JP5328217B2 - Mask and mask manufacturing method - Google Patents

Description

The present invention relates to a metal mask used for, for example, screen printing with a substantially uniform thickness, ball mounting, vapor deposition, or the like, and a manufacturing method thereof.

  There is a mask for screen printing having a two-layer structure in which a layer formed by plating and having a printing pattern opening and a layer formed by plating and having a mesh pattern opening are laminated.

Moreover, when manufacturing a mask, there exists the method of forming a resist in the part used as the printing pattern opening on an electroconductive base material, and performing electroplating. This method increases the current density in the vicinity of the resist when electrolytic plating is performed. As a result, the plating film near the resist is formed thicker than other portions. That is, the mask thickness is not uniform. In other words, a difference occurs in the thickness between the opening portion of the mask and the portion having no opening. For this reason, the strength of the mask is weak.
Further, when the resist is concentrated on a part, the current density is different between the vicinity of the center of the concentrated resist and the vicinity of the outside. As a result, the plating film on the outer portion of the concentrated resist becomes thinner than the plating film near the center of the concentrated resist. That is, when the openings of the mask are formed in a concentrated manner, the mask thickness at the center and outside of the portion where the openings are formed is not uniform. For this reason, variations occur in the amount of solder printed between the center and the outside of the portion where the opening is formed.

Further, in a two-layer screen printing mask in which a layer having a printing pattern opening and a layer having a mesh pattern opening are laminated, the printing pattern opening is provided in order to solve the problem that the mask thickness is not uniform. There is a method of forming a dummy opening in a layer (see Patent Document 1).
That is, when forming a layer having a printed pattern opening, a dummy resist is formed in addition to the portion to be the printed pattern opening, and electrolytic plating is performed. By forming a dummy resist, concentration of current density is prevented and the thickness of the plating film is made uniform. Since the mesh opening is not formed in the portion where the dummy opening is formed, the dummy opening portion is not printed.
JP 2004-25709 A

For example, a ball mounting mask or the like does not have a layer having a mesh opening. Therefore, when a dummy opening is provided to make the mask thickness uniform, printing is also performed on the dummy opening.
An object of the present invention is to provide a mask having a uniform thickness that is not printed on a portion other than a print pattern, for example, in a mask having no mesh such as a ball-mounted mask.

The mask according to the present invention is formed by , for example, laminating a first mask layer formed by plating and having a printing part opening, and a second mask layer formed by plating and having a printing pattern opening corresponding to the printing pattern. The first mask layer has a printing part having a printing part opening formed so as to overlap substantially the entire surface of the printing pattern opening, and a non-printing part having no printing part opening, the second mask layer, in addition to the above print pattern opening possess the above the non-printing part and the overlapped part dummy opening of the first mask layer, said first mask layer having a printing opening The thickness of the non-printing portion that does not have the printing portion opening is slightly smaller than the thickness of the printing portion, and the second mask layer has the thickness of the portion having the printing pattern opening and the dummy opening. Same as part thickness The first mask layer is formed with a thinner film than the second mask layer, so that the difference between the thickness of the printed portion of the first coating and the thickness of the non-printed portion is not noticeable. The thickness of the portion having the printed pattern opening and the thickness of the portion having the dummy opening are close to the same when viewed from the whole mask .

  The printing portion opening of the first mask layer has substantially the same size and the same shape as the printing pattern opening.

  The dummy opening of the second mask layer has an area substantially the same as the area of the print pattern opening.

The method for producing a mask according to the present invention includes, for example, forming a first resist having a printed pattern shape on a base material, and plating the base material except for the region where the first resist is formed. The substrate includes a printing unit having a printing unit opening and a non-printing unit having no printing unit opening, and has the printing unit opening rather than the thickness of the printing unit having the printing unit opening. A step of forming a first mask layer by plating, in which the thickness of the non-printing portion is slightly reduced , a printed pattern shape corresponding to the printing portion on the first mask layer, and the non-printing portion Forming a second resist having a pattern shape of a corresponding dummy opening, and having a printed pattern opening on the first mask layer except for the region where the second resist is formed and the thickness of the part, da Removing the step in which the thickness of the portion having an opening over is formed by plating a second mask layer formed in the same thickness, and the first resist and the second resist, the first A step of peeling the base material from the first mask layer and the second mask layer , wherein the first mask layer is formed as a thin film compared to the second mask layer, thereby The difference between the thickness of the printed portion of the film and the thickness of the non-printed portion is inconspicuous, and the thickness of the portion having the printed pattern opening and the thickness of the portion having the dummy opening when viewed from the whole mask. It is characterized by approaching the same .

The method for producing a mask according to the present invention includes, for example, forming a first resist having a printed pattern shape on a base material, and plating the base material except for the region where the first resist is formed. The substrate includes a printing unit having a printing unit opening and a non-printing unit having no printing unit opening, and has the printing unit opening rather than the thickness of the printing unit having the printing unit opening. A thickness of the non-printing part is slightly reduced, the step of forming a first mask layer by plating, the step of removing the first resist, the printing part on the first mask layer, Except for the step of forming a second resist having a corresponding printed pattern shape and a pattern shape of a dummy opening corresponding to the non-printing portion, and the region where the second resist is formed, the first resist On the mask layer Forming a second mask layer formed by plating so that the thickness of the portion having the printed pattern opening is the same as the thickness of the portion having the dummy opening , and removing the second resist And peeling the substrate from the first mask layer and the second mask layer , wherein the first mask layer is formed with a thinner film than the second mask layer. Therefore, the difference between the thickness of the printed portion of the first film and the thickness of the non-printed portion is inconspicuous, and the thickness of the portion having the printed pattern opening and the portion having the dummy opening when viewed from the entire mask. It is characterized in that the thickness of each of the two approaches the same .

  According to the mask and the mask manufacturing method of the present invention, the mask thickness can be made uniform in a mask having no mesh such as a ball-mounted mask.

Embodiment 1 FIG.
First, the shape of the mask 1 according to the first embodiment will be described with reference to FIGS.

FIG. 1 is a diagram showing a state in which the mask 1 is viewed from the printing side (work side). The print pattern opening 2 formed in the mask 1 is an opening corresponding to the print pattern. The dummy opening 3 is an opening that is not a printing pattern.
FIG. 2 is a diagram illustrating a state in which the mask 1 is viewed from the ink side. The ink side is the side on which the squeegee slides if it is a mask for printing with a squeegee. The printing part opening 4 formed in the mask 1 is an opening connected to the printing pattern opening 2.
3 is a cross-sectional view taken along line AA ′ shown in FIG. As shown in FIG. 3, the mask 1 includes a layer having a printing portion opening 4 (first mask layer 13), and a layer having a printing pattern opening 2 and a dummy opening 3 (second mask layer 16). With two layers. The printing part opening 4 is provided in one-to-one correspondence with the printing pattern opening 2. Moreover, the printing part opening 4 is formed in the substantially same magnitude | size as the printing pattern opening 2, and is piled up and provided in the substantially same position. In other words, the printing part opening 4 is in a state of covering the entire surface of the printing pattern opening 2. That is, the cross-sectional shape of the printing part opening 4 and the printing pattern opening 2 is the same. On the other hand, the printing part opening 4 is not connected to the dummy opening 3. That is, the dummy opening 3 is closed on the ink side and does not penetrate.
When printing is performed using the mask 1, the ink moves from the ink side to the printing side through the printing unit opening 4 and adheres to the work. The dummy opening 3 is closed on the ink side and is not printed.

As shown in FIG. 3, the first mask layer 13 has a portion (non-printing portion) that does not have the printing portion opening 4 than the thickness (W1) of the portion (printing portion) that has the printing portion opening 4. The thickness (W2) is slightly thin. The reason for this will be described later.
On the other hand, in the second mask layer 16, the thickness (W3) of the portion having the printed pattern opening 2 and the thickness (W4) of the portion having the dummy opening 3 are substantially the same. The reason for this will also be described later.
When viewed as a whole of the mask 1, it is desirable that the thickness (W1 + W3) of the portion having the printed pattern opening and the thickness (W2 + W4) of the portion having the dummy opening 3 are substantially the same. That is, importance is attached to the uniformity of the thickness of the mask 1. Therefore, the first mask layer 13 is formed as thin as possible. In particular, the first mask layer 13 is formed with a thinner film than the second mask layer 16. By making the first mask layer 13 thinner than the second mask layer 16, the difference between the thickness (W1) of the printed portion of the first mask layer 13 and the thickness (W2) of the non-printed portion is masked. It shall be inconspicuous when viewed as a whole. As a result, it can be said that the thickness (W1 + W3) of the portion having the printed pattern opening and the thickness (W2 + W4) of the portion having the dummy opening 3 are substantially the same when viewed from the mask 1 as a whole.
Further, it is desirable that the width (W5) of the printing pattern opening 2 is substantially the same as the width (W7) of the dummy opening 3. Although details will be described later, the thickness (W3) of the portion having the print pattern opening can be obtained by making the width (W5) of the print pattern opening 2 substantially the same as the width (W7) of the dummy opening 3 in this way. The thickness (W4) of the portion having no printed pattern opening can be made substantially the same. That is, it is desirable that the cross-sectional shapes of the printing part opening 4, the printing pattern opening 2, and the dummy opening 3 are the same. Further, the area of the print pattern opening 2 and the area of the dummy opening 3 may be substantially the same.
Further, as described above, since the printing portion opening 4 is formed to have substantially the same size as the printing pattern opening 2, the width (W6) of the printing portion opening 4 is the width (W5) of the printing pattern opening 2. Is almost the same.

Next, a method for manufacturing the mask 1 according to the first embodiment will be described with reference to FIGS.
First, as shown in FIG. 4, a base material 10 is prepared, and a resist 11 (photosensitive resin, first resist) is laminated thereon. The material of the base material 10 can use conductive base materials, such as SUS (stainless steel, Stainless Used Steel), an iron plate, aluminum, for example. Alternatively, a non-conductive base material on which a conductive film is formed may be used. For example, a base material obtained by vapor-depositing a conductive material such as Ni, Cr, or ITO (Indium Tin Oxide) film on glass may be used.

  Next, as shown in FIG. 5, the pattern film 12 having the pattern of the printing portion opening 4 is superimposed on the resist 11 and exposed. That is, the exposed portion 12-1 of the print pattern of the pattern film 12 is exposed. Thus, the method is not limited to the method of exposing the print pattern to the resist using a film, and the pattern of the printing portion opening 4 may be directly drawn on the resist using an ultraviolet laser or the like. Then, the pattern film 12 is removed and developed. Then, as shown in FIG. 6, the resist 11 is formed in the pattern shape of the printing unit opening 4. As shown in FIG. 7, the first mask layer 13 is formed on the surface of the substrate 10 except for the region where the resist 11 is formed by plating nickel or the like. Then, when the resist 11 is peeled (removed), the printing portion opening 4 is formed in the first mask layer 13 as shown in FIG.

Next, as shown in FIG. 9, a resist 14 is laminated on the first mask layer 13. Then, as shown in FIG. 10, a pattern film 15 having a printing pattern (pattern of printing pattern openings 2) and a pattern of dummy openings 3 is overlaid on the resist 14 and exposed. That is, the exposed portion 15-1 of the print pattern of the pattern film 15 is exposed. Here, as described above, the print pattern may be directly drawn on the resist using an ultraviolet laser or the like. Then, the pattern film 15 is removed and developed. Then, as shown in FIG. 11, the resist 14 is formed in a printed pattern shape and a pattern shape of the dummy opening 3. As shown in FIG. 12, the second mask layer 16 is formed on the surface of the first mask layer 13 except for the region where the resist 14 is formed by plating nickel or the like. Then, the resist 14 is peeled (removed), and the substrate 10 is peeled from the first mask layer 13 and the second mask layer 16. Then, as shown in FIG. 13, the first mask layer 13 in which the printing part opening 4 was formed and the second mask layer 16 in which the printing pattern opening 2 and the dummy opening 3 were formed were laminated. A mask is manufactured.

Here, as shown in FIG. 7, when the first mask layer 13 is formed by plating, the vicinity of the resist 11 becomes thick and the other portions become thin. That is, as described above, the first mask layer 13 has a portion (non-printing portion) that does not have the printing portion opening 4 than the thickness (W1) of the portion (printing portion) that has the printing portion opening 4. The thickness (W2) is slightly reduced. This is because the current density in the vicinity of the resist 11 is higher than in other portions when plating is performed.
On the other hand, as shown in FIG. 12, even if the second mask layer 16 is formed by plating, the entire second mask layer 16 has a substantially uniform thickness. That is, as described above, in the second mask layer 16, the thickness (W3) of the portion having the print pattern opening 2 and the thickness (W4) of the portion having the dummy opening 3 are substantially the same. It is. This is because the current density is substantially uniform as a whole because the resist 14 is formed not only in the printed pattern shape but also in the pattern of the dummy openings 3. By providing the dummy openings 3 uniformly in a portion where no print pattern exists, the current density can be made more uniform. Further, by making the dummy openings 3 have the same shape as the printed pattern openings 2, the current density can be made more uniform, and the entire thickness of the second mask layer 16 can be made substantially uniform. Similarly, even if the dummy openings 3 are not the same shape as the printed pattern openings 2 but have the same area, the current density can be made uniform, and the second mask layer 16 has a substantially uniform thickness as a whole. Can do.

Further, when the printing pattern opening 2 is smaller than the printing part opening 4, the resist 13 cannot be formed on the printing part opening 4 as shown in FIG. 11. Therefore, in the above-described mask manufacturing method, it is necessary to make the printing pattern opening 2 slightly larger than the printing portion opening 4. That is, in the above description, the printing pattern opening 2 and the printing part opening 4 are substantially the same size, but this substantially the same size means that the printing pattern opening 2 is about 10 μm larger than the printing part opening 4. It means to include cases.
Alternatively, as shown in FIG. 8, the resist 11 may be laminated without removing the resist 11 and leaving the resist 11. In this case, the printing pattern opening 2 may be smaller than the printing part opening 4. That is, in this case, the resist 11 is removed together with the resist 14 in the step shown in FIG. Further, in this case, since the second mask layer 16 needs to be formed also on the resist 11, it is necessary to form a conductive film on the resist 11 except at least a region where the resist 14 is formed.

That is, the mask according to Embodiment 1 is a mask in which two layers that do not have a mesh pattern are stacked. A dummy opening 3 is formed in the second mask layer 16 that is a layer on the printing side (work side). By forming the dummy opening 3 in the second mask layer 16, the thickness of the second mask layer 16 is made uniform. On the other hand, the first mask layer 13 which is a layer on the ink side does not have the dummy opening 3 and the thickness is not uniform. However, the thickness of the first mask layer 13 is thinner than the thickness of the second mask layer 16, and the thickness of the first mask layer 13 is very thin. Therefore, the unevenness in the thickness of the first mask layer 13 is almost negligible.
That is, the mask according to Embodiment 1 is a mask that does not have a mesh pattern with a substantially uniform thickness.

As described above, it is desirable that the pattern of the dummy openings 3 has the same shape as the printed pattern openings 2. In particular, when the print pattern opening 2 has a constant pattern, it is desirable to provide the dummy opening 3 to repeat the constant pattern. The reason is the same as described above, because the current density can be made more uniform. That is, in the case of the mask 1 having a plurality of chip patterns 2-1 having a plurality of printed pattern openings 2, it is desirable that the pattern of the dummy openings 3 has the same shape as the chip pattern 2-1.
An example is shown in FIGS. FIG. 14 is a diagram illustrating a state in which the mask 1 having a plurality of chip patterns 2-1 is viewed from the printing side (working side). FIG. 15 is a diagram illustrating a state in which the mask 1 having a plurality of chip patterns 2-1 is viewed from the ink side. In FIGS. 14 and 15, a portion indicated by a bold line indicates a printing pattern opening 2 and a chip pattern 2-1 having a plurality of printing pattern openings 2. Here, the chip patterns 2-1 are all the same pattern. In FIG. 14, the thin line indicates the dummy opening 3 and the set of dummy openings 3-1 corresponding to the chip pattern 2-1. Here, the chip pattern 2-1 and the set of dummy openings 3-1 are the same pattern.
That is, it is desirable that the pattern of the dummy openings 3 be provided so as to have the same area when divided from the print pattern openings 2 within a predetermined range.

  It is desirable to provide a plurality of dummy openings 3 outside the print pattern openings 2. In the above description, a simplified diagram is used for explanation, but in actuality, plating is performed as shown in FIG. That is, the plating 18 is gradually thinned from the portion where the resists 17 are dense to the portion where the resists 17 are not present. Therefore, the plating 18 is not sufficiently applied to the portion to be the printing pattern opening 2, which causes a printing defect. Therefore, as shown in FIG. 17, by providing a plurality of resists 19 of the dummy openings 3 outside the resist 17 of the printing pattern openings 2, the plating 18 is sufficient in the portions to be the printing pattern openings 2. That is, by providing the dummy opening 3, the plating 18 is sufficiently applied to the portion to be the printed pattern opening 2. Then, the portion where the plating 18 is not sufficiently formed is generated not in the portion to be the printed pattern opening 2 but in the portion of the dummy opening 3. The same applies to the example shown in FIG. That is, as shown in FIG. 14, it is desirable to provide a plurality of repetitions 3-1 of the dummy openings 3 outside the print pattern openings 2.

  Here, as can be seen from the description of FIG. 16 and FIG. 17, in the above description, the second mask layer 16 has been described as having a substantially uniform thickness for the sake of simplicity. The thickness outside the 16 dummy openings 3 gradually decreases. That is, for example, in FIG. 3, the entire thickness of the second mask layer 16 is shown to be uniform, but actually, the thickness outside the dummy opening 3 gradually increases as in FIGS. 16 and 17. It becomes thinner. That is, the entire second mask layer 16 described above has a substantially uniform thickness, strictly speaking, that at least the printed portion of the second mask layer 16 has a substantially uniform thickness as a whole.

  In the above description, the expression that the dummy opening 3 is provided outside the printing unit is used. Here, providing the dummy opening 3 outside the printing unit means that the dummy opening 3 is also provided between the printing unit when a plurality of printing units are present at intervals. Is included.

To summarize the above, the mask manufacturing method according to this embodiment includes, for example, a step of forming a first resist having a printed pattern shape on a substrate;
A first mask provided with a printing part having an opening and a non-printing part having no opening on the base by plating the base except the region where the first resist is formed. Forming a layer by plating;
A second resist having a printed pattern shape is formed on the region where the first resist is formed, and a third resist having a predetermined pattern is formed on the surface of the non-printing portion of the first mask layer. Steps,
Forming a second mask layer by plating on the first mask layer, except for a region where the second resist and the third resist are formed;
Removing the first resist, the second resist, and the third resist;
It can be said that the method includes a step of peeling the base material from the first mask layer and the second mask layer.

The figure which shows the state which looked at the mask 1 from the printing side (work side). The figure which shows the state which looked at the mask 1 from the ink side. A-A 'sectional view shown in FIG. The figure which shows the state which laminated the resist 11 on the base material 10. FIG. The figure which shows the state which mounts the pattern film 12 on the resist 11, and exposes. The figure which shows the state in which the resist 11 was formed in the shape of the printing part opening 4. FIG. The figure which shows the state which plated and formed the 1st mask layer 13 on the surface of the base material 10. FIG. The figure which shows the state by which the resist 11 was peeled (removed) and the printing part opening 4 was formed in the 1st mask layer 13. FIG. The figure which shows the state which laminated the resist 14 on the 1st mask layer 13. FIG. The figure which shows the state which mounts the pattern film 15 on the resist 14, and exposes. The figure which shows the state in which the resist 14 was formed in the printing pattern shape and the pattern shape of the dummy opening 3. FIG. The figure which shows the state which gave plating and formed the 2nd mask layer 16 on the surface of the 1st mask layer 13. FIG. The figure which shows the state which peeled the resist 14 and peeled the base material 10 from the 1st mask layer 13 and the 2nd mask layer 16. FIG. The figure which shows the state which looked at the mask 1 which has the pattern 2-1 of a some chip | tip from the printing side (work | work side). The figure which shows the state which looked at the mask 1 which has the pattern 2-1 of a some chip | tip from the ink side. The figure which shows the formation state of the plating when not providing the dummy opening 3. FIG. The figure which shows the formation state of the plating at the time of providing the dummy opening 3. FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Mask, 2 Print pattern opening, 3 Dummy opening, 4 Print part opening, 10 Base material, 11, 14, 17, 19 Resist, 12, 15 Pattern film, 13 1st mask layer, 16 2nd mask layer 18 Plating.

Claims (5)

A mask in which a first mask layer formed by plating and having a printing part opening and a second mask layer formed by plating and having a printing pattern opening corresponding to the printing pattern are laminated;
The first mask layer has a printing part having a printing part opening formed so as to overlap the substantially entire surface of the printing pattern opening, and a non-printing part having no printing part opening,
The second mask layer, in addition to the above print pattern opening possess the above the non-printing part and the overlapped part dummy opening of the first mask layer,
In the first mask layer, the thickness of the non-printing part not having the printing part opening is slightly thinner than the thickness of the printing part having the printing part opening,
In the second mask layer, the thickness of the portion having the printed pattern opening and the thickness of the portion having the dummy opening are the same thickness,
The first mask layer is formed with a thinner film than the second mask layer, so that the difference between the thickness of the printed portion of the first coating and the thickness of the non-printed portion is inconspicuous. A mask in which the thickness of the portion having the printed pattern opening and the thickness of the portion having the dummy opening are close to each other when viewed in FIG.   The mask according to claim 1, wherein the printing portion opening of the first mask layer has substantially the same size and the same shape as the printing pattern opening.   3. The mask according to claim 1, wherein the dummy opening of the second mask layer has substantially the same area as the printed pattern opening. Forming a first resist having a printed pattern shape on a substrate;
By plating the base material except for the region where the first resist is formed, the base material is provided with a printing part having a printing part opening and a non-printing part having no printing part opening. Forming a first mask layer by plating in which the thickness of the non-printing portion not having the printing portion opening is made slightly thinner than the thickness of the printing portion having the printing portion opening ;
Forming a second resist having a printed pattern shape corresponding to the printed portion and a dummy opening pattern shape corresponding to the non-printed portion on the first mask layer;
Except for the region where the second resist is formed, the thickness of the portion having the printed pattern opening on the first mask layer and the thickness of the portion having the dummy opening are formed to the same thickness. Forming a second mask layer by plating;
Removing the first resist and the second resist;
Peeling the substrate from the first mask layer and the second mask layer ,
The first mask layer is formed with a thinner film than the second mask layer, so that the difference between the thickness of the printed portion of the first coating and the thickness of the non-printed portion is inconspicuous. The mask manufacturing method is characterized in that the thickness of the portion having the printed pattern opening and the thickness of the portion having the dummy opening approach the same when viewed in FIG . Forming a first resist having a printed pattern shape on a substrate;
By plating the base material except for the region where the first resist is formed, the base material is provided with a printing part having a printing part opening and a non-printing part having no printing part opening. Forming a first mask layer by plating in which the thickness of the non-printing portion not having the printing portion opening is made slightly thinner than the thickness of the printing portion having the printing portion opening ;
Removing the first resist;
Forming a second resist having a printed pattern shape corresponding to the printed portion and a dummy opening pattern shape corresponding to the non-printed portion on the first mask layer;
Except for the region where the second resist is formed, the thickness of the portion having the printed pattern opening on the first mask layer and the thickness of the portion having the dummy opening are formed to the same thickness. Forming a second mask layer by plating;
Removing the second resist;
Peeling the substrate from the first mask layer and the second mask layer ,
The first mask layer is formed with a thinner film than the second mask layer, so that the difference between the thickness of the printed portion of the first coating and the thickness of the non-printed portion is inconspicuous. The mask manufacturing method is characterized in that the thickness of the portion having the printed pattern opening and the thickness of the portion having the dummy opening approach the same when viewed in FIG .

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