mask according to the present invention enables the fabrication of high resolution organic light emitting displays. [Brief description of the drawings]

[0018] [Figure 1] FIG. 1 illustrates a schematic diagram of a method for fabricating a flexible photo-patterned mask according to one embodiment of the present invention. [Diagram 2] FIG. 2 illustrates a schematic diagram of a method for manufacturing a flexible photo-patterned mask according to a further embodiment of the present invention. [Diagram 3] FIG. 3 is a cross-sectional view of a flexible photo-patterned mask according to one embodiment of the present invention. [Figure 4]FIG. 4 is a cross-sectional view of a flexible photo-patterned mask according to an exemplary embodiment of the present invention. [Diagram 5] FIG. 5 is a cross-sectional view of a flexible photo-patterned mask according to an exemplary embodiment of the present invention. [Figure 6] FIG. 6 is a cross-sectional view of a flexible photo-patterned mask according to an exemplary embodiment of the present invention. [Figure 7] FIG. 7 illustrates a schematic of a method for depositing an organic light-emitting material according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] It should be understood that the terms and words used in this specification and the claims should not be construed as having ordinary, dictionary meanings, but should be construed as having meanings and concepts corresponding to the spirit of the present invention in light of the principle that an inventor can appropriately define the concepts of terms and words in order to best describe his / her invention.

[0020] The present invention is directed to a flexible photo-patterned mask that is fabricated by photolithography and is designed to allow adjustment of the taper angle of the patterned openings and the widths of the top and bottom of the patterned openings. The flexible photo-patterned mask and the method of fabricating the flexible photo-patterned mask according to the present invention will be described in detail with reference to the accompanying drawings.

[0021] The flexible photo-patterned mask of the present invention can be manufactured by photolithography. Specifically, the present invention provides a method for manufacturing a flexible photo-patterned mask, including: a) coating a photoresist composition on a substrate to form a photoresist film; b) exposing the photoresist film to pattern the photoresist film; c) developing the patterned photoresist film; and d) curing the developed photoresist film to form a patterned layer having a plurality of tapered openings.

[0022] In step a), a photoresist film is formed using a photoresist composition. Depending on the type of photoresist composition, the flexible photopatterned mask may be fabricated by the process shown in Figure 1 or Figure 2. Specifically, Figure 1 shows the case where the photoresist composition is a positive type, and Figure 2 shows the case where the photoresist composition is a negative type.

[0023] A positive photoresist composition may include a resin, a photoactive material, additives, and a solvent. Specifically, the resin may be selected from the group consisting of acrylic resin, imide resin, cardo resin, silicone resin, and mixtures thereof. The resin may be a silicone resin (polysiloxane copolymer) having a weight average molecular weight of 2,000 to 200,000 (particularly 2,000 to 100,000) and an acid value of 10 to 200 KOHmg / g (particularly 10 to 150 KOHmg / g). The use of silicone resin facilitates the formation of tapered openings in flexible photopatterned masks.

[0024] The photoactive material refers to a material that reacts with light. The photoreactive material is not particularly limited and may be any photoactive material commonly known in the resist field. Specifically, the photoactive material may be selected from the group consisting of photoacid compounds (PACs), photoacid generators (PAGs), photobase generators (PBGs), and mixtures thereof.

[0025] The additive is not particularly limited and may be any additive commonly known in the art. Specifically, the additive may be selected from the group consisting of a crosslinking agent, a surfactant, an adhesion promoter, a photosensitizer, a heat stabilizer, a photocuring accelerator, an antioxidant, a light stabilizer, an antifoaming agent, and mixtures thereof.

[0026] The solvent is not particularly limited and may be an organic solvent generally known in the art. Specifically, the solvent may be selected from the group consisting of acetate-based solvents, ether-based solvents, glycol-based solvents, ketone-based solvents, alcohol-based solvents, carbonate-based solvents, and mixtures thereof.

[0027] Negative photoresist compositions may include a resin, a photocurable material, a photoinitiator, additives, and a solvent.

[0028] Specifically, the resin may be selected from the group consisting of acrylic resin, imide resin, cardo resin, silicone resin, and mixtures thereof. The resin may be a silicone resin (polysiloxane copolymer) having a weight average molecular weight of 2,000 to 200,000 (particularly 2,000 to 100,000) and an acid value of 10 to 200 KOHmg / g (particularly 10 to 150 KOHmg / g). The use of silicone resin facilitates the formation of tapered openings in flexible photopatterned masks.

[0029] The photocurable material may be a photocurable compound having one or more ethylenically unsaturated bonds. Specifically, the photocurable material may be a monomer, such as ethylene glycol diacrylate, ethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, triethylene glycol dimethacrylate, tetraethylene glycol diacrylate, tetraethylene glycol dimethacrylate, butylene glycol dimethacrylate, propylene glycol diacrylate, propylene glycol dimethacrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, tetramethylolpropane tetraacrylate, tetramethylolpropane tetramethacrylate, pentaerythritol triacrylate, pentaerythritol tetra ... dipentaerythritol dimethacrylate, pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, dipentaerythritol pentaacrylate, dipentaerythritol pentamethacrylate, dipentaerythritol hexaacrylate, dipentaerythritol hexamethacrylate, 1,6-hexanediol diacrylate, 1,6-hexanediol dimethacrylate, and cardo epoxy diacrylate; polyfunctional (meth)acrylic monomers, such as polycompounds of the above monomers (e.g., polyethylene glycol diacrylate); oligomers of the above monomers; compounds other than the photocurable monomers having one or more ethylenically unsaturated bonds; and mixtures thereof.

[0030] The photoinitiator is not particularly limited and may be any photoinitiator commonly known in the art. Specifically, the photoinitiator may be selected from the group consisting of oxime ester compounds, biimidazole compounds, benzoin compounds, acetophenone compounds, benzophenone compounds, α-diketone compounds, polynuclear quinone compounds, phosphine compounds, triazine compounds, and mixtures thereof.

[0031] The additive is not particularly limited and may be any additive known in the art. Specifically, the additive may be selected from the group consisting of a crosslinking agent, a photoacid generator, a sensitizer, a thermal acid generator, a surfactant, an adhesion promoter, a thermal stabilizer, a photocuring accelerator, an antioxidant, a light stabilizer, an antifoaming agent, and mixtures thereof.

[0032] The solvent is not particularly limited and may be an organic solvent generally known in the art. Specifically, the solvent may be selected from the group consisting of acetate-based solvents, ether-based solvents, glycol-based solvents, ketone-based solvents, alcohol-based solvents, carbonate-based solvents, and mixtures thereof.

[0033] The photoresist composition is coated on a substrate 2 to form a photoresist film 1 (step a). The photoresist composition may be coated (or deposited) on the substrate by any suitable method commonly known in the art. The substrate 2 may be made of various materials. Specifically, the substrate 2 may be a glass substrate or a plastic film.

[0034] In step b), the photoresist film 1 is patterned. Specifically, a patterned photomask 3 is placed on the photoresist 1, and energy is applied to the photoresist film to expose the photoresist film.

[0035] Specifically, the energy applied to the photoresist film 1 may be light energy such as visible light energy, infrared light energy, or ultraviolet light energy; electromagnetic energy due to electromagnetic waves of various frequencies; electric energy due to current or voltage; magnetic energy due to magnetic force or magnetic field; or particle energy due to protons, neutrons, electron beams, or ion beams.

[0036] A micropattern of several hundred micrometers or less can be formed on the patterned photomask 3. Instead of the photomask 3, a digital micromirror device may be used.

[0037] To prevent the diffusion of free radicals during the photoreaction and to form high-resolution microscale patterns, the photoresist film 1 may be patterned by optofluidic maskless lithography (OFML).

[0038] The method may include heating and drying (post-exposure bake) to control the diffusion of free radicals and acidic and basic active materials remaining in the photoresist film 1 after exposure.

[0039] In step c), the photoresist film 1 is developed to selectively remove the portions of the photoresist film that have undergone photoreaction after exposure or the portions of the photoresist film that have not undergone photoreaction, thereby leaving only the portions 1' of the photoresist film. The development is carried out using a developer. Specifically, the developer may be an alkaline aqueous solution.

[0040] In step d), the developed photoresist film 1' is cured to form a patterned layer 1a having a plurality of tapered openings (O). A tapered opening (O) can be defined as a hole passing through the photoresist film 1, the width of which gradually increases or decreases (forming a sloping surface) in the thickness direction of the photoresist film 1.

[0041] The opening (O) is due to the property of the photoresist composition that facilitates adjustment to the width and / or taper angle of the opening (O) of the patterned layer of the flexible photo-patterned mask. That is, the flexible photo-patterned mask of the present invention is simply fabricated by photolithography so that the width and / or taper angle of the patterned opening can be adjusted. In contrast, the conventional metal mask is fabricated through various complicated processes such as wet etching, plating, and multiple exposures.

[0042] Due to the shape of the tapered opening (O), an inclined surface is formed in the opening (O). The taper angle (θ) can be defined as the angle between the substrate 1 or the ground surface and the inclined surface. Here, the taper angle (θ) may be less than 90°. Considering the deposition efficiency of the organic light-emitting material (to prevent a certain area of ​​the bottom of the opening from being in the shadow of the sidewall of the opening), the taper angle (θ) may be 20° to 85° (particularly 25° to 70°).

[0043] The curing (hard baking) of the developed photoresist film 1' in step d) is not limited to any particular condition, for example, the curing temperature may be 200 to 250° C., and the curing time may be 20 to 60 minutes.

[0044] The method of the present invention may further include repeating steps a)-d) one or more times (particularly two or three times) to form a plurality of patterned films 1a, each having a plurality of tapered openings (O). For example, steps a)-d) are performed to form a first patterned layer, and steps a)-d) are repeated to form a second patterned layer and a third patterned layer formed sequentially on the first patterned layer. Here, the photoresist compositions used in step a) to form the first to third patterned layers may be the same or different from each other.

[0045] The method of the present invention may further include forming a metal layer on and / or under the patterned layer 1a formed in step d). The process for forming the metal layer is not particularly limited and may be atomic layer deposition (ALD), thermal evaporation, electroplating, or metal deposition. When the patterned layer has a multi-layer structure consisting of a first patterned layer 1a, a second patterned layer 1b, and a third patterned layer 1c, the metal layer may be formed on and / or under the outermost patterned layer.

[0046] The flexible photo-patterned mask of the present invention provides a solution to the problem of conventional metal or photomasks in that the vertical sidewalls of the patterned openings cast shadows on certain areas below the patterned openings, making it difficult to deposit organic light-emitting materials uniformly, i.e., the patterned openings of the flexible photo-patterned mask of the present invention are sloped, as will be described in detail below with reference to the corresponding figures.

[0047] 3, the flexible photo-patterned mask of the present invention includes a patterned layer 1a having a plurality of tapered openings (O), which can be defined as holes that penetrate the photoresist film 1 and whose width gradually increases or decreases (forming a sloping surface) in the thickness direction of the photoresist film 1.

[0048] For the tapered opening (O), an inclined surface is formed in the opening (O). The taper angle (θ) can be defined as the angle between the ground surface and the inclined surface. Here, the taper angle (θ) may be less than 90°. Considering the deposition efficiency of the organic light-emitting material (to prevent a certain area of ​​the lower part of the opening from being in the shadow of the sidewall of the opening), the taper angle (θ) may be 20° to 85° (particularly 25° to 70°).

[0049] The widths of the upper (Φ1) and lower (Φ2) of each opening (O) are in the range of 1 to 100 μm and may be different from each other (specifically, Φ1 is preferably smaller than Φ2 (Φ1<Φ2)). The thickness (δ) of the patterned layer 1a having a plurality of tapered openings (O) may be between 1 and 100 μm, in particular between 5 and 80 μm.

[0050] 4 and 5, the flexible photo-patterned mask of the present invention may include multiple patterned layers. Specifically, the flexible photo-patterned mask of the present invention includes a first patterned layer 1a having multiple tapered openings, a second patterned layer 1b formed on the first patterned layer 1a, and a third patterned layer 1c formed on the second patterned layer 1b.

[0051] The taper angle (θ1) of the tapered opening of the first patterned layer 1a may be 20° to 85°, the taper angle (θ2) of the tapered opening of the second patterned layer 1b may be 30° to 85°, and the taper angle (θ3) of the tapered opening of the third patterned layer 1c may be 45° or more and less than 90°.

[0052] The thickness (δ1) of the first patterned layer 1a and the thickness (δ2) of the second patterned layer 1b may be 1 to 100 μm, particularly 5 to 80 μm, and the thickness (δ3) of the third patterned layer 1c may be 1 nm to 100 μm, particularly 1 nm to 50 μm.

[0053] When the taper angles (θ1, θ2, θ3) and / or thicknesses (δ1, δ2, δ3) of the first patterned layer 1a, the second patterned layer 1b, and the third patterned layer 1c are within the above respective ranges, shadowing by the sidewalls of the opening is minimized and high deposition efficiency of the organic light-emitting material is obtained.

[0054] Considering the deposition efficiency of the organic light-emitting material, it is preferable that the bottom width (Φ1) of the first patterned layer 1a, the bottom width (Φ2) of the second patterned layer 1b, and the bottom width (Φ3) of the third patterned layer 1c are within the range of 1 to 100 μm and satisfy the relationship Φ1<Φ2<Φ3. The stack of multiple patterned layers of the flexible photo-patterned mask of the present invention allows control over the width and / or taper angle of the openings.

[0055] 6, the flexible photo-patterned mask of the present invention may further include a metal layer 4 on or under the patterned layer 1a, or both. Here, when the patterned layer has a multi-layer structure consisting of a first patterned layer 1a, a second patterned layer 1b, and a third patterned layer 1c, the metal layer may be formed on or under the outermost patterned layer, or both.

[0056] The metal layer 4 may have a thickness of 1 nm to 100 μm. The metal layer 4 may be formed from a metal generally known in the art. The formation of the metal layer 4 ensures high mechanical strength of the flexible photopatterned mask and is effective in blocking moisture and oxygen. The present invention also provides a method for depositing an organic light-emitting material using a flexible photo-patterned mask. Specifically, the method includes A) aligning a flexible photo-patterned mask including a patterned layer having a plurality of tapered openings onto a substrate for an organic light-emitting display, and B) depositing an organic light-emitting material onto the substrate through the plurality of tapered openings, which will be described in detail below with reference to the corresponding figures.

[0057] 7, first, before depositing an organic light-emitting material on a substrate (20) for an organic light-emitting display, a flexible photo-patterned mask including a patterned layer having a plurality of tapered openings (O) is aligned with the substrate. Here, the flexible photo-patterned mask (10) is aligned such that the smaller width (particularly the smallest width) of the tapered openings (O) faces the substrate (20). That is, the tapered openings (O) have a smaller width (Φ1<Φ2) as they approach the substrate (20).

[0058] By using a flexible photopatterned mask with apertures (O) of controlled width (Φ) and taper angle (θ), the shadowing by the aperture sidewalls is minimized and the deposition efficiency of the organic light-emitting material is increased, which enables the fabrication of organic light-emitting displays with high resolution and improved pixel uniformity.

[0059] An organic light emitting material (30) is then deposited onto the substrate (20) through the tapered openings (O). The deposition may be performed by any suitable method generally known in the art. As a result of the deposition, an array of pixels (areas (30') where organic light emitting material is deposited) is formed on the substrate (10). The substrate 20 may be any substrate commonly known in the art (eg, a glass substrate or a flexible substrate such as a polyimide substrate).

[0060] Organic light-emitting materials can be efficiently deposited in the pixel areas through the tapered openings (O), enabling the fabrication of organic light-emitting displays with high resolution and improved pixel uniformity.

[0061] The present invention will be described in more detail with reference to the following examples. However, these examples are provided for illustrative purposes only, and the scope of the present invention is not limited thereto. It will be apparent to those skilled in the art that various modifications and variations can be made without departing from the scope and spirit of the present invention. (Additional Note) The invention of the present disclosure includes the following aspects. Section 1: A method for making a flexible optical patterned mask, comprising: a) coating a photoresist composition on a substrate to form a photoresist film; b) exposing the photoresist film to pattern the photoresist film; c) developing the patterned photoresist film; and d) curing the developed photoresist film to form a patterned layer having a plurality of tapered openings. Section 2: Item 2. The method of item 1, wherein the photoresist composition is a positive-working composition comprising at least one resin selected from the group consisting of acrylic resins, imide resins, cardo resins, and silicone resins; a photoactive material; additives; and a solvent. Section 3: Item 2. The method according to item 1, wherein the photoresist composition is a negative type photoresist composition comprising at least one resin selected from the group consisting of acrylic resins, imide resins, cardo resins, and silicone resins; a photocurable material; a photoinitiator; additives; and a solvent. Section 4: Item 1. The method of item 1, further comprising repeating steps a)-d) one or more times to form a plurality of patterned layers, each having a plurality of tapered openings. Section 5: Item 10. The method of item 1, further comprising forming a metal layer over the patterned layer, or under the layer, or both. Item 6: Item 2. The method according to item 1, wherein the tapered opening has a taper angle (θ) of 20° to 85°. Section 7: A flexible photo-patterned mask including a patterned layer having a plurality of tapered openings. Section 8: Item 8. The flexible photo-patterned mask according to item 7, wherein the tapered opening has a taper angle (θ) of 20° to 85°. Section 9: Item 8. The flexible photo-patterned mask according to item 7, wherein the patterned layer is provided in a plurality of layers. Section 10: The patterned layers include a first patterned layer having a tapered opening and a second patterned layer having a tapered opening, the tapered opening of the first patterned layer having a taper angle (θ 1 ), and the tapered openings of the second patterned layer have a taper angle (θ 2 Item 8. The flexible photopatterned mask according to item 7, having a Section 11: The patterned layers include a first patterned layer having a tapered opening, a second patterned layer having a tapered opening, and a third patterned layer having a tapered opening, the tapered opening of the first patterned layer having a taper angle (θ) of 20° to 85°. 1 ), and the tapered openings of the second patterned layer have a taper angle (θ 2 ), and the tapered openings of the third patterned layer have a taper angle (θ 3 Item 8. The flexible photopatterned mask according to item 7, having a Section 12: Item 8. The flexible photo-patterned mask of item 7, further comprising a metal layer formed on or under the patterned layer, or both. Section 13: A method for depositing organic light-emitting material, comprising: A) aligning a flexible photo-patterned mask including a patterned layer having a plurality of tapered openings onto a substrate for an organic light-emitting display; and B) depositing organic light-emitting material onto the substrate through the plurality of tapered openings, the plurality of tapered openings decreasing in width approaching the substrate. EXAMPLES

[0062] A negative photoresist composition was prepared by mixing 7.5 g of resin (Takoma, TSR-SB5K), 0.7 g of photoinitiator (Takoma, TPM-P370), 2.1 g of photocurable material (DPHA), 0.05 g of adhesion promoter (KBM403), 0.1 g of surfactant (FZ2122), and 10.5 g of solvent (PGMEA). This photoresist composition was spin-coated on a glass substrate to form a photoresist film with a thickness of 12 μm. Then, a photomask with a pattern (size: 1-50 μm) was placed on the photoresist film. The photoresist film was exposed to an ultra-high pressure mercury lamp and developed in a spray type at 23°C for 60 seconds using 0.04% potassium hydroxide solution as a developer. The developed photoresist film was then hard baked at 250 °C for 60 min to fabricate a flexible photopatterned mask containing a patterned layer (10 μm thick) with multiple tapered openings (taper angle 40°). EXAMPLES

[0063] A positive photoresist composition was prepared by mixing 7.5 g of resin (Takoma, TSR-SB10K), 3 g of photoactive material (diazonaphthoquinone compound), 5 g of solvent (PGMEA), 0.15 g of adhesion promoter (KBM403), and 0.2 g of surfactant (FZ2122). This photoresist composition was spin-coated on a glass substrate and pre-baked to form a photoresist film with a thickness of 12 μm. Then, a photomask with a pattern (size: 1-50 μm) was placed on the photoresist film. The photoresist film was exposed to an ultra-high pressure mercury lamp and developed with 2.38% tetramethylammonium hydroxide (TMAH) as a developer in a spray type at 23°C for 60 seconds. The developed photoresist film was then hard baked at 250 °C for 60 min to fabricate a flexible photopatterned mask containing a patterned layer (10 μm thick) with multiple tapered openings (taper angle 50°). EXAMPLES

[0064] Each of the flexible photo-patterned masks prepared in Example 1 and Example 2 was aligned on a glass substrate so that the smallest width of the opening (O) of the patterned layer faced the substrate. Then, an organic light-emitting material was vacuum-deposited on the glass substrate through the opening of the patterned layer.

Claims

1. a) coating a photoresist composition on a substrate to form a photoresist film; b) exposing the photoresist film to light to pattern the photoresist film; c) developing the patterned photoresist film; and d) curing the developed photoresist film to form a patterned layer having a plurality of tapered openings, the tapered openings having a top width (Φ １ ) is the lower width (Φ ２ 1. A method for manufacturing a flexible photo-patterned mask, the method comprising: The patterned layers include a first patterned layer having a tapered opening, a second patterned layer having a tapered opening, and a third patterned layer having a tapered opening, and the first patterned layer has a thickness (δ １ ) is between 1 μm and 100 μm, and the thickness (δ ２ ) is between 1 μm and 100 μm, and the thickness (δ ３ ) is between 1 nm and 100 μm.

2. 10. The method of claim 1, wherein the photoresist composition is a positive-acting composition comprising at least one resin selected from the group consisting of acrylic resins, imide resins, cardo resins, and silicone resins; a photoactive material; additives; and a solvent.

3. 10. The method of claim 1, wherein the photoresist composition is a negative-acting composition comprising at least one resin selected from the group consisting of acrylic resins, imide resins, cardo resins, and silicone resins; a photocurable material; a photoinitiator; additives; and a solvent.

4. The method of claim 1 , further comprising forming a metal layer over the patterned layer, or under the patterned layer, or both.

5. The method of claim 1 , wherein the tapered opening has a taper angle (θ) between 20° and 85°.

6. The tapered opening of the first patterned layer has a taper angle (θ １ ) and the tapered opening of the second patterned layer has a taper angle (θ ) of 30° to 85°. ２ ), and the tapered opening of the third patterned layer has a taper angle (θ ) of 45° or more and less than 90°. ３ 2. The method of claim 1 , comprising:

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