JPH08228075A - Manufacture of substrate - Google Patents

Abstract

PURPOSE: To make each conductive pattern of the top face and underside of a substrate have a sure continuity with high reliability, and to connect the substrate to another mounting substrate without generating defective connection. CONSTITUTION: A through-hole 4 communicating with an underside from a top face is formed, the underside opening section 5 of the through-hole 4 is closed by a receiving member 6, flux 8 is injected from the top-face opening section 7 of the through-hole 4, solder powder 9 is injected from the top-face opening section 7, and flux 8 and powder solder 9 are made to reflow in the manufacture of a substrate. Spherical solder is loaded in the top-face opening section 7 after the injection process of powder solder 9, and flux 8, powder solder 9 and spherical solder are made to reflow in the manufacture of the substrate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a semiconductor device substrate.

[0002]

2. Description of the Related Art Conventionally, there is a substrate, for example, a printed circuit board, in which conductive patterns formed on the upper surface and the lower surface of an insulating substrate material are electrically connected through through holes. Further, as an attempt to increase the density, increase the number of pins, and improve the mountability of a semiconductor device, there is a semiconductor element mounting substrate having conductive patterns formed on the upper and lower surfaces.

Conduction between the conductive patterns on the upper surface and the lower surface of these substrates is carried out by plating copper on the inner peripheral surfaces of the through holes communicating with the conductive patterns, or by plating with copper and then solder plating.

[0004]

In the conduction of the substrate, since the substrate material to be plated is insulative, the adhesion is poor and the plating may be peeled off, resulting in a decrease in reliability.
In particular, when the substrate material is a semiconductor element mounting substrate such as a polymide tape, the plating peeling occurs frequently, which is a problem.

In order to prevent the peeling of the plating, a complicated and multi-step pretreatment is required prior to the plating on the inner peripheral surface of the through hole, which causes a problem in workability and productivity, and also causes an increase in cost. .

The board having conductive patterns formed on the upper and lower surfaces is connected to wiring terminals of another mounting board and assembled. For the connection, solder balls are provided on the through holes on the mounting surface side of the board for the connection, and the solder balls are heated to melt and connect to the wiring terminals. The solder balls may flow into the hollow portion, which may result in defective height of the solder balls or defective connection between the substrate and the mounting substrate.

Further, since the solder ball has a small contact area with the substrate and has a low adhesive strength, the solder ball may be removed from the substrate.

It is an object of the present invention to provide a method of manufacturing a substrate in which the conductive patterns formed on the upper surface and the lower surface are surely highly conductive, and can be connected to another mounting board without causing a connection failure.

[0009]

SUMMARY OF THE INVENTION The gist of the present invention is to provide a through hole communicating from the upper surface to the lower surface and to fill the through hole with a conductive substance. A flux injecting step of injecting a flux that improves solder wettability into the through hole by closing one of the surfaces, and a solder powder filling step of filling the through hole into which the flux is injected with powdered solder. , A method of manufacturing a substrate through a reflow step of heating flux and powdered solder.

Another aspect is that in a method of manufacturing a substrate in which a through hole communicating from the upper surface to the lower surface is provided and a conductive substance is filled in the through hole, either one of the upper surface and the lower surface is provided. A flux injection step of injecting a flux that closes the through hole to improve solder wettability, a solder powder filling step of filling the through hole into which the flux is injected with a powdered solder, and a non-closed surface It is a method of manufacturing a substrate that includes a step of mounting spherical solder in a through hole and a reflow step of heating flux and powdery solder.

[0011]

In the substrate manufacturing method of the present invention, since the flux and the solder powder are filled in the through holes and the reflow is performed, it is possible to suppress the decrease in the volume of the filling material and prevent the generation of voids. Is surely reliable.

Furthermore, a solder ball having a stable height can be surely mounted on one of the upper surface and the lower surface of the through hole, and conduction with another mounting board can be surely made highly reliable.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for manufacturing a substrate used for mounting a semiconductor device according to the present invention will be described in detail with reference to the drawings.

First, in the first embodiment, as shown in FIG. 1, the upper surface conductive pattern 2 and the lower surface conductive pattern 3 are formed on the upper surface and the lower surface of the base material 1 by etching, and the through holes 4 are formed by etching. 2 and the lower surface conductive pattern 3 are formed, the lower surface opening 5 of the through hole 4 is closed by the receiving member 6, the flux 8 is injected through the upper surface opening 7 of the through hole 4, and further through the upper surface opening 7. By injecting the solder powder 9 to fill the upper surface of the through hole 4 and directly or indirectly heating the receiving member 6 to reflow the flux 8 and the solder powder 9, the receiving member 6 is removed, and a substrate is manufactured. is there.

In the second embodiment, as shown in FIG.
Upper surface conductive pattern 2 and lower surface conductive pattern 3 are formed on the upper surface and lower surface of the through hole 4, and through hole 4 is formed by etching so as to communicate with upper surface conductive pattern 2 and lower surface conductive pattern 3, and upper surface opening 7 of through hole 4 is formed. A solder resist 10 is formed on the through hole 4, a lower surface opening 5 of the through hole 4 is closed by a receiving member 6, a flux 8 is injected from an upper surface opening 7 of the through hole 4, and a solder powder 9 is further injected from an upper surface opening 7. The upper surface opening 7 of the through hole 4 is filled with the spherical solder 11 and the receiving member 6 is directly or indirectly heated to heat the flux 8 and the solder powder 9 and the spherical solder 10. Is reflowed, the receiving member 6 is removed, and a substrate is manufactured.

In the third embodiment, as shown in FIG.
Upper surface conductive patterns 2 and lower surface conductive patterns 3 are formed on the upper and lower surfaces of the through holes 4, and through holes 4 are formed by etching so as to communicate with the upper surface conductive patterns 2 and the lower surface conductive patterns 3. A solder resist 10 is formed on the through hole 4, a lower surface opening 5 of the through hole 4 is closed by a receiving member 6, a flux 8 is injected from an upper surface opening 7 of the through hole 4, and a solder powder 9 is further injected from an upper surface opening 7. Then, the upper surface of the through hole 4 is filled up, the receiving member 6 is directly or indirectly heated to reflow the flux 8 and the solder powder 9, and the spherical solder 11 is mounted on the reflowed filled solder 12. In this method, the filling solder 12 and the spherical solder 11 are reflowed, the receiving member 6 is removed, and a substrate is manufactured.

According to this manufacturing method, when the solder powder 9 is filled, the solder powder 9 can be raised higher than the upper surface opening portion 7, and the filled solder 12 can be formed higher in the upper surface direction, so that the solder ball portion can be formed. The height of 13 can be increased, and the connection with other mounting boards is further ensured.

In the fourth embodiment, as shown in FIG. 4, an upper surface conductive pattern 2 and a lower surface conductive pattern 3 are formed on the upper surface and the lower surface of a base material 1 by etching, and the through holes 4 are formed by etching. And the lower surface conductive pattern 3, and a solder resist 10 is formed in the upper surface opening 7 of the through hole 4, the lower surface opening 5 of the through hole 4 is closed by the receiving member 6, and the upper surface opening 7 is soldered. The powder holding jig 14 is mounted, the flux 8 is injected from the upper surface opening 15 of the solder powder holding jig 14, and the solder powder 9 is further filled up to above the upper surface of the solder powder holding jig 14. The flux 8 and the solder powder 9 are reflowed by directly or indirectly heating the receiving member 6, and the solder holding jig 14 is removed at the stage when the solder powder 9 is melted during the reflow. Remove a method of manufacturing a substrate, characterized in that the receiving member 6 removed.

According to this method, the spherical solder 11 is not required, the process can be simplified, and the height of the solder ball 13 can be increased, so that the connection with another mounting substrate can be made more reliable. Become.

In the second, third and fourth embodiments, the upper conductive pattern 2 and the lower conductive pattern 3 are formed on the upper surface and the lower surface, respectively, but this is optional. As shown in FIG. 5, the conductive pattern is formed on the upper surface. It is also possible to form only the solder ball portion 13 that conducts with another mounting board without forming the solder ball portion.

In the embodiment described above, the receiving member 6
The bottom opening 5 is covered with and the flux 8 and the solder powder 9 or the flux 8 and the solder powder 9 and the spherical solder 11 are reflowed by directly or indirectly heating the receiving member 6, but this is optional. As shown in FIG. 6, a lower surface conductive pattern 16 is formed so as to cover the through holes 4, and the lower surface conductive pattern 16 is directly or indirectly heated to form the flux 8 and the solder powder 9 or the flux 8 and the solder powder 9. The spherical solder 11 may be reflowed.

According to this method, the steps of attaching and detaching the receiving member 6 can be omitted and the manufacturing process can be simplified.

Further, by filling the flux 8 and the solder powder 9 while performing reflow from the lower surface in the above-described embodiment, the generation of voids can be further prevented, and the conduction between the upper surface and the lower surface is further ensured. .

[0024]

According to the board manufacturing method of the present invention, since the solder powder and the flux are used as described above, the volume reduction in the reflow step is small, and the through holes are sufficiently filled with solder. Therefore, it is possible to prevent conduction defects of the conductive patterns provided on the upper surface and the lower surface of the substrate, and it is possible to significantly improve the manufacturing yield.

Furthermore, since solder balls having a stable height can be formed on one of the upper surface and the lower surface of the through hole, connection can be made to other mounting boards without causing connection failure.

[0026]

[Brief description of drawings]

FIG. 1 is a diagram for explaining a first embodiment of a substrate manufacturing method according to the present invention.

FIG. 2 is a diagram for explaining a second embodiment of the method of manufacturing a substrate according to the present invention.

FIG. 3 is a drawing for explaining the third embodiment of the method for manufacturing a substrate according to the present invention.

FIG. 4 is a drawing for explaining the fourth embodiment of the method of manufacturing a substrate according to the present invention.

FIG. 5 is a drawing for explaining a part of the embodiment of the method for manufacturing a substrate according to the present invention.

FIG. 6 is a view for explaining a part of the embodiment of the method for manufacturing the substrate according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base material 2 Upper surface conductive pattern 3 Lower surface conductive pattern 4 Through hole 5 Lower surface opening 6 Receiving member 7 Upper surface opening 8 Flux 9 Solder powder 10 Solder resist 11 Spherical solder 12 Filled solder 13 Solder ball part 14 Solder powder holding jig 15 Upper surface opening 16 Lower surface conductive pattern

Claims (2)

[Claims] 1. A method of manufacturing a substrate in which a through hole communicating from the upper surface to the lower surface is provided, and the through hole is filled with a conductive material, wherein either one of the upper surface and the lower surface is closed and the through hole is closed. Substrate obtained through a flux injecting step of injecting a flux into the through hole, a solder powder filling step of filling the through hole into which the flux is injected with a powdery solder, and a reflow step of heating the flux and the powdery solder. Manufacturing method. 2. A method of manufacturing a substrate in which a through hole communicating from the upper surface to the lower surface is provided, and the through hole is filled with a conductive substance, wherein either one of the upper surface and the lower surface is closed. Flux injection step of injecting flux into the through hole, solder powder filling step of filling the through hole into which the flux is injected with powdered solder, and step of mounting spherical solder in the through hole of the surface not blocked and flux And a method of manufacturing a substrate that undergoes a reflow step of heating powdered solder and spherical solder.