JP2009253099A - Bottomed via filling substrate and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bottomed via filling substrate that is easily filled with a paste even when a via diameter is extremely small and a method of manufacturing the same. <P>SOLUTION: A mask opening 64 is elliptical with a minor axis equal to or less than the diameter of a bottomed via 56, and so the bottomed via 56 cannot be closed by conductor paste 58 when applying the conductor paste. Accordingly, the air in the bottomed via 56 is pushed out of the air gap between the mask opening 64 and the via 56 opening, so that void formation by the involved air in the bottomed via 56 is suppressed. In addition, an opening area of the mask opening 64 is equal to or larger than that of the bottomed via 56, and so more than half of the opening area of the bottomed via 56 is located in the mask opening 64. As a result, a sufficient amount of conductor paste 58 is supplied, and the amount of the paste 58 directly applied in the bottomed via 56 becomes sufficiently large, thereby the inside of the via bottomed 56 is easily filled with the conductor paste 58. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a bottomed via-filled substrate in which a bottomed via of a substrate is filled with a filling material and a method for manufacturing the same.

  For example, in an electronic circuit board, an insulator layer and a conductor wiring layer are alternately laminated to be multilayered for the purpose of reducing the size and weight. The insulator layer is provided with through conductors penetrating in the stacking direction at appropriate positions, and the conductor wiring layers provided above and below the insulator layer are electrically connected to each other by the through conductors.

The insulator layer is made of ceramics, glass, resin or the like. The conductor wiring layer includes a metal foil patterned by etching, a thick film conductor patterned by screen printing, a thin film conductor patterned by vapor deposition and etching, and the like. The conductor wiring layer is provided with a land larger than the area of the end face on the through conductor for interlayer connection. When forming the through conductor, for example, a via penetrating the insulator layer is provided, and a conductive paste is applied on the insulator layer by using, for example, a thick film screen printing method, and the via is filled. Curing is performed (see, for example, Patent Documents 1 to 3).
JP 09-036543 A JP 2000-307243 A JP 2002-118347 A

  By the way, the filling of the conductor paste for forming the through conductor may be performed for the through vias opened on both surfaces of the insulator layer or the bottomed via opened on only one surface. is there. In the former case, the conductor paste flows into the via without any interruption and is easily filled. If the conductor paste is difficult to flow in, such as when the via diameter is small, it may be sucked from the opening on the side opposite to the coating side as necessary. On the other hand, in the latter case, the air escape field in the via is only on the coating side, so if the applied conductor paste blocks the via opening, the air escape field is lost and replacement of the conductor paste with air is not possible. Become complete. Therefore, there is a problem that voids are formed by the entrained air and the electrical characteristics are impaired.

  On the other hand, a filling method has been proposed in which the mask opening diameter is made smaller than the via opening diameter so that a conductor paste is applied to the inner peripheral portion of the via and then flows toward the outer peripheral side (see above). (See Patent Documents 1 to 3). According to this filling method, since the conductor paste is supplied into the via with a gap remaining between the screen plate making and the substrate, the conductor paste can be easily filled in the via while extruding air from the gap. Can do.

  However, if the wiring width is reduced and the land size, via diameter, etc. are reduced for the purpose of further downsizing the electronic circuit board, new problems have arisen in the above-described techniques. In the screen printing method, paste is applied sequentially using multiple types of plate making, but the mask opening position for applying the conductor paste to the vias is shifted due to dimensional errors between the plate making and errors in the board placement position. There is a problem to get. In addition, misalignment due to displacement of the mask opening accompanying squeezing may occur. Therefore, it is necessary to determine the size and position of the mask opening in consideration of these deviations. Although it depends on the printing accuracy of the printing press, in general, considering that a deviation of about 100 to 200 (μm) is expected, for example, in a fine via having an opening diameter of about 150 (μm), the via In the case where the mask opening diameter is smaller than the diameter, the mask opening may be separated from the via due to the positional deviation, and the paste supply into the via becomes unstable.

  The present invention has been made against the background of the above circumstances, and an object of the present invention is to provide a bottomed via-filled substrate that can be easily filled with paste even when the via diameter is extremely small, and a method for manufacturing the same. .

  In order to achieve such an object, the gist of the first invention is a method of manufacturing a bottomed via-filled substrate by filling a plurality of bottomed vias opened on the substrate surface with a printing paste by screen printing. And (a) each of the plurality of bottomed vias filled with the printing paste has an opening area equal to or larger than an opening area of the corresponding bottomed via and has a bottomed via in a narrow width direction in a plan view. A mask printing plate having a plurality of mask openings having a flat shape having a delivery dimension equal to or less than a delivery dimension of the plurality of bottomed vias, wherein 45% or more of the opening area of each of the plurality of bottomed vias is the mask opening. The purpose is to perform screen printing by placing it in the department.

  The gist of the second invention is a bottomed via-filled substrate in which each of a plurality of bottomed vias opening on the substrate surface is filled with a predetermined filling material, and (a) the plurality of bottomed vias Each of the plurality of application regions where the filling material is applied to each of the vias has an area that is equal to or larger than the opening area of each of the plurality of bottomed vias, and each of the widthwise dimensions in the plan view is Each of the plurality of bottomed vias has a flat shape that is equal to or smaller than the passing dimension in the direction, and 45 (%) or more of the opening area of each of the plurality of bottomed vias is located in the plurality of application regions. There is.

  According to the first aspect of the present invention, screen printing for filling a plurality of bottomed vias with a printing paste is performed using a screen printing plate making machine having a plurality of mask openings. The bottomed via has a flat shape whose width dimension in the narrow width direction is less than or equal to the bottomed via dimension, so that when the printing paste is applied, the bottomed via is blocked with the printing paste. Is suppressed. Therefore, when the printing paste flows into the bottomed via and is filled and filled, the air in the bottomed via is pushed out from the gap between the mask opening and the via opening. Is prevented from forming a void. Moreover, since the opening area of the mask opening is larger than the opening area of the bottomed via, and 45% or more of the opening area of the bottomed via is located in the mask opening, the bottomed via In contrast, since a sufficient amount of printing paste is supplied and the amount of printing paste applied directly into the bottomed via becomes sufficiently large, the bottomed via is easily filled with the printing paste. Therefore, according to the manufacturing method of the bottomed via-filled substrate of the first invention, paste filling can be easily performed even when the via diameter is extremely small.

  According to the second aspect of the present invention, the application region of the filling material has a flat shape in which the passing dimension in the narrow width direction is equal to or smaller than the passing dimension of the bottomed via, and the area is equal to or larger than the opening area of the bottomed via, Since 45 (%) or more of the opening area of the bottomed via is located in the coating region, this bottomed via-filled substrate can be easily manufactured by applying the manufacturing method of the first invention. That is, paste filling can be easily performed even when the via diameter is very small, and a bottomed via-filled substrate in which the inside of the bottomed via is filled with a filling material without generating voids can be obtained.

  If the passing dimension in the narrow width direction of the mask opening is larger than the passing dimension of the bottomed via, the bottomed via opening is blocked by the printing paste supplied from the mask opening when the printing paste is applied. There is a problem that voids may occur due to air entrainment. If a part of the bottomed via opening is located at a position away from the mask opening, the above problem is unlikely to occur. If it is larger than the passing dimension of the bottomed via, there is a possibility that the bottomed via opening is blocked due to dimensional accuracy at the time of manufacture, misalignment, or the like.

  Also, if 45% or more of the opening area of the bottomed via is not located in the mask opening, the area where the printing paste is directly supplied becomes too small, so the position of the bottomed via opening that is out of the mask opening. The supply of the printing paste to the portion in the region becomes unstable, and as a result, filling failure may occur.

  Here, in the first invention, preferably, each of the plurality of mask openings has the narrow width direction perpendicular to the squeezing direction. The mask opening is displaced in the squeezing direction exclusively during printing, but the mask opening has a flat shape that is long in the squeezing direction, so that even when displaced, the mask opening is unlikely to come off from the bottomed via opening. Become. Therefore, it is easy to ensure that the area to which the printing paste is directly supplied is 45 (%) of the bottomed via opening area.

  Preferably, each of the plurality of mask openings has an elliptical shape. In this way, even if printing position misalignment or the like occurs, the area of the bottomed via located in the mask opening is unlikely to change, so the area where the printing paste is directly supplied is equal to the bottomed via opening area. It becomes easy to ensure it to be 45 (%).

  Preferably, the width dimension of each of the plurality of mask openings is not less than 2/3 of the width dimension of each of the plurality of bottomed vias in that direction. In this way, since the width of the mask opening in the narrow width direction is sufficiently large, it becomes easier to supply the printing paste.

  Preferably, each of the plurality of mask openings is provided at a position shifted in a direction crossing the squeezing direction with respect to each of the plurality of bottomed vias. In this way, even if the mask opening is displaced in the squeezing direction during printing, the ratio of the bottomed via opening area located within the mask opening is unlikely to change, and thus more stable printing is possible. .

  In the second invention, preferably, each of the plurality of application regions has an elliptical shape. Since such a coating area is formed by using a screen printing plate making having an elliptical mask opening, the area to which the printing paste is directly supplied changes due to misalignment during printing and fills The material is preferably prevented from filling the bottomed via.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In the following embodiments, the drawings are appropriately simplified or modified, and the dimensional ratios, shapes, and the like of the respective parts are not necessarily drawn accurately.

  FIG. 1 is a view showing a cross section of a main part of a multilayer circuit board 10 which is an embodiment of a bottomed via-filled board of the present invention. In FIG. 1, a multilayer circuit board 10 has, for example, a total thickness of about 1.2 (mm), and a first conductor wiring layer 14, a first insulator layer 16, and a second conductor wiring are formed on a base substrate 12. The layer 18, the second insulator layer 20, the third conductor wiring layer 22, the third insulator layer 24, the fourth conductor wiring layer 26, the fourth insulator layer 28, the fifth conductor wiring layer 30, and the plating layer 32 are sequentially formed. Is laminated. Each insulator layer 16, 20, 24, 28 is provided with vias 34, 36, 38, 40 penetrating in the thickness direction, and via conductors 42, 36, 38, 40 are respectively provided in the vias 34, 36, 38, 40. 44, 46 and 48 are filled.

  The base substrate 12 is made of alumina having a thickness dimension of about 0.8 (mm), for example. The first conductor wiring layer 14 is made of thick film copper having a thickness dimension of about 20 (μm), for example, and a thick film copper paste is screened on the base substrate 12 in a predetermined wiring pattern. It is formed by printing.

  The second conductor wiring layer 18 to the fifth conductor wiring layer 30 are all made of copper foil, but the wiring layers 18, 22, and 26 have a thickness dimension of about 12 (μm), for example. The wiring layer 30 has a thickness dimension of about 35 (μm), for example. These wiring layers 18, 22, 26, 30 all have different wiring pattern shapes formed by, for example, etching.

  The plating layer 32 is made of, for example, nickel, and the fifth conductor wiring is used for soldering external wiring or components to the fifth conductor wiring layer 30 formed on the uppermost layer of the multilayer circuit board 10. The layer 30 is provided in the same shape. That is, since the fifth conductor wiring layer 30 made of copper foil is inferior in solderability, the plating layer 32 improves this.

  Each of the via conductors 42 to 48 is made of a thick film conductor material containing, for example, an Ag / Sn alloy as a conductor component, and is closely filled in the vias 34 to 40. The layers of the conductor wiring layers 14 to 30 are electrically connected to each other by via conductors 42 to 48. 1 shows that the vias 34 to 40 are provided at the same position in the plane direction of the insulator layers 16 to 28, but the connection between the layers is formed in each of the conductor wiring layers 14 to 30. The multilayer circuit board 10 is provided with a portion where only some of the conductor wiring layers 14 to 30 are connected to each other as necessary. Yes.

  In the multilayer circuit board 10, for example, the conductor wiring layers 18 to 30 and the insulator layers 16 to 28 are each one layer, that is, the first insulator layer 16, the second conductor wiring layer 18, and the second insulation. The conductor layer-insulator layer in which the body layer 20 and the third conductor wiring layer 22, the third insulator layer 24 and the fourth conductor wiring layer 26, and the fourth insulator layer 28 and the fifth conductor wiring layer 30 are laminated. A laminate 68 (see FIG. 2) is prepared, and the laminate is manufactured by superposing them on the base substrate 12 on which the first conductor wiring layer 14 is formed, and performing hot pressing. Among the above, the manufacturing method of the conductor layer-insulator layer laminate 68 will be described below with reference to FIG.

  In FIG. 2A, first, a Cu adhesive film 54 in which a resin film 52 is provided on an electrolytic Cu foil 50 is prepared. The resin coating 52 is made of, for example, a thermoplastic resin, and the Cu adhesive film 54 is manufactured, for example, by applying a resin solution to the Cu foil 50 and curing it.

  Next, in the etching step shown in FIG. 2B, the Cu foil 50 is subjected to an etching process in a predetermined wiring shape to form a pattern. Next, in the dividing step shown in FIG. 2 (c), this is divided into a size that can be easily handled in a subsequent step by using an appropriate method such as punching. 2D, a bottomed via 56 is provided at an appropriate position of the resin film 52 of the divided base material. Although this drilling process will not be specifically limited if it is a method which can process the resin film 52 selectively, For example, it can perform using a carbon dioxide laser etc. The dividing step is to divide into small pieces so that an inexpensive carbon dioxide laser can be used in this step.

  Next, in the paste filling step shown in FIG. 2E, the bottomed via 56 is filled with the conductive paste 58 by using, for example, a thick film screen printing method. FIG. 3 is an enlarged view of FIG. 2 (e) showing the filling process of the conductive paste 58, and shows a stage slightly advanced from FIG. 2 (e). On the Cu adhesive film 54, a screen printing plate making 60 is arranged, and the squeegee 62 is fed in the right direction in the drawing as indicated by an arrow, so that the conductive paste 58 on the plate making 60 becomes a mask opening 64 of the plate making 60. And is applied in the bottomed via 56. The plate making 60 is, for example, a metal mask formed by patterning a thin metal plate by etching or the like.

  At this time, the mask opening 64 of the plate making 60 and the bottomed via 56 of the Cu-attached film 54 are in the positional relationship shown in FIG. 4, for example. The bottomed via 56 is, for example, circular, and has a diameter of, for example, about φ150 (μm). The bottomed via 56 is located on the back side of the coated surface, that is, in the center of the land 66 provided on the Cu foil 50. The land 66 has a circular shape of about φ400 (μm), for example.

  On the other hand, the mask opening 64 has an elliptical shape in which, for example, the squeezing direction indicated by the arrow S coincides with the major axis direction. For example, the major axis is about 200 to 350 (μm) and the minor axis is about 150 (μm). Is equipped. That is, the mask opening 64 is provided with the same short diameter as the opening diameter of the bottomed via 56, and a longer diameter larger than that of the bottomed via 56. The opening area is, for example, twice that of the bottomed via 56. Degree. The mask opening 64 has a center Co shifted from the center Cv of the bottomed via 56 in a squeezing direction (hereinafter referred to as Y direction as appropriate) and a direction perpendicular thereto (hereinafter referred to as X direction as appropriate). In the illustrated example, the left half of the opening of the bottomed via 56 is located within the mask opening 64, and the right half of the opening is located away from the mask opening 64. It is in. The amount of displacement of the mask opening 64 is, for example, about 50 (μm) in both the X direction and the Y direction.

  As described above, since the mask opening 64 is provided at a position shifted from the bottomed via 56, when screen printing is performed as described above, as shown in FIG. The conductor paste 58 flows from a part of the opening of the bottomed via 56 and flows in the bottomed via 56. That is, the conductor paste 58 flows as indicated by the arrow P and fills the bottomed via 56. FIG. 3 is a schematic diagram for explaining the flow of the conductor paste 58, and does not exactly correspond to the positional relationship between the bottomed via 56 and the mask opening 64 as shown in FIG. As shown in FIG. 4, in a mode in which the major axis direction of the mask opening 64 coincides with the squeezing direction and is shifted in the X direction and the Y direction with respect to the bottomed via 56, it is transverse to the squeezing direction. The conductor paste 58 flows into the bottomed via 56 from a part of the direction. Therefore, FIG. 4 corresponds to FIG. 4 in which the squeezing direction is changed by 90 degrees to make the direction perpendicular to the paper surface.

  FIG. 5 is a perspective view showing the state when the conductive paste 58 is filled, omitting the plate making 60 and the like. The downward arrow indicates the flow of the conductive paste 58, and the upward arrow indicates the flow of air. Yes. When the conductive paste 58 is applied and filled, the conductive paste 58 flows from a part of the opening of the bottomed via 56 and spreads in the bottomed via 56 as described above. At this time, air is sent out from the bottomed via 56 in accordance with the flow of the conductor paste 58. That is, when the conductive paste 58 is applied, the portion of the opening of the bottomed via 56 that is located in the mask opening 64 is blocked by the conductive paste 58, but the portion that is located away from the mask opening 64. Since the air gap is left between the resin film 52 and the plate making 60 in (the front right side portion in FIG. 5), air escapes from the gap, so that air is not caught in the bottomed via 56. . Since the plate-making 60 is pressed against the printing surface during squeezing, the opening of the bottomed via 56 is closed, but also at that time, a gap is generated between the plate-making 60 made of a metal mask and the printing surface. If it is not blocked by the conductive paste 58, an air escape path is left.

  For this reason, the mask opening 64 is made larger than the opening of the bottomed via 56, so that a sufficient amount of paste can be ensured, and the void is not generated in the bottomed via 56. Paste 58 is filled. In FIG. 5, 70 represents a range where the conductor paste 58 is applied, and coincides with the mask opening 64. In FIG. 3 as well, the upward arrow represents the flow of air discharged from the bottomed via 56.

  FIG. 2 (f) shows a conductor layer-insulator layer laminate 68 obtained by filling the conductor paste 58 as described above. As described above, the conductive paste 58 is applied from the large mask opening 64 to the bottomed via 56, so that the coating range covers a wider range than the bottomed via 56 as shown in the figure. Yes. As apparent from the above description, this coating range substantially matches the range indicated by the mask opening 64 in FIG.

  Thus, after manufacturing the conductor layer-insulator layer laminated body 68 for constituting each layer, the multilayer circuit board 10 is obtained by superposing and hot pressing as described above. Therefore, in the multilayer circuit board 10 obtained through such a manufacturing process, the application region of the via conductors 42 to 48 substantially matches the range of the mask opening 64 shown in FIG. Is the same as the diameter of the bottomed via 56 and has an elliptical shape with an area larger than the opening area of the bottomed via 56, and a little more than half of the opening area of the bottomed via 56 is located in the coating region It has become.

  FIG. 6 shows the ratio of the opening area of the bottomed via 56 in the mask opening 64 in the paste filling step (that is, the ratio of the paste passage area to the via area; hereinafter referred to as the effective area ratio). The results of evaluating the relationship between the ratio of the number of vias that can be completely filled with respect to the total number of vias in the substrate (hereinafter referred to as the non-defective product ratio) are summarized, and the solid line indicates that the minor axis of the mask opening 64 is 150 ( In the case of μm), the broken line indicates the case of 100 (μm). The opening diameters of the bottomed vias 56 are all 150 (μm), the major diameter of the mask opening 64 is changed between 200 to 350 (μm), and the positional deviation amount (distance between Cv and Co in FIG. 4) is changed. The effective area ratio was changed by changing. In addition, the above “filled” means that the conductor could be completely filled in the bottomed via 56 without causing a void due to air entrainment.

  According to the above evaluation results, when the short diameter is 150 (μm), the effective area ratio is about 30% or less, and when the short diameter is 100 (μm), the effective area ratio is 40 (%). The ratio of non-defective products will be approximately 0 (%) when the ratio is less than about, but the number of vias that can be filled will increase when this ratio is exceeded. In the case of a diameter of 100 (μm), the non-defective rate was 100 (%) when the diameter was about 45 (%) or more. There was no particular difference in tendency due to the difference in major axis. According to this result, by defining the positional relationship between the bottomed via 56 and the mask opening 64 so that the effective area ratio is 45 (%) or more, the conductor paste 58 is reliably filled in the bottomed via 56. It became clear that we could do it.

  When the effective area ratio is 100 (%), the opening of the bottomed via 56 is completely blocked by the conductive paste 58 during application, so there is no air escape path and filling is difficult. Is predicted. Moreover, even if it is not completely blocked, if the air escape path becomes small, it is predicted that filling will be difficult. However, as a result of the actual test, as shown in FIG. 6, even when the effective area ratio was increased to 100 (%), there was no tendency for the yield rate to decrease. That is, although the reason is not clear, if the short diameter is equal to or smaller than the diameter of the bottomed via 56, even if the effective area ratio is 100 (%), the filling failure of the conductor paste 58 does not occur. .

  Further, the above evaluation is for the case where the major axis direction of the mask opening 64 is the direction (longitudinal direction) coinciding with the squeezing direction. There is no change in the effect of securing the air escape path in the bottomed via 56 during filling. Therefore, for example, the mask opening is provided in a direction (lateral direction) in which the minor axis direction coincides with the squeezing direction, or an intermediate direction thereof (that is, an oblique direction inclined by, for example, 45 degrees with respect to the squeezing direction). You can also However, when these were evaluated, the non-defective product rate was 100 (%) when the effective area rate was 50 (%) or more in the horizontal direction and 62 (%) or more in the diagonal direction. Therefore, it is considered most preferable to provide the mask opening 64 in the vertical direction from the viewpoint of process stability.

  As described above, according to the present embodiment, when the screen printing for filling the bottomed via 56 with the conductor paste 58 is performed, the mask opening 64 has a short diameter dimension with respect to the bottomed via 56. Since the bottomed via 56 has an elliptical shape having a diameter equal to or smaller than that of the bottomed via 56, the bottomed via 56 is not blocked by the conductive paste 58 when the conductive paste 58 is applied. Therefore, when the conductor paste 58 flows into the bottomed via 56 and spreads and is filled, the air in the bottomed via 56 is pushed out from the gap between the mask opening 64 and the via 56 opening. It is suppressed that air is caught in the bottom via 56 to form a void. In addition, since the opening area of the mask opening 64 is larger than the opening area of the bottomed via 56 and more than half of the opening area of the bottomed via 56 is located in the mask opening 64, A sufficient amount of the conductive paste 58 is supplied to the bottom via 56 and the amount of the conductive paste 58 applied directly into the bottomed via 56 is sufficiently large. Easily filled with 58.

  In the above-described embodiment, the case where the center Co of the mask opening 64 is shifted from the center Cv of the bottomed via 56 opening has been described. However, it is essential that the positional relationship be shifted in this way. is not. As described above, even if the effective area ratio is 100 (%), any positional relationship can be used as long as the minor axis dimension of the mask opening 64 is equal to or smaller than the diameter of the bottomed via 56. There is no filling failure caused by completely closing the opening of the bottomed via 56. Therefore, in order to avoid that the effective area ratio is reduced to less than 45 (%) due to an alignment error at the time of printing, a manufacturing error of the plate making 60, and the like, resulting in poor filling, the center Co, It is also a preferred embodiment that the Cv is designed to match.

  As mentioned above, although this invention was demonstrated in detail with reference to drawings, this invention can be implemented also in another aspect, A various change can be added in the range which does not deviate from the main point.

It is a schematic diagram which shows the principal part of the cross-sectional structure of the bottomed via filling board | substrate of one Example of this invention. It is a figure which shows typically each step of the process for demonstrating the manufacturing method of the conductor layer-insulator layer laminated body for manufacturing the bottomed via filling board | substrate of FIG. It is a schematic diagram for demonstrating the paste filling process of FIG. It is a top view which shows the positional relationship of a bottomed via and the opening part of screen plate-making. It is a perspective view for demonstrating the motion of the conductor paste in FIG. It is the graph which put together the relationship between the ratio of the paste passage area with respect to a via area, and a non-defective rate.

Explanation of symbols

10: Multilayer circuit board, 12: Base substrate, 14: First conductor wiring layer, 16: First insulator layer, 18: Second conductor layer, 20: Second insulator layer, 22: Third conductor layer , 24: third insulator layer, 26: fourth conductor wiring layer, 28: fourth insulator layer, 30: fifth conductor wiring layer, 32: plated layer, 34, 36, 38, 40: via, 42, 44, 46, 48: Via conductor, 50: Cu foil, 52: Resin film, 54: Cu adhesive film, 56: Bottom via, 58: Conductor paste, 60: Plate making for screen printing, 62: Squeegee, 64: Mask Opening, 66: Land, 68: Conductor layer-insulator layer laminate

Claims (7)

A method of manufacturing a bottomed via-filled substrate by filling each of a plurality of bottomed vias opened on a substrate surface with a printing paste by screen printing,
Each of the plurality of bottomed vias filled with the printing paste has an opening area that is equal to or larger than the opening area of the corresponding bottomed via, and is less than the dimension of the bottomed via in the narrow width direction in plan view A screen printing plate having a plurality of mask openings having a flat shape having dimensions, and a screen in which 45% or more of the opening area of each of the plurality of bottomed vias is positioned in the mask openings. A method of manufacturing a bottomed via-filled substrate, wherein printing is performed.   2. The method of manufacturing a bottomed via-filled substrate according to claim 1, wherein each of the plurality of mask openings has the narrow width direction perpendicular to the squeezing direction.   3. The method for manufacturing a bottomed via-filled substrate according to claim 1, wherein each of the plurality of mask openings has an elliptical shape.   4. The width of each of the plurality of mask openings in the narrow direction is not less than 2/3 of the width of each of the plurality of bottomed vias in that direction. 5. A method for producing a bottomed via-filled substrate according to claim 1.   5. The device according to claim 1, wherein each of the plurality of mask openings is provided at a position shifted in a direction intersecting the squeezing direction with respect to each of the plurality of bottomed vias. A method for producing a bottomed via-filled substrate according to Item. A bottomed via-filled substrate in which each of a plurality of bottomed vias opening on the substrate surface is filled with a predetermined filling material,
Each of the plurality of application regions where the filling material is applied to each of the plurality of bottomed vias has an area larger than the opening area of each of the plurality of bottomed vias, and each narrow width in plan view Each of the plurality of bottomed vias has a flat shape having a dimension equal to or less than that of each of the plurality of bottomed vias, and 45 (%) or more of the opening area of each of the plurality of bottomed vias is the plurality of coatings. A bottomed via filled substrate, characterized in that it is located in a region.   The bottomed via-filled substrate according to claim 6, wherein each of the plurality of application regions has an elliptical shape.

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