JP6680638B2 - Mask and wiring board manufacturing method - Google Patents

Description

  The present invention relates to a mask used for filling a through hole of a green sheet with a filler, and a wiring board manufacturing method for manufacturing a wiring board using the mask.

  2. Description of the Related Art Conventionally, a wiring board manufacturing method is known in which a plurality of through holes provided in a green sheet for an insulating substrate are filled with a filler such as metallized ink and then fired to manufacture the wiring board (for example, patents). Reference 1).

In this conventional technique, for example, as shown in FIG. 9, the through holes P2 of the green sheet P1 are filled with the metallized ink P3.
Specifically, first, a metal mask P5 in which a through hole P4 is formed at a position corresponding to the through hole P2 of the green sheet P1 is prepared, and this metal mask P5 is used as the through hole P4 and the green sheet P1. Are arranged on the green sheet P1 so as to be aligned with the through holes P2. Then, the metallized ink P3 is arranged on the metal mask P5, and the squeegee P6 is moved in the arrow X direction along the surface of the metal mask P5. As a result, the metallized ink P3 is moved in the direction of the arrow Y to fill the through hole P2 of the green sheet P1 through the through hole P4 of the metal mask P5.

JP, 2012-28545, A

  However, in the above-described conventional technique, when the squeegee P6 passes through the opening on the upper surface side of the through hole P4 of the metal mask P5, the metallized ink P3 is passed through the through hole P4 of the metal mask P5 only by the pressure of the squeegee P6. Since the green sheet P1 is extruded into the through hole P2 of the green sheet P1, the metallized ink P3 may not be sufficiently filled up to the vicinity of the lower surface of the green sheet P1.

  If the metallized ink P3 is not sufficiently filled in the through holes P2 of the green sheet P1, especially in the vicinity of the opening on the lower surface side of the through holes P2, it is filled when the green sheet P1 is baked to manufacture a wiring board. However, there is a problem that defects such as voids are generated in a portion (that is, a lower portion of the via) where the above is not sufficient.

  When defects such as voids occur, for example, when a conductive layer is formed so as to cover the surface of the via, unevenness is generated in the conductive layer, or conduction with other vias stacked with the via is insufficient. Such problems may occur.

  The present invention has been made in view of the above problems, and an object thereof is to mask a through hole of a green sheet or the like that can be sufficiently filled with a filler, and wiring using the mask. It is to provide a method for manufacturing a substrate.

(1) A first aspect of the present invention relates to a mask having a front surface and a back surface and having a through hole penetrating the front surface and the back surface.
In this mask, the surface of the mask has a groove extending from the surface to the through hole, and the portion of the groove opening to the through hole faces a part of the inner peripheral surface of the through hole.

  As described above, in the first aspect, the surface of the mask has the groove extending from the surface to the through hole, and the portion of the groove opening into the through hole faces a part of the inner peripheral surface of the through hole. There is. Therefore, by using this mask, the via holes can be formed by sufficiently filling the through holes of the member to be filled such as the green sheet with the filling material such as metallized ink.

  Specifically, when the squeegee passes through the opening on the upper surface side of the through hole of the mask by moving the filler with a squeegee, for example, the filler is reliably introduced into the through hole of the mask through the groove. At the same time, it hits the inner peripheral surface of the through hole facing the groove and is sufficiently pushed into the through hole of the mask.

  Then, the filling material pushed into the through hole of the mask is further pushed into the through hole of the member to be filled. As a result, the filling material is sufficiently filled up to the lower surface of the member to be filled (that is, the surface opposite to the mask) and its vicinity.

  Thus, in the first aspect, by using the mask having the above-described configuration, the filling material can be sufficiently filled in the through hole of the filled member, particularly in the vicinity of the opening on the lower surface side of the through hole. For example, when a wiring board is manufactured by firing a green sheet, it is possible to suppress the occurrence of defects such as voids in a portion where filling is insufficient (that is, the lower portion of the via).

  As a result, for example, when the conductive layer is formed so as to cover the surface of the via, it is possible to suppress the occurrence of irregularities in the conductive layer, and to sufficiently ensure conduction with other vias stacked with the via. Has a remarkable effect. Further, when the via is exposed on the surface of the wiring board, there is an advantage that unevenness on the board surface can be suppressed and smoothed.

(2) In the second aspect of the present invention, the groove is formed so as to extend in one direction with respect to the through hole when seen in a plan view from the front surface side of the mask.
In the second aspect, since the groove is formed so as to extend in one direction with respect to the through hole, the filler can be reliably introduced into the through hole of the mask by squeegeeing along this direction. As a result, the filling material can be sufficiently filled into the through hole of the filling target member through the through hole of the mask.

(3) In the third aspect of the present invention, the width of the portion of the groove that opens in the through hole is equal to or smaller than the hole diameter of the through hole in a plan view seen from the front surface side of the mask.
In the third aspect, since the width of the portion of the groove that opens in the through hole is equal to or smaller than the hole diameter of the through hole, the filler introduced into the through hole along the groove must be reliably pushed into the through hole of the mask. You can As a result, the filling material can be sufficiently filled into the through hole of the filling target member through the through hole of the mask.

(4) In the fourth aspect of the present invention, the groove has a bottom surface, and the bottom surface has an inclined surface in which the distance between the surface and the bottom surface increases toward the through hole.
In the fourth aspect, the bottom surface of the groove has an inclined surface in which the distance between the surface and the bottom surface increases toward the through hole, so that the filler introduced into the through hole along the groove is applied to the through hole of the mask. It can be pushed in efficiently. As a result, the filling material can be sufficiently filled into the through hole of the filling target member through the through hole of the mask.

(5) In the fifth aspect of the present invention, the bottom surface has an inclined surface and has a flat surface parallel to the surface and extending from the end of the inclined surface on the through hole side to the through hole.
In the fifth aspect, since the bottom surface of the groove has the inclined surface and the flat surface described above, the filler introduced into the through hole along the groove can be efficiently pushed into the through hole of the mask. As a result, the filling material can be sufficiently filled into the through hole of the filling target member through the through hole of the mask.

(6) A sixth aspect of the present invention relates to a wiring board manufacturing method for manufacturing a wiring board using the mask according to any one of the first to fifth aspects.
In this wiring board manufacturing method, a first step of preparing the mask according to any one of the first to fifth aspects, a second step of forming a plurality of through holes at predetermined positions in the green sheet having a front surface and a back surface, A mask is arranged on the green sheet with the groove facing upward, and at the time of the arrangement, a third step of arranging the through holes of the green sheet and the through holes of the mask in alignment with each other, and the third step on the mask. The filler is placed, and the squeegee is moved from the groove side toward the through-hole side of the mask on the mask to fill the groove with the filler, and the filler is transferred to the green sheet through the through-hole of the mask. A fourth step of filling the through holes.

  In the sixth aspect, the mask has a groove extending from the surface to the through hole on the surface of the mask, and the portion of the groove opening to the through hole is a mask facing a part of the inner peripheral surface of the through hole. Since it is used, the through holes of the green sheet can be sufficiently filled with a filler such as metallized ink.

  Specifically, by moving the filling material arranged on the mask with a squeegee, the filling material can be moved along the groove and reliably introduced into the through hole of the mask. Moreover, the filling material hits the inner peripheral surface of the through hole facing the groove and is sufficiently pushed into the through hole of the mask.

  Then, the filling material pushed into the through hole of the mask is further pushed into the through hole of the green sheet. As a result, the back surface of the green sheet (that is, the surface opposite to the mask) and its vicinity are sufficiently filled with the filler.

  As described above, in the sixth aspect, by using the mask having the above-described configuration, the filling material can be sufficiently filled in the through hole of the green sheet, particularly in the vicinity of the opening on the lower surface side of the through hole. When manufacturing the wiring board by firing the sheet, it is possible to suppress the occurrence of defects such as voids in a portion where the filling is insufficient (that is, the lower portion of the via).

  As a result, for example, when the conductive layer is formed so as to cover the surface of the via, it is possible to suppress the occurrence of irregularities in the conductive layer, and to sufficiently ensure conduction with other vias stacked with the via. Has a remarkable effect.

<Each configuration of the present invention will be described below>
As the mask, a metal mask made of metal can be mentioned, but in addition to this, masks made of various materials such as resin, ceramic, mask, etc. can be mentioned.

The shapes of the through holes of the mask and the through holes of the green sheet, for example, the cross-sectional shape when broken perpendicular to the thickness direction, may be various shapes such as a circle.
-The depth (maximum depth) of the groove may be in the range of 10 m to 40 m.

-The planar shape of the mask includes a range of □ 380 mm to □ 480 mm. The thickness of the mask may be in the range of 10 μm to 50 μm.
-The width of the groove (width in plan view seen from the thickness direction) may be in the range of 50 μm to 300 μm.

The width of the groove can be the same as the width of the through hole, but may be different depending on the distance to the through hole. For example, a fan-like shape whose width narrows toward the through hole can be used.
The green sheet is a known green sheet containing ceramic as a main component, or an unsintered sheet such as a green sheet containing ceramic and glass as a main component. As the material of the green sheet, well-known alumina, aluminum nitride, zirconia and the like can be mentioned.

  The squeegee is a member that moves the filler by its own movement, and examples thereof include a plate-shaped member made of metal, synthetic resin, or the like.

It is a top view which shows the metal mask of 1st Embodiment. (A) is a plan view showing the front surface of the metal mask, and (b) is a bottom view showing the back surface of the metal mask. FIG. 3 is a cross-sectional view (that is, an AA cross-sectional view of FIG. 2A) in which the metal mask is broken along the groove in the thickness direction. It is explanatory drawing which shows the method of filling a metallization ink using a metal mask. It is sectional drawing which fracture | ruptures and shows a part of ceramic wiring board in the thickness direction. (A) is sectional drawing which shows the green sheet with which the diameter of the opening part of the lower surface side became large, (b) is explanatory drawing which shows the method of opening a through hole in a green sheet. (A) is sectional drawing which fracture | ruptured the metal mask of 2nd Embodiment in the thickness direction, and shows the cross section of a through hole, a groove | channel, etc., (b) is a top view which shows the metal mask of 3rd Embodiment. It is explanatory drawing which shows the example of an experiment which investigated the filling state when using various masks. It is explanatory drawing which shows a prior art.

Next, an embodiment of the mask and wiring board manufacturing method of the present invention will be described.
[1. First Embodiment]
Here, a case will be described as an example where a metal mask is used to fill the through holes of the green sheet with metallized ink.
[1-1. Configuration of metal mask]
First, the metal mask of the first embodiment will be described.

As shown in FIG. 1, the metal mask 1 of the first embodiment is made of stainless steel, for example, and is a square plate material having a length of 380 mm × a width of 380 mm × a thickness of 0.03 mm.
The metal mask 1 is provided with a large number of through holes 3 (that is, mask through holes) 3 penetrating in the thickness direction. The arrangement of the through holes 3 is the same as the arrangement of the through holes (that is, the sheet through holes) 7 (see FIG. 4A) of the green sheet 5 which is a filling target (filled member) described later.

  As shown in an enlarged manner in FIG. 2, the through hole 3 of the metal mask 1 is a cylinder having a diameter of φ0.07 mm, for example. That is, as shown in FIG. 2A, the opening 3a on the front surface (upper surface) 11 side of the through hole 3 has a circular shape with the diameter in plan view, and as shown in FIG. The opening 3b on the back surface (lower surface) 13 side of 3 has a circular shape with the diameter in plan view.

  In particular, in the first embodiment, as shown in FIGS. 2A and 3, on the surface 11 of the metal mask 1, the groove 15 is formed from the groove start position MK apart from the through hole 3 to the through hole 3. Are formed. The groove start position MK is the position of the groove 15 farthest from the through hole 3 (the first position where the groove 15 deepens).

The groove 15 is formed so as to extend in a straight line (specifically, a band having a predetermined width) in one direction (left and right direction in FIG. 2A) with respect to the through hole 3.
That is, although the groove 15 is formed in each through hole 3, each groove 15 is provided on the same side (on the left side in FIG. 3) in each through hole 3, and moreover, in the extending direction of each groove 15. Are in the same direction (squeegeeing direction described below: X direction).

  The length S of the groove 15, that is, the distance S from the leftmost position (that is, the groove start position MK) in FIG. 2A to the leftmost position of the portion 17 opening in the through hole 3 is, for example, 0. It is 13 mm.

  The width W of the groove 15 is the same as the diameter of the through hole 3, for example, 0.07 mm. That is, the width (maximum width) of the portion 17 of the groove 15 that opens into the through hole 3 is equal to or smaller than the diameter (that is, the hole diameter) of the through hole 3 (here, the same as the diameter). Therefore, the tip of the opening 17 of the groove 15 reaches the upper end and the lower end of the through hole 3 in FIG. The planar shape of the groove on the left end side in FIG. 2A is, for example, a semicircle having a radius of 35 μm.

  Further, the portion 17 of the groove 15 that opens into the through hole 3 faces a part of the inner peripheral surface 19 of the through hole 3. That is, the inner peripheral surface 19 is formed on the right side of the groove 15 in FIG. 3 so as to sandwich the through hole 3 and be orthogonal to the direction in which the groove 15 extends (the left-right direction in FIG. 3).

  Further, the groove 15 has a bottom surface 21, and as a part of the bottom surface 21, the distance between the surface 11 and the bottom surface 21 increases toward the through hole 3 (that is, the groove 15 becomes deeper). ), The inclined surface 23 is inclined from the groove start position MK. Further, the bottom surface 21 has a flat surface 25 parallel to the surface 11 and extending from the end of the inclined surface 23 on the through hole 3 side to the through hole 3.

Here, the inclined surface 23 and the flat surface 25 may have any surface shape as long as they do not prevent the filling of the metallized ink 31 (see FIG. 4D). From the viewpoint of filling properties, it is preferable that the surfaces of the inclined surface 23 and the flat surface 25 have no unevenness. The inclination angle of the inclined surface 23 from the surface 11 is, for example, 45 ° in the range of 10 ° to 90 °. . Further, the depth T (see FIG. 3) from the surface 11 to the deepest portion of the groove 15 (that is, the flat surface 25) is in the range of 10 μm to 50 μm of the thickness of the metal mask 1 (here, 0.03 mm mentioned above). ), For example, 1/3. In other words, the depth T from the surface 11 to the flat surface 25 is, for example, 0.01 mm in the range of 10 μm to 40 μm.
[1-2. Wiring board manufacturing method]
Next, a method of manufacturing the wiring board of the first embodiment will be described.

<Preparation process>
First, as shown in FIG. 4A, a green sheet (ceramic green sheet) 5 containing ceramic or the like as a main component is produced by a known method.

  As the main component of the green sheet 5, various ceramics such as alumina, aluminum nitride, silicon nitride, glass ceramic, zirconium, and the like, and a mixture thereof can be used.

Then, as is well known, a binder and a solvent are added to these main components to prepare a slurry, and the green sheet 5 is prepared by, for example, a doctor blade.
The green sheet 5 is, for example, a sheet having a length of 200 mm × width of 200 mm × thickness of 30 μm or more and a rectangular shape in a plan view.

Then, through holes 7 are formed in the green sheet 5 at predetermined locations for forming vias by punching or the like.
Further, as shown in FIG. 4B, the metal mask 1 is manufactured.

Specifically, when the metal mask 1 is manufactured, first, the through hole 3 is formed at the same position as the through hole 7 of the green sheet 5 by a punch or the like on the plate material having the above-described size.
After that, a groove 15 is formed in the surface 11 of the metal mask 1 so as to reach the through hole 3 by, for example, a cutting process using laser etching. Instead of this method, the groove 15 may be formed by, for example, pressing.

-Further, a metallized ink 31 (see FIG. 4D), which is a filling material for forming vias, is prepared.
Well-known metallized ink 31 can be used. For example, a conductive material such as Mo, W, Ag, Ag / Pd, Ag / Pt, Au, and Cu, or a mixture thereof, which is made into a paste by adding a solvent or the like, can be used.

<Filling process>
Next, as shown in FIG. 4C, the green sheet 5 is placed on the base (stage) 33, and the metal mask 1 is placed on the green sheet 5 (with the groove 15 facing upward). To do.

At this time, the positions of the through holes 7 of the green sheet 5 and the through holes 3 of the metal mask 1 are aligned.
Next, as shown in FIG. 4D, the metallized ink 31 is placed on the surface 11 of the metal mask 1, and the squeegee 35 is moved along the surface of the metal mask 1. That is, the squeegee 35 is moved along the longitudinal direction of the groove (direction of arrow X).

  As a result, the metallized ink 31 moves along the inside of the groove 15 and its periphery, hits the inner peripheral surface 19 of the through hole 3 from the opening 17 of the groove 15, and moves in the arrow Y direction. As a result, the metallized ink 31 is pushed into the through hole 3 of the metal mask 1 and further pushed into the through hole 7 of the green sheet 5 to be filled.

<Post process>
Next, as shown in FIG. 4E, by removing the metal mask 1 from the surface of the green sheet 5, the green sheet 5 having the filling portion 37 filled with the metallized ink 31 in the through hole 7 is obtained. can get.

After that, as shown in FIG. 5, for example, a conductive paste serving as the conductive layer 43 is applied to the surface of the green sheet 5 so as to cover, for example, the filling portion 37 (which becomes the via 41), and then the plurality of green sheets 5 are formed. A ceramic wiring board 45 including the via 41, the conductive layer 43, and the like can be manufactured by stacking the above to manufacture a laminated body and firing as is well known.
[1-3. effect]
Next, the effect of the first embodiment will be described.

  In the first embodiment, the surface 11 of the metal mask 1 has the groove 15 extending from the surface 11 to the through hole 3, and the portion 17 of the groove 15 opening to the through hole 3 is the inner peripheral surface of the through hole 3. It faces a part of 19.

  In plan view, the groove 15 of the metal mask 1 is formed so as to extend in one direction with respect to the through hole 3, and the width of the portion 17 of the groove 15 that opens into the through hole 3 is the hole of the through hole 3. It is less than or equal to the diameter. Further, the bottom surface 21 of the groove 15 has an inclined surface 23 in which the distance between the surface 11 and the bottom surface 21 increases toward the through hole 3, and a flat surface 25 extending from the inclined surface 23 to the through hole 3.

Therefore, the metal mask 1 can be used to sufficiently fill the through holes 7 of the green sheet 5 with the metallized ink 31.
Specifically, by moving the metallized ink 31 with the squeegee 35, the metallized ink 31 is surely introduced into the through hole 3 of the metal mask 1 through the groove 15 and its vicinity, and at the same time, the through hole facing the groove 15 is formed. It hits the inner peripheral surface 19 of the metal mask 3 and is sufficiently pushed into the through hole 3 of the metal mask 1.

  Then, the metallized ink 31 pushed into the through holes 3 of the metal mask 1 is further pushed into the through holes 7 of the green sheet 5. As a result, the metallized ink 31 is sufficiently filled up to the lower surface of the green sheet 5 (that is, the surface opposite to the metal mask 1) and its vicinity.

  As described above, in the first embodiment, by using the metal mask 1 having the above-described configuration, the metallized ink 31 is applied to the inside of the through hole 7 of the green sheet 5, particularly near the opening 3b on the lower surface side of the through hole 7. Can be fully filled. Further, even when the moving speed of the squeegee 35 is increased to improve the process capability, or when the diameter of the through holes 7 (via diameter) is reduced to narrow the pitch, the metallized ink 31 is used as a green sheet. 5 can be sufficiently filled in the through hole 7, particularly in the vicinity of the opening 7a (see FIG. 4D) on the lower surface side of the through hole 7.

  Therefore, after that, when the green sheet 5 is fired to manufacture the ceramic wiring board 45, it is possible to suppress the occurrence of defects such as voids in a portion where the filling is insufficient (that is, the lower portion of the via 41).

  As a result, for example, when the conductive layer 43 is formed so as to cover the surface of the via 41, it is possible to prevent the conductive layer 43 from becoming uneven, and to sufficiently conduct the via 41 and other vias 41 to be stacked. It has a remarkable effect that it can be secured. Further, when the via is exposed on the surface of the wiring board, there is an advantage that unevenness on the board surface can be suppressed and smoothed.

Moreover, when the conductive layer 43 is formed on the surface of the ceramic wiring board 45 and the surface is plated, the unevenness of the surface is small, so that the plated layer can be formed appropriately.
Further, as shown in FIG. 6A, the through hole 7 of the green sheet 5 described above has a larger diameter due to the taper on the back surface side (the lower surface side in FIG. 6A) (that is, the through hole). 7 may spread), in which case it is difficult for the metallized ink 31 to reach the lower surface side. On the other hand, by using the metal mask 1 of the first embodiment, the metallized ink 31 can be sufficiently filled even on the lower surface side of the through hole 7 of the green sheet 5.

The reason why the lower surface side of the through hole 7 of the green sheet 5 is widened is schematically shown in FIG. 6B. The through hole 7 is formed in the green sheet 5 by using the mold 47 and the punch 49. This is because the upper end portion of the through hole 47a of the mold 47 is abraded during or after the die 47 is polished, and as a result, the lower end portion of the corresponding through hole 7 of the green sheet 5 is also widened. .
[1-4. Correspondence with Claims]
Here, the correspondence relationship of the wording between the embodiment and the claims will be described.

Through hole 3, metal mask 1, groove 15, opening portion 17, inner peripheral surface 19, bottom surface 21, inclined surface 23, flat surface 25, green sheet 5, through hole 7, squeegee 35 of the first embodiment. Each of the metallized inks 31 corresponds to an example of a through hole, a mask, a groove, an opening portion, an inner peripheral surface, a bottom surface, an inclined surface, a flat surface, a green sheet, a through hole, a squeegee, and a filler of the present invention.
[2. Second Embodiment]
Next, the metal mask of the second embodiment will be described, but the description of the same contents as those of the first embodiment will be omitted or simplified.

Note that the same numbers are used for the same configurations as in the first embodiment.
As shown in FIG. 7A, the metal mask 51 of the second embodiment has a through hole 3 penetrating in the thickness direction, and the surface 11 has a unidirectional (so as to reach the through hole 3) direction. A groove 53 extending in the left-right direction of 7 (a) is formed.

The bottom surface 55 of the groove 53 is an inclined surface in which the distance between the surface 11 and the bottom surface 55 increases toward the through hole 3.
The second embodiment also has substantially the same effects as the first embodiment.
[3. Third Embodiment]
Next, the metal mask of the third embodiment will be described, but the description of the same contents as those of the first embodiment will be omitted or simplified.

Note that the same numbers are used for the same configurations as in the first embodiment.
As shown in FIG. 7B, the metal mask 61 of the third embodiment has a through hole 3 penetrating in the thickness direction, and the surface 11 has a fan shape in plan view so as to reach the through hole 3. Groove 63 is formed. That is, the width of the groove 63 becomes narrower from the groove start position MK toward the through hole 3. That is, the groove 63 is formed so as to extend not only in one direction with respect to the through hole 3 but also in a direction perpendicular to the one direction. From the viewpoint of forming the through holes 7 at a narrow pitch, it is preferable that the grooves 15 be formed so as to extend in one direction with respect to the through holes 3 as in the first embodiment.

Further, the bottom surface 65 of the groove 63 is an inclined surface in which the distance between the surface 11 and the bottom surface 65 increases toward the through hole 3 as in the second embodiment.
Also in the third embodiment, substantially the same effect as that of the first embodiment is obtained.

[4. Fourth Embodiment]
Next, the metal mask of the fourth embodiment will be described, but the description of the same contents as those of the first embodiment will be omitted or simplified.

Although not shown here, the same configuration (configuration with the same name) as that of the first embodiment will be described using the same numbers.
The metal mask 1 of the fourth embodiment has a through hole 3 penetrating in the thickness direction, and a groove 15 extending in one direction is formed on the surface 11 so as to reach the through hole 3. The bottom surface 21 of the groove 15 is an inclined surface in which the distance between the surface 11 and the bottom surface 21 increases toward the through hole 3. This inclined surface is a combination of two inclined surfaces having different angles so as to be connected along the groove 15. Note that three or more inclined surfaces having different angles may be combined.

Also in the fourth embodiment, substantially the same effects as in the first embodiment are achieved.
[4. Experimental example]
Next, an experimental example conducted to confirm the effect of the present invention will be described.

  In this experimental example, No. 1 and 2 mask samples were prepared as samples of the Examples of the present invention, and No. 3 to 5 mask samples were prepared as Comparative Examples of samples outside the present invention. Then, the filling property was investigated. The material of the mask is acrylic here.

  Specifically, as shown in FIG. 8, a mask having the same shape as that of the first embodiment was prepared as a sample of No. 1 of the example, and a mask of No. 2 of the example was prepared as a second embodiment. A mask having the same shape as was manufactured.

  Similarly, as a sample No. 3 of the comparative example, a mask having no grooves and only through holes was prepared. Further, as a sample of No. 4 of the comparative example, a mask having a conical taper on the front side of the through hole was manufactured. Further, as a sample of No. 5 of the comparative example, a mask having a conical taper on the back side of the through hole was manufactured.

  Then, when the metallized ink was squeegeeed, it was examined how much the metallized ink protruded from the back side of the through hole of each mask. The squeegee speed was adjusted so that the metallized ink would not project excessively.

The results are also shown in FIG. 8, and it can be seen that the samples of Examples 1 and 2 have a large amount of protrusion of the metallized ink and have a high filling property.
On the other hand, the sample of the comparative example is not preferable because the amount of protrusion of the metallized ink is small and the filling property is low.
[5. Other Embodiments]
It is needless to say that the present invention is not limited to the above-described embodiment and can be carried out in various modes without departing from the present invention.

  (1) For example, the shape of the groove (for example, depth, length, width, or inclination angle of the inclined surface), the shape of the through hole of the metal mask, the shape of the through hole of the green sheet, and the configuration of the ceramic wiring board are the same as those described above. It is not limited to the form.

For example, the bottom surface of the groove may be formed such that the bottom surface is smoothly curved so that the distance between the surface and the bottom surface increases as it goes toward the through hole.
(2) Further, the materials for the metallized ink, the metal mask, and the green sheet are not limited to those in the above embodiment.

  (3) Further, the filling material is not limited to the metallized ink, and may be any material that can be filled using a mask. For example, various conductive inks and pastes can be used. In addition, non-conductive ink or paste may also be used.

  Further, the member to be filled with the filling material by the mask may be any member as long as it is filled by the mask, and is not limited to the green sheet, for example, various sheet-like or plate-like members having through holes, etc. Is mentioned.

  (4) The configurations of the above-described respective embodiments can be combined as appropriate.

1, 51, 61 ... Metal mask 3 ... Through hole 5 ... Green sheet 7 ... Through hole 15, 53, 63 ... Groove 17 ... Opening portion 19 ... Inner peripheral surface 21, 55, 65 ... Bottom surface 23 ... Inclined surface 25 ... Flat surface 31 ... Metallized ink 35 ... Squeegee

Claims (5)

In a mask having a front surface and a back surface, the through hole penetrating the front surface and the back surface,
On the surface of the mask, while having a groove from the surface to the through hole,
The portion of the groove that opens into the through hole faces a part of the inner peripheral surface of the through hole ,
The mask has a bottom surface, and has an inclined surface in which the distance between the surface and the bottom surface increases toward the through hole .   The mask according to claim 1, wherein the groove is formed so as to extend in one direction with respect to the through hole when seen in a plan view from the front surface side of the mask.   The mask according to claim 1 or 2, wherein a width of a portion of the groove that opens to the through hole is equal to or smaller than a hole diameter of the through hole in a plan view viewed from the front surface side of the mask. The bottom surface, which has the inclined surface, according to claim 1 to 3 wherein the leading surface and the end of the parallel and the through-hole side of the inclined surface in the through hole, and having a flat surface The mask according to any one of 1 . A first step of preparing the mask according to any one of claims 1 to 5 ;
A second step of forming a plurality of through holes at predetermined positions on the green sheet having a front surface and a back surface,
A third step of arranging the mask on the green sheet with the groove facing upward, and arranging the through holes of the green sheet and the through holes of the mask in alignment at the time of the arrangement. When,
A filler is arranged on the mask, a squeegee is moved on the mask from the groove side toward the through hole side of the mask to fill the groove with the filler, and the filler is A fourth step of filling the through holes of the green sheet through the through holes of the mask;
A method of manufacturing a wiring board, comprising: