Shadow mask and method for manufacturing the same

Abstract

The present invention relates to a method for manufacturing a shadow mask, comprising the steps of: forming a conductive layer on a base substrate; laminating a photoresist on the conductive layer and patterning it in a manner corresponding to a mask pattern; performing electroforming on areas other than the patterned photoresist to form a mask sheet; patterning the base substrate and the conductive layer so that the mask pattern is exposed to form a mask frame; and performing phototreatment or heat treatment before or after forming the mask frame or during the process of forming the mask frame to strengthen the bonding force between the mask sheet and the conductive layer.

Description

Technical Field

[0001] The present invention relates to a shadow mask used for manufacturing an organic light-emitting device having a micrometer-scale ultra-small mask pattern and a method for manufacturing the same.

Background Art

[0002] An organic light-emitting diode (OLED) is a self-luminous element that utilizes an electroluminescence phenomenon in which light is emitted when an electric current flows through a fluorescent organic compound. Since no backlight is required to add light to a non-light-emitting element, a lightweight and thin flat panel display device can be manufactured.

[0003] The organic light-emitting device has a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, an electron injection layer, etc., which are the remaining constituent layers except for the anode and cathode electrodes, and are made of an organic thin film. Such an organic thin film can be formed on a substrate by a vacuum evaporation method or the like.

[0004] The vacuum evaporation method comprises placing a substrate in a vacuum chamber, aligning a shadow mask having a certain pattern formed thereon with the substrate, and then heating an evaporation source containing a deposition material to evaporate the deposition material from the evaporation source and deposit it on the substrate.

[0005] Recently, as displays using organic light-emitting diodes (OLEDs) have evolved to high resolutions, the mask pattern of the shadow mask for realizing this must also be fabricated in an ultra-small size in the micrometer unit. Therefore, various studies have been made on the technology for manufacturing a shadow mask having a fine pattern.

[0006] Among such manufacturing technologies, a technology for manufacturing a mask sheet by electroforming a metal material such as Invar (iron-nickel alloy) has been proposed. Invar is an alloy of iron and nickel and has the advantage of small thermal deformation during evaporation due to its small coefficient of thermal expansion.

[0007] According to this, after forming a very thin mask sheet by electroforming, the mask sheet must be separated from the conductive layer that was used as an electrode. However, this separation process can cause damage such as tearing or wrinkling of the mask sheet, making the manufacturing process difficult. [Overview of the project] [Problems that the invention aims to solve]

[0008] The present invention aims to solve the aforementioned problems and provides a shadow mask and a method for manufacturing the same that can be manufactured without damage such as tearing or wrinkling of the mask sheet when manufacturing a shadow mask for manufacturing an organic light-emitting element having an ultra-small mask pattern on a micron scale using electroforming plating, and that minimizes the peeling of at least a portion of the mask sheet from the conductive layer during the manufacturing and usage processes.

[0009] The technical problems that this invention aims to solve are not limited to those mentioned above, and any other technical problems not mentioned can be clearly understood by a person with ordinary skill in the art to which this invention pertains from the following description. [Means for solving the problem]

[0010] One embodiment of the present invention discloses a method for manufacturing a shadow mask, comprising the steps of: forming a conductive layer on a base substrate; laminating a photoresist on the conductive layer and patterning it in a manner corresponding to a mask pattern; performing electroforming on areas other than the patterned photoresist to form a mask sheet; patterning the base substrate and the conductive layer so that the mask pattern is exposed to form a mask frame; and performing phototreatment or heat treatment before or after forming the mask frame or during the process of forming the mask frame to strengthen the bonding force between the mask sheet and the conductive layer.

[0011] Furthermore, the aforementioned photoprocessing may include laser welding using laser light.

[0012] Furthermore, the laser welding can be performed on the outer region of the mask pattern, which is provided in multiple locations on the mask sheet.

[0013] Furthermore, multiple welding points for the laser welding can be set so as to be separated at regular intervals along the outer edge of the mask pattern.

[0014] Furthermore, the laser welding may be performed such that the mask frame and the mask sheet are welded together.

[0015] Furthermore, multiple welding points for the laser welding can be set along the outer and inner circumferences of the mask frame, spaced apart at regular intervals.

[0016] Furthermore, when forming the mask frame, support ribs may be formed together with the multiple mask patterns, and the laser welding may be performed such that the support ribs and the mask sheet are welded together.

[0017] Furthermore, the heat treatment may include a heating process performed in a heating furnace or a resistance welding process in which current and pressure are applied to the joint.

[0018] Furthermore, the heat treatment may be performed after removing the photoresist from the mask sheet.

[0019] Furthermore, before forming the conductive layer, an additional step may be performed: forming an adhesive layer to strengthen the adhesion between the base substrate and the conductive layer.

[0020] Furthermore, the conductive layer may contain copper, and the adhesive layer may contain titanium.

[0021] Further, the conductive layer may be formed of a conductive metal doped with impurities so as to strengthen the adhesive force between the base substrate and the conductive layer.

[0022] Further, before forming the conductive layer, a step of forming an insulating film used as an etch stop layer during patterning of the base substrate may be additionally performed.

[0023] Further, the insulating film may be formed of a material containing silicon oxide.

[0024] On the other hand, according to another embodiment of the present invention, a mask frame, a mask sheet made of an Invar material supported by the mask frame, a mask pattern formed on the mask sheet for selectively passing a deposition material during a deposition process, and an alignment mark formed in an outer peripheral region of the mask sheet for alignment with a deposition target substrate are included. The alignment mark is formed through the mask sheet so as to pass light emitted from a light source of an alignment apparatus, and includes a window hole for acquiring an image of the alignment key of the substrate, and a key hole formed through at least one side of the window hole for relative alignment with the alignment key. A shadow mask using Invar is disclosed.

[0025] Further, the window hole has a polygonal shape, and the key hole may be formed on at least one side of each side of the polygon.

[0026] Further, the alignment key has a form in which a plurality of pattern keys are arranged at regular intervals, and the key hole may include a plurality of pattern holes formed so as to correspond to the form and position of the pattern key.

[0027] Further, a through hole may be formed in the mask frame at a position corresponding to the alignment mark.

[0028] Furthermore, the substrate may have additional auxiliary alignment keys formed thereon, and the alignment marks may further include auxiliary keyholes formed at positions corresponding to the auxiliary alignment keys.

[0029] On the other hand, according to yet another embodiment of the present invention, a method for manufacturing a shadow mask is disclosed, which includes the steps of: forming a conductive layer on a base substrate; laminating a photoresist on the conductive layer and patterning the photoresist in a manner corresponding to the mask pattern, the window holes and the keyholes; performing electroforming on areas other than the patterned photoresist to form a mask sheet; and patterning the base substrate and the conductive layer so that the mask pattern, the window holes and the keyholes are exposed to form a mask frame.

[0030] Furthermore, when patterning the base substrate for exposing the mask pattern, the window hole and the through-hole for exposing the keyhole can be patterned together.

[0031] Furthermore, before forming the conductive layer, an adhesive layer can be formed to strengthen the adhesion between the base substrate and the conductive layer.

[0032] Furthermore, the conductive layer may contain copper, and the adhesive layer may contain titanium.

[0033] Furthermore, to enhance the adhesion between the base substrate and the conductive layer, the conductive layer may be formed from a conductive metal doped with impurities.

[0034] Furthermore, before forming the conductive layer, an additional step may be performed: forming an insulating film used as an etching stop layer during patterning of the base substrate.

[0035] Furthermore, the insulating film may be formed from a material containing silicon oxide. [Effects of the Invention]

[0036] According to embodiments of the present invention, in manufacturing a shadow mask for manufacturing an organic light-emitting element having an ultra-small mask pattern on a micron scale using electroforming, the shadow mask can be manufactured without a step of separating the mask sheet by forming a mask sheet through electroforming and then patterning a base substrate to form a mask frame. This has the effect of preventing damage such as tearing or wrinkling of the mask sheet during the shadow mask manufacturing process.

[0037] Furthermore, according to embodiments of the present invention, strengthening the bonding force between the mask sheet and the conductive layer through phototreatment or heat treatment minimizes the peeling of the mask sheet from the conductive layer during the etching process of the base substrate or the use process of the shadow mask (e.g., cleaning of the mask).

[0038] Furthermore, according to embodiments of the present invention, by using an insulating film as an etching stop layer during the process of forming a mask frame through patterning of the base substrate, it is possible to prevent damage to the mask sheet caused by the etching solution.

[0039] Furthermore, according to embodiments of the present invention, a shadow mask for manufacturing organic light-emitting elements having a micro-scale ultra-small mask pattern is provided, which has a new structure different from existing ones that can minimize alignment errors. Specifically, the present invention presents a new alignment mark structure in which the alignment marks on the mask sheet are divided into window holes and keyholes, so that the alignment keys on the substrate visible through the window holes and the keyholes on the mask sheet are aligned. This has the effect of providing an Invar material shadow mask that can minimize alignment errors because it is possible to align the alignment keys, which include multiple pattern keys, with the corresponding keyholes, which include multiple pattern holes.

[0040] Furthermore, according to the embodiment of the present invention, since a shadow mask can be manufactured without the step of separating the mask sheet, by forming a mask sheet through electroforming and then patterning the base substrate to form a mask frame, it has the effect of preventing damage such as tearing or wrinkling of the mask sheet during the manufacturing process of the shadow mask. [Brief explanation of the drawing]

[0041] [Figure 1] This is a cross-sectional view of a shadow mask for manufacturing an organic light-emitting element related to the present invention. [Figure 2] This is a flowchart illustrating a method for manufacturing a shadow mask according to one embodiment of the present invention. [Figure 3] This is a schematic manufacturing process diagram showing the steps up to the stage of forming the mask sheet shown in Figure 2. [Figure 4] This is a plan view of a shadow mask showing an example of a welding point in a laser welding process. [Figure 5] Figure 2 is a schematic manufacturing process diagram illustrating the steps involved in forming the mask frame. [Figure 6] These are bottom and cross-sectional views of a shadow mask showing other examples of welding points in a laser welding process. [Figure 7] These are bottom and cross-sectional views of a shadow mask, illustrating yet another example of a welding point in a laser welding process. [Figure 8] This is a manufacturing process diagram showing a method for manufacturing a shadow mask according to another embodiment of the present invention. [Figure 9] This is a manufacturing process diagram showing a method for manufacturing a shadow mask according to yet another embodiment of the present invention. [Figure 10] This is a manufacturing process diagram showing a method for manufacturing a shadow mask according to yet another embodiment of the present invention. [Figure 11] This is a cross-sectional view of a shadow mask for manufacturing an organic light-emitting element according to yet another embodiment of the present invention. [Figure 12] Figure 11 is a plan view of the shadow mask shown. [Figure 13] Figures 11 and 12 show plan views of the alignment marks of the shadow mask. [Figure 14] Figure 11 is a plan view of the alignment key of the substrate shown. [Figure 15] Figure 13 is a plan view showing the alignment marks of the shadow mask and the alignment keys of the substrate shown in Figure 14 aligned. [Figure 16] This is a plan view of alignment marks on a shadow mask according to another embodiment of the present invention. [Figure 17] This is a plan view of an alignment key for a substrate according to another embodiment of the present invention. [Figure 18] Figure 16 is a plan view showing the alignment marks of the shadow mask and the alignment keys of the substrate shown in Figure 17 aligned. [Figure 19] Figure 11 is a flowchart illustrating the manufacturing method of the shadow mask shown. [Figure 20] Figure 19 is a schematic diagram illustrating the manufacturing process for the shadow mask. [Figure 21] Figure 19 is a schematic diagram illustrating the manufacturing process for the shadow mask. [Modes for carrying out the invention]

[0042] Since the present invention can be subjected to various transformations and has various embodiments, specific embodiments will be illustrated in the drawings and described in detail in the detailed description. However, this is not intended to limit the present invention to specific embodiments, but should be understood to include all transformations, equivalents, or substitutes that fall within the spirit and technical scope of the present invention. In describing the present invention, if it is determined that a specific description of related prior art may obscure the gist of the present invention, such detailed description will be omitted.

[0043] The terms "First," "Second," etc., may be used to describe a variety of components, but such components should not be limited by these terms. The terms are used solely for the purpose of distinguishing one component from another.

[0044] The terms used in this application are used solely to describe specific embodiments and are not intended to limit the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, terms such as “includes” or “having” are intended to specify the existence of features, figures, stages, operations, components, parts, or combinations thereof described in the specification, and should be understood not to preemptively exclude the possibility of the existence or addition of one or more other features, figures, stages, operations, components, parts, or combinations thereof.

[0045] In the following, examples of embodiments of the shadow mask and its manufacturing method according to the present invention will be described in detail with reference to the accompanying drawings. When describing with reference to the accompanying drawings, identical or corresponding components will be given the same reference numerals, and redundant explanations will be omitted.

[0046] Figure 1 is a cross-sectional view of a shadow mask for manufacturing an organic light-emitting element related to the present invention.

[0047] As shown in Figure 1, the shadow mask 100 for organic light-emitting elements according to this embodiment includes a mask frame 10 and a mask sheet 20 supported by the mask frame 10.

[0048] The mask frame 10 is supported by a support structure such as a mask holder for vacuum deposition equipment and can have a configuration that supports the edge of the mask sheet 20. The mask frame 10 can have, for example, the form of a ring or donut with a through hole formed in the center, or the form of a mesh with multiple through holes in the center.

[0049] The mask sheet 20 is equipped with a mask pattern 22 for selectively passing the deposition material during the deposition process. The deposition material emitted from the evaporation source of the vacuum deposition apparatus passes through the mask pattern 22 and is deposited onto the substrate, thereby forming a pattern on the substrate corresponding to the mask pattern 22.

[0050] The mask sheet 20 may be formed from a material including invar (iron-nickel alloy). An invar thin film with a mask pattern 22 can be formed on the base substrate 31 by electroforming, and the shadow mask 100 can be manufactured by patterning the base substrate 31.

[0051] Figure 2 is a flowchart showing a method for manufacturing a shadow mask according to one embodiment of the present invention. Figure 3 is a schematic manufacturing process diagram showing the steps up to the stage of forming the mask sheet shown in Figure 2, Figure 4 is a plan view of the shadow mask showing the welding points in the laser welding process, and Figure 5 is a schematic manufacturing process diagram showing the stage of forming the mask frame shown in Figure 2.

[0052] Referring to Figures 2-5, the manufacturing method of the shadow mask 100 according to this embodiment will be described as follows: First, a conductive layer 40 is formed on the base substrate 31 (S11). The base substrate 31 can be made of a material that can be patterned by a semiconductor process; for example, a silicon base substrate 31 can be used. In such a case, a silicon wafer can be used as the base substrate 31.

[0053] A conductive metal such as copper (Cu) can be used as the conductive layer 40, and the conductive layer 40 can be formed through a vapor deposition process such as sputtering.

[0054] Before forming the conductive layer 40 on the base substrate 31, a corrosion protection layer 33 can be formed on the bottom surface of the base substrate 31 as shown in Figure 3(a), and an adhesive layer 35 can be formed on the top surface of the base substrate 31 as shown in Figure 3(b). However, the steps for forming the corrosion protection layer 33 and the adhesive layer 35 are optional and can be omitted if necessary.

[0055] Silicon nitride (SiN) is used as the etching protection layer 33. x Materials containing ) can be used, and a variety of other materials with low etching rates can also be used. The etching protection layer 33 has the function of protecting the edge region of the base substrate 31 from etching when the base substrate 31 is etched in the future, and this will be explained in detail later.

[0056] The adhesive layer 35 is intended to strengthen the adhesion between the base substrate 31 and the conductive layer 40 so that the conductive layer 40 does not easily peel off, and a metallic material containing titanium (Ti) may be used. The adhesive layer 35 can also be formed by a vapor deposition method such as sputtering.

[0057] After forming the adhesive layer 35 in this manner, a conductive layer 40 can be formed on the adhesive layer 35, as shown in Figure 3(c).

[0058] Alternatively, instead of using the adhesive layer 35, a conductive metal doped with impurities can be used as the conductive layer 40. For example, magnesium-doped copper can be used to form the conductive layer 40, thereby strengthening the bonding force between the conductive layer 40 and the base substrate 31.

[0059] Next, as shown in Figure 3(d), a photoresist 42 is laminated onto the conductive layer 40, and the photoresist 42 is patterned in a form corresponding to the mask pattern 22 (S12). Specifically, a photomask with pattern holes corresponding to the mask pattern 22 is placed on top of the photoresist 42 film, and the exposure and development process is carried out to perform the patterning. For reference, Figure 3(d) shows the form of the photoresist 42 after the patterning is completed through this process.

[0060] Next, as shown in Figure 3(e), electroforming is performed on the areas other than the patterned photoresist 42 to form a mask sheet 20 (S13). Electroforming is performed in a plating tank filled with a plating solution. By connecting a negative electrode terminal to the conductive layer 40 and a positive electrode terminal to the positive electrode body opposite it, and supplying power, the conductive layer 40 will be plated. As the plating solution, a plating solution containing nickel (Ni) ions and iron (Fe) ions, or a plating solution containing nickel (Ni) ions, iron (Fe) ions, and cobalt (Co) ions can be used.

[0061] Next, as shown in Figure 3(f), a phototreatment is performed to strengthen the bonding force between the mask sheet 20 and the conductive layer 40 (S14). Laser welding using laser light L can be performed as the phototreatment. In laser welding, the mask sheet 20 and the conductive layer 40 can be welded together by irradiating the mask sheet 20 with laser light L, which heats the focused portion while melting the space between them.

[0062] As shown in Figure 4, laser welding can be performed on the outer regions of multiple mask patterns 22 provided on the mask sheet 20. In areas where each mask pattern 22 is arranged adjacent to one another, laser welding can be performed along the partitioned area. In this case, the welding points P of the laser welding can be set to be spaced apart at regular intervals along the outer regions of the mask patterns 22.

[0063] However, in addition to this method, it is also possible to perform laser welding continuously to form a linear weld seam, and it may be possible to form welding points P at positions different from those exemplified in this embodiment, for example, around the mask sheet 20.

[0064] Next, as shown in Figure 3(g), the photoresist 42 is removed from the conductive layer 40, and the removed portion forms the mask pattern 22. At this time, the photoresist 42 can be removed through a wet process.

[0065] Next, as shown in Figure 5(a), the etching protection layer 33 is patterned to form a mask frame formation pattern 37 used for patterning the base substrate 31. The mask frame formation pattern 37 formed on the etching protection layer 33 provides a space for the etching solution to penetrate during the wet etching process, and the etching protection layer 33 functions to protect the edge region of the base substrate 31 from etching. Unlike this embodiment, the patterning of the etching protection layer 33 can also be performed after the step shown in Figure 3(a). On the other hand, in addition to patterning using the etching protection layer 33, patterning using photoresist may also be possible.

[0066] Next, the base substrate 31 and conductive layer 40 are patterned to form the mask frame 10 so that the mask pattern 22 is exposed (S15).

[0067] Specifically, as shown in Figure 5(b), the base substrate 31 is etched through the mask frame formation pattern 37 of the etching protective layer 33. At this time, wet etching using an etching solution may be used to etch the base substrate 31. Through such an etching process, an etched region 25 may be formed in the center of the base substrate 31.

[0068] Furthermore, when using the adhesive layer 35 as in this embodiment, the adhesive layer 35 is patterned as shown in Figure 5(c). In this case, the patterning can be carried out using an etching solution that selectively etches the adhesive layer 35.

[0069] Next, as shown in Figure 5(d), the conductive layer 40 is patterned through the mask frame formation pattern 37 of the etching protective layer 33. This can also be carried out by wet etching using an etching solution that selectively etches the conductive layer 40, and as a result, the formation of the mask frame 10 is completed and the fabrication of the shadow mask is completed. For reference, in this embodiment, wet etching is exemplified as the patterning method, but the patterning method is not limited to this, and patterning by dry etching may also be possible.

[0070] In this embodiment, the phototreatment to improve the bonding strength between the mask sheet 20 and the conductive layer 40 is shown to be performed after the stage indicated in Figure 3(e). However, such phototreatment can be performed before or after forming the mask frame 10, or during the process of forming the mask frame 10. In other words, it can be performed at any stage of the manufacturing process after the mask sheet 20 has been formed, specifically after stages 3(e) and 3(g), and after stages 5(a) to 5(d).

[0071] Figure 6 is a diagram showing another example of a welding point in a laser welding process, where (a) is a bottom view of the shadow mask and (b) is a cross-sectional view of the shadow mask.

[0072] Unlike the example shown in Figure 4, laser welding can also be performed so that the mask frame 10 and the mask sheet 20 are welded together. Specifically, the conductive layer 40 of the mask frame 10 and the mask sheet 20 are welded together. In this embodiment, after the formation of the mask frame 10 is completed, laser welding is performed by irradiating the mask frame 10 with laser light L from below toward the conductive layer 40.

[0073] As illustrated in Figure 6, multiple welding points P for laser welding can be set along the outer and inner circumferences of the mask frame 10, spaced apart at regular intervals.

[0074] Figure 7 is a diagram showing yet another example of a welding point in a laser welding process, where (a) is a bottom view of the shadow mask and (b) is a cross-sectional view of the shadow mask.

[0075] Figure 7 illustrates a structure in which a mask frame 10 is formed on the outer edge of the shadow mask 100, and support ribs 15 are formed in the partitioned regions between multiple mask patterns 22. The support ribs 15 can be formed at the same time as the mask frame 10, and can be formed by forming the mask frame formation pattern 37 of the etching protection layer 33 to correspond to the mask pattern 22 region. By forming the support ribs 15 in this way, the sagging development of the mask sheet 20 can be minimized.

[0076] In such cases, as shown in Figure 7, laser welding can be performed so that not only the mask frame 10 and the mask sheet 20 are welded, but also the space between the support rib 15 and the mask sheet 20. In this case, the welding point P between the support rib 15 and the mask sheet 20 can be set at at least one position on the support rib 15.

[0077] Figure 8 is a manufacturing process diagram showing a method for manufacturing a shadow mask according to another embodiment of the present invention.

[0078] In the embodiment described above, a phototreatment such as laser welding was performed to improve the bonding strength between the mask sheet 20 and the conductive layer 40, but it is also possible to perform a heat treatment instead, as in this embodiment. A heating process performed in a furnace can be used as the heat treatment.

[0079] Figure 8(a) is the same drawing as Figure 3(e), and shows the state in which the mask sheet 20 has been formed through electroforming.

[0080] Next, as shown in (b), after removing the photoresist 42, a heating process using heat H can be carried out as shown in (c). As a result, the conductive layer 40 may partially melt, thereby strengthening the bonding force with the layers located above and below it.

[0081] The heat treatment can be performed before or after forming the mask frame 10, or during the process of forming the mask frame 10, as in the embodiments described above. However, unlike the embodiments described above, if the heat treatment is performed with the photoresist 42 laminated, the photoresist 42 may be affected, such as being altered, which can affect subsequent processes. Therefore, it is preferable to perform the heat treatment after removing the photoresist 42 from the mask sheet 20.

[0082] In this embodiment, a heating process in a heating furnace was exemplified as the heat treatment method, but heat treatment through a resistance welding process in which current and pressure are applied to the joint area is also possible. In this case, the welding point can be set to be the same as the welding point in the laser welding process exemplified in the above-described embodiment.

[0083] Figures 9 and 10 are manufacturing process diagrams illustrating a method for manufacturing a shadow mask according to yet another embodiment of the present invention.

[0084] The manufacturing method of the shadow mask according to this embodiment will be described as follows: As shown in Figure 9(a), an insulating film 39 is formed on the upper surface of the base substrate 31, which is used as a stopping layer during patterning of the base substrate 31. Silicon oxide (SiO2) is used as the insulating film 39. y It is possible to use materials that include ), and a variety of other materials that can be used as etching stop layers are also available.

[0085] Next, as shown in (b), an etching protection layer 33 is formed on the bottom surface of the base substrate 31, and as shown in (c), an adhesive layer 35 is formed on the insulating film. The adhesive layer 35 serves to strengthen the adhesive force between the conductive layer 40 and the insulating film.

[0086] Next, as shown in (d), a conductive layer 40 is formed on the adhesive layer 35 (S11), and as shown in (e), a photoresist 42 is laminated on the conductive layer 40, after which patterning is performed. Then, as shown in (f), electroforming is performed on the areas other than the patterned photoresist 42 to form a mask sheet 20, and as shown in (g), the photoresist 42 is removed from the mask sheet 20.

[0087] Next, as shown in Figure 10(a), the etching protection layer 33 is patterned to form a mask frame formation pattern 37.

[0088] Then, as shown in (b), a phototreatment such as laser welding is performed on the mask sheet 20 and the conductive layer 40 to strengthen the bonding force between the mask sheet 20 and the conductive layer 40. This embodiment illustrates that a phototreatment is performed during the formation process of the mask frame 10, but it may also be possible to perform a heat treatment instead of a phototreatment.

[0089] Furthermore, as described above, the phototreatment and heat treatment can be performed not only at the stages exemplified in this embodiment, but also before, during, or after the formation of the mask frame 10.

[0090] Next, as shown in Figure 10(c), the base substrate 31 is etched through the mask frame formation pattern 37 of the etching protection layer 33. At this time, the insulating film 39 is used as a barrier that prevents the layer located above it from being arbitrarily etched, i.e., as an etching stopping layer. This prevents the mask sheet 20 from being damaged by the etching solution.

[0091] Next, as shown in (d) to (f), the insulating film 39, adhesive layer 35, and conductive layer 40 are sequentially patterned through the mask frame forming pattern 37 to form the mask frame 10, thereby completing the fabrication of the shadow mask.

[0092] Figure 11 is a cross-sectional view of a shadow mask for manufacturing an organic light-emitting element according to yet another embodiment of the present invention, showing it aligned with the substrate to be deposited, and Figure 12 is a plan view of the shadow mask shown in Figure 11. For reference, the cross-sectional view of the shadow mask in Figure 11 is a cut along the CC' line in Figure 12.

[0093] As shown in Figures 11 and 12, the shadow mask 1 for organic light-emitting elements according to this embodiment includes a mask frame 210 and a mask sheet 220 supported by the mask frame 210.

[0094] The mask frame 210 may be supported by a support structure such as a mask holder in a vacuum deposition system, and may have a configuration that supports the edges of the mask sheet 220. The mask frame 210 may have, for example, a ring or donut shape with a central hole 224 formed therein, or a mesh shape with multiple through holes in the center.

[0095] The mask sheet 220 is equipped with a mask pattern 222 for selectively passing the deposition material during the deposition process. The deposition material released from the evaporation source of the vacuum deposition apparatus passes through the mask pattern 222 and is deposited onto the substrate 2, thereby forming a pattern on the substrate 2 corresponding to the mask pattern 222. Multiple mask patterns 222 may be formed on the mask sheet 220, and each mask pattern 222 may have a configuration in which multiple fine pattern holes 223 are arranged, as shown in Figure 2.

[0096] The mask sheet 220 is formed from a material including Invar (iron-nickel alloy). An Invar thin film with a mask pattern 222 can be formed on the base substrate 241 by electroforming, and the shadow mask 1 can be manufactured by patterning the base substrate 241.

[0097] Alignment marks 230 for alignment with the substrate 2 to be deposited are provided in the outer region of the mask sheet 220. Through holes 212 may be formed in the mask frame 210 at positions corresponding to the alignment marks 230. Light emitted from the light source of the alignment apparatus passes through the through holes 212 and the alignment marks 230 to reach the alignment key 3 on the substrate 2, and the relative position adjustment between the substrate 2 and the shadow mask 1 is performed by using the image of the alignment key 3 and alignment marks 230 obtained through reflected light, thereby aligning the substrate 2 and the shadow mask 1.

[0098] On the other hand, in addition to this configuration, it may also be possible to form alignment marks 230 in the inner region of the mask frame 210 without forming through holes 212 in the mask frame 210.

[0099] Figure 13 is a plan view of the alignment marks of the shadow mask shown in Figures 11 and 12, and Figure 14 is a plan view of the alignment key of the substrate shown in Figure 11. Figure 15 is a plan view showing the alignment marks of the shadow mask shown in Figure 13 and the alignment key of the substrate shown in Figure 14 in an aligned state.

[0100] Referring to Figures 13-15, the alignment marks 230 include window holes 231 and keyholes 232 formed through the mask sheet 220.

[0101] The window hole 231 is formed through the mask sheet 220 to allow light from the light source of the alignment device to pass through, and is configured to acquire an image of the substrate 2 relative to the alignment key 3. For this purpose, the area through which the window hole 231 passes is configured to include the area where the alignment key 3 is located.

[0102] The keyhole 232 is formed through at least one side of the window hole 231 and is configured to perform relative alignment of the substrate 2 with the alignment key 3. The window hole 231 may have a polygonal shape, and the keyhole 232 may be formed on at least one side of each side of the polygon. In this embodiment, a structure is illustrated in which the keyhole 232 is formed on one side of two sides of a quadrilateral window hole 231.

[0103] The alignment key 3 may have a configuration in which a plurality of pattern keys 4 are arranged at regular intervals, and the keyhole 232 may include a plurality of pattern holes 234 formed to correspond to the configuration and position of the pattern keys 4. As illustrated in this embodiment, the plurality of pattern keys 4 and the plurality of pattern holes 234 may have the configuration of bars corresponding to each other, and the alignment error can be minimized through processing (e.g., averaging) of data such as the position and distance between the pattern keys 4 and pattern holes 234 at corresponding positions.

[0104] The alignment process between the substrate 2 and the shadow mask 1 is explained as follows: Light emitted from the light source of the alignment device passes through the through-hole 212 of the mask frame 210, then through the window hole 231 and keyhole 232 respectively, and reaches the region on the substrate 2 where the alignment key 3 is formed, where it is reflected. Through this reflected light, an image can be obtained in which the pattern key 4 is placed within the window hole 231, as shown in Figure 15. Alignment between the shadow mask 1 and the substrate 2 becomes possible through processing of the image data of the pattern key 4 and the pattern hole 234.

[0105] Figure 16 is a plan view of alignment marks on a shadow mask according to yet another embodiment of the present invention, and Figure 17 is a plan view of alignment keys on a substrate according to yet another embodiment of the present invention. Figure 18 is a plan view showing the alignment marks on the shadow mask shown in Figure 16 and the alignment keys on the substrate shown in Figure 17 aligned together.

[0106] According to this embodiment, auxiliary alignment keys 5 are additionally formed on the substrate 2, and auxiliary keyholes 236 are additionally formed on the mask sheet 220 at positions corresponding to the auxiliary alignment keys 5. The auxiliary alignment keys 5 and auxiliary keyholes 236 can be used as auxiliary means to set approximate positions prior to fine alignment of the substrate 2 and the mask.

[0107] The auxiliary alignment key 5 and the auxiliary keyhole 236 may have shapes such as figures, symbols, or signs that match each other. For example, the auxiliary alignment key 5 and the auxiliary keyhole 236 may have shapes such as rectangles and circles that match each other (see Figure 18), or shapes such as cross signs that match each other.

[0108] On the other hand, this embodiment illustrates a structure in which keyholes 232 are formed on one side of all four sides of a rectangular window hole 231, and auxiliary keyholes 236 are located outside the two vertices of the window hole 231.

[0109] When using the shadow mask 1 according to this embodiment, after performing primary alignment (rough alignment) of the substrate 2 and the shadow mask 1 through the auxiliary keyhole 236 and the auxiliary alignment key 5, secondary alignment (fine alignment) can be performed using the pattern key 4 and the pattern hole 234.

[0110] Figure 19 is a flowchart showing the manufacturing method of the shadow mask illustrated in Figure 11 of the present invention, and Figures 20 and 21 are manufacturing process diagrams illustrating the manufacturing method of the shadow mask according to Figure 19.

[0111] Referring to Figures 19-21, the manufacturing method of the shadow mask according to this embodiment will be described as follows: First, a conductive layer 246, which is used as an electrode for electroforming plating, is formed on the base substrate 241 (S21).

[0112] The process for forming the conductive layer 246 is shown in Figure 20(d). In this embodiment, an insulating film 242, which functions as an etching stop layer, and an etching protection layer 243, which provides etching protection during patterning of the base substrate 241, are additionally formed before forming the conductive layer 246. Forming the insulating film 242 and the etching protection layer 243 is an optional step, and it is also possible to immediately form the conductive layer 246 on the base substrate 241 without forming these.

[0113] Steps (a) to (c) in Figure 20 are described as follows: An insulating film 242 is formed on at least one surface of the base substrate 241. Materials that can be patterned by semiconductor processes can be used for both the base substrate 241 and the insulating film 242. For example, a silicon base substrate 241 can be used, in which case a silicon wafer can be used as the base substrate 241. Silicon oxide (SiO2) can be used as the insulating film 242. x It is possible to use materials that include ), and a variety of other materials that can be used as etching stop layers are also available.

[0114] In this embodiment, a base substrate 241 with insulating film 242 formed on both sides, i.e., a double-sided laminated substrate, is shown as an example. However, it is also possible to form the insulating film 242 only on one side of the base substrate 241, i.e., only on the upper surface of the base substrate 241.

[0115] Next, as shown in Figure 20(b), an etching protection layer 243 can be formed on the other side of the base substrate 241. Silicon nitride (SiN) can be used as the etching protection layer 243. x Materials containing ) can be used, and a variety of other materials with low etching rates can also be used. On the other hand, although this embodiment illustrates the formation of an etching protection layer 243 on the insulating film 242 on the lower surface of the base substrate 241, it is also possible to form the etching protection layer 243 on the lower surface of the base substrate 241 if the insulating film 242 is not formed on the lower surface of the base substrate 241.

[0116] Next, as shown in Figure 20(c), the etching protection layer 243 and the insulating film 242 are patterned to form a mask frame pattern 244 and a through-hole pattern 249 used for patterning the base substrate 241. The mask frame pattern 244 and the through-hole pattern 249 formed on the etching protection layer 243 and the insulating film 242 provide space for the etching solution to penetrate during the wet etching process, and the etching protection layer 243 protects the edge region of the base substrate 241 from etching.

[0117] In this embodiment, where an insulating film 242 is formed on the base substrate 241, the example shows patterning the etching protection layer 243 and the insulating film 242 to form a mask frame formation pattern 244 and a through-hole formation pattern 249. However, if the insulating film 242 is not formed, only the etching protection layer 243 is patterned to form the mask frame formation pattern 244 and the through-hole formation pattern 249. Also, if it is not necessary to position the alignment marks 230 in the inner region of the mask frame 210 to form through-holes 212, only the mask frame formation pattern 244 is formed.

[0118] On the other hand, the lamination and patterning of the etching protection layer 243 shown in Figures 20(b) and (c) are preliminary steps for patterning the base substrate 241 and can be performed after the mask sheet 20 has been formed instead of being carried out in this stage.

[0119] Next, as shown in Figure 20(d), a conductive layer 246 is formed on the insulating film 242. In this embodiment, an example is shown in which an adhesive layer 245 is additionally laminated to strengthen the adhesion to the conductive layer 246 before forming the conductive layer 246. In this case, the adhesive layer 245 and the conductive layer 246 may be laminated in that order.

[0120] A conductive metal such as copper (Cu) may be used as the conductive layer 246, and a metallic material containing titanium may be used as the adhesive layer 245. The conductive layer 246 and the adhesive layer 245 can be formed by a vapor deposition method such as sputtering.

[0121] Alternatively, instead of using the adhesive layer 245, a conductive metal doped with impurities can be used as the conductive layer 246. For example, magnesium-doped copper can be used to form the conductive layer 246, thereby strengthening the bonding force between the conductive layer 246 and the base substrate 241.

[0122] Next, as shown in Figure 20(e), a photoresist 247 is laminated onto the conductive layer 246, and the photoresist 247 is patterned in a form corresponding to the mask pattern 222, window holes 231, and keyholes 232 (S22). Specifically, a photomask with pattern holes corresponding to the mask pattern 222 and alignment marks 230 is placed on top of the photoresist 247 film, and the exposure and development process is carried out to perform the patterning. For reference, Figure 20(e) shows the form of the photoresist 247 after the patterning is completed through such a process, which may include a portion 247a for mask pattern formation and a portion 247b for alignment mark formation.

[0123] Next, as shown in Figure 20(f), electroforming is performed on the areas other than the patterned photoresist 247 to form a mask sheet 220 (S23). Electroforming is performed in a plating tank filled with a plating solution. By connecting a negative electrode terminal to the conductive layer 246 and a positive electrode terminal to the positive electrode body on the opposite side and supplying power, the conductive layer 246 will be plated. Plating solutions containing nickel (Ni) ions and iron (Fe) ions, or nickel (Ni) ions, iron (Fe) ions, and cobalt (Co) ions can be used as the plating solution.

[0124] Then, as shown in Figure 20(g), when the photoresist 247 is removed from the conductive layer 246, the removed portion forms the mask pattern 222 and alignment marks 230. The photoresist 247 can be removed through a wet process.

[0125] Next, as shown in Figure 21, the base substrate 241 and conductive layer 246 are patterned to expose the mask pattern 222 and alignment marks 230, thereby forming the mask frame 210 (S24).

[0126] Specifically, as shown in Figure 21(a), the base substrate 241 is etched through the mask frame formation pattern 244 and the through-hole formation pattern 249 of the etching protection layer 243. At this time, wet etching using an etching solution may be used to etch the base substrate 241. Through this etching process, a central hole 224 is formed in the center of the base substrate 241, and through-holes 212 are formed at the edges. At this time, the insulating film 242 is used as a barrier that prevents the layer located above it from being arbitrarily etched, i.e., an etching stopping layer. Accordingly, it becomes possible to prevent the mask sheet 220 from being damaged by the etching solution.

[0127] Next, as shown in Figure 21(b), the insulating film 242 is patterned through a mask frame formation pattern 244 and a through-hole formation pattern 249 of the etching protective layer 243, which can be carried out by wet etching using an etching solution that selectively etches the insulating film 242.

[0128] Next, as shown in Figure 21(c), the adhesive layer 245 is patterned through the mask frame formation pattern 244 and the through-hole formation pattern 249 of the etching protective layer 243. This can be done by wet etching using an etching solution that selectively etches the adhesive layer 245.

[0129] Next, as shown in Figure 21(d), the conductive layer 246 is patterned through the mask frame formation pattern 244 and the through-hole formation pattern 249 of the etching protective layer 243. This can also be carried out by wet etching using an etching solution that selectively etches the conductive layer 246, thereby completing the formation of the mask frame 210 and completing the fabrication of the shadow mask 1.

[0130] In this embodiment, the base substrate 241, insulating film 242, adhesive layer 245, conductive layer 246, etc., were patterned using the etching protective layer 243. However, other patterning methods using photoresist may also be used.

[0131] Furthermore, patterning may also be possible through dry etching in addition to the wet etching exemplified in this embodiment.

[0132] Although the above has been described with reference to specific embodiments of the present invention, a person with ordinary skill in the relevant art will understand that the present invention can be modified and altered in various ways without departing from the spirit and scope of the invention as described in the following claims. [Explanation of Symbols]

[0133] 1. 100 Shadow Mask 2 circuit boards 3. Alignment Keys 4 Pattern Keys 5. Auxiliary alignment keys 10,210 Mask Frames 20,220 Mask Sheets 22,222 demonstrator patterns 25 Etching area 31,241 base board 33, 243 Etching protection layer 35, 245 Adhesive Layer 37, 244 Patterns for forming mask frames 39, 242 insulating film 40,246 conductive layers 42,247 Photoresist L laser light P welding point H fever 212 Through Hole 223 Fine Pattern Holes 222 Mask Patterns 223 Fine Pattern Holes 224 Central Hall 230 Alignment Marks 231 Window Hole 232 Keyhole 234 Pattern Holes 236 Auxiliary keyhole 249 Through-hole forming pattern

Claims

1. The steps include forming a conductive layer on the base substrate, The steps include: stacking a photoresist on the conductive layer and patterning it in a form corresponding to the mask pattern; The steps include: performing electroforming on areas other than the patterned photoresist to form a mask sheet; The steps include: forming a mask frame by patterning the base substrate and conductive layer so that the mask pattern is exposed; A method for manufacturing a shadow mask, comprising the step of performing a phototreatment or heat treatment to strengthen the bonding force between the mask sheet and the conductive layer before or after forming the mask frame or during the process of forming the mask frame.

2. The method for manufacturing a shadow mask according to claim 1, characterized in that the aforementioned phototreatment includes laser welding using laser light.

3. The method for manufacturing a shadow mask according to claim 2, characterized in that the laser welding is performed on the outer region of the mask pattern provided in multiple locations on the mask sheet.

4. The method for manufacturing a shadow mask according to claim 3, characterized in that the welding points of the laser welding are set in multiple locations so as to be separated by a certain distance along the outer edge of the mask pattern.

5. The method for manufacturing a shadow mask according to claim 2, characterized in that the laser welding is performed such that the mask frame and the mask sheet are welded together.

6. The method for manufacturing a shadow mask according to claim 5, characterized in that the welding points for the laser welding are set in multiple locations so as to be separated by a certain distance along the outer and inner circumferences of the mask frame.

7. When forming the mask frame, support ribs are formed together between the multiple mask patterns. The method for manufacturing a shadow mask according to claim 5, characterized in that the laser welding is performed such that the support rib and the mask sheet are welded together.

8. The method for manufacturing a shadow mask according to claim 1, characterized in that the heat treatment includes a heating step performed in a heating furnace or a resistance welding step of applying current and pressure to the joint.

9. The method for manufacturing a shadow mask according to claim 8, characterized in that the heat treatment is performed after the photoresist is removed from the mask sheet.

10. A method for manufacturing a shadow mask according to claim 1, further comprising the step of forming an adhesive layer to strengthen the adhesion between the base substrate and the conductive layer before forming the conductive layer.

11. The method for manufacturing a shadow mask according to claim 1, characterized in that the conductive layer is formed of a conductive metal doped with impurities so as to enhance the adhesive force between the base substrate and the conductive layer.

12. The method for manufacturing a shadow mask according to claim 1, further comprising the step of forming an insulating film used as an etching stop layer during patterning of the base substrate before forming the conductive layer.

13. It's a shadow mask, Mask frame and A mask sheet made of Invar material supported by the aforementioned mask frame, A mask pattern formed on the mask sheet for selectively passing the deposition material during the deposition process, The mask sheet includes alignment marks formed on its outer region for alignment with the substrate to be deposited, The aforementioned alignment marks are A window hole is formed through the mask sheet to allow light emitted from the light source of the alignment device to pass through, and to acquire an image of the alignment key on the substrate. A shadow mask characterized by including a keyhole formed through at least one side of the window hole for relative alignment with the alignment key.

14. The aforementioned window hole has a polygonal shape, The shadow mask according to claim 13, characterized in that the keyhole is formed on at least one side of each side of the polygon.

15. The alignment key has a configuration in which multiple pattern keys are arranged at regular intervals. The shadow mask according to claim 13, characterized in that the keyhole includes a plurality of pattern holes formed to correspond to the shape and position of the pattern key.

16. The shadow mask according to claim 13, characterized in that the mask frame has through holes formed at positions corresponding to the alignment marks.

17. The aforementioned substrate has additional auxiliary alignment keys formed on it. The shadow mask according to claim 13, characterized in that the alignment marks further include auxiliary keyholes formed at positions corresponding to the auxiliary alignment keys.

18. In the method for manufacturing a shadow mask according to claim 13, The steps include forming a conductive layer on the base substrate, The steps include: laminating a photoresist onto the conductive layer and patterning it in a form corresponding to the mask pattern, the window hole, and the keyhole; The steps include: performing electroforming on areas other than the patterned photoresist to form a mask sheet; A method for manufacturing a shadow mask, comprising the steps of: patterning the base substrate and conductive layer to form a mask frame such that the mask pattern, the window hole and the keyhole are exposed.

19. The method for manufacturing a shadow mask according to claim 18, characterized in that, when patterning the base substrate for exposure of the mask pattern, the window hole and the through hole for exposure of the keyhole are both patterned.

20. The method for manufacturing a shadow mask according to claim 18, further comprising the step of forming an insulating film used as an etching stop layer during patterning of the base substrate before forming the conductive layer.

Images