Method for manufacturing electronic device

Abstract

To provide a method for manufacturing an electronic device that can improve a yield in a step of dropping sheet-like solder to the inside of a through hole in a jig.SOLUTION: There is provided a method for manufacturing an electronic device for joining an electronic component or a conductive member being a member to be joined onto a substrate 5 by using solder 4, and the method includes, by using a jig 1 having a through hole 2 penetrating from a top face to an undersurface for locating the solder 4 and member to be joined, and an air relief area 3 connected with the through hole 2 at one end and connected with the outside at the other end, dropping the sheet-like solder 4 to the inside of the through hole 2 from a side of the top face of the jig 1, with the undersurface of the jig 1 brought into contact with the substrate 5, and releasing the air inside the through hole 2 from the air relief area 3.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a method for manufacturing an electronic device. [Background technology]

[0002] 2. Description of the Related Art In a manufacturing method of an electronic device in which members to be joined, such as electronic components, are joined onto a substrate by soldering, a jig may be used for positioning the sheet-like solder and the electronic components.

[0003] As a related technique, for example, Patent Document 1 is known.

[0004] The abstract of Patent Document 1 states, "A soldering jig for holding chips used when solder mounting a semiconductor chip 1 on a substrate 2, in which a chip insertion hole 4a corresponding to the external size of the chip is opened in a carbon jig 4, and the jig is placed on the substrate and solder mounted by passing through a soldering furnace with a solder tape 3 and a chip inserted into the hole, and a pocket 4b is formed around the bottom side of the insertion hole 4a to serve as an escape area for molten solder. This prevents the molten solder from flowing out into the narrow gap between the bottom of the jig and the substrate during soldering (capillary action), and allows an appropriate solder fillet to be formed in the pocket due to surface tension, enabling the chip to be soldered to the substrate."

[0005] Furthermore, paragraph 0005 of Patent Document 1 states, "When the conventional soldering jig described above is used, as shown in FIG. 4, the board 2 and the jig 4 are not completely in contact due to warping, uneven surfaces, etc., and a tiny gap g remains between the board 2 and the bottom surface of the jig 4. For this reason, when the jig 4 is loaded with the chip 1 and solder tape 3 set thereon as shown in FIG. 3 and then brought into a soldering furnace for soldering, the molten solder in the chip insertion hole 4a will flow out into the gap g due to capillary action." [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 5-343448 Summary of the Invention [Problem to be solved by the invention]

[0007] 10 and 11 are cross-sectional views illustrating the problems with the conventional method for manufacturing an electronic device.

[0008] As shown in Fig. 10, a substrate 5 is placed on a substrate under-jig 6, and with a jig 1 in contact with the upper surface of the substrate 5, a nozzle 7 is used to drop a sheet-like solder 4 into the inside of a through-hole 2. However, when the sheet-like solder 4 is particularly fine, there is a problem that, as shown in Fig. 11, the air pressure 9 inside the through-hole 2 may prevent the solder 4 from entering the inside of the through-hole 2 and may fly to a position outside the through-hole 2.

[0009] Note that Figures 2 and 4 of Patent Document 1 describe a case where "gap g remains" unintentionally. However, this type of "gap g" is so tiny that capillary action occurs, and it is not clear whether it is connected to the outside, so it is thought that the same problem will occur.

[0010] An object of the present invention is to provide a method for manufacturing an electronic device that can improve the yield in the step of dropping sheet-like solder into the inside of a through hole in a jig. [Means for solving the problem]

[0011] In order to solve the above-mentioned problems, the manufacturing method of an electronic device of the present invention is a manufacturing method of an electronic device in which a joined member, which is an electronic component or a conductive member, is joined to a substrate with solder, and is characterized in that a jig is used that has a through hole that penetrates from the top to the bottom surface for positioning the solder and the joined member, and an air escape area having one end connected to the through hole and the other end connected to the outside, and with the bottom surface of the jig abutted against the substrate, a sheet-like solder is dropped from the top surface side of the jig into the through hole, and air inside the through hole is allowed to escape from the air escape area. Effect of the Invention

[0012] According to the method for manufacturing an electronic device of the present invention, it is possible to improve the yield in the step of dropping sheet-like solder into the through hole of the jig. [Brief description of the drawings]

[0013] [Figure 1] 3A to 3C are top views illustrating the manufacturing method of the electronic device according to the first embodiment. [Diagram 2] Cross section AA of Figure 1. [Diagram 3] Cross-sectional view of FIG. 1 taken along line B-B. [Figure 4] 11A to 11C are top views illustrating a method for manufacturing an electronic device according to a second embodiment. [Diagram 5] Cross section AA of Figure 4. [Figure 6] 13A to 13C are top views illustrating a manufacturing method of an electronic device according to a third embodiment. [Figure 7] Cross-sectional view taken along line AA in Figure 6. [Figure 8] 13A to 13C are top views illustrating a method for manufacturing an electronic device according to a fourth embodiment. [Figure 9] Cross-sectional view taken along line AA in Figure 8. [Figure 10] 1A to 1C are cross-sectional views illustrating a problem with a conventional method for manufacturing an electronic device. [Figure 11] 1A to 1C are cross-sectional views illustrating a problem with a conventional method for manufacturing an electronic device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each drawing and each embodiment, the same or similar components are designated by the same reference numerals, and duplicated explanations will be omitted. EXAMPLES

[0015] Fig. 1 is a top view for explaining a method for manufacturing an electronic device according to Example 1. Fig. 2 is a cross-sectional view taken along line AA in Fig. 1. Fig. 3 is a cross-sectional view taken along line BB in Fig. 1.

[0016] The manufacturing method of the electronic device of the first embodiment includes a step of bonding an electronic component or conductive member (not shown) as a bonded member to a substrate 5 with solder 4. The electronic device is, for example, a semiconductor module. The electronic component as the bonded member is, for example, a semiconductor chip. The conductive member as the bonded member is, for example, a lead frame, a terminal, or a cylindrical sleeve into which the terminal is inserted.

[0017] 2, with jig 1 in contact with the upper surface of substrate 5, sheet-like solder 4 is dropped into through-hole 2 using nozzle 7. At this time, it is desirable to keep the upper surface of under-substrate jig 6 in contact with the lower surface of substrate 5.

[0018] Here, the jig 1 in this embodiment has a through hole 2 that penetrates from the top to the bottom and is used to position the solder 4 and a joined member (not shown), and an air escape area 3 with one end connected to the through hole 2 and the other end connected to the outside.

[0019] As shown in Figures 1 to 3, the air release area 3 in this embodiment is formed by a groove provided on the lower surface of the jig 1. While Figure 3 shows an example in which the groove has a triangular cross section, this is not limiting, and the groove may have another cross section, such as a rectangular, trapezoidal, or semicircular shape.

[0020] By providing the air release area 3 in the jig 1, when the sheet-like solder 4 is dropped from the upper surface of the jig 1 into the through-hole 2 with the lower surface of the jig 1 abutted against the board 5 as shown in Fig. 2, the air inside the through-hole 2 can be released from the air release area 3 as shown by air flow 8. In addition, because the air release area 3 is a groove provided on the lower surface of the jig 1, the air inside the through-hole 2 can be efficiently released until the sheet-like solder 4 has finished dropping. This makes it possible to drop the sheet-like solder 4 into the through-hole 2 with good yield.

[0021] After the solder 4 is dropped into the through hole 2, a member to be joined (not shown) is dropped into the through hole 2 from the upper surface side of the jig 1. The solder 4 is then heated to melt and then cooled to solidify, thereby joining the member to be joined to the substrate 5 with the solder 4. Note that after the solder 4 is dropped into the through hole 2, it may be heated to join the solder 4 onto the substrate 5 as preliminary solder, and then the member to be joined may be dropped into the through hole 2 and heated again to join.

[0022] The size of the air release area 3 is desirably set so that the through hole 2 does not enter the air release area 3 even if the position of the solder 4 is misaligned. For example, as shown in FIG. 3, it is desirably set so that the width of the groove in the air release area 3 is smaller than the width of the solder 4. In FIG. 3, the solder 4 is illustrated by a dotted line to indicate the size of the solder 4. However, this is not limited to this, and the height of the groove in the air release area 3 may be smaller than the thickness of the solder 4. In this case, the width of the groove in the air release area 3 may be smaller than, the same as, or larger than the width of the solder 4.

[0023] 3, by making the width of the groove in the air release region 3 smaller than the width of the solder 4, it is possible to prevent the solder 4 from entering the air release region 3 from the through hole 2, while by making the height of the groove in the air release region 3 larger than the thickness of the solder 4, it is possible to increase the cross-sectional area of ​​the groove in the air release region 3 and efficiently release air from the air release region 3. Furthermore, by making the height of the groove in the air release region 3 larger than the thickness of the solder 4, it is possible to efficiently release air even when the joined member is dropped from the upper surface side of the jig 1 into the through hole 2 after the solder 4 has been dropped into the through hole 2.

[0024] It is desirable that the maximum width of the groove in the air release area 3 be the minimum dimension of the dimensional tolerance of the width of the solder 4 minus 0.05 mm in order to prevent misalignment of the solder 4. For example, if the width of the solder 4 is 1.8±0.1 mm, the minimum dimension of the dimensional tolerance of the width of the solder 4 is 1.7 mm, from which 0.05 mm is subtracted to make the maximum groove width 1.65 mm. Taking into account the dimensional tolerance of the groove processing, it is desirable to set the design value of the groove width to, for example, 1.6±0.05 mm.

[0025] The through hole 2 may have a shape that matches the shape of the solder 4 and the member to be joined in order to position the solder 4 and the member to be joined. FIG. 1 shows an example of a circle, but the shape is not limited to this and may be other shapes such as a rectangle. The dimension of the through hole 2 is preferably set to the maximum dimension of the dimensional tolerance of the solder 4 + 0.05 mm in order to ensure that the solder 4 fits inside the through hole 2. For example, when the dimension of the solder 4 is 1.8 ± 0.1 mm, the maximum dimension of the dimensional tolerance of the solder 4 is 1.9 mm, and 0.05 mm is added to this to set the maximum dimension of the through hole 2 to 1.95 mm. Considering the dimensional tolerance of the processing of the through hole 2, it is preferable to set the design value of the dimension of the through hole 2 to, for example, 2.0 ± 0.05 mm. In addition, if the dimension of the through hole 2 is too large, the position of the solder 4 will be shifted significantly, so it is preferable to make the dimension of the through hole 2 as close to the minimum dimension as possible.

[0026] As a result of an experiment using the jig 1 of this embodiment, the solder 4 was able to be reliably dropped into the through hole 2 without being blown out of the through hole 2. In addition, the phenomenon in which the solder 4 is mounted at an angle inside the through hole 2 did not occur. EXAMPLES

[0027] Fig. 4 is a top view for explaining a method for manufacturing an electronic device according to Example 2. Fig. 5 is a cross-sectional view taken along the line AA in Fig. 4 .

[0028] Example 2 is a modification of Example 1, and is an example in which the air release area 3 is formed by a taper provided on the upper surface of the jig 1, as shown in FIG.

[0029] In the present embodiment, the effect of allowing air to escape from the air escape region 3 is the same as in embodiment 1. However, since there is no air escape region 3 in the region below the taper, there were cases where the solder 4 was blown out of the through hole 2 or where the solder 4 was mounted at an angle inside the through hole 2. Therefore, although the effect of allowing air to escape was obtained in this embodiment, embodiment 1 had a higher effect of improving the yield. EXAMPLES

[0030] Fig. 6 is a top view for explaining a manufacturing method of an electronic device according to Example 3. Fig. 7 is a cross-sectional view taken along the line AA in Fig. 6.

[0031] Example 3 is a modification of Example 1, and is an example in which the air release area 3 is formed by a groove provided along the side surface of the through hole 2 as shown in FIG. 6 and FIG.

[0032] As in the first embodiment, it is desirable that the size of the air release area 3 is such that even if the position of the solder 4 is misaligned, the solder will not enter the air release area 3 from the through hole 2. Therefore, it is desirable that the width of the groove in the air release area 3 is smaller than the width of the solder 4. Note that the idea of ​​taking into account the dimensional tolerance is the same as in the first embodiment, and therefore a repeated explanation will be omitted.

[0033] In the present embodiment, the effect of allowing air to escape from the air escape region 3 is the same as in embodiment 1. However, there were cases where the solder 4 was blown out of the through hole 2, or where the solder 4 was mounted at an angle inside the through hole 2. Therefore, although the effect of allowing air to escape was obtained in this embodiment, the effect of improving the yield was between that of embodiment 1 and embodiment 2. EXAMPLES

[0034] Fig. 8 is a top view for explaining a manufacturing method of an electronic device according to Example 4. Fig. 9 is a cross-sectional view taken along the line AA in Fig. 8.

[0035] The fourth embodiment is a combination of the first and third embodiments.

[0036] In the case of this embodiment, the solder 4 could be reliably dropped into the through hole 2 without being blown out of the through hole 2. However, there were cases where the solder 4 was mounted at an angle inside the through hole 2. Therefore, the yield improvement effect of this embodiment was between that of the first embodiment and the third embodiment.

[0037] Although the embodiments of the present invention have been described above, the present invention is not limited to the configurations described in the embodiments, and various modifications are possible within the scope of the technical concept of the present invention. In addition, some or all of the configurations described in each embodiment may be combined and applied.

[0038] For example, an embodiment in which the first embodiment and the second embodiment are combined, or an embodiment in which the first embodiment, the second embodiment, and the third embodiment are combined may be used. [Explanation of symbols]

[0039] 1 Jig 2 Through holes 3 Air release area 4 Solder 5 Substrate 6. Board Underside Fixture 7 Nozzles 8. Air flow 9. Pressure

Claims

1. A method for manufacturing an electronic device in which an electronic component or a conductive member is soldered onto a substrate, the method comprising the steps of: A jig is used, the jig having a through hole which penetrates from the upper surface to the lower surface and is used to position the solder and the joined member, and an air release area having one end connected to the through hole and the other end connected to the outside, A method for manufacturing an electronic device, characterized in that, with the underside of the jig abutting against the board, the sheet-like solder is dropped from the upper side of the jig into the inside of the through hole, and the air inside the through hole is allowed to escape through the air escape area.

2. In claim 1, A method for manufacturing an electronic device, wherein the air escape area is a groove provided on the underside of the jig.

3. In claim 2, A method for manufacturing an electronic device, wherein the groove has a width smaller than a width of the solder.

4. In claim 2, The method for manufacturing an electronic device, wherein the groove has a height smaller than a thickness of the solder.

5. In claim 2, The method for manufacturing an electronic device, wherein the groove has a width smaller than a width of the solder and a height greater than a thickness of the solder.

6. In claim 1, A method for manufacturing an electronic device, wherein the air escape area is a taper provided on an upper surface of the jig.

7. In claim 1, 2. A method for manufacturing an electronic device, comprising the steps of: forming a hole in a first region for guiding the air therethrough;

8. In claim 7, A method for manufacturing an electronic device, wherein the groove has a width smaller than a width of the solder.

9. In claim 1, A method for manufacturing an electronic device, comprising dropping the solder into the through hole, and then dropping the member to be joined from an upper surface side of the jig into the through hole.

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