Substrate manufacturing method
Patent Information
- Application Number
- PCT/JP2026/009214
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2025-03-21
- Filing Date
- 2026-03-10
- Publication Date
- 2026-09-24
Smart Images
Figure JP2026009214_24092026_PF_FP_ABST
Abstract
Description
Substrate Manufacturing Method
[0001] The present disclosure relates to a substrate manufacturing method.
[0002] Patent Document 1 discloses a soldering apparatus for an electronic unit, which performs reflow soldering by heating heat-resistant components (e.g., surface-mounted components) and non-heat-resistant components (e.g., lead components) mounted on a printed circuit board in a reflow furnace.
[0003] Japanese Patent No. 2924888
[0004] Incidentally, in a soldering process using a reflow furnace, the entire substrate is heated, so there is a risk that lead components with low heat resistance may be damaged by heat.
[0005] Therefore, in the invention of Patent Document 1, while heating surface-mounted components and lead components in a reflow furnace, cold air is blown onto the lead components such that the temperature on the lead component side is lower than the temperature on the surface-mounted component side.
[0006] However, the invention of Patent Document 1 requires the use of a reflow furnace having a hot air furnace and a cold air furnace, which poses a problem that the apparatus configuration becomes complicated.
[0007] Therefore, for lead components, which are components with low heat resistance for the reflow process, it is conceivable to solder them to the substrate in a process separate from the soldering process using a reflow furnace, but this has the problem of increasing the number of work steps.
[0008] An object of the present disclosure is to enable simultaneous soldering of surface-mounted components and lead components with a relatively simple configuration.
[0009] A first aspect of this disclosure is a method for manufacturing a substrate, comprising the steps of: applying solder paste (30) to a first surface (11) of a substrate (10) and to lead holes (16) formed in the substrate (10); temporarily attaching a first surface mount component (31) to the solder paste (30) applied to the first surface (11); temporarily attaching the lead wires (36) of a lead component (35) to the solder paste (30) by inserting them through the lead holes (16) from the first surface (11) side; and melting the solder paste (30) by heating the second surface (12) of the substrate (10) from the side opposite to the first surface (11), thereby soldering the first surface mount component (31) and the lead component (35) to the substrate (10).
[0010] In the first embodiment, by heating the second surface (12) of the substrate (10), it is possible to suppress the rise in ambient temperature on the first surface (11) and the temperature of the leaded components (35), thereby preventing the leaded components (35) located on the first surface (11) from being damaged by heat.
[0011] Furthermore, the solder paste (30) is melted by the heat transmitted through the substrate (10) from the second surface (12) to the first surface (11), and the first surface mount component (31) and the leaded component (35) are soldered simultaneously, thereby reducing the number of work steps.
[0012] A second aspect of the present disclosure is a substrate manufacturing method according to the first aspect, comprising the steps of: applying solder paste (30) to the second surface (12) of the substrate (10); and temporarily attaching a second surface mount component (32) to the solder paste (30) applied to the second surface (12), wherein the step of heating the second surface (12) melts the solder paste (30) on the second surface (12) to solder the second surface mount component (32) to the substrate (10).
[0013] In the second embodiment, by heating the second surface (12) side of the substrate (10), the first surface mount component (31) and lead component (35) arranged on the first surface (11) side can be soldered, and the second surface mount component (32) arranged on the second surface (12) side can also be soldered.
[0014] A third aspect of the present disclosure is a substrate manufacturing method according to the first or second aspect, wherein the substrate (10) comprises a base material portion (15) formed of a resin material and a heat conduction portion (70) extending in the thickness direction of the substrate (10) and having a higher thermal conductivity than the base material portion (15).
[0015] In the third embodiment, heat applied to the second surface (12) of the substrate (10) can be efficiently transferred from the second surface (12) to the first surface (11) by the heat conduction part (70).
[0016] A fourth aspect of the present disclosure is a substrate manufacturing method according to the third aspect, wherein the substrate (10) has through holes (80) formed therein, and the heat conductive portion (70) is composed of a heat conductive layer (75) that covers the inner circumferential surface of the through holes (80) in the substrate (10).
[0017] In the fourth embodiment, the heat conduction portion (70) can be formed by covering the inner circumferential surface of the through hole (80) in the substrate (10) with a heat conduction layer (75).
[0018] A fifth aspect of the present disclosure is a substrate manufacturing method according to the third aspect, wherein the substrate (10) has through holes (80) formed therein, and the heat conduction portion (70) is composed of solder paste (30) placed inside the through holes (80).
[0019] In the fifth embodiment, the heat conduction part (70) can be formed by placing solder paste (30) inside the through hole (80).
[0020] Figure 1 is a side cross-sectional view showing the configuration of a substrate manufacturing apparatus according to this embodiment 1. Figure 2 is a side cross-sectional view illustrating the state in which the solder paste on which the first surface mount component is temporarily attached is heated from the second surface side to melt it. Figure 3 is a side cross-sectional view showing the state in which the first surface mount component is soldered. Figure 4 is a side cross-sectional view illustrating the state in which the solder paste on which the lead component is temporarily attached is heated from the second surface side to melt it. Figure 5 is a side cross-sectional view showing the state in which the lead component is soldered. Figure 6 is a side cross-sectional view illustrating the state in this embodiment 2 in which the solder paste on which the second surface mount component is temporarily attached is heated from the second surface side to melt it. Figure 7 is a side cross-sectional view showing the state in which the second surface mount component is soldered. Figure 8 is a side cross-sectional view showing the configuration of the first heat conduction section in this embodiment 3. Figure 9 is a side cross-sectional view showing the configuration of the second heat conduction section. Figure 10 is a side cross-sectional view showing the configuration of the first heat conduction section in this embodiment 4. Figure 11 is a side cross-sectional view showing the configuration of the second heat conduction section. Figure 12 is a side cross-sectional view showing the configuration of a substrate manufacturing apparatus according to this embodiment 5. Figure 13 is a side cross-sectional view showing the configuration of a substrate manufacturing apparatus according to this embodiment 6.
[0021] <Embodiment 1> <Substrate> As shown in Figure 1, the substrate (10) has a base material portion (15), a first wiring portion (18), and a second wiring portion (20). The base material portion (15) is formed of an insulating plate material. The base material portion (15) is formed of, for example, a resin material. Lead holes (16) are formed in the base material portion (15). The lead holes (16) penetrate the base material portion (15) in the thickness direction.
[0022] The first wiring section (18) is provided on the first surface (11) side (top surface side in Figure 1) of the substrate (10). The first wiring section (18) is formed of a conductive material. For example, the first wiring section (18) is made of copper.
[0023] The second wiring section (20) is provided in the lead hole (16). The second wiring section (20) is made of a conductive material. For example, the second wiring section (20) is made of copper foil. The second wiring section (20) has a first wiring layer (21), a second wiring layer (22), and a third wiring layer (23).
[0024] The first wiring layer (21) is positioned to cover the peripheral edge of the lead hole (16) on the first surface (11) side of the substrate (10). The second wiring layer (22) is positioned to cover the peripheral edge of the lead hole (16) on the second surface (12) side (the bottom side in Figure 1) of the substrate (10) opposite to the first surface (11). The third wiring layer (23) is positioned to cover the inner peripheral surface of the lead hole (16) on the substrate (10). The first wiring layer (21), the second wiring layer (22), and the third wiring layer (23) are electrically connected to each other.
[0025] A solder paste (30) is applied to the first wiring section (18). A first surface mount component (31) is temporarily attached to the solder paste (30) applied to the first wiring section (18). The first surface mount component (31) is, for example, a heat-resistant component that has heat resistance to a reflow process using a reflow oven with an internal temperature of 250°C. The first surface mount component (31) is, for example, an integrated circuit.
[0026] A solder paste (30) is applied to the second wiring section (20). In the example shown in Figure 1, the solder paste (30) is applied to the second wiring layer (22) and the third wiring layer (23) of the second wiring section (20).
[0027] In the example shown in Figure 1, the solder paste (30) is applied to the second wiring layer (22) and the third wiring layer (23). However, the application location of the solder paste (30) is not limited to this configuration. For example, the solder paste (30) may be applied to the first wiring layer (21).
[0028] The lead wires (36) of the leaded component (35) are temporarily attached to the solder paste (30) applied to the second wiring section (20). The leaded component (35) is, for example, a low heat-resistant component that has low heat resistance to the reflow process. The leaded component (35) is, for example, a capacitor or a transformer. The leaded component (35) is temporarily attached to the solder paste (30) by inserting the lead wires (36) through the lead holes (16) from the first surface (11) side of the substrate (10).
[0029] The substrate (10), on which the first surface mount component (31) and leaded component (35) are temporarily attached with solder paste (30), is heated by a substrate manufacturing apparatus (50).
[0030] <Substrate Manufacturing Apparatus> The substrate manufacturing apparatus (50) comprises a mounting table (51), support legs (55), and a heating unit (60). A substrate (10) is placed on the mounting table (51). An opening hole (52) is formed in the mounting table (51) that penetrates in the thickness direction. The opening hole (52) opens along the outer edge of the substrate (10). The outer diameter of the opening hole (52) is smaller than the outer diameter of the substrate (10). The outer edge of the substrate (10) is held by the peripheral edge of the opening hole (52) in the mounting table (51).
[0031] This prevents components (the lead wires (36) of the lead component (35) in Figure 1) located on the second side (12) of the substrate (10) from interfering with the mounting base (51). Furthermore, the second side (12) of the substrate (10) is exposed through the opening (52) of the mounting base (51) and faces the heating section (60).
[0032] In the example shown in Figure 1, an opening (52) is formed in the mounting base (51) so that the second surface (12) of the substrate (10) is exposed through the opening (52) of the mounting base (51). However, the configuration is not limited to this form. For example, the mounting base (51) may be formed from a fence-like or mesh-like member so that the second surface (12) of the substrate (10) faces the heating section (60).
[0033] The support legs (55) support the mounting base (51) at a predetermined height. The support legs (55) are arranged, for example, at each of the four corners of the mounting base (51). Alternatively, the substrate (10) may be directly supported by the support legs (55) without providing a mounting base (51).
[0034] The heating unit (60) is positioned below the mounting base (51). The heating unit (60) is, for example, a heater. The heating unit (60) is positioned opposite the second surface (12) of the substrate (10). The heating unit (60) heats the second surface (12) of the substrate (10).
[0035] A first surface mount component (31) and a leaded component (35) are arranged on the first surface (11) side of the substrate (10). The heating unit (60) melts the solder paste (30) by heating the second surface (12) of the substrate (10) from the side opposite to the first surface (11).
[0036] Specifically, as shown in Figure 2, in the first surface mount component (31), heat from the heating section (60) is transferred to the solder paste (30) through the substrate section (15) and the first wiring section (18). In Figure 2, the direction of heat transfer is indicated by white arrow lines. As a result, the solder paste (30) to which the first surface mount component (31) is temporarily attached melts, and the first surface mount component (31) is soldered to the first wiring section (18) (see Figure 3).
[0037] As shown in Figure 4, in the lead component (35), heat from the heating element (60) is transferred to the solder paste (30) to which the lead component (35) is temporarily attached. In Figure 4, the direction of heat transfer is indicated by white arrow lines. The heat transferred to the solder paste (30) is also transferred to the first wiring layer (21) via the base material (15), the second wiring layer (22), and the third wiring layer (23).
[0038] As the solder paste (30) to which the lead component (35) is temporarily attached melts, the solder paste (30) flows through the lead holes (16) to the first surface (11) of the substrate (10), and the lead wires (36) of the lead component (35) are soldered to the second wiring section (20) of the substrate (10) (see Figure 5).
[0039] <Substrate Manufacturing Method> The following describes a substrate manufacturing method for producing a substrate (10) on which the first surface mount component (31) and leaded component (35) are soldered.
[0040] As shown in Figure 1, the process involves applying solder paste (30) to the first surface (11) of the substrate (10) and to the lead holes (16) formed in the substrate (10). For example, a metal mask is used to apply the solder paste (30) to the substrate (10).
[0041] A step of temporarily attaching the first surface-mount component (31) to the cream solder (30) applied to the first surface (11) is performed. Further, a step of inserting the lead wire (36) of the lead component (35) into the lead hole (16) from the first surface (11) side and temporarily attaching it to the cream solder (30) is performed.
[0042] The second surface (12) of the substrate (10) opposite to the first surface (11) is heated by a heating unit (60) from the second surface (12) side, thereby melting the cream solder (30) and soldering the first surface-mount component (31) and the lead component (35) to the substrate (10).
[0043] —Effect of the First Embodiment— According to the present embodiment, heating the second surface (12) side of the substrate (10) suppresses an increase in the atmospheric temperature on the first surface (11) side and the temperature of the lead component (35), thereby suppressing thermal damage to the lead component (35) disposed on the first surface (11) side.
[0044] Further, the cream solder (30) is melted by heat transferred through the inside of the substrate (10) from the second surface (12) toward the first surface (11), and the first surface-mount component (31) and the lead component (35) are soldered at the same time, whereby the number of work steps can be reduced.
[0045] <<Second Embodiment>> Hereinafter, the same parts as those in the first embodiment are denoted by the same reference numerals, and only the differences will be described.
[0046] As shown in FIG. 6, the substrate (10) includes a base material portion (15), a first wiring portion (18), a second wiring portion (20), and a third wiring portion (25).
[0047] The first wiring portion (18) is provided on the first surface (11) side of the substrate (10). The second wiring portion (20) is provided in the lead hole (16). The second wiring portion (20) includes a first wiring layer (21), a second wiring layer (22), and a third wiring layer (23).
[0048] The third wiring portion (25) is provided on the second surface (12) side of the substrate (10). The third wiring portion (25) is formed of a conductive material, for example, copper.
[0049] A solder paste (30) is applied to the first wiring section (18). The first surface mount component (31) is temporarily attached to the solder paste (30) applied to the first wiring section (18).
[0050] A solder paste (30) is applied to the second wiring section (20). In the example shown in Figure 6, the solder paste (30) is applied to the second wiring layer (22) and the third wiring layer (23) of the second wiring section (20). The lead wires (36) of the lead component (35) are temporarily attached to the solder paste (30) applied to the second wiring section (20). The lead component (35) is temporarily attached to the solder paste (30) by inserting the lead wires (36) into the lead holes (16) from the first surface (11) side of the substrate (10).
[0051] A solder paste (30) is applied to the third wiring section (25). A second surface mount component (32) is temporarily attached to the solder paste (30) applied to the third wiring section (25). The second surface mount component (32) is a heat-resistant component that has heat resistance to a reflow process using a reflow oven with an internal temperature of 250°C, for example. The second surface mount component (32) is an integrated circuit, for example.
[0052] The substrate (10), on which the first surface mount component (31), the second surface mount component (32), and the leaded component (35) are temporarily attached with solder paste (30), is heated by a substrate manufacturing apparatus (50).
[0053] A first surface mount component (31) and a leaded component (35) are arranged on the first side (11) of the substrate (10). A second surface mount component (32) is arranged on the second side (12) of the substrate (10). The heating unit (60) melts the solder paste (30) by heating the second side (12) of the substrate (10) from the second side (12).
[0054] Specifically, as shown in Figure 6, in the first surface mount component (31), heat from the heating unit (60) is transferred to the solder paste (30) through the substrate unit (15) and the first wiring unit (18), causing the solder paste (30) to melt. As a result, the first surface mount component (31) is soldered to the first wiring unit (18) of the substrate (10) (see Figure 7).
[0055] In the lead component (35), heat from the heating element (60) is transferred to the solder paste (30) to which the lead component (35) is temporarily attached, causing the solder paste (30) to melt. As a result, the lead wires (36) of the lead component (35) are soldered to the second wiring section (20) of the circuit board (10) (see Figure 7).
[0056] In the case of the second surface mount component (32), heat from the heating unit (60) is transferred to the solder paste (30) to which the second surface mount component (32) is temporarily attached, causing the solder paste (30) to melt. As a result, the second surface mount component (32) is soldered to the third wiring section (25) of the substrate (10) (see Figure 7).
[0057] <Substrate Manufacturing Method> The following describes a substrate manufacturing method for producing a substrate (10) on which a first surface mount component (31), a second surface mount component (32), and a leaded component (35) are soldered.
[0058] As shown in Figure 6, the process involves applying solder paste (30) to the first surface (11) of the substrate (10), the second surface (12) of the substrate (10), and the lead holes (16) formed in the substrate (10). For example, a metal mask is used to apply the solder paste (30) to the substrate (10).
[0059] The first surface mount component (31) is temporarily attached to the solder paste (30) applied to the first surface (11). The lead wires (36) of the lead component (35) are inserted through the lead holes (16) from the first surface (11) side and temporarily attached to the solder paste (30). Furthermore, the second surface mount component (32) is temporarily attached to the solder paste (30) applied to the second surface (12).
[0060] The process involves heating the second surface (12) of the substrate (10) from the side opposite to the first surface (11) using a heating unit (60) to melt the solder paste (30) and solder the first surface mount component (31), the second surface mount component (32), and the leaded component (35) to the substrate (10).
[0061] -Effects of this second embodiment- According to this embodiment, by heating the second surface (12) side of the substrate (10), the first surface mount component (31) and lead component (35) arranged on the first surface (11) side can be soldered, and the second surface mount component (32) arranged on the second surface (12) side can also be soldered.
[0062] <Embodiment 3> As shown in Figures 8 and 9, the substrate (10) has a base material portion (15), a first wiring portion (18), a second wiring portion (20), and a heat conduction portion (70). The heat conduction portion (70) includes a first heat conduction portion (71) and a second heat conduction portion (72).
[0063] The base material (15) has a first insulating layer (41), a second insulating layer (42), and a third insulating layer (43). The first insulating layer (41) is located on the first surface (11) side of the substrate (10). The third insulating layer (43) is located on the second surface (12) side of the substrate (10). The second insulating layer (42) is located between the first insulating layer (41) and the third insulating layer (43). The first insulating layer (41), the second insulating layer (42), and the third insulating layer (43) are formed from, for example, a resin material. The first insulating layer (41), the second insulating layer (42), and the third insulating layer (43) are formed integrally.
[0064] The first wiring section (18) is positioned between the first insulating layer (41) and the second insulating layer (42). The first wiring section (18) is made of a conductive material. For example, the first wiring section (18) is made of copper. By removing a portion of the first insulating layer (41), a portion of the first wiring section (18) is exposed on the first surface (11) side of the substrate (10).
[0065] A solder paste (30) is applied to the first wiring section (18) exposed on the first surface (11). A first surface mount component (31) is temporarily attached to the solder paste (30) applied to the first wiring section (18).
[0066] Multiple through holes (80) are formed in the base material (15) that penetrate in the thickness direction. The through holes (80) include first through holes (81) and second through holes (82). Multiple first through holes (81) are formed around the first surface mount component (31) at intervals in the circumferential direction. Multiple second through holes (82) are formed around the lead component (35) at intervals in the circumferential direction.
[0067] The first heat conduction portion (71) extends in the thickness direction of the substrate (10) and is formed of a material with a higher thermal conductivity than the base material portion (15). Specifically, the first heat conduction portion (71) is composed of a heat conduction layer (75) that covers the inner circumferential surface of the first through hole (81) in the base material portion (15). The heat conduction layer (75) is formed of, for example, copper foil. The end of the heat conduction layer (75) on the first surface (11) side of the substrate (10) is electrically connected to the first wiring portion (18).
[0068] As shown in Figure 9, lead holes (16) are formed in the substrate portion (15). The second wiring portion (20) is provided in the lead holes (16). The second wiring portion (20) has a first wiring layer (21), a second wiring layer (22), and a third wiring layer (23). The first wiring layer (21) is arranged to cover the peripheral edge of the lead hole (16) on the first surface (11) side of the substrate (10). The second wiring layer (22) is arranged to cover the peripheral edge of the lead hole (16) on the second surface (12) of the substrate (10). The third wiring layer (23) is arranged to cover the inner circumferential surface of the lead hole (16) on the substrate (10). The first wiring layer (21), the second wiring layer (22), and the third wiring layer (23) are electrically connected to each other.
[0069] The first wiring layer (21) is placed between the first insulating layer (41) and the second insulating layer (42). By removing a portion of the first insulating layer (41), a portion of the first wiring layer (21) is exposed on the first surface (11) side of the substrate (10).
[0070] The second wiring layer (22) is placed between the second insulating layer (42) and the third insulating layer (43). By removing a portion of the third insulating layer (43), a portion of the second wiring layer (22) is exposed on the second surface (12) side of the substrate (10).
[0071] A solder paste (30) is applied to the second wiring section (20). In the example shown in Figure 9, the solder paste (30) is applied to the first wiring layer (21) and the third wiring layer (23) of the second wiring section (20) that are exposed on the first surface (11) side. Lead components (35) are temporarily attached to the solder paste (30) applied to the second wiring section (20). The lead components (35) are temporarily attached to the solder paste by inserting lead wires (36) into lead holes (16) from the first surface (11) side of the substrate (10).
[0072] In the example shown in Figure 9, the solder paste (30) is applied to the first wiring layer (21) and the third wiring layer (23). However, the application location of the solder paste (30) is not limited to this configuration. For example, the solder paste (30) may be applied to the second wiring layer (22).
[0073] The second heat conduction portion (72) extends in the thickness direction of the substrate (10) and is formed of a material with a higher thermal conductivity than the base material portion (15). Specifically, the second heat conduction portion (72) is composed of a heat conduction layer (75) that covers the inner circumferential surface of the second through hole (82) in the base material portion (15). The heat conduction layer (75) is formed of, for example, copper foil.
[0074] The end of the thermal conductive layer (75) on the first surface (11) side of the substrate (10) is electrically connected to the first wiring layer (21) of the second wiring section (20). The end of the thermal conductive layer (75) on the second surface (12) side of the substrate (10) is electrically connected to the second wiring layer (22) of the second wiring section (20).
[0075] As shown in Figures 8 and 9, a first surface mount component (31) and a leaded component (35) are arranged on the first surface (11) side of the substrate (10). The heating unit (60) melts the solder paste (30) by heating the second surface (12) of the substrate (10) from the second surface (12) side.
[0076] As shown in Figure 8, in the first surface mount component (31), heat from the heating section (60) is transferred to the solder paste (30) through the substrate section (15) and the first wiring section (18). In Figure 8, the direction of heat transfer is indicated by white arrow lines. Furthermore, heat from the heating section (60) is transferred to the solder paste (30) through the first heat conduction section (71) and the first wiring section (18). As a result, the solder paste (30) to which the first surface mount component (31) is temporarily attached melts, and the first surface mount component (31) is soldered to the first wiring section (18) of the substrate (10).
[0077] As shown in Figure 9, in the lead component (35), heat from the heating element (60) is transferred to the solder paste (30) through the substrate (15) and the second wiring element (20). In Figure 9, the direction of heat transfer is indicated by the white-filled arrow lines. Furthermore, heat from the heating element (60) is transferred to the solder paste (30) through the second heat conduction element (72) and the second wiring element (20). As a result, the solder paste (30) to which the lead component (35) is temporarily attached melts, and the lead component (35) is soldered to the second wiring element (20) of the substrate (10).
[0078] -Effects of this third embodiment- According to this embodiment, the heat applied to the second surface (12) of the substrate (10) can be efficiently transferred from the second surface (12) to the first surface (11) by the heat conduction part (70).
[0079] According to this embodiment, a heat conduction portion (70) can be formed by covering the inner circumferential surface of the through hole (80) in the substrate (10) with a heat conduction layer (75).
[0080] <Embodiment 4> Hereinafter, the same reference numerals will be used for the same parts as in Embodiment 3, and only the differences will be described.
[0081] As shown in Figures 10 and 11, the substrate (10) has a base material portion (15), a first wiring portion (18), a second wiring portion (20), and a heat conduction portion (70). The heat conduction portion (70) includes a first heat conduction portion (71) and a second heat conduction portion (72).
[0082] A solder paste (30) is applied to the first wiring section (18) exposed on the first surface (11). A first surface mount component (31) is temporarily attached to the solder paste (30) applied to the first wiring section (18).
[0083] Multiple through holes (80) are formed in the base material (15) that penetrate in the thickness direction. The through holes (80) include first through holes (81) and second through holes (82). Multiple first through holes (81) are formed around the first surface mount component (31) at intervals in the circumferential direction. Multiple second through holes (82) are formed around the lead component (35) at intervals in the circumferential direction.
[0084] The first heat conduction portion (71) extends in the thickness direction of the substrate (10) and is formed of a material with a higher thermal conductivity than the base material portion (15). Specifically, the first heat conduction portion (71) consists of a heat conduction layer (75) that covers the inner circumferential surface of the first through hole (81) in the base material portion (15) and solder paste (30) placed inside the first through hole (81).
[0085] The thermal conductive layer (75) is formed of, for example, copper foil. The end of the thermal conductive layer (75) on the first surface (11) side of the substrate (10) is electrically connected to the first wiring section (18).
[0086] As shown in Figure 11, lead holes (16) are formed in the base material (15). The second wiring section (20) is provided in the lead holes (16). The second wiring section (20) has a first wiring layer (21), a second wiring layer (22), and a third wiring layer (23).
[0087] A solder paste (30) is applied to the second wiring section (20). In the example shown in Figure 11, the solder paste (30) is applied to the second wiring layer (22) and the third wiring layer (23) of the second wiring section (20) that is exposed on the second surface (12) side. Lead components (35) are temporarily attached to the solder paste (30) applied to the second wiring section (20). The lead components (35) are temporarily attached to the solder paste by inserting lead wires (36) into lead holes (16) from the first surface (11) side of the substrate (10).
[0088] The second heat conduction portion (72) extends in the thickness direction of the substrate (10) and is formed of a material with a higher thermal conductivity than the base material portion (15). Specifically, the second heat conduction portion (72) consists of a heat conduction layer (75) that covers the inner circumferential surface of the second through hole (82) in the base material portion (15) and solder paste (30) placed inside the heat conduction layer (75). The heat conduction layer (75) is formed of, for example, copper foil.
[0089] As shown in Figures 10 and 11, a first surface mount component (31) and a leaded component (35) are arranged on the first surface (11) side of the substrate (10). The heating unit (60) melts the solder paste (30) by heating the second surface (12) of the substrate (10) from the second surface (12) side.
[0090] As shown in Figure 10, in the first surface mount component (31), heat from the heating section (60) is transferred to the solder paste (30) through the substrate section (15) and the first wiring section (18). In Figure 10, the direction of heat transfer is indicated by white arrow lines. Furthermore, heat from the heating section (60) is transferred to the solder paste (30) to which the first surface mount component (31) is temporarily attached, through the first heat conduction section (71) and the first wiring section (18). As a result, the solder paste (30) to which the first surface mount component (31) is temporarily attached melts, and the first surface mount component (31) is soldered to the first wiring section (18) of the substrate (10).
[0091] As shown in Figure 11, in the lead component (35), heat from the heating element (60) is transferred to the solder paste (30) to which the lead component (35) is temporarily attached. In Figure 11, the direction of heat transfer is indicated by white arrow lines. Furthermore, the heat from the heating element (60) is transferred to the first wiring layer (21) through the second heat conduction element (72).
[0092] As the solder paste (30) to which the lead component (35) is temporarily attached melts, the solder paste (30) flows through the lead hole (16) to the first surface (11) of the substrate (10), and the lead component (35) is soldered to the second wiring section (20) of the substrate (10).
[0093] -Effects of this embodiment 4- According to this embodiment, a heat conduction part (70) can be formed by placing solder paste (30) inside the through hole (80).
[0094] Embodiment 5: As shown in Figure 12, the substrate manufacturing apparatus (50) comprises a mounting table (51), support legs (55), a heating unit (60), and a blower fan (65). A substrate (10) is placed on the mounting table (51). The support legs (55) support the mounting table (51) at a predetermined height.
[0095] The heating unit (60) is positioned below the mounting base (51). The heating unit (60) is, for example, a heater. The heating unit (60) is positioned opposite the second surface (12) of the substrate (10). The heating unit (60) heats the second surface (12) of the substrate (10).
[0096] The blower fan (65) is positioned below the heating section (60). The blower fan (65) supplies the heat generated in the heating section (60) as hot air to the second surface (12) of the substrate (10).
[0097] -Effects of Embodiment 5- According to this embodiment, the second surface (12) of the substrate (10) becomes easier to heat, and the solder paste (30) can be melted.
[0098] Embodiment 6: As shown in Figure 13, the substrate manufacturing apparatus (50) comprises a soldering bath (90), a heating unit (60), and a transport unit (100).
[0099] The soldering bath (90) has an internal containment space (91). An inert liquid (98) is stored in the lower part of the soldering bath (90). An air layer (92) is formed above the liquid (98) in the containment space (91).
[0100] The heating element (60) is, for example, a heater. The heating element (60) is placed in the liquid (98) stored at the bottom of the soldering bath (90). The heating element (60) heats and evaporates the liquid (98), forming a saturated vapor layer (93) above the liquid (98). An interface layer (94) is formed between the saturated vapor layer (93) and the air layer (92). The proportion of saturated vapor contained in the interface layer (94) is less than the proportion of saturated vapor contained in the saturated vapor layer (93).
[0101] The transport unit (100) comprises a mounting table (51), a moving mechanism (96), and a wire (97). A substrate (10) is placed on the mounting table (51). An opening (52) is formed in the mounting table (51) that penetrates in the thickness direction of the substrate. The opening (52) opens along the outer edge of the substrate (10). The outer diameter of the opening (52) is smaller than the outer diameter of the substrate (10). The outer edge of the substrate (10) is held by the peripheral edge of the opening (52) in the mounting table (51).
[0102] In the example shown in Figure 13, an opening (52) is formed in the mounting base (51), exposing the second surface (12) of the substrate (10) through the opening (52) of the mounting base (51). However, the configuration is not limited to this form. For example, the mounting base (51) may be formed from a fence-like or mesh-like member.
[0103] The outer periphery of the substrate (10) is surrounded by a partition member (45). The partition member (45) is formed in a cylindrical shape that surrounds the outer periphery of the substrate (10) and extends above the upper surface of the substrate (10). The partition member (45) is placed on the mounting base (51) together with the substrate (10).
[0104] The mounting base (51) and the partition member (45) are placed in the housing space (91) of the soldering bath (90). The partition member (45) separates the air layer (92) above the upper surface of the substrate (10) from the saturated vapor layer (93).
[0105] Multiple detection sensors (95) are provided in the soldering bath (90). The detection sensors (95) are, for example, temperature sensors. The multiple detection sensors (95) are provided on the inner wall of the soldering bath (90). In the example shown in Figure 13, the detection sensors (95) are embedded in the inner wall of the soldering bath (90) so as not to interfere with the mounting table (51) which moves in the vertical direction. Note that the arrangement of the detection sensors (95) is not limited to this, and any arrangement is acceptable as long as it does not interfere with the mounting table (51).
[0106] Multiple detection sensors (95) are arranged with spacing between them in the vertical direction. In the example shown in Figure 13, three detection sensors (95) are placed in positions corresponding to the air layer (92), the saturated vapor layer (93), and the interface layer (94). Note that the number and arrangement of detection sensors (95) are not limited to this.
[0107] The detection sensor (95) detects the position of the interface layer (94) between the air layer (92) and the saturated vapor layer (93). Specifically, by detecting the temperature inside the containment space (91) using multiple detection sensors (95), the position of the interface layer (94) is detected based on the temperature distribution inside the containment space (91).
[0108] The moving mechanism (96) consists of, for example, a hoisting machine that winds up the wire (97). The lower end of the wire (97) is attached to the mounting base (51). The moving mechanism (96) changes the height position of the substrate (10) and the partition member (45) by moving the mounting base (51) in the vertical direction.
[0109] The transport unit (100) moves the substrate (10) and the partition member (45) based on the detected position of the interface layer (94). The transport unit (100) moves the substrate (10) and the partition member (45) to a position where the lower surface of the substrate (10) is in contact with the saturated vapor layer (93). Specifically, the substrate (10) and the partition member (45) should be moved to a position where the lower surface of the substrate (10) is below the interface layer (94) between the air layer (92) and the saturated vapor layer (93), and the upper end of the partition member (45) is above the interface layer (94).
[0110] At this time, the air layer (92) above the upper surface of the substrate (10) and the saturated vapor layer (93) are separated by the partition member (45).
[0111] Furthermore, the transport unit (100) is not limited to a configuration in which the wire (97) is wound up by a moving mechanism (96) as shown in Figure 13, but can take any form as long as the mounting platform (51) is movable in the vertical direction.
[0112] A first surface mount component (31) and a leaded component (35) are placed on the first side (11) of the substrate (10). A second surface mount component (32) is placed on the second side (12) of the substrate (10). The substrate manufacturing apparatus (50) melts the solder paste (30) by heating the second side (12) of the substrate (10) from the second side (12).
[0113] Specifically, the second surface (12) of the substrate (10) is heated by the latent heat of condensation of saturated vapor in the saturated vapor layer (93). In the first surface mount component (31), the heat applied to the second surface (12) of the substrate (10) is transferred to the solder paste (30) through the base material (15) and the first wiring section (18), causing the solder paste (30) to melt. As a result, the first surface mount component (31) is soldered to the first wiring section (18) of the substrate (10).
[0114] In the lead component (35), the heat applied to the second surface (12) of the circuit board (10) is transferred to the solder paste (30) to which the lead component (35) is temporarily attached, causing the solder paste (30) to melt. As a result, the lead wires (36) of the lead component (35) are soldered to the second wiring section (20) of the circuit board (10).
[0115] In the case of the second surface mount component (32), the heat applied to the second surface surface mount component (10) is transferred to the solder paste (30) to which the second surface mount component (32) is temporarily attached, causing the solder paste (30) to melt. As a result, the second surface mount component (32) is soldered to the third wiring section (25) of the substrate (10).
[0116] -Effects of Embodiment 6- According to this embodiment, by moving the substrate (10) and the partition member (45) to a position where the lower surface of the substrate (10) is in contact with the saturated vapor layer (93), the solder paste (30) can be melted by the latent heat of condensation of the saturated vapor, and the first surface mount component (31) and leaded component (35) can be soldered to the substrate (10).
[0117] Furthermore, by separating the air layer (92) above the upper surface of the substrate (10) from the saturated vapor layer (93) using the partition member (45), saturated vapor is prevented from flowing to the upper surface of the substrate (10), thereby suppressing thermal damage to the lead components (35).
[0118] 《Other Embodiments》 Although embodiments and modifications have been described above, it will be understood that various changes in form and details are possible without departing from the spirit and scope of the claims. Furthermore, elements of the above embodiments, modifications, and other embodiments may be combined or substituted as appropriate. In addition, the descriptions "first," "second," "third," etc. in the specification and claims are used to distinguish the phrases to which these descriptions are attached, and do not limit the number or order of such phrases.
[0119] As explained above, this disclosure is useful for substrate manufacturing methods.
[0120] 10 Substrate 11 First surface 12 Second surface 15 Base material 16 Lead hole 30 Solder paste 31 First surface mount component 32 Second surface mount component 35 Lead component 36 Lead wire 50 Substrate manufacturing equipment 70 Heat conduction section 75 Heat conduction layer 80 Through hole
Claims
1. A method for manufacturing a substrate, comprising the steps of: applying solder paste (30) to a first surface (11) of a substrate (10) and to lead holes (16) formed in the substrate (10); temporarily attaching a first surface mount component (31) to the solder paste (30) applied to the first surface (11); temporarily attaching the lead wires (36) of a lead component (35) to the solder paste (30) by inserting them through the lead holes (16) from the first surface (11) side; and melting the solder paste (30) by heating the second surface (12) of the substrate (10) from the side opposite to the first surface (11), thereby soldering the first surface mount component (31) and the lead component (35) to the substrate (10).
2. A substrate manufacturing method according to claim 1, comprising the steps of: applying solder paste (30) to the second surface (12) of the substrate (10); and temporarily attaching a second surface mount component (32) to the solder paste (30) applied to the second surface (12), wherein the step of heating the second surface (12) involves melting the solder paste (30) on the second surface (12) to solder the second surface mount component (32) to the substrate (10).
3. A method for manufacturing a substrate according to claim 1 or 2, wherein the substrate (10) comprises a base material portion (15) formed of a resin material and a heat conduction portion (70) extending in the thickness direction of the substrate (10) and having a higher thermal conductivity than the base material portion (15).
4. A substrate manufacturing method according to claim 3, wherein the substrate (10) has through holes (80) formed therein, and the heat conductive portion (70) is composed of a heat conductive layer (75) that covers the inner circumferential surface of the through holes (80) in the substrate (10).
5. A substrate manufacturing method according to claim 3, wherein the substrate (10) has through holes (80) formed therein, and the heat conduction portion (70) is composed of solder paste (30) placed inside the through holes (80).