JP7203887B2 - Mask and manufacturing method thereof - Google Patents

Description

The present invention relates to a mask and its manufacturing method.

Patent Document 1 discloses a vapor deposition mask in which a frame 103 for reinforcing the mask body 102 is attached to the outer peripheral edge of the mask body 102, as shown in FIG. The frame 103 there is made of a material having a coefficient of linear thermal expansion equivalent to that of the vapor-deposited substrate 30 or a material having a low coefficient of thermal expansion. The frame 103 is fixed on the mask main body 102 via an adhesive 108 that is stable against temperature changes, such as a heat-resistant ceramic adhesive or a heat-resistant epoxy resin adhesive. The mask main body 102 is provided with a vapor deposition pattern 106 for forming the light emitting layer 310 of the organic EL element, which consists of a large number of independent vapor deposition through-holes 105 , in the pattern forming region 104 . According to the vapor deposition mask disclosed in Patent Document 1, even if the coefficient of linear thermal expansion of the material forming the mask body 102 is different from that of the substrate 30 to be vapor-deposited, the mask body 102 has the same coefficient of linear thermal expansion as the substrate 30 to be vapor-deposited. The shape changes with the expansion of the frame 103, or the shape does not change because it is suppressed by the frame 103 having a low coefficient of linear thermal expansion. Since the temperature can be maintained satisfactorily even when the temperature is raised in the kiln, there is an advantage that the light-emitting layer 310 can be formed on the substrate 30 to be vapor-deposited with high accuracy and good reproducibility. In addition, there is a mask structure having a first metal layer and a second metal layer.

Japanese Patent Application Laid-Open No. 2002-371349

The vapor deposition mask method is a method in which a vapor deposition mask is placed on a substrate to be vapor-deposited, and an organic material vaporized by a vaporization source is vapor-deposited in vapor deposition holes of the vapor deposition mask to form a light-emitting layer on the substrate to be vapor-deposited. Therefore, the light-emitting layer formed on the substrate to be vapor-deposited is required to have a uniform height dimension. However, if the vapor deposition through hole 105 of the vapor deposition mask has a straight shape as in the vapor deposition mask shown in FIG. The organic material entering the vapor deposition hole 105 from any direction is blocked by the upper edge of the opening of the mask. The layer 310 tends to have a substantially waterdrop-like shape in a cross-sectional view with a swollen center portion and a gradually tapered edge portion. The light-emitting layer 310 having such a distorted shape has uneven brightness, which is a major obstacle to achieving high precision of the device. In addition, in the case of a mask having a first metal layer and a second metal layer, there is a risk of peeling from the interface between the first metal layer and the second metal layer. is not disclosed.

SUMMARY OF THE INVENTION An object of the present invention is to provide a mask that can prevent peeling from the interface between a first metal layer and a second metal layer, and a method of manufacturing the same.

A vapor deposition mask 1 according to the present invention has a mask body 2 provided with a vapor deposition pattern 6 comprising a large number of independent vapor deposition through holes 5 . In the vapor deposition through hole 5, a small hole portion 5a positioned on the vaporization source side and a large hole portion 5b positioned on the vapor deposition target substrate 30 side and formed to be larger than the opening shape of the small hole portion 5a communicate with each other. It is characterized by being

The mask body 2 has first metal layers 13 and 44 and second metal layers 16 and 45, and the second metal layers 16 and 45 cover the top and side surfaces of the first metal layers 13 and 44. The cross-sectional shape of the mask body 2 between the vapor deposition through holes 5 is stepped.

Further, the upper edge portions of the second metal layers 16 and 45 facing the peripheral surfaces of the large hole portion 5b and the small hole portion 5a are rounded.

In addition, the vapor deposition pattern 6 is formed in the pattern formation region 4, the frame 3 made of a material with a low coefficient of linear thermal expansion is arranged around the outer periphery of the mask body 2, and the outer periphery of the pattern formation region 4 of the mask body 2 is arranged. 4a and the frame 3 are integrally joined with a metal layer 9 interposed therebetween.

The present invention also relates to a method of manufacturing a vapor deposition mask in which a mask body 2 is provided with a vapor deposition pattern 6 consisting of a large number of independent vapor deposition through holes 5. 12, forming a first metal layer 13 on a master mold 10 using a primary pattern resist 12, and forming a secondary pattern resist 15 having a resist body 15a on the surface of the master mold 10. forming a second metal layer 16 on the master mold 10 and the first metal layer 13 using the secondary pattern resist 15; and peeling off together.

Further, the present invention is a method for manufacturing a vapor deposition mask in which a mask body 2 is provided with a vapor deposition pattern 6 composed of a large number of independent vapor deposition through holes 5, and the step of preparing a master mold 40 having a metal film 41 patterned thereon. a step of forming a pattern resist 43 having a resist body 43a on the surface of the master mold 40; a step of forming a first metal layer 44 on the metal film 41 using the pattern resist 43; It is characterized by including a step of forming a second metal layer 45 on the first metal layer 44 and a step of peeling off the first metal layer 44 and the second metal layer 45 together from the master mold 10 .

According to the mask of the present invention, peeling from the interface between the first metal layer and the second metal layer can be prevented.

Moreover, according to the mask manufacturing method of the present invention, it is possible to manufacture a mask having good adhesion between the first metal layer and the second metal layer.

BRIEF DESCRIPTION OF THE DRAWINGS The vertical side view of the vapor deposition mask which concerns on 1st Embodiment of this invention. 1 is an exploded perspective view of a vapor deposition mask according to a first embodiment of the present invention; FIG. Process explanatory drawing of the manufacturing process of the vapor deposition mask which concerns on 1st Embodiment of this invention Process explanatory drawing of the manufacturing process of the vapor deposition mask which concerns on 1st Embodiment of this invention Process explanatory drawing of the manufacturing process of the vapor deposition mask which concerns on 1st Embodiment of this invention FIG. 4 is a longitudinal side view of a vapor deposition mask according to a second embodiment of the present invention; The top view of the principal part of the vapor deposition mask which concerns on 2nd Embodiment of this invention. The perspective view of the principal part of the vapor deposition mask which concerns on 2nd Embodiment of this invention. The exploded perspective view of the vapor deposition mask which concerns on 2nd Embodiment of this invention. Process explanatory drawing of the manufacturing process of the vapor deposition mask which concerns on 2nd Embodiment of this invention Process explanatory drawing of the manufacturing process of the vapor deposition mask which concerns on 2nd Embodiment of this invention Process explanatory drawing of the manufacturing process of the vapor deposition mask which concerns on 2nd Embodiment of this invention Process explanatory drawing of the manufacturing process of the vapor deposition mask which concerns on 3rd Embodiment of this invention Process explanatory drawing of the manufacturing process of the vapor deposition mask which concerns on 3rd Embodiment of this invention A longitudinal side view of a vapor deposition mask according to a third embodiment of the present invention. FIG. 10 is a vertical cross-sectional side view of a mask according to a fourth embodiment of the present invention; Longitudinal cross-sectional view showing a conventional vapor deposition mask

(First embodiment)
In FIG. 1, a vapor deposition mask 1 has a mask body 2 provided with a vapor deposition pattern 6 comprising a large number of independent vapor deposition through holes 5 . The mask body 2 is formed by electroforming using nickel, a nickel alloy such as nickel-cobalt, copper, or other electrodeposited metal as a material. In FIG. 2, the mask main body 2 is formed independently of each other in, for example, four squares of 50×50 mm in a square matrix area of 200×200 mm. . A vapor deposition pattern 6 having vapor deposition through holes 5 is formed in the pattern forming region 4 .

The mask body 2 has a first metal layer 13 and a second metal layer 16 . Specifically, a second metal layer 16 is formed to cover the top and side surfaces of the first metal layer 13 . In this embodiment, the upper surface refers to the vaporization source side, and the side surface refers to the surface facing the vapor deposition through hole 5 . By forming the second metal layer 16 so as to cover the surface of the first metal layer 13 in this way, the first metal layer 13 and the second metal layer 16 are simply stacked, and the Since the contact surface area between the layer 13 and the second metal layer 16 is increased, a laminated structure in which the first metal layer 13 and the second metal layer 16 are firmly adhered can be obtained. The thickness of the mask main body 2 is preferably in the range of 10 to 100 μm, and set to 20 μm in this embodiment. Specifically, the thickness t1 of the first metal layer 13 is preferably in the range of 5 to 90 μm, and is set to 16 μm in this embodiment, and the thickness t2 of the second metal layer 16 is preferably 10 μm or less. In the example, it was set to 4 μm. Incidentally, the thinner the thickness t2 of the second metal layer 16 is, the more the shadow caused by the periphery of the upper end of the vapor deposition through-hole 5 can be eliminated.

Each vapor deposition through-hole 5 is formed by connecting a small hole portion 5a and a large hole portion 5b formed to be larger than the opening shape of the small hole portion 5a. It has a rectangular shape with a front-rear length of 150 μm and a left-right width of 50 μm when viewed from above, and the large hole portion 5 b has a square shape with a front-rear length of 300 μm and a left-right width of 150 μm when viewed from above. have. The small hole portion 5a is on the deposition target substrate 30 side, and the large hole portion 5b is on the vaporization source side. These vapor deposition through holes 5 are arranged in parallel in the front-rear and/or left-right direction to form a vapor deposition pattern 6 . As shown in FIG. 1, the mask body 2 (the first metal layer 13 and the second metal layer 16) between the vapor deposition through holes 5 is formed in a stepped shape in a cross-sectional view, so that the vapor deposition through holes 5 are small. It becomes the form comprised by the hole part 5a and the large hole part 5b. The large hole portion 5b makes it possible to receive the organic material from the vaporization source at a wide angle, and it is possible to deal with the organic material incident from an oblique direction. can contribute. Moreover, as shown in FIG. 1, by forming the upper end peripheral edge portions (vaporization source side peripheral edge portions) of the second metal layer 16 facing the peripheral surfaces of the large hole portion 5b and the small hole portion 5a into rounded shapes, It is possible to eliminate shadows caused by the upper edges of the holes 5b and the small holes 5a as much as possible, widen the acceptance angle of the organic material, and obtain a light-emitting layer with a more uniform height dimension. The longitudinal sectional view of FIG. 1 does not show the appearance of the actual vapor deposition pattern 6, but shows it schematically.

A frame 3 for reinforcing the mask body 2 can be attached to the mask body 2. - 特許庁The frame 3 is made of a material having a low coefficient of linear thermal expansion, such as Invar, which is a nickel-iron alloy, or Super Invar, which is a nickel-iron-cobalt alloy. The frame 3 is a molded product that is thicker than the mask main body 2 , and is inseparably and integrally joined to the outer peripheral edge 4 a of the pattern forming region 4 of the mask main body 2 by means of a metal layer 9 . Here, as shown in FIG. 2, four mask bodies 2 are held by one frame 3 . That is, the frame 3 has four openings 3a aligned on its plate surface, and one mask body 2 is attached to each opening 3a. The frame 3 has an opening 3a corresponding to the mask body 2 and is formed in a flat plate shape. The thickness dimension of the frame 3 is, for example, about 100 to 500 μm, and is set to 200 μm in this embodiment.

The reason why the Invar material and the Super Invar material are adopted as the material for forming the frame 3 is that their coefficient of linear expansion is extremely small, 2×10 -6 /°C or less, or less than 1×10 -6 /°C. This is because the dimensional change of the mask main body 2 due to is suppressed satisfactorily. For example, if the mask body 2 is made of nickel as described above, its coefficient of linear expansion is 12.80×10 -6 /° C. 3.20×10 −6 /° C., the linear expansion coefficient of 3.20×10 −6 /°C. It is inevitable that there will be a positional deviation between the vapor deposition position and the vapor deposition position of the vapor deposition material during actual vapor deposition. Therefore, if a material with a small coefficient of linear expansion, such as Invar, is used as the material for forming the frame 3 that holds the mask body 2, dimensional and shape changes caused by the expansion of the mask body 2 when the temperature rises. can be well suppressed, and the matching accuracy at room temperature can be maintained well even when the temperature is raised during vapor deposition.

In FIG. 1, reference numeral 9 denotes a metal layer laminated on the upper surface of the mask body 2 relating to the outer peripheral edge 4a of the pattern formation region. Specifically, the metal layer 9 is formed on the upper surface of the outer peripheral edge 4 a of the pattern formation region 4 , the upper surface of the frame 3 and the side surface facing the pattern formation region 4 , and the gap between the mask body 2 and the frame 3 . Thus, the outer peripheral edge 4a of the pattern forming region 4 and the peripheral edge of the opening of the frame 3 are joined inseparably and integrally. This metal layer 9 is made of nickel, a nickel-cobalt alloy, or the like, and can be formed by a plating method.

3 to 5 show a method for manufacturing a vapor deposition mask according to this embodiment. First, as shown in FIG. 3A, a photoresist layer 11 is formed on the surface of a matrix 10. Then, as shown in FIG. The matrix 10 is made of, for example, a conductive material such as stainless steel or brass steel. The photoresist layer 11 is formed by laminating one or several sheets of a negative type photosensitive dry film resist to a predetermined height and by thermocompression bonding.

Next, on the photoresist layer 11, a pattern film (glass mask) having light-transmitting holes corresponding to the positions of the large holes 5b of the vapor deposition through-holes 5 is brought into close contact, followed by irradiation with ultraviolet light for exposure. By performing development and drying processes and removing the unexposed portions, a straight resist body 12a corresponding to the position of the large hole portion 5b of the vapor deposition through hole 5 is obtained as shown in FIG. 3(b). A primary pattern resist 12 was formed on the master mold 10 .

Next, the mold 10 is placed in an electroforming bath prepared under predetermined conditions, and as shown in FIG. The uncovered surface (exposed area) was electroformed with a nickel-cobalt alloy, preferably in the range of 5 to 90 μm thick, in this embodiment 16 μm thick, to form the first metal layer 13 . After forming the first metal layer 13, the primary pattern resist 12 (resist body 12a) is removed as shown in FIG. 3(d).

Subsequently, as shown in FIG. 4A, a photoresist layer 14 was formed over the entire surface of the matrix 10 including the region where the first metal layer 13 was formed. The photoresist layer 14 is formed by laminating one or several sheets of a negative type photosensitive dry film resist to a predetermined height and by thermocompression bonding.

Next, a pattern film having light-transmitting holes corresponding to the positions of the small holes 5a of the vapor deposition through-holes 5 is brought into close contact with the pattern film. By removing the part, as shown in FIG. 4B, a secondary pattern resist 15 having a straight resist body 15a corresponding to the position of the small hole portion 5a of the vapor deposition through hole 5 was formed on the master mold 10. .

Next, the matrix 10 is placed in an electroforming bath prepared under predetermined conditions, and as shown in FIG. A second metal layer 16 was formed by electroforming a nickel-cobalt alloy on the surface (exposed region) of 13 not covered with the resist body 16a, preferably to a thickness of 10 μm or less, in this embodiment, to a thickness of 4 μm. . At this time, the second metal layer 16 formed in the portion facing the end (top or base) of the first metal layer 13 has an R shape. In addition, the end portion of the second metal layer 16 facing the vapor deposition through-hole 5 is also rounded. As for the curvature of the R (R), a desired R (R) can be obtained by adjusting the thickness of the second metal layer 16 . Then, by removing the secondary pattern resist 15 (resist body 15a), a mask body 2 having a vapor deposition pattern 6 composed of a large number of independent vapor deposition through-holes 5 was obtained as shown in FIG. 4(d).

Subsequently, as shown in FIG. 5(a), a photoresist layer 17 was formed on the entire surface of the matrix 10 including the portions where the first metal layer 13 and the second metal layer 16 (mask body 2) were to be formed. The photoresist layer 17 is formed by laminating one or several sheets of a negative type photosensitive dry film resist in accordance with a predetermined height and by thermocompression bonding. Next, a pattern film having light-transmitting holes corresponding to the pattern forming regions 4 was brought into close contact with the film, and then exposed to ultraviolet light. Thus, after obtaining a photoresist layer 17 in which the portion related to the pattern forming region 4 is exposed (17a) and the other portion is unexposed (17b), a matrix is formed as shown in FIG. 5(b). A frame body 3 was arranged on 10 so as to surround the first metal layer 13 and the second metal layer 16 . Here, the frame 3 was temporarily fixed on the master mold 10 by utilizing the adhesiveness of the unexposed photoresist layer 17b.

Next, as shown in FIG. 5(c), the unexposed photoresist layer 17b exposed on the surface was removed by dissolving to form a tertiary pattern resist 18 having a resist body 18a covering the pattern forming region 4. Next, as shown in FIG. At this time, the unexposed photoresist layer 17b existing on the lower surface of the frame 3 remains on the matrix 10. Next, as shown in FIG.

Next, as shown in FIG. 5(d), the upper surface of the second metal layer 16 exposed on the surface related to the outer peripheral edge 4a of the pattern forming region 4 and the matrix exposed between the frame 3 and the second metal layer 16 are formed. Electrodeposited metal is electroformed on the surface of 10 and the surface of the frame 3 to form a metal layer 9, and the second metal layer 16 including the first metal layer 13 and the frame 3 are formed by the metal layer 9. joined. At this time, the upper surface of the second metal layer 16 exposed on the surface related to the outer peripheral edge 4a of the pattern formation region 4, and the metal layer 9 on the surface of the matrix 10 exposed between the frame 3 and the second metal layer 16 was 30 μm, and the layer thickness of the metal layer 9 on the surface of the frame 3 was 15 μm. The reason why the layer thickness is different between the surface of the matrix 10 and the frame 3 is that the metal layer 9 is sequentially laminated from the surface of the matrix 10, and the metal layer 9 is unexposed. When the height dimension of the photoresist layer 17b is exceeded to reach the frame 3, the frame 3 is electrically connected to the matrix 10, and the metal layer 9 is formed on the surface of the frame 3. As shown in FIG.

Finally, after removing the first metal layer 13, the second metal layer 16, and the metal layer 9 from the master mold 10, the tertiary pattern resist 18 and the unexposed photoresist layer 17b existing on the lower surface of the frame 3 are removed. By doing so, a mask 1 as shown in FIG. 1 was obtained.

(Second embodiment)
A vapor deposition mask according to a second embodiment of the present invention will be described with reference to FIGS. 6 to 12. FIG. In FIG. 6, a vapor deposition mask 1 has a mask body 2 provided with a vapor deposition pattern 6 consisting of a large number of independent vapor deposition through-holes 5. This mask body 2 is made of nickel, a nickel alloy such as nickel cobalt, copper, or other metals. It is formed by electroforming using an electrodeposited metal as a material. In FIG. 9, the vapor deposition mask 1 has a rectangular shape of 500 mm×400 mm, and has a plurality of mask bodies 2 inside. Each mask body 2 is formed in a rectangular shape of 50×40 mm, and has a pattern forming area 4 inside. In the pattern forming region 4, a vapor deposition pattern 6 for forming a light emitting layer, which is composed of a large number of independent vapor deposition through holes 5, is formed.

The mask body 2 has a first metal layer 13 and a second metal layer 16 . Specifically, as shown in FIG. 6 , a second metal layer 16 is formed to cover the upper surface and side surfaces of the first metal layer 13 , and the first metal layer 13 and the second metal layer 13 between the vapor deposition through holes 5 16 (mask main body 2) has a stepped cross-sectional shape. By forming the second metal layer 16 so as to cover the surface of the first metal layer 13 in this way, the first metal layer 13 and the second metal layer 16 are simply stacked, and the Since the contact surface area between the layer 13 and the second metal layer 16 is increased, a laminated structure in which the first metal layer 13 and the second metal layer 16 are firmly adhered can be obtained. The thickness of the mask main body 2 is preferably in the range of 10 to 100 μm, and set to 20 μm in this embodiment. Specifically, the thickness t1 of the first metal layer 13 is preferably in the range of 5 to 90 μm, and is set to 16 μm in this embodiment, and the thickness t2 of the second metal layer 16 is preferably 10 μm or less. In the example, it was set to 4 μm. In addition, the upper surface of the first metal layer 13 refers to the vaporization source side, and the side surface of the first metal layer 13 refers to the surface facing the vapor deposition through hole 5 .

Each vapor deposition through-hole 5 is formed by connecting a small hole portion 5a and a large hole portion 5b formed to be larger than the opening shape of the small hole portion 5a. It has a rectangular shape with a front-rear length of 150 m and a left-right width of 50 μm when viewed from above, and the large hole portion 5b has a square shape with a front-rear length of 300 μm and a left-right width of 150 μm when viewed from above. have. The small hole portion 5a is on the deposition target substrate 30 side, and the large hole portion 5b is on the vaporization source side. These vapor deposition through holes 5 are arranged in parallel in the front-rear or left-right direction to form a vapor deposition pattern 6 . In this manner, the vapor deposition through-hole 5 is configured with the small hole portion 5a and the large hole portion 5b by forming the first metal layer 13 and the second metal layer 16 in a stepped shape in a cross-sectional view. This large hole 5b makes it possible to receive the organic material from the vaporization source at a wide angle, and it is possible to deal with the organic material incident from an oblique direction. can contribute to formation. Moreover, by forming the upper end peripheral edge portions (vaporization source side peripheral edge portions) of the second metal layer 16 facing the peripheral surfaces of the large hole portion 5b and the small hole portion 5a into rounded shapes, the large hole portion 5b and the small hole portion 5a In addition, the acceptance angle of the organic material can be widened, and a light-emitting layer with a more uniform height dimension can be obtained. The longitudinal sectional view of FIG. 1 does not show the appearance of the actual vapor deposition pattern 6, but shows it schematically.

A frame 3 for reinforcing the mask body 2 can be attached to the mask body 2 . The frame 3 is made of a material having a low coefficient of linear thermal expansion, such as Invar, which is a nickel-iron alloy, or Super Invar, which is a nickel-iron-cobalt alloy. The frame 3 is a molded product that is thicker than the mask main body 2 , and is inseparably and integrally joined to the outer peripheral edge 4 a of the pattern forming region 4 of the mask main body 2 by means of a metal layer 9 . Here, as shown in FIG. 9, 30 mask bodies 2 are held by one frame 3 . That is, the frame 3 has 30 openings 3a aligned on its plate surface, and one mask body 2 is attached to each opening 3a. The frame 3 has an opening 3a corresponding to the mask body 2 and is formed in a flat plate shape. The thickness dimension of the frame 3 is, for example, about 100 to 500 μm, and is set to 250 μm in this embodiment.

The reason why the Invar material and the Super Invar material are adopted as the material for forming the frame 3 is that their coefficient of linear expansion is extremely small, 2×10 -6 /°C or less, or less than 1×10 -6 /°C. This is because the dimensional change of the mask main body 2 due to is suppressed satisfactorily. For example, if the mask body 2 is made of nickel as described above, its coefficient of linear expansion is 12.80×10 -6 /° C. 3.20×10 −6 /° C., the linear expansion coefficient of 3.20×10 −6 /°C. It is inevitable that there will be a positional deviation between the vapor deposition position and the vapor deposition position of the vapor deposition material during actual vapor deposition. Therefore, if a material with a small coefficient of linear expansion, such as Invar, is used as the material for forming the frame 3 that holds the mask body 2, dimensional and shape changes caused by the expansion of the mask body 2 when the temperature rises. can be well suppressed, and the matching accuracy at room temperature can be maintained well even when the temperature is raised during vapor deposition.

In FIG. 6 , reference numeral 9 denotes a metal layer that joins the outer peripheral edge 4 a of the pattern forming region 4 of the mask body 2 and the frame 3 . The metal layer 9 is formed by plating, and is made of an electroformed metal such as nickel or nickel-cobalt alloy. If the outer peripheral edge 4a of the pattern forming region 4 of the mask body 2 and the frame 3 are bonded with the metal layer 9 in this way, it is inevitable that the mask body 2 and the frame 3 are bonded with an adhesive. Problems such as deterioration of the adhesive due to the action of the organic solvent used in the cleaning process etc. on the adhesive do not occur at all, and a good bonding state between the mask body 2 and the frame 3 is achieved. It can be maintained well for a long time.

In addition, in this embodiment, as shown in FIGS. 6 to 8, a large number of through holes 21 are provided along the entire circumference of the outer peripheral edge 4a of the pattern forming region 4 of the mask body 2, and the pattern formation of the mask body 2 is facilitated. It should be noted that the outer peripheral edge 4a of the region 4 and the frame 3 are integrally joined via the metal layer 9 formed so as to fill the through hole 21. As shown in FIG. That is, the metal layer 9 according to the present embodiment includes the upper surface of the outer peripheral edge 4a of the pattern formation region 4, the upper surface of the frame 3 and the side surface facing the pattern formation region 4, and the gap between the mask body 2 and the frame 3. In addition, it should be noted that it is grown and formed so as to fill the through holes 21 . In this way, when the mask body 2 and the frame body 3 are joined through the metal layer 9 grown and formed so as to fill the through hole 21, the joint strength between them 2 and 3 can be improved. As a result, it is possible to reliably prevent the mask body 2 from being carelessly removed from the frame 3 or misaligned. Therefore, it is possible to improve the reproducibility and vapor deposition accuracy of the light emitting layer.

Further, as shown in FIGS. 7 and 8, the four corners of the mask body 2 are chamfered in plan view. According to this, when the mask main body 2 thermally expands, it is possible to suppress concentration of stress on the corners. In FIGS. 7 and 8, the vapor deposition through hole 5 is represented as a straight hole instead of being composed of the small hole portion 5a and the large hole portion 5b.

10 to 12 show a method for manufacturing a vapor deposition mask according to this embodiment. First, as shown in FIG. 10(a), a photoresist layer 11 is formed on the surface of a matrix 10. Then, as shown in FIG. The matrix 10 is desirably made of a material having electrical conductivity and a low-temperature expansion coefficient, such as 42 alloy, invar, and SUS430 (stainless steel). The photoresist layer 11 is formed by laminating one or several sheets of a negative type photosensitive dry film resist to a predetermined height and by thermocompression bonding.

Next, on the photoresist layer 11, a pattern film (glass mask) having light-transmitting holes corresponding to the positions of the large holes 5b of the vapor deposition through-holes 5 and the through-holes 21 for increasing the adhesion strength is adhered. Exposure is performed by irradiating ultraviolet light, development and drying are performed, and unexposed portions are dissolved and removed, as shown in FIG. 10(b). A primary pattern resist 12 having straight resist bodies 12 a corresponding to the positions of the through holes 21 was formed on the master mold 10 .

Next, the mold 10 is placed in an electroforming bath prepared under predetermined conditions, and as shown in FIG. The uncovered surface (exposed area) was electroformed with a nickel-cobalt alloy, preferably in the range of 5-90 μm thickness, in this example 16 μm thickness, to form the first metal layer 13 . After forming the first metal layer 13, the primary pattern resist 12 (resist body 12a) is removed as shown in FIG. 10(d). Here, the first metal layer 13 may have a two-layer structure of a bright nickel layer and a matte nickel layer. In this case, an electrodeposited layer of bright nickel is electroformed on the matrix 10 to a thickness of 5 μm, and an electrodeposited layer of matt nickel is electroformed thereon to a thickness of 11 μm. In this way, if the first metal layer 13 has a two-layer structure, the bright nickel is less likely to stick to the master mold 10, and the final step of removing the vapor deposition mask 1 from the master mold 10 can proceed with good working efficiency. . In FIG. 10(d), reference numeral 13a denotes the first metal layer formed between the mask bodies 2.2.

Subsequently, as shown in FIG. 11(a), a photoresist layer 14 was formed over the entire surface of the matrix 10 including the region where the first metal layer 13 was formed. The photoresist layer 14 is formed by laminating one or several sheets of a negative type photosensitive dry film resist to a predetermined height and by thermocompression bonding.

Next, a pattern film having light-transmitting holes corresponding to the positions of the small holes 5a of the vapor deposition through-holes 5 is brought into close contact with the pattern film. By removing the part, a secondary pattern resist 15 having a straight resist body 15a corresponding to the position of the small hole portion 5a of the vapor deposition through hole 5 was formed on the master mold 10 as shown in FIG. 11(b). .

Next, the matrix 10 is placed in an electroforming bath prepared under predetermined conditions, and as shown in FIG. A second metal layer 16 was formed by electroforming a nickel-cobalt alloy on the surface (exposed region) of 13 not covered with the resist body 16a, preferably to a thickness of 10 μm or less, in this embodiment, to a thickness of 4 μm. . At this time, the second metal layer 16 formed in the portion facing the end (top or base) of the first metal layer 13 has an R shape. In addition, the end portion of the second metal layer 16 facing the vapor deposition through-hole 5 is also rounded. As for the curvature of the R (R), a desired R (R) can be obtained by adjusting the thickness of the second metal layer 16 . Then, by removing the secondary pattern resist 15 (resist body 15a), as shown in FIG. A mask body 2 having through holes 21 for increasing the bonding strength was obtained. As shown in FIGS. 7 and 8, each corner of the mask body 2 is chamfered in plan view. In FIG. 11(d), reference numeral 16a denotes a second metal layer formed between the mask bodies 2, 2, and is formed on the first metal layer 13a.

Subsequently, as shown in FIG. 12(a), a photoresist layer 17 was formed on the entire surface of the master mold 10 including the forming portions of the first metal layer 13 and the second metal layer 16 (mask body 2). This photoresist layer 17 is formed by laminating one or several sheets of a negative type photosensitive dry film resist to a predetermined height and by thermocompression bonding in the same manner as described above. Next, a pattern film having light-transmitting holes corresponding to the pattern forming regions 4 was brought into close contact, and then exposure was performed by irradiating ultraviolet rays. Thus, after obtaining a photoresist layer 17 in which the portion related to the pattern forming region 4 is exposed (17a) and the other portion is unexposed (17b), a matrix is formed as shown in FIG. 12(b). A frame body 3 was arranged on 10 so as to surround the first metal layer 13 and the second metal layer 16 . Here, the frame 3 was temporarily fixed on the master mold 10 by utilizing the adhesiveness of the unexposed photoresist layer 17b.

Next, as shown in FIG. 12(c), the unexposed photoresist layer 17b exposed on the surface was removed by dissolving to form a tertiary pattern resist 18 having a resist body 18a covering the pattern forming region. At this time, the unexposed photoresist layer 17b existing on the lower surface of the frame 3 remains on the matrix 10. Next, as shown in FIG.

Next, as shown in FIG. 12(d), the upper surface of the second metal layer 16 exposed on the surface related to the outer peripheral edge 4a of the pattern forming region 4 and the matrix exposed between the frame 3 and the second metal layer 16 are formed. Electrodeposited metal is electroformed on the surface of 10, on the surface of frame 3, and in through hole 21 to form metal layer 9, which metal layer 9 forms first electrodeposited layer 13 and second metal layer 16 ( The mask main body 2) and the frame 3 are integrally joined. Before forming the metal layer 9, the first electrodeposited layer 13 around the through hole 21, more specifically, the inner wall surface of the through hole 21 and the upper surface of the first electrodeposited layer 13 around the through hole 21 were subjected to , acid immersion, electrolytic treatment, strike plating, etc., the bonding strength between the treated portion and the metal layer 9 can be improved.

Finally, after peeling off the first metal layer 13, the second metal layer 16, and the metal layer 9 from the matrix 10, the first metal layer 13a existing on the lower surface of the frame 3 is peeled off from these metal layers. By removing the pattern resist 18 and the unexposed photoresist layer 17b, a vapor deposition mask 1 as shown in FIG. 6 was obtained.

(Third embodiment)
A vapor deposition mask according to a third embodiment of the present invention will be described with reference to FIGS. 13 to 15. FIG. The mask body 2 (vapor deposition mask 1) in each of the above-described embodiments is manufactured by using a conductive substrate as a matrix, forming a pattern resist on the surface thereof, and then electroforming it. It can also be manufactured using FIG. 13 and FIG. 14 show the manufacturing method of the vapor deposition mask according to this embodiment, and each step of the manufacturing method will be described below.

First, as shown in FIG. 13A, a matrix 40 having a metal film 41 formed thereon is prepared. For the matrix 40, for example, an insulating substrate such as a glass plate or a resin plate is used. Moreover, the metal film 41 is made of a conductive metal such as chromium or titanium. This metal film 41 is formed by depositing a metal film on the entire surface of the matrix 40 by sputtering, forming a resist pattern using a photolithography technique, and then etching away the metal film exposed from the resist pattern to remove the resist pattern. By removing, the metal film 41 is patterned on the surface of the matrix 40 . A first metal layer 44 and a second metal layer 45, which will be described later, are formed on the metal film 41 thus patterned. In this embodiment, a glass plate is used as the matrix 40, and chromium is used as the metal film 41. The thickness of the metal film 41 is 1 μm or less.

Next, as shown in FIG. 13(b), a photoresist layer 42 is formed on the surface of the matrix 40. Next, as shown in FIG. The photoresist layer 11 is formed by laminating one or several sheets of a negative type photosensitive dry film resist to a predetermined height and by thermocompression bonding.

Next, on the photoresist layer 42, a pattern film (glass mask) having light-transmitting holes corresponding to the formation positions of the first metal layer 44 is brought into close contact, followed by irradiation with ultraviolet light for exposure, development, and development. By performing each drying process and removing the unexposed portion, a pattern resist 43 having a straight resist body 43a corresponding to the formation position of the first metal layer 44 is formed as shown in FIG. 13(c). It was formed on the master mold 40 .

Next, the matrix 40 is placed in an electroforming bath prepared under predetermined conditions, and as shown in FIG. The uncovered surface (exposed area) was electroformed with a nickel-cobalt alloy, preferably in the range of 5-90 μm thickness, in this embodiment 16 μm thickness, to form the first metal layer 44 . Before forming the first metal layer 44, an oxide film, an organic film, a polymer film, or the like may be formed on the surface of the metal film 41 exposed from the resist body 43a.

Next, as shown in FIG. 14B, the pattern resist 43 (resist body 43a) is removed.

Next, the master mold 40 is placed in an electroforming bath prepared under predetermined conditions, and as shown in FIG. Then, the second metal layer 45 was formed by electroforming with a thickness of 4 μm in this embodiment. At this time, the second metal layer 45 formed in the portion facing the end (top or base) of the metal film 41 and the first metal layer 44 has an R shape. As a result, shadows caused by the upper peripheral edges of the large hole portion 5b and the small hole portion 5a can be eliminated as much as possible. As for the curvature of the R (R), a desired R (R) can be obtained by adjusting the thickness of the second metal layer 45 . Also, an oxide film, an organic film, a polymer film, or the like may be formed on the surfaces of the metal film 41 and the first metal layer 44 before forming the second metal layer 45 .

Finally, by peeling off the first metal layer 44 and the second metal layer 45 from the mother die 40, a vapor deposition passage hole 5 having a small hole portion 5a and a large hole portion 5b is provided as shown in FIG. A mask body 2 (evaporation mask 1) was obtained.

The mask main body 2 in the present embodiment has minute recesses 50 on the back surface side of the first metal layer 44 (on the deposition target substrate 30 side). The shape of the minute recesses 50 is formed corresponding to the shape of the metal film 41 . Due to the presence of such minute recesses 50, the outer peripheral portion of the minute recesses 50 (peripheral portion of the small hole portion 5a on the side of the substrate 30 to be vapor-deposited) protrudes. When vapor deposition is performed by placing the vapor deposition mask 1 on the vapor deposition target substrate 30, the vapor deposition mask 1 can be placed on the vapor deposition target substrate 30 with good adhesion due to the line contact between the periphery of the vapor deposition through hole 5 of the mask body 2 and the vapor deposition target substrate 30, and vaporization from the vaporization source. It is possible to prevent bleeding of the applied organic material and deposition on the back surface of the deposition mask 1 .

In each of the above-described embodiments, the metal layer 9 is formed under tension such that a tensile stress F1 acts to pull the first metal layer 13 and the second metal layer 16, that is, the mask body 2, toward the frame body 3 side. can do. Application of such tensile stress can be realized by adjusting the content ratio of carbon in the second type brightener added to the electroforming bath. As a result, the first metal layer 13 and the second metal layer 16 are stretched with a tension stress acting on the frame 3 through the metal layer 9, so that the ambient temperature during the vapor deposition operation Even with the rise, the expansion of the mask main body 2 due to the difference in thermal expansion coefficient from the frame 3 is absorbed, and the vapor deposition mask 1 is less likely to cause variations in dimensional accuracy due to heat, and the reproducibility and vapor deposition accuracy of the light emitting layer are improved. can contribute to improvement. Furthermore, by using a material that does not easily expand thermally as the frame 3 that holds the mask body 2, the influence of heat can be suppressed as much as possible.

In each of the above-described embodiments, the mask body 2, that is, the first metal layer 13 and the second metal layer 16, is formed in a state in which a tension is applied such that a stress F2 acting in the direction of contracting the mask inward is applied. You can also The tensile stress F2 is due to the temperature difference between the temperature of the electroformed layer (40 to 50° C.) and the normal temperature (20° C.) when creating the first metal layer 13 and the second metal layer 16. It can be realized by allowing the first metal layer 13 and the second metal layer 16 to contract. In more detail, after using a material with a low-temperature expansion coefficient such as 42 alloy, invar, and SUS430 (stainless steel) as the matrix 10, the first metal layer 13 and the second metal layer are formed in the electroformed layer at 40 to 50 ° C. When the layer 16 is formed, the expansion coefficient of the first metal layer 13 and the second metal layer 16 such as nickel or a nickel alloy is larger than that of the matrix 10, so stress acts on the matrix to cause it to expand ( Of course, the expansion of the metal layer 9 at this time is regulated by the matrix 10). However, at room temperature (20° C.), which is lower than the temperature of the electroformed layer (40-50° C.), the first metal layer 13 and the second metal layer 16 tend to contract inward and thus separate from the mold 10. As a result, the first metal layer 13 and the second metal layer 16, that is, the mask body 2 is subjected to a tensile stress F2 acting on the frame 3. As shown in FIG. As a result, the mask main body 2 can be kept taut without any wrinkles, so that the expansion of the mask main body 2 due to the difference in thermal expansion coefficient from that of the frame 3 can be prevented even when the ambient temperature rises during vapor deposition. Since the vapor deposition mask 1 is less likely to vary in dimensional accuracy due to heat, it can contribute to the improvement of the reproducibility and vapor deposition accuracy of the light-emitting layer. Moreover, by forming the through holes 21, by chamfering the corners of the mask body 2, and by making the frame 3 itself which holds the mask body 2 from a material which is difficult to thermally expand, variations in dimensional accuracy caused by heat are prevented. can be further suppressed, and further contribution can be made to improving the reproducibility and deposition accuracy of the light-emitting layer.

(Fourth embodiment)
In each of the above-described embodiments, the interface between the first metal layers 13 and 44 and the second metal layers 16 and 45 may be separated when the matrix is separated. In order to prevent this, before forming the second metal layers 16 and 45 on the first metal layers 13 and 44, the surfaces of the first metal layers 13 and 44 are subjected to surface activation treatment (acid immersion, cathode electrolysis, chemical etching, strike plating, etc.). In addition, as shown in FIG. 16, a protruding portion 60 is formed on the upper edge of the first metal layers 13 and 44, and the second metal layers 16 and 45 are formed on the first metal layers 13 and 44. , the separation between the first metal layers 13 and 44 and the second metal layers 16 and 45 can be prevented. When the first metal layers 13 and 44 are formed, the protruding portions 60 are formed by electroforming, or so-called overhanging, beyond the thickness of the resist bodies 12a and 43a. It is possible to obtain a shape in which an overhanging portion 60 having an eave-shaped cross section is integrally formed on the peripheral edge.

The number of mask bodies 2 included in the vapor deposition mask 1 is not limited to those shown in the above embodiments. Before or after removing the primary pattern resist 12, the second metal layer 16 may be formed after the first metal layer 13 is polished and smoothed. Before or after removing the secondary pattern resist 15 , the second metal layer 16 may be polished and smoothed, and then the tertiary pattern resist 18 may be formed in the pattern forming region 4 . As the material of the frame 3, in addition to a metal material such as the Invar material shown in the embodiment, a material having a low coefficient of linear thermal expansion that is as close as possible to the glass or the like that is the substrate to be vapor-deposited, such as glass or ceramic. can be selected. In this case, it is necessary to impart electrical conductivity to at least the surface of these materials. Furthermore, while the formed vapor deposition mask 1 is in a tensioned state, a fixing frame made of stainless steel, aluminum, or the like may be separately fixed to the outer peripheral edge thereof by a known method. However, when each mask body 2 is held by the frame 3 while being tensioned through the metal layer 9 as in the embodiment, a so-called frameless configuration that does not require a fixed frame is possible. Moreover, the mask according to the present invention can be applied as a mask other than a vapor deposition mask.

1 vapor deposition mask (mask)
2 mask main body 3 frame 4 pattern formation region 4a outer peripheral edge of pattern formation region 5 vapor deposition through hole (through hole)
6 vapor deposition pattern (pattern)
9 metal layer 10 matrix 12 primary pattern resist 13 first metal layer 15 secondary pattern resist 16 second metal layer 17 pattern film 18 tertiary pattern resist 21 through hole 40 matrix 43 pattern resist 44 first metal layer 45 second metal Layer 50 Microrecess 60 Overhang

Claims (8)

A mask in which a mask body 2 is provided with a pattern 6 consisting of a large number of independent through holes 5,
The mask body 2 has first metal layers 13 and 44 and second metal layers 16 and 45,
A protruding portion 60 is formed on the peripheral edge of the upper end facing the through hole 5 in the first metal layers 13 and 44,
The projecting portion 60 has a surface formed continuously with the upper surfaces of the first metal layers 13 and 44 and a lower surface parallel to the upper surfaces of the first metal layers 13 and 44,
In the thickness direction of the mask body 2, the lower surface of the projecting portion 60 is provided at a position higher than the center of the thickness of the first metal layers 13 and 44,
A mask, wherein the second metal layers 16 and 45 are formed so as to cover the top and side surfaces of the first metal layers 13 and 44 and the top and bottom surfaces of the projecting portion 60 .
2. A mask according to claim 1, wherein the surfaces of said first metal layers (13, 44) are subjected to a surface activation treatment. By forming the second metal layers 16 and 45 from the side surfaces of the first metal layers 13 and 44 toward the center of the through hole 5, the cross-sectional shape of the mask main body 2 between the through holes 5 is stepped. 3. The mask according to claim 1 or 2, characterized in that: 4. The structure of claim 1, wherein the through hole 5 is formed by connecting a small hole portion 5a and a large hole portion 5b formed to be larger than the opening shape of the small hole portion 5a. A mask according to any of the above. 5. The mask according to claim 4, wherein the upper peripheral edge of said large hole portion (5b ) is rounded. A mask body 2 is provided with a pattern 6 consisting of a large number of independent through holes 5. The mask body 2 has a first metal layer 13 and a second metal layer 16. A protruding portion 60 is formed, and the protruding portion 60 has a lower surface parallel to the upper surface of the first metal layer 13 . The second metal layer 16 is provided at a position higher than the center of the thickness of the first metal layer 13, and covers the upper surface and side surfaces of the first metal layer 13 and the surface and the lower surface of the projecting portion 60. A method of manufacturing a formed mask, comprising:
a step of forming a primary pattern resist 12 having a resist body 12a on the surface of the master mold 10;
a step of forming the first metal layer 13 on the surface of the master mold 10 not covered with the resist body 12a so as to exceed the thickness of the resist body 12a;
a step of forming a secondary pattern resist 15 having a resist body 15a on the surface of the master mold 10;
and forming the second metal layer 16 on surfaces of the master mold 10 and the first metal layer 13 that are not covered with the resist body 15a. A mask body 2 is provided with a pattern 6 consisting of a large number of independent through holes 5. The mask body 2 has a first metal layer 44 and a second metal layer 45. A protrusion 60 is formed, and the protrusion 60 has a lower surface parallel to the upper surface of the first metal layer 44 . The second metal layer 45 is provided at a position higher than the center of the thickness of the one metal layer 44, and covers the upper and side surfaces of the first metal layer 44 and the surface and the lower surface of the projecting portion 60. A method of manufacturing a formed mask, comprising:
a step of preparing a matrix 40 in which a metal film 41 is patterned;
a step of forming a pattern resist 43 having a resist body 43a on the surface of the master mold 40;
forming the first metal layer 44 on the surface of the metal film 41 beyond the thickness of the resist body 43a;
and forming the second metal layer 45 on the surfaces of the metal film 41 and the first metal layer 44 . A method of manufacturing a mask, wherein the surface of the first metal layer (13) according to claim 6 or the surface of the first metal layer (44) according to claim 7 is subjected to surface activation treatment.

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