KR20030093959A - Mask frame assembly for thin layer vacuum evaporation of organic electro luminescence device - Google Patents

Abstract

PURPOSE: A mask frame assembly for depositing a thin film of an organic electro-luminescence display is provided to enhance the accuracy of a total pitch of a masking pattern portion by dividing a mask into unit mask members. CONSTITUTION: A mask frame assembly for depositing a thin film of an organic electro-luminescence display includes a frame(30) and a mask(100). An opening portion is formed on the frame(30). The mask(100) is formed with two unit mask members(110,110'). Both ends of the unit mask members(110,110') are fixed to apply the tensile force to the frame(30). The unit mask members(110,110') have unit masking pattern portions. An inlet portion is formed on an overlapped portion between the unit mask members(110,110'). The thickness of the overlapped portion is equal to the thickness of the unit mask member.

Description

Mask frame assembly for thin film vacuum evaporation of organic electroluminescence device

The present invention relates to a metal mask, and more particularly to a single film deposition mask frame assembly for depositing a thin film forming an organic electroluminescent device.

Organic electroluminescent devices are attracting attention as next generation display devices because of their advantages such as wide viewing angle, excellent contrast and fast response speed as active light emitting display devices.

The organic electroluminescent device is classified into an inorganic electroluminescent device and an organic electroluminescent device according to a material forming the light emitting layer. The organic electroluminescent device has excellent characteristics such as brightness, response speed, and the like in comparison with the inorganic electroluminescent device. Has the advantage of being possible.

The organic electroluminescent device includes a first electrode formed in a predetermined pattern on a transparent insulating substrate, an organic light emitting layer formed by vacuum deposition on the insulating substrate on which the first electrode is formed, and formed on an upper surface of the organic light emitting layer. And second electrodes serving as cathode electrodes in a direction intersecting with each other.

In fabricating the organic electroluminescent device configured as described above, the first electrode is made of indium tin oxide (ITO), and the patterning of the ITO is wet etching in an etchant containing ferric chloride using photolithography. Patterned by law. However, when the second electrode, which is the cathode electrode, is also etched by using the photolithography method, organic electrons are formed because moisture penetrates into the interface between the organic light emitting layer and the second electrode in the process of peeling the resist and in the process of etching the second electrode. It causes a problem of significantly deteriorating the performance and lifespan characteristics of the light emitting device.

In order to solve this problem, a manufacturing method for depositing an organic electroluminescent material constituting the organic light emitting layer and a material constituting the second electrode has been proposed.

In order to fabricate an organic electroluminescent device using such a deposition method, a first electrode made of ITO or the like is formed on a transparent insulating substrate by photolithography or the like to form a stripe shape. The organic light emitting layer is formed by laminating an organic light emitting layer on a transparent substrate on which the first electrode is formed, and then a mask having the same pattern as that of the second electrode is adhered to the organic light emitting layer, and a second electrode forming material is deposited to form a second electrode.

A mask for depositing a second electrode, which is an organic light emitting layer or a cathode, an organic electroluminescent device using the mask, and a method of manufacturing the same are disclosed in Korean Unexamined Patent Publication No. 2000-060589.

The mask for deposition disclosed herein has a structure in which slots on the stripe are formed spaced apart from each other at predetermined intervals in the body of the thin plate.

The mask disclosed in Korean Unexamined Patent Publication No. 1998-0071583 forms a mesh shape of a slit portion and a bridge portion on a metal sheet.

The mask disclosed in Unexamined-Japanese-Patent No. 2000-12238 has an electrode mask part and a pair of terminal mask part. The electrode mask portion has a width corresponding to a gap between the cathode electrode, that is, the second electrode, and has a connecting portion connecting the both ends of the marking portion on the stripe and the plurality of marking portions installed in parallel with each other.

As described above, the masks of the related art are formed with a stripe-shaped hole in the thin metal sheet, so that even if the tension is applied to the frame supporting the edge of the thin metal sheet, the mask is sag due to the weight of the mask and is not adhered to the substrate. There is a problem. This problem is exacerbated as the substrate becomes larger. In addition, as the mask is inflated by the heat applied to the mask during the cathode deposition process, the deflection due to the weight of the strips forming the slots is increased.

An example of a mask for mass production is shown in FIG. 1.

As shown, the unit masking pattern portions 12 are provided to deposit a plurality of unit substrates constituting the organic electroluminescent device on one metal thin plate 11, and the mask is applied to the frame 20 so as to apply a tensile force to the frame 20. It is fixed.

Since the conventional mask 10 is relatively large for mass production, even if a tensile force is uniformly applied when it is fixed to the grid-shaped frame 20, the problem caused by the above-mentioned weight is exacerbated. In particular, the large-area thin metal mask should be welded to the frame 20 to maintain the width of the slot 12a formed in each unit masking pattern portion 12 within a set tolerance range. In this case, when a tensile force is applied in each direction to prevent the deflection of the mask, distortion is generated in the pitch of the slots 12a of the masking pattern portions 12, and thus it is impossible to set the tolerance within the set tolerance range. In particular, when the slot of the unit masking pattern portion 12 of a specific portion of the mask 10 is deformed, a force is applied to all of the neighboring slots so that the slot is moved relative to the substrate to be deposited so that it is out of the tolerance range of the set pattern. do. This phenomenon becomes a problem in the normal direction (the direction orthogonal to the longitudinal direction of the slot) of the slot 12a formed in the mask.

In particular, when the unit masking pattern part 12 is distorted, a cumulative value due to a shift between absolute unit positions formed between the unit electrode patterns formed on the substrate for thin film deposition and each unit masking pattern part 12 (hereinafter, referred to as a total pitch). It is difficult to form accurate red, blue, and green organic films on the unit electrode patterns of the substrate. On the other hand, since the pitch adjustment and the total pitch of the unit masking pattern portion 12 formed in the enlarged metal thin plate is possible only in a very limited portion, there is a limit to the enlargement of the mask 10.

As shown in FIG. 2, when the single disc mask 10 is fixed to the frame 20, the frame 20 is applied by applying a tensile force at each side of the single disc mask as described above by the tensile force applied to the mask 10. ), The support bars 21 on both sides of the frame 20 are bent inward by the tension of the mask 10, and the upper and lower support bars 22 forming the upper and lower parts of the frame are convexly curved in the vertical direction. Thus, deformation occurs or as shown in FIG. 3, the support bars 21 on both sides are convexly curved outwardly, and the upper and lower support bars 22 forming the upper and lower parts of the frame are curved inwardly.

This makes it even more difficult to adjust the total pitch against deformation of the unit mask and misalignment between the unit electrode patterns formed on the substrate even when the mask 10 is uniformly applied with the tensile force and welded to the frame 20.

A mask for solving the problem of creep deformation of strips forming slots due to thermal expansion of the mask is disclosed in Japanese Laid-Open Patent Publication No. 2001-247961.

The disclosed mask is a deposition mask for use in forming a patterning film by vapor deposition on a substrate, the mask portion having a partition wall partitioning a plurality of first openings, and each opening area is larger than the opening area of each of the first openings. A plurality of second openings are provided, and the plurality of second openings includes a screen portion including magnetic material disposed on each of the first openings of the mask portion.

In addition, Japanese Patent Laid-Open Publication No. 2001-273979 discloses a structure of a magnetic mask, and Japanese Laid-Open Patent Publication No. 2001-254169 uses a mask pattern corresponding to a deposition region by masking a deposition portion in close contact with a deposition target. The mask frame has a mask pattern including a minute gap and a fine pattern portion that are difficult to support a predetermined dimension compared to the frame thickness, and has a structure in which the fine pattern portion of the mask pattern is supported by the fine ribs.

As described above, the mask supported on the frame is made of magnetic material to be in close contact with the deposit, but the pitch between the strips is changed according to the self weight of the mask and the tension of the mask. Fundamental problems such as total pitch change cannot be solved.

In addition, Japanese Patent Application Publication No. 2002-235165 and US Patent No. US 3,241,519 for preventing thermal deformation of pattern openings and improving precision are provided. A plurality of unit patterns are provided in a single frame and mask for a pattern of a large display. The formed mask is disclosed in European Patent Publication EP 1,209,522 A2 and similar masks are disclosed in US Patent Publication US 2002/0025406 A1. However, these masks also suffer from the problems described above.

In addition, European Patent Publication No. EP 1,229,144 A2 discloses a mask frame assembly for supporting a plurality of masks by a single frame having an opening corresponding to each mask, but there is a limit to narrowing the intervals between the masks. Therefore, waste of the substrate to be deposited is severe, assembly of the mask is also complicated, and there is a limit that cannot be used for pattern formation of a large display.

On the other hand, in order to solve the problems described above, the applicant has applied for a mask frame assembly in the Korean Patent Application No. 2001-76490.

The mask includes at least two unit masks in which at least one unit masking pattern part is formed in a length direction. Since such a mask has a unit masking pattern portion formed in the unit mask, it is not easy to apply the mask as described above in the case of having a large single mask pattern portion. In addition, deposition of an organic film into a gap between the unit masks is caused, resulting in loss of organic matter.

In order to solve the above problems, the present invention can reduce the distortion of the deposition pattern according to the enlargement of the masking pattern portion, and provides a mask frame assembly for thin film deposition of an organic electroluminescent device that is easy to adjust the total pitch between the deposition patterns. Has its purpose.

Another object of the present invention is to prevent the deposition of aluminum forming an organic material or an electrode in an undesired position by a gap between the unit mask members, which enables a single, large masking pattern, and to prevent external forces or internal stresses of the mask and the frame. The present invention provides a mask frame assembly for thin film deposition of an organic electroluminescent device capable of minimizing additional total pitch variation.

Another object of the present invention is to provide a mask frame assembly for thin film deposition of an organic electroluminescent device capable of reducing a howling phenomenon caused by an external impact of a single large masking pattern portion.

1 is an exploded perspective view of a mask frame assembly for thin film deposition of a conventional organic electroluminescent device;

2 and 3 are a plan view of a conventional mask frame assembly,

4 is an exploded perspective view illustrating a mask frame assembly for depositing a thin film of an organic light emitting diode according to an exemplary embodiment of the present invention;

5 is a partial ablation perspective view showing an extract of the inlet of the unit mask member;

6 and 7 are a perspective view showing another embodiment of the inlet;

8 is a partially broken perspective view of a portion of the mask frame assembly according to FIG. 4, FIG.

9 is an exploded perspective view illustrating a mask frame assembly for depositing a thin film of an organic electroluminescent device according to another exemplary embodiment of the present invention;

10 is an exploded perspective view illustrating a mask frame assembly for thin film deposition of an organic electroluminescent device according to another exemplary embodiment of the present invention;

FIG. 11 is a partially broken perspective view showing the bottom of the mask frame assembly according to FIG. 10; FIG.

12 is a bottom view of the mask frame assembly according to FIG. 10, FIG.

13 is a side cross-sectional view of the mask frame assembly according to FIG. 10;

14 is an exploded perspective view illustrating a mask frame assembly for thin film deposition of an organic light emitting diode according to another embodiment of the present invention;

15 is a schematic cross-sectional view of a vapor deposition apparatus for depositing an organic film on a substrate.

In order to achieve the above object, the present invention provides a frame having an opening and at least two unit mask members fixed at both ends to apply a tensile force to the frame, each having a unit masking pattern portion, and overlapping each other with a predetermined width. Wherein the at least overlapping portions of the unit mask members include masks each having an inlet formed such that the thickness of the overlapping portion is substantially the same as that of the unit mask member. Provide a wear mask frame assembly.

According to another feature of the invention, the inlet portion of the unit mask member has a predetermined width may be made by half etching in the longitudinal direction.

In this case, the inlet of the unit mask member may be formed to be inclined or stepped.

According to another feature of the invention, the width of the inlet portion may be formed substantially the same or wider than the thickness of the unit mask member.

According to another feature of the invention, the width of the inlet portion may be formed to 30 to 100㎛.

According to another feature of the invention, the width of the overlapping portions of the unit mask members may be 10㎛ to 70㎛.

According to another feature of the present invention, the mask may be provided to form a single masking pattern portion by each unit masking pattern portion of the unit mask members, or may be provided to form an independent masking pattern portion of each unit masking pattern portion, respectively. .

In order to achieve the above object, the present invention also provides a frame having an opening and at least two unit mask members fixed at both ends to apply a tensile force to the frame, each having a unit masking pattern portion and spaced apart from each other by a predetermined interval. It provides a mask frame assembly for thin film deposition of an organic electroluminescent device, characterized in that it comprises a mask formed so that spaced gaps between the unit mask members are shielded by a separate sheet member.

According to this other feature of the present invention, both ends of the sheet member may be bonded to the frame.

According to another feature of the present invention, the width of the sheet member may be greater than or equal to a gap between the unit mask members and a distance between adjacent unit masking pattern portions of adjacent unit mask members.

According to another feature of the present invention, the mask may be provided to form a single masking pattern portion by each unit masking pattern portion of the unit mask members, or each unit masking pattern portion may be provided to form an independent masking pattern portion. .

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

4 shows an embodiment of a mask frame assembly for thin film deposition of an organic electroluminescent device according to a preferred embodiment of the present invention.

Referring to the drawings, the mask frame assembly according to an embodiment of the present invention overlaps the frame 30 and the unit mask members 110 and 110 ′ whose both ends are supported to apply a tensile force to the frame 30. The mask 100 is installed so as to be roughly divided.

The frame 30 may include a first support part 31 and 32 installed in parallel with each other, and a second support part connected to ends of the first support parts 31 and 32 to form a lattice opening 33. 34) 35. The second support parts 34 and 35 may be formed in a direction parallel to the unit mask members 110 and 110 ′, but may be formed of a material having elastic force, but the present invention is not limited thereto. 31 and 32 and the second support part 34 and 35 may be integrally formed.

The frame 30 should have a rigidity that can sufficiently provide the tensile force applied to the unit mask members 110 and 110 ′ which will be described later, and may be any structure as long as it does not cause interference between the deposition material and the mask.

The mask 100 has a plurality of unit mask members 110 and 110 ′ which are supported at both ends thereof to apply a tensile force to the frame 30, and each having unit masking pattern portions 150 and 150 ′. According to an exemplary embodiment of the present invention, the unit mask members 110 and 110 ′ may overlap one another to form one masking pattern part 200 larger than an area of the unit mask member. .

4 and 5, the unit mask members 110 and 110 ′ are made of a thin plate on a slip, and unit masking pattern parts 150 and 150 ′ are formed at predetermined intervals along a length direction thereof. Is formed. The unit mask members 110 and 110 ′ are not limited to strips.

As shown in FIG. 5, the unit masking pattern parts 150 and 150 ′ are formed by dots or slits 120 and 120 ′ formed on a thin plate forming the unit mask members 110 and 110 ′. The masking pattern parts 150 and 150 ′ are not limited to the above-described embodiments, and may be modified in various forms according to a pattern to be deposited.

In addition, the thicknesses of the overlapping portions of the unit mask members 110 and 110 ′ may be substantially equal to the thicknesses of the unit mask members 110 and 110 ′, respectively. 130 'is formed. The inlet portions 130 and 130 'of the unit mask members 110 and 110' are formed to be inclined in a wave shape having a compound curvature as shown in FIG. 5 or to be inclined as shown in FIG. 6. Can be. As illustrated in FIG. 7, the inlets 130 and 130 ′ may be formed to have curved surfaces symmetrical to each other.

The lead portions 130 and 130 ′ of the unit mask members 110 and 110 ′ may be etched to about half the thickness of the unit mask members 110 and 110 ′ by half etching. In addition, the inlet portions 130 and 130 'may be formed such that the shapes of the inlet portions 130 and 130' of the unit mask members 110 and 110 'adjacent to each other are symmetrical to each other. Thus, when they are overlapped, as shown in FIGS. 5 to 7, the overlapped overlapping portion may be substantially the same as the thickness of the unit mask members 110 and 110 ′.

Meanwhile, the width W1 of the lead portions 130 and 130 'of the unit mask members 110 and 110' is preferably 30 to 100 μm, but is not limited thereto. The width W1 of the inlet portions 130 and 130 'may correspond to patterns and slots of the slots 120 and 120' of the masking pattern portions 150 and 150 'of the inlet portions 130 and 130'. It can be adjusted in consideration of the pitch between (120) and (120 '), preferably formed in 50㎛. The width W2 of the overlapping portions of the adjacent unit mask members 110 and 110 ′ is preferably 10 μm to 70 μm. The width W2 of the overlapped portion may be appropriately adjusted in consideration of the thermal expansion of the unit mask members 110 and 110 ′ and the tensile force and total pitch applied to the unit mask members 110 and 110 ′. Of course.

Meanwhile, the unit mask members 110 and 110 ′ are fixed to the first support members 31 and 32 of the frame, respectively, while the unit mask members 110 and 110 ′ have a tensile force applied thereto. The fixing of the 110 'to the frame may be performed by spot welding or seam welding, yag laser welding, or the like, but is not limited thereto. The edge of the unit mask member 110 ′ positioned outside the mask may be welded along the second support part 35 or 34, as shown in FIG. 8.

As such, according to the present invention, the mask 100 is formed by the unit mask members 110 and 110 ′ having the unit masking pattern portions 150 and 150 ′, respectively. Deformation and distortion of the pattern can be prevented. That is, since each unit mask member 110, 110 'is fixed to the frame 30 in the state in which the tensile force is applied in the Y direction as shown in FIG. 4, a uniform tensile force is applied to each part relatively. It is possible to prevent the concentration of strain on the site.

In addition, according to an exemplary embodiment of the present invention as described above, the unit mask members 110 and 110 ′ overlap each other, such that deposition is not performed between the unit mask members 110 and 110 ′. As a result, each of the unit masking pattern units 150 and 150 ′ may form one large masking pattern unit 200, thereby enabling deposition of a large-area display.

As described above, since the inlet portions 130 and 130 'are formed in the overlapping portions of the unit mask members, the overlapping portions can be prevented from being thickened. It is possible to prevent the single masking pattern portion 200 from being distorted, in particular, the width W1 of the lead portions 130 and 130 ′ is formed to be 50 μm, and the overlapping width W2 is 30 μm. In this case, since it is within the pitch range of the organic film pattern of the organic EL device, it is possible to form a single masking pattern portion 200 sufficiently.

In addition, in the case of a single large mask, the total pitch of the slots of the internal masking pattern portion may be adjusted by a tensile force applied from the edge of the large mask, but the mask 100 of the present invention may include a plurality of unit mask members 110. It is composed of (110 ') so adjustment of the total pitch is acceptable. In particular, since unit masks can be installed independently of a frame, the total pitch can be adjusted for each unit mask.

As described above, the case in which the unit masking pattern portions of the unit mask members form a single masking pattern portion has been described, but the present invention is not limited thereto, and as shown in FIG. 9, each unit mask member 110 ( 110 ') has individual unit masking pattern portions 150 and 150', and the unit masking pattern portions 150 and 150 'are each so as to be independent masking pattern portions for patterning separate organic electroluminescent elements. Of course you can.

Next, FIG. 10 shows a mask frame assembly for thin film deposition of an organic electroluminescent device according to another exemplary embodiment of the present invention. The following description will focus on differences that are distinguished from the above-described embodiments.

As shown in FIG. 10, in the mask frame assembly for thin film deposition of an organic electroluminescent device according to another exemplary embodiment of the present invention, the unit mask members 110 and 110 ′ of the unit mask members 110 and 110 ′ are different from each other. They do not overlap, and are fixed to the frame 30 at a predetermined interval apart. Accordingly, as shown in FIG. 11, the gaps 111 spaced apart from each other exist between the unit mask members 110 and 110 ′. According to another preferred embodiment of the present invention, the gap 111 is shielded by a separate sheet member 160.

The sheet member 160 may be formed of the same material as the unit mask members 110 and 110 ′, and the width of the sheet member 160 may be greater than or equal to the gap 111 so as to be sufficient to shield the gap 111. As shown in FIG. 12, the distance between adjacent unit masking patterns 150 and 150 ′ of adjacent unit mask members 110 and 110 ′ is less than or equal to each unit masking pattern. It is preferable that it is less than or equal to the pattern pitch interval of the parts 150 and 150 '. This is for the sheet member 160 to shield the gap 111, so as not to cover the slit of each pattern portion.

As shown in FIGS. 11 and 13, both of the sheet members 160 are bonded to and fixed to the frame, and the sheet members 160 are bonded to be parallel to the unit mask members 110 and 110 ′. As can be seen, the end of the sheet member 160 to the first support portion 31, 32 to which the unit mask members 110, 110 'are joined can be welded by yag laser welding or the like. have.

Thus, since the sheet member 160 is bonded only to the frame, the sheet member 160 does not have any influence on the pattern precision of the unit mask members. In addition, as the sheet member 160 shields the gap 111 between the unit mask members 110 and 110 ′, deposition is prevented from occurring at an unnecessary location, and as shown in FIG. It is possible to form a large masking pattern portion 200.

Of course, as shown in FIG. 14, the unit mask members 110 and 110 ′ may respectively form independent masking patterns.

The thin film deposition mask frame assembly of the organic electroluminescent device according to the present invention configured as described above is mounted on the deposition apparatus as shown in FIG. 15 to perform deposition.

Referring to the drawings, in order to deposit a thin film of an organic electroluminescent device, that is, a red, green or blue organic film or a cathode layer, etc. using the mask 100, an organic film deposition container installed inside the vacuum chamber 201. The mask frame assembly is installed on the side corresponding to the crucible 202 and the substrate 300 on which the thin film is to be formed is mounted. In addition, the magnet unit 400 for driving the mask 100 supported on the frame 30 to the substrate 300 may be driven to the mask 100 to closely adhere to the substrate 300.

In this state, the organic material or the cathode forming material attached thereto is evaporated and deposited on the substrate 300 by the operation of the organic film deposition container 202. In this process, the mask 100 undergoes sag and slight thermal expansion due to its own weight. The mask 100 is composed of a single mask member 100 (110 '), as described above. Severe deformation and distortion of a single pattern can be prevented. That is, the unit mask 110 is fixed to the frame 30 in a state in which the tensile force is applied in the Y direction on the strip, as shown in FIGS. Uniform tensile force is applied, and it is possible to prevent the concentration of deformation on a specific site.

As described above, the unit mask members fixed to the frame may be prevented from being deposited at an undesired position by allowing the inlet portions to overlap with each other or the gaps being shielded by the sheet members as described above. As a result, an enlarged single masking pattern can be formed.

In addition, since the total pitch is adjusted using a unit mask member having a plurality of unit masking pattern portions, the total pitch can be adjusted for each unit mask, making the adjustment easier. In addition, the means for shielding the gaps between the unit mask members prevents misalignment of the unit mask members or misalignment of the slits of the mask, thereby further improving the pattern precision.

In the mask frame assembly for forming a thin film of the organic electroluminescent device according to the present invention having the above-described configuration, by dividing the mask provided in the frame into a unit mask member, it is possible to improve the total pitch precision and the pattern precision of the masking pattern portion. The distortion of the pattern due to heat deformation and the like can be reduced.

In addition, by overlapping the unit mask members or shielding the gap with a separate sheet member, it is possible to prevent deposition in an undesired position and to form a single masking pattern portion. Deposition is possible.

It is possible to make the thickness constant by forming the lead portions in the mutually overlapping portions of the unit mask members so that a large single masking pattern portion can be formed without distortion of the unit masking pattern portion.

In the present specification, the present invention has been described with reference to limited embodiments, but various embodiments are possible within the scope of the present invention. In addition, although not described, equivalent means will also be referred to as incorporated in the present invention. Therefore, the true scope of the present invention will be defined by the claims below.

Claims (13)

A frame having an opening; And It is provided with at least two unit mask members fixed at both ends to apply a tensile force to the frame, each having a unit masking pattern portion and overlapping each other with a predetermined width, and overlapping at least overlapping portions of the unit mask members. A mask frame assembly for thin film deposition of an organic electroluminescent device, comprising: a mask having an inlet portion formed such that the thickness of the portion is substantially the same as that of the unit mask member. The method of claim 1, And a lead portion of the unit mask member has a predetermined width and is half etched in a length direction. The method according to claim 1 or 2, And a lead portion of the unit mask member is formed to be inclined or stepped. The method of claim 1, And a width of the lead portion is substantially equal to or wider than a thickness of the unit mask member. The method of claim 4, wherein A mask frame assembly for thin film deposition of an organic light emitting display device, characterized in that the width of the inlet is formed in 30 to 100㎛. The method of claim 4, wherein A mask frame assembly for thin film deposition of an organic light emitting display device, wherein the widths of the overlapping portions of the unit mask members are 10 μm to 70 μm. The method of claim 1, And the mask is formed to form a single masking pattern portion by each unit masking pattern portion of the unit mask members. The method of claim 1, The mask is a mask frame assembly for thin film deposition of an organic light emitting display device, characterized in that each of the unit masking pattern portion of the unit mask member is formed to form an independent masking pattern portion. A frame having an opening; And Both ends are fixed to the tensile force applied to the frame, each having a unit masking pattern portion, provided with at least two unit mask members spaced apart from each other by a predetermined interval, the spaced gap between the unit mask members is a separate sheet member And a mask formed to be shielded by the mask frame assembly for thin film deposition of an organic electroluminescent device. The method of claim 9, The sheet member is a mask frame assembly for thin film deposition of an organic electroluminescent device, characterized in that both ends are fixed to the frame. The method of claim 9, The sheet member has a width greater than or equal to a gap between the unit mask members and a distance between adjacent unit masking pattern portions of adjacent unit mask members. The method according to any one of claims 9 to 11, And the mask is formed to form a single masking pattern portion by each unit masking pattern portion of the unit mask members. The method according to any one of claims 9 to 11, The mask is a mask frame assembly for thin film deposition of an organic light emitting display device, characterized in that each of the unit masking pattern portion of the unit mask member is formed to form an independent masking pattern portion.