Circuit board and method for manufacturing mounting board

Abstract

This circuit board is provided with: a base material having a main surface; a first terminal and a second terminal provided on the main surface of the base material; and a wall of an insulating material provided on the main surface of the base material, the wall having at least one groove penetrating from the inner peripheral surface to the outer peripheral surface, the first terminal and the second terminal being disposed in a cavity surrounded by the wall, and the first terminal and the second terminal being disposed in a first direction orthogonal to the main surface of the base material. When a reference shape of a rectangular shape which is externally connected with the minimum area of the inner peripheral surface of the wall is set, at least one of the first terminal and the second terminal is provided with a part which is configured from the reference shape to the outer peripheral side through the groove part.

Description

Technical Field

[0001] The present disclosure relates to a method for manufacturing a circuit substrate and a mounting substrate. Background Art

[0002] In recent years, with the continuous development of electronicization, the development of technology for mounting electronic components on substrates has also been continuously improved. For example, a technology has been developed for mounting multiple bare chips of semiconductor light-emitting elements represented by light-emitting diodes (hereinafter referred to as "LEDs") used for lighting or display devices on a wiring substrate. For example, in Japanese Patent Publication No. 2006-93523, an invention is disclosed for inserting and joining semiconductor light-emitting elements in a cavity in which multiple semiconductor light-emitting elements can be easily positioned and arranged. In addition, in Japanese Patent Publication No. 2009-71138, an invention is disclosed for providing an electrode joint portion in a cavity and inserting an electronic component in the cavity in a manner of joining with the electrode joint portion. Summary of the invention

[0003] Here, in a structure such as Patent Document 1, electronic components move in the cavity, and the orientation of components such as LED components is inconsistent. In a structure such as Patent Document 2, when the electronic components are miniaturized, the cavity is also miniaturized. In this case, the terminals in the cavity also need to be reduced. However, due to problems such as the resolution limit of the resist and the exposure device, it is difficult to form a small-sized pattern with high positional accuracy, and there are problems such as reduced quality due to dimensional deviation, etc., which leads to reduced yield.

[0004] An object of the present disclosure is to provide a method for manufacturing a circuit board and a mounting board that can suppress quality degradation and accurately position electronic components.

[0005] The present disclosure relates to a circuit substrate comprising: a substrate having a main surface; a first terminal and a second terminal, which are arranged on the main surface of the substrate; and a wall of an insulating material, which is arranged on the main surface of the substrate, the wall having at least one groove portion penetrating from the inner peripheral surface to the outer peripheral surface, the first terminal and the second terminal are arranged in a cavity surrounded by the wall, and, when viewed from a first direction orthogonal to the main surface of the substrate, when a reference shape of a rectangle with a minimum area circumscribed to the inner peripheral surface of the wall is set, at least one of the first terminal and the second terminal has: a portion arranged from the reference shape to the outer peripheral side via the groove portion.

[0006] The present disclosure relates to a method for manufacturing a mounting substrate, wherein the mounting substrate is manufactured by mounting electronic components on the circuit substrate. The mounting substrate may be configured by configuring constituent materials on a base material and configuring electronic components, and then bonding the electronic components to terminals using a pressurized reflow device.

[0007] According to the present disclosure, a method for manufacturing a circuit board and a mounting board capable of suppressing quality degradation and accurately positioning electronic components is provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is a schematic cross-sectional view showing a mounting substrate including a circuit board according to an embodiment of the present disclosure.

[0009] Figure 2 It is a schematic cross-sectional view showing a circuit board according to an embodiment of the present disclosure.

[0010] Figure 3 It is a top view of the circuit board.

[0011] Figure 4 This is a diagram showing the wall frame portion as viewed from the thickness direction.

[0012] Figure 5 This is a schematic cross-sectional view showing a method for manufacturing a circuit board and a mounting board.

[0013] Figure 6 This is a schematic cross-sectional view showing a method for manufacturing a circuit board and a mounting board.

[0014] Figure 7 This is a schematic cross-sectional view showing a method for manufacturing a wall portion.

[0015] Figure 8 It is a schematic cross-sectional view showing a circuit board according to a comparative example.

[0016] Fig. 9 It is a schematic cross-sectional view showing a circuit board according to a comparative example.

[0017] Fig.10 It is a conceptual diagram for explaining the effects of the comparative example and the embodiment.

[0018] Fig.11 It is a diagram showing a circuit board according to a modification.

[0019] Fig.12 It is a diagram showing a circuit board according to a modification.

[0020] Fig.13 It is a diagram showing a circuit board according to a modification.

[0021] Fig.14 It is a diagram showing a circuit board according to a modification.

[0022] Fig.15 It is a diagram showing a circuit board according to a modification.

[0023] Description of Reference Numerals

[0024] 1…mounting substrate; 2…electronic component; 3…circuit substrate; 4A…joining material; 8…base material; 9…wall; 10A…terminal (first terminal); 10B…terminal (second terminal); 30…groove; 30A, 30B…groove (first groove); 30C, 30D, 30E, 30F…groove (second groove); 40A…frame (first frame); 40B…frame (second frame); 49…pressurized reflow soldering device. DETAILED DESCRIPTION

[0025] Reference Figure 1 to Figure 3 , the circuit substrate 3 involved in the embodiment of the present disclosure is described. Figure 1 It is a schematic cross-sectional view showing a mounting substrate 1 including a circuit substrate 3 according to an embodiment of the present disclosure. Figure 2 It is a schematic cross-sectional view showing the circuit board 3 according to the embodiment of the present disclosure. Figure 3 It is a top view of the circuit board 3.

[0026] like Figure 1 As shown, the mounting substrate 1 includes an electronic component 2 and a circuit board 3. The mounting substrate 1 is configured by mounting the electronic component 2 on the circuit board 3 via a bonding material 4.

[0027] The electronic component 2 includes a main body 6 and a pair of terminals 7. The main body 6 is a member for performing the function as the electronic component 2. The terminal 7 is a metal portion formed on the main surface of the main body 6. As the material of the terminal 7, a metal such as Cu, Ti, Au, Ni, Sn, Bi, P, B, In, Ag, Zn, Pd, Mo, Pt, Cr, or an alloy of at least two selected from these metals can be used. The electronic component 2 is composed of, for example, a micro LED. The micro LED is a component that emits light based on the input from the circuit board 3.

[0028] The circuit board 3 includes a substrate 8, a wall 9, and a pair of terminals 10 (a first terminal and a second terminal). The substrate 8 is a flat main body of the circuit board 3. The substrate 8 has a main surface 8a. The substrate 8 can be a printed circuit board for mounting the conductor patterns and electronic components of the circuit board 3 on the main surface 8a. As the material of the substrate 8, a known resin material or ceramic material for a printed circuit board can be used. In addition, in the following description, the XYZ coordinates set for the circuit board 3 are sometimes used for description. The X-axis direction (second direction) is a direction parallel to the main surface 8a of the substrate 8, the Y-axis direction (third direction) is a direction parallel to the main surface 8a of the substrate 8 and orthogonal to the X-axis direction, and the Z-axis direction (first direction) is a direction orthogonal to the main surface 8a of the substrate 8.

[0029] The wall 9 of the insulating material is provided on the main surface 8a of the substrate 8. The wall 9 is a member formed of the insulating material. The wall 9 protrudes from the substrate 8 toward the positive side in the Z-axis direction. Figure 3 As shown, in the present embodiment, wall 9 has wall frame parts 13A, 13B, 13C, 13D that are arranged around. Wall frame parts 13A, 13B are opposite to each other in the state of being separated from each other in the X-axis direction, and expand in parallel to the Y-axis direction. Wall frame parts 13A are configured on the positive side of the X-axis direction, and wall frame parts 13B are configured on the negative side. Wall frame parts 13C, 13D are opposite to each other in the state of being separated from each other in the Y-axis direction, and expand in parallel to the X-axis direction. Wall frame parts 13C are configured on the positive side of the Y-axis direction, and wall frame parts 13D are configured on the negative side. Wall frame parts 13A connects the ends of the positive side of the X-axis direction of wall frame parts 13C, 13D to each other. Wall frame parts 13B connects the ends of the negative side of the X-axis direction of wall frame parts 13C, 13D to each other. Thus, from the Z-axis direction, wall 9 has a rectangular frame-shaped structure. The wall frame parts 13A and 13B constitute the short side, and the wall frame parts 13C and 13D constitute the long side. In addition, the size is not particularly limited, and the size of the wall frame parts 13A and 13B in the Y-axis direction can be set to 10μm to 60μm. The size of the wall frame parts 13C and 13D in the X-axis direction can be set to 15μm to 70μm. The size of the short side of the inner peripheral surface inside the wall 9 can be set to more than 8μm and less than 44μm. The size of the long side of the inner peripheral surface inside the wall 9 can be more than 15μm and less than 68μm. The size of the short side of the inner peripheral surface inside the wall 9 is the size of the inner peripheral surface 13a of the wall frame part 13C and the inner peripheral surface 13a of the wall frame part 13D in the Y-axis direction. The size of the long side of the inner peripheral surface inside the wall 9 is the size of the inner peripheral surface 13a of the wall frame part 13A and the inner peripheral surface 13a of the wall frame part 13B in the X-axis direction. As the material of the wall 9, for example, resin materials such as epoxy resin, acrylic resin, phenolic resin, melamine resin, urea resin, and alkyd resin can be used. As the material of the wall 9, epoxy resin and acrylic resin are particularly preferably used.

[0030] like Figure 1 to Figure 3 As shown, the terminal 10 is a metal portion provided on the main surface 8a of the substrate 8. As the material of the terminal 10, Ni, Cu, Ti, Cr, Al, Mo, Pt, Au, or an alloy of at least two selected from these can be used. A conductive film 12 is formed on the upper surface of the terminal 10. As the material of the conductive film 12, a film of Ti, Cu, Ni, Al, Mo, Cr, Ag, etc., or a film of mixed metal particles and a binder can be used.

[0031] The bonding material 4 is a member for bonding the terminal 7 of the electronic component 2 and the terminal 10 of the circuit board 3. The bonding material 4 is formed by thermally bonding the bonding material 4A on the circuit board 3 side and the bonding material 4B on the electronic component 2 side to form an integrated structure (see Figure 6). The bonding material 4 may contain Sn or may be composed of an alloy containing Sn. However, the bonding material 4 is not necessarily limited to containing Sn. In addition to Sn, the bonding material 4 may also be composed of an alloy containing an element that lowers the melting point of Sn. As an element that lowers the melting point of Sn, for example, Bi and the like can be cited. The bonding material 4 functions as a solder. Thus, between the substrate 8 and the main body 6, the terminal 10, the conductive film 12, the bonding material 4, and the terminal 7 are stacked in sequence from the upper surface of the substrate 8. In addition, at this location, solder bonding is performed after stacking the terminal 10, the conductive film 12, the bonding material 4, and the terminal 7. Therefore, after solder bonding, the metals of the terminal 10, the conductive film 12, the bonding material 4, and the terminal 7 form a melt-diffused structure. Such a structure after solder bonding may be a structure containing a brittle intermetallic compound (IMC). In the presence of an intermetallic compound with a brittle structure, it is easy to break due to stress from the outside, so the reliability is easily reduced. Therefore, by surrounding the electronic component 2 with the wall 9 , an effect of protecting the electronic component 2 is produced.

[0032] The wall 9 has a cavity 11. The cavity 11 is formed by a through hole that penetrates the wall 9 in the Z-axis direction. Thus, the upper surface of the substrate 8 is exposed at the bottom side of the cavity 11. The cavity 11 is rectangular when viewed from the Z-axis direction (see FIG. Figure 3 The terminals 7, 10, conductive film 12 and bonding material 4 are arranged in a cavity 11 surrounded by the wall 9, so that the surroundings are surrounded by the wall 9. A small gap is formed between the terminals 7, 10, conductive film 12 and bonding material 4 and the inner peripheral surface 13a of the wall frame parts 13A, 13B, 13C, and 13D constituting the surroundings of the cavity 11.

[0033] In the cavity 11, a constituent material 20 is arranged between the electronic component 2 and the bonding material 4 and the wall 9. Thus, by being supported by the constituent material 20, it is possible to make it difficult for the electronic component 2 to be peeled off from the circuit substrate 3. In addition, the force applied to the electronic component 2, the bonding material 4, the terminals 7 and 10 can be alleviated, thereby improving reliability. As the material of the constituent material 20, for example, epoxy resin, acrylic resin, phenolic resin, melamine resin, urea resin, alkyd resin or a mixture of these, or a mixture of the resin material with SiOx, ceramics, etc. can be used. As the material of the constituent material 20, epoxy resin and acrylic resin are particularly preferably used. The viscosity of the constituent material 20 during filling is preferably 1Pa to 20Pa, and more preferably 5Pa to 10Pa.

[0034] like Figure 2 As shown, the circuit substrate 3 has Figure 1The mounting substrate 1 shown in the figure is a structure in which the electronic component 2 and the constituent material 20 are removed. In addition, in the circuit substrate 3, the bonding material 4A containing a metal element is arranged on the upper side of the terminal 10 (the upper surface of the conductive film 12). The circuit substrate 3 includes: a bonding material 4A (first bonding material) arranged on the positive side of the X-axis direction on the terminal 10A, and a bonding material 4A (second bonding material) arranged on the negative side of the X-axis direction on the terminal 10B. As described above, these bonding materials 4A constitute a part of the bonding material 4 in the pre-stage of thermally bonding the electronic component 2 to the mounting substrate 1. In the state of the circuit substrate 3, a pair of terminals 10, the conductive film 12 and the bonding material 4A are arranged in the wall 9 formed by the insulator.

[0035] like Figure 3 As shown, wall 9 has at least one groove 30 that penetrates from inner peripheral surface 13a to outer peripheral surface 13b. In the present embodiment, wall 9 has a groove 30A in wall frame 13C and a groove 30B in wall frame 13D. For wall frame 13C, 13D, the Y-axis direction is the thickness direction. Therefore, the grooves 30A, 30B of wall frame 13C, 13D extend along the Y-axis direction and penetrate wall frame 13C, 13D. In addition, groove 30 is formed in at least one of wall frame 13A, 13B, 13C, 13D. In addition, multiple grooves 30 can also be formed in any of wall frame 13A, 13B, 13C, 13D. In addition, grooves 30 (details will be described later) can also be formed in the corners of each wall frame 13A, 13B, 13C, 13D.

[0036] Secondly, refer to Figure 4 , the structure of the wall frame portion 13C when viewed from the thickness direction will be described. Figure 4 (a) is a diagram of the wall frame portion 13C viewed from the Y-axis direction, which is the thickness direction. Figure 4 Although the wall frame portion 13C is shown in FIG. 1 , the same main contents of the description also apply to the other wall frame portion 13D. Figure 4 As shown in (a), when viewed from the Y-axis direction which is the thickness direction of the wall frame portion 13C, the groove portion 30 extends from the front end portion 13c in the height direction of the wall frame portion 13C (in the Z-axis direction in the present embodiment) toward the substrate 8 side (the negative side in the Z-axis direction). The groove portion 30 has a bottom surface 30a and a pair of side surfaces 30b. The bottom surface 30a is formed on the negative side in the Z-axis direction relative to the front end portion 13c. The pair of side surfaces 30b extend from both ends of the bottom surface 30a in the X-axis direction toward the front end portion 13c. Figure 4 In the example shown in (a) of FIG. 8 , the groove portion 30 reaches the main surface 8 a of the substrate 8 .

[0037] like Figure 4As shown in (b), the width of the groove 30 in the X-axis direction, which is the width direction, is larger on the front end 13c side than on the bottom surface 30a side. The width of the groove 30 at the top end 13c is larger than the width of the groove 30 at the bottom surface 30a. Figure 4 In the example shown in (b), the groove portion 30 opens widely in the X-axis direction toward the front end portion 13c. The pair of side surfaces 30b are inclined so that the distance between them increases toward the positive side in the Z-axis direction.

[0038] In addition, the width of the groove portion 30 is not particularly limited as long as it is not too small to discharge the remaining constituent material 20. For example, the width of the groove portion 30 can be 1 μm or more, or 4 μm or more. In addition, the wall frame portion 13 can be set to a larger width as long as it has a size that can position the electronic component 2.

[0039] like Figure 3 As shown, the wall 9 has an L-shaped frame 40A (first frame) and an L-shaped frame 40B (second frame). The frames 40A and 40B are configured to be rotationally symmetrical with respect to the central axis CL of the cavity 11. The central axis CL is set by a virtual line extending in a direction orthogonal to the substrate 8 relative to the center position of a rectangular reference shape T1 described later (see also Figure 2 ). Rotational symmetry means that when the shape of one side is rotated 180° around the central axis CL, it is in a relationship of being consistent with the shape of the other side. The frame 40A, 40B is formed by dividing the rectangular annular wall 9 rotationally symmetrical with respect to the central axis CL into a pair of grooves 30A, 30B. Therefore, the grooves 30A, 30B are also configured to be rotationally symmetrical with respect to the central axis CL.

[0040] The groove 30A formed in the wall frame portion 13C is formed on the positive side of the X-axis direction relative to the center axis CL. The side surface 30b on the positive side of the groove 30A in the X-axis direction is arranged at the same position in the X-axis direction so as to become a continuous surface with the inner peripheral surface 13Aa of the wall frame portion 13A, and extends in the Y-axis direction. The side surface 30b on the negative side of the groove 30A in the X-axis direction is arranged at a position separated from the inner peripheral surface 13Aa toward the negative side of the X-axis direction. Figure 3 In the figure, the side surface 30b on the negative side of the groove portion 30A in the X-axis direction is arranged at a position closer to the positive side of the X-axis direction than the center axis CL in the X-axis direction, but can also be arranged at the same position as the center axis CL or at a position on the negative side of the X-axis direction.

[0041] The groove 30B formed in the wall frame portion 13D is formed on the negative side of the X-axis direction relative to the center axis CL. The side surface 30b on the negative side of the X-axis direction of the groove 30B is arranged at the same position in the X-axis direction so as to become a continuous surface with the inner peripheral surface 13Ba of the wall frame portion 13B, and extends in the Y-axis direction. The side surface 30b on the positive side of the X-axis direction of the groove 30B is arranged at a position separated from the inner peripheral surface 13Ba toward the positive side of the X-axis direction. Figure 3 In the figure, the side surface 30b on the positive side of the groove portion 30B in the X-axis direction is arranged at a position closer to the negative side of the X-axis direction than the center axis CL in the X-axis direction, but can also be arranged at the same position as the center axis CL or at a position on the positive side of the X-axis direction.

[0042] Frame 40A has: the first side 41A extending in the Y-axis direction, and the second side 42A extending in the X-axis direction. The first side 41A is composed of a part of wall frame 13A and wall frame 13C. A part of wall frame 13C is a part of the wall frame 13C that is closer to the positive side of the X-axis direction than groove 30A. The second side 42A is composed of a part of wall frame 13D. A part of wall frame 13D is a part of the wall frame 13D that is closer to the positive side of the X-axis direction than groove 30B.

[0043] Frame 40B has: the first side 41B extending in the Y-axis direction, and the second side 42B extending in the X-axis direction. The first side 41B is composed of a part of wall frame 13B and wall frame 13D. A part of wall frame 13D is a part of the negative side of the wall frame 13D that is closer to the X-axis direction than groove 30B. The second side 42B is composed of a part of wall frame 13C. A part of wall frame 13C is a part of the negative side of the wall frame 13C that is closer to the X-axis direction than groove 30A.

[0044] Here, a rectangular ring-shaped reference shape T1 is set for the cavity 11. The reference shape T1 is a virtual shape with the minimum area that is circumscribed to the inner peripheral surface 13a of the wall 9 when viewed from the height direction (Z-axis direction). Figure 3 In the present embodiment, the reference shape T1 has a rectangular shape with the X-axis direction as the longitudinal direction.

[0045] Reference shape T1 has a pair of long sides Sc and Sd extending along the X-axis direction as the long side direction. A pair of long sides Sc and Sd are separated from each other in the Y-axis direction. The long side Sc on the positive side of the Y-axis direction has: a line segment described by a part of the inner peripheral surface 13Ca of the wall frame portion 13C, and a line segment that crosses the groove portion 30A in the X-axis direction as a virtual extension line of the inner peripheral surface 13Ca. The long side Sd on the negative side of the Y-axis direction has: a line segment described by a part of the inner peripheral surface 13Da of the wall frame portion 13D, and a line segment that crosses the groove portion 30B in the X-axis direction as a virtual extension line of the inner peripheral surface 13Da.

[0046] The reference shape T1 has a pair of short sides Sa and Sb extending in the Y-axis direction as the short side direction. The pair of short sides Sa and Sb are separated from each other in the X-axis direction. The short side Sa on the positive side of the X-axis direction has a line segment drawn by the inner peripheral surface 13Aa of the wall frame portion 13A. The short side Sb on the negative side of the X-axis direction has a line segment drawn by the inner peripheral surface 13Ba of the wall frame portion 13B.

[0047] The electronic component 2 (indicated by a virtual line) disposed in the cavity 11 is positioned by a pair of frames 40A and 40B. The frames 40A and 40B use the inner circumferential surfaces 13Aa, 13Ba, 13Ca, and 13Da as limiting surfaces to position the electronic component 2. Therefore, the electronic component 2 inserted into the cavity 11 is automatically positioned by the inner circumferential surfaces 13Aa, 13Ba, 13Ca, and 13Da, and is configured to be contained within the range of the reference shape T1. That is, the electronic component 2 is positioned in a manner that does not protrude from the reference shape T1 to the outer peripheral side. When the electronic component 2 is accurately configured in a manner that the central axis CL of the cavity 11 is consistent, the gap between the outer circumferential surface of the electronic component 2 and the inner circumferential surfaces 13Aa, 13Ba, 13Ca, and 13Da of the wall 9 is set to a range of 0 μm to 5.0 μm. When the gap is too large, the positioning accuracy is reduced, and when the gap is too small, the insertion of the electronic component 2 into the cavity 11 becomes difficult. By setting the gap to the above range, positioning can be performed easily and accurately.

[0048] For the frame bodies 40A, 40B and the cavity 11 as described above, a pair of terminals 10 are formed on the main surface 8a of the substrate 8. The pair of terminals 10 have a structure that is rotationally symmetrical with each other around the center axis CL. The pair of terminals 10 have a portion that is arranged toward the periphery from the reference shape T1. The terminal 10A (first terminal) is arranged on the positive side in the X-axis direction relative to the center axis CL. The terminal 10A extends from the portion where the terminal 7 of the electronic component 2 is arranged toward the positive side in the Y-axis direction within the reference shape T1. The terminal 10A extends toward the periphery (the positive side in the Y-axis direction) relative to the long side Sc of the reference shape T1, and is arranged in the groove portion 30A. In the groove portion 30A, on the main surface 8a of the substrate 8 (refer to Figure 4 ) is formed with a terminal 10A. In the groove portion 30A, the terminal 10A extends to the position of the outer peripheral surface 13Cb, but there is no particular limitation on the position to which the groove portion 30A extends. In the present embodiment, the terminal 10A has: a portion configured only from one long side Sc (the long side on the positive side in the Y-axis direction) of the rectangular reference shape T1 toward the outer peripheral side.

[0049] The terminal 10B (second terminal) is arranged on the positive side of the X-axis direction relative to the center axis CL. The terminal 10B extends from the portion where the terminal 7 of the electronic component 2 is arranged to the negative side of the Y-axis direction in the reference shape T1. The terminal 10B extends to the outer peripheral side (negative side of the Y-axis direction) relative to the long side Sd of the reference shape T1 and is arranged in the groove portion 30B. In the groove portion 30B, on the main surface 8a of the substrate 8 (refer to Figure 4 ) is formed on the terminal 10B. In the groove portion 30B, the terminal 10B extends to the position of the outer peripheral surface 13Db, but there is no particular limitation on the position to which the groove portion 30B extends. In the present embodiment, the terminal 10B has: only a portion configured from one long side Sd (the long side on the negative side of the Y-axis direction) of the rectangular reference shape T1 to the outer peripheral side.

[0050] The minimum opening dimension A of the grooves 30A and 30B is less than the short side dimension B of the electronic component 2 mounted on the terminals 10A and 10B. In the present embodiment, the grooves 30A and 30B extend from the inner peripheral surfaces 13Ca and 13Da along the Y-axis direction with a certain width and open at the outer peripheral surfaces 13Cb and 13Db. Therefore, the width dimension of the grooves 30A and 30B itself is the minimum opening dimension A of the grooves 30A and 30B.

[0051] Reference Figure 5 and Figure 6 , the manufacturing method of the circuit substrate 3 and the mounting substrate 1 is described. First, Figure 5 As shown in (a), a terminal 10 is formed on the upper surface of the substrate 8. Figure 5 As shown in (b), a wall 9 is formed on the base material 8. Thus, the circuit board 3 is completed. Figure 5 In (b), a conductive film 12 and a bonding material 4A are formed on the upper surface of the terminal 10. Next, as Figure 5 As shown in (c), the constituent material 20 is filled in the cavity 11, thereby configuring the constituent material 20 on the substrate 8. Furthermore, the electronic component 2 is held by the holding member and the electronic component 2 is mounted in the cavity 11. Next, as Figure 6As shown, for the electronic component 2, the electronic component 2 is pressed into the cavity 11 by the pressurized reflow device 49, and the bonding material 4A and the bonding material 4B are brought into contact with each other inside the constituent material 20. At this time, a part of the constituent material 20 is moved toward the groove portion 30 (see Figure 3 ) is pressed out. Next, the bonding material 4B of the electronic component 2 is bonded to the bonding material 4A of the base material 8 by heating. Thus, the mounting substrate 1 is completed. In addition, in this process, the electronic component 2 is positioned in the cavity 11 by the frame bodies 40A and 40B (refer to Figure 3 ).

[0052] Secondly, refer to Figure 7 , a method for forming the wall 9 having the groove 30 is described. First, Figure 7 As shown in (a), a wall 9 is formed on a substrate 8. Next, as Figure 7 As shown in (b), the wall 9 is irradiated with laser light by the laser device 51, thereby processing a part of the wall 9. Figure 7 As shown in (c) , a groove portion 30 is formed in the wall 9 .

[0053] Or, if Figure 7 As shown in (d) of FIG. 8 , a resist 52 is formed on the substrate 8. Next, as shown in FIG. Figure 7 As shown in (e), exposure is performed using a glass mask 53 having a pattern corresponding to the shape of the wall 9 having the groove portion 30. Figure 7 As shown in (f) of FIG. 8 , the wall 9 having the groove portion 30 is formed by developing the exposed resist 52 .

[0054] Next, the operation and effects of the method for manufacturing the circuit board 3 and the mounting board 1 according to the present embodiment will be described.

[0055] First, refer to Figure 8 and Fig. 9 , the circuit substrate 103 involved in the comparative example is described. Figure 8 As shown, the wall 9 of the circuit substrate 103 does not have the above-mentioned groove portion 30. When the electronic component 2 is miniaturized, the cavity 11 is also miniaturized. At this time, the terminal 10 must be arranged in the range surrounded by the inner circumference 13a of the wall 9, so it is necessary to reduce the terminal 10 in the cavity 11. However, due to problems such as the resolution limit of the resist and the exposure device, it is difficult to form a small-sized pattern with high position accuracy, and there are problems such as reduced quality due to dimensional deviation and the like, resulting in reduced yield. In addition, for example, when the wall 9 overlaps with the terminal 10, defects occur in the pattern formation of the terminal 10. In the case where the wall 9 and the terminal 10 cannot be overlapped in this way, the gap GP between the inner circumference 13a and the terminal 10 must be set to a size that takes into account the alignment accuracy and dimensional deviation of the exposure device. In this case, the cavity 11 becomes larger and the positioning accuracy of the electronic component 2 is reduced.

[0056] In addition, if Fig. 9 As shown, after the constituent material 20 is filled inside the wall 9, the electronic component 2 is mounted inside the wall 9 using a holding member, and when the electronic component 2 is pressed in using a pressurized reflow soldering device, the electronic component 2 cannot be fully pressed in due to the influence of the remaining constituent material 20. In this case, the bonding material 4B of the electronic component 2 and the bonding material 4A of the circuit board 3 are reflowed while being kept separate, and there is a possibility that a poor connection between the bonding material 4A of the circuit board 3 and the electronic component 2 may occur.

[0057] In this regard, in the circuit substrate 3 involved in the present embodiment, the terminal 10A (first terminal) and the terminal 10B (second terminal) are arranged in the cavity 11. Therefore, when the electronic component 2 is mounted on the circuit substrate 3, the electronic component 2 is inserted into the cavity 11, and is bonded to the terminals 10A and 10B via the bonding material 4A. At this time, the electronic component 2 is positioned by the inner peripheral surface 13a of the wall 9. Therefore, in the case of miniaturization of the electronic component 2, it is also possible to accurately position the electronic component 2 by reducing the size of the cavity 11. In the case of setting a rectangular reference shape T1 with the minimum area of ​​the inner peripheral surface 13a of the wall 9 when viewed from the Z-axis direction (first direction), if the terminals 10A and 10B are accommodated within the range of the reference shape T1, as described above, the terminals 10A and 10B need to be reduced along with the miniaturization of the cavity 11. In contrast, in the circuit substrate 3 according to the present embodiment, at least one groove 30 is formed in the wall 9, which passes through from the inner peripheral surface 13a to the outer peripheral surface 13b. In this way, by providing the groove 30 in the wall 9, it is possible to ensure that the groove 30 is used as a space for configuring the terminals 10A and 10B. At least one of the terminals 10A and 10B has a portion configured from the reference shape T1 to the outer peripheral side via the groove 30. Therefore, by utilizing the space closer to the outer peripheral side than the reference shape T1, it is possible to suppress at least one of the terminals 10A and 10B from becoming excessively smaller. As a result, the difficulty of pattern formation of the terminals 10A and 10B can be reduced, and the quality can be stabilized. As described above, it is possible to suppress quality degradation and accurately position the electronic component 2.

[0058] In addition, the wall 9 has at least one groove 30 extending from the inner peripheral surface 13a to the outer peripheral surface 13b. In this case, the constituent material 20 is arranged in the cavity 11, the electronic component 2 is mounted using a holding member, and the electronic component 2 is pressed into the cavity 11 using a pressurized reflow soldering device to be heated and bonded to the circuit substrate 3, so that when the electronic component 2 is mounted on the circuit substrate 3, the remaining constituent material 20 can be discharged to the outside of the wall 9 through the groove 30. Therefore, in the pressurization process using the pressurized reflow soldering device, the electronic component 2 can be fully pressed into the cavity 11 and brought into contact with the bonding material 4.

[0059] The wall 9 has an L-shaped frame 40A (first frame) and an L-shaped frame 40B (second frame), and the frames 40A and 40B can be configured to be rotationally symmetrical with respect to the central axis CL of the cavity 11. In this case, by using the rotationally symmetrical L-shaped frames 40A and 40B, the electronic component 2 can be positioned with good balance from all sides. Fig.10 As shown in (a), in 103 involved in the comparative example, when the cavity 11 is larger than the electronic component 2, the inner peripheral surface 13a surrounds the entire circumference. In this case, when a plurality of electronic components 2 are positioned in each cavity 11, each electronic component 2 is positionally shifted in a non-uniform direction. On the other hand, in the circuit substrate 3 involved in the present embodiment, by using rotationally symmetric frames 40A and 40B, even if it is assumed that the position of the electronic component 2 is shifted in the cavity 11, the rotational direction of the position shift can be made uniform. In this case, when the electronic component 2 emits light, the overall non-uniformity of the light-emitting position can be suppressed compared to the case of non-uniform shift in the comparative example. In addition, by making the direction of the position shift uniform, it is easy to detect NG products under inspection.

[0060] The minimum opening size A of the groove 30 may be less than the short side size B of the electronic component 2 that can be mounted on the terminals 10A and 10B. In this case, even if the electronic component 2 rotates or deviates in the cavity 11, it can be restrained from moving outward from the groove 30 and confined in the cavity 11.

[0061] At least one of the terminals 10A and 10B may have a portion disposed only from one side of the rectangular reference shape T1 toward the outer circumference. In this case, the size of the groove 30 can be reduced, and rotation or displacement of the electronic component 2 in the cavity 11 can be suppressed.

[0062] The circuit board 3 may include: a bonding material 4A (first bonding material) containing a metal element disposed on the terminal 10A; and a bonding material 4A (second bonding material) containing a metal element disposed on the terminal 10B. In this case, the electronic component 2 may be mounted on the terminals 10A and 10B via the bonding material 4A.

[0063] The manufacturing method of the mounting substrate 1 involved in this embodiment can be a manufacturing method of the mounting substrate 1 by mounting the electronic component 2 on the above-mentioned circuit substrate 3 to manufacture the mounting substrate 1, after configuring the constituent material 20 on the substrate 8 and configuring the electronic component 2, using a pressurized reflow soldering device 49 to connect the electronic component 2 to the terminal 10.

[0064] In this case, the same main functions and effects as those of the above-mentioned circuit board 3 can be obtained.

[0065] The present disclosure is not limited to the above-described embodiment. For example, the number and arrangement of the terminals of the circuit board are not particularly limited.

[0066] The structure of the wall 9 is not limited to the above-mentioned embodiment. Fig.11 The structure shown. Fig.11 The circuit board 3 shown in the figure has a groove 30 extending in the X-axis direction, and the terminals 10A and 10B extend in the X-axis direction. Fig.11 In the example, the groove 30A extends to the positive side of the X-axis direction in the wall frame portion 13A to form a side 30b continuous with the inner peripheral surface 13Ca. The groove 30B extends to the negative side of the X-axis direction in the wall frame portion 13B to form a side 30b continuous with the inner peripheral surface 13Da. Thus, the frame 40A has: a first side 41A extending in a short range along the Y-axis direction on the positive side of the X-axis direction, and a second side 42A extending in a long scale along the X-axis direction on the negative side of the Y-axis direction. The frame 40B has: a first side 41B extending in a short range along the Y-axis direction on the negative side of the X-axis direction, and a second side 42B extending in a long scale along the X-axis direction on the positive side of the Y-axis direction.

[0067] The terminal 10A extends further toward the outer periphery (positive side in the X-axis direction) than the short side Sa of the reference shape T1, and is arranged in the groove portion 30A. The terminal 10A has a portion arranged toward the outer periphery only from one short side Sa (the short side on the positive side in the X-axis direction) of the rectangular reference shape T1. The terminal 10B extends further toward the outer periphery (negative side in the X-axis direction) than the short side Sb of the reference shape T1, and is arranged in the groove portion 30B. The terminal 10B has a portion arranged toward the outer periphery only from one short side Sb (the short side on the negative side in the X-axis direction) of the rectangular reference shape T1.

[0068] For example, you can also use Fig.12 The structure shown. Fig.12The circuit substrate 3 shown has a large groove 30A at the corner between the wall frame 13A and 13C, and has a large groove 30B at the corner between the wall frame 13B and 13D. The side 30b of the wall frame 13A side of the groove 30A extends in the X-axis direction at a position closer to the negative side of the Y-axis direction than the central axis CL. The side 30b of the wall frame 13C side of the groove 30A extends in the Y-axis direction at a position closer to the positive side of the X-axis direction than the central axis CL. The side 30b of the wall frame 13B side of the groove 30B extends in the X-axis direction at a position closer to the positive side of the Y-axis direction than the central axis CL. The side 30b of the wall frame 13D side of the groove 30B extends in the Y-axis direction at a position closer to the negative side of the X-axis direction than the central axis CL. Thus, the frame 40A has a first side portion 41A extending in a short range along the Y-axis direction on the positive side in the X-axis direction, and a second side portion 42A extending in the X-axis direction on the negative side in the Y-axis direction. The frame 40B has a first side portion 41B extending in a short range along the Y-axis direction on the negative side in the X-axis direction, and a second side portion 42B extending in the X-axis direction on the positive side in the Y-axis direction.

[0069] The terminal 10A extends further toward the outer periphery (positive side in the Y-axis direction) than the long side Sc of the reference shape T1, and is arranged in the groove portion 30A. The terminal 10A has a portion that is arranged only toward the outer periphery from one long side Sc (long side on the positive side in the Y-axis direction) of the rectangular reference shape T1. The terminal 10B extends further toward the outer periphery (negative side in the Y-axis direction) than the long side Sd of the reference shape T1, and is arranged in the groove portion 30B. The terminal 10B has a portion that is arranged only toward the outer periphery from one long side Sd (long side on the negative side in the Y-axis direction) of the rectangular reference shape T1.

[0070] In addition, if Fig.12 In the above example, the minimum opening dimension A of the groove 30 may be larger than the short side dimension B of the electronic component 2. However, the opening dimension A may be smaller than the short side dimension B by reducing the size of the groove 30.

[0071] You can also use Fig.13 The structure shown. Fig.13 The circuit substrate 3 shown is compared to Fig.12, widen the terminals 10A and 10B. The terminal 10A extends further toward the outer periphery (positive side in the Y-axis direction) than the long side Sc of the reference shape T1, and extends further toward the outer periphery (positive side in the X-axis direction) than the short side Sa, and is arranged in the groove portion 30A. The terminal 10B extends further toward the outer periphery (negative side in the Y-axis direction) than the long side Sd of the reference shape T1, and extends further toward the outer periphery (negative side in the X-axis direction) than the short side Sb, and is arranged in the groove portion 30B. In this way, the terminals 10A and 10B can have portions arranged toward the outer periphery from multiple directions relative to the reference shape T1.

[0072] Alternatively, you can use Fig.14 The structure shown. Fig.14 In the circuit board 3 shown, the wall 9 is formed with grooves 30, which include: grooves 30A and 30B (first grooves) equipped with terminals 10A and 10B; and grooves 30C and 30D (second grooves) not equipped with terminals 10A and 10B. In this case, when the electronic component 2 is pressed into the cavity 11 and excess constituent material 20 is generated, it can be discharged to the outside of the cavity through the grooves 30C and 30D. Fig.14 In, relative to Fig.13 The wall 9 shown has a narrow groove 30C formed at a corner between the wall frame portions 13A and 13D, and a narrow groove 30D formed at a corner between the wall frame portions 13B and 13C.

[0073] Alternatively, you can use Fig.15 The structure shown. Fig.15 The circuit substrate 3 shown is relative to Fig.14 In the illustrated wall 9 , a narrow groove 30E extending in the Y-axis direction is formed in the wall frame portion 13D, and a narrow groove 30F extending in the Y-axis direction is formed in the wall frame portion 13C.

[0074] In addition, in the above-mentioned embodiments and modified examples, both the terminal 10A (first terminal) and the terminal 10B (second terminal) have a portion disposed from the reference shape to the outer peripheral side via the groove portion. However, at least one of the terminal 10A (first terminal) and the terminal 10B (second terminal) may have a portion disposed from the reference shape to the outer peripheral side via the groove portion, and the other terminal may not have a portion disposed from the reference shape to the outer peripheral side.

[0075] (Method 1)

[0076] A circuit substrate, wherein:

[0077] have:

[0078] a substrate having a major surface;

[0079] a first terminal and a second terminal, which are provided on the main surface of the substrate; and a wall of an insulating material, which is provided on the main surface of the substrate,

[0080] The wall has at least one groove extending from the inner peripheral surface to the outer peripheral surface.

[0081] The first terminal and the second terminal are disposed in a cavity surrounded by the wall, and

[0082] When observed from a first direction orthogonal to the main surface of the substrate, in the case of a rectangular reference shape with a minimum area of ​​the inner peripheral surface circumscribed to the wall, at least one of the first terminal and the second terminal has: a portion configured from the reference shape to the outer peripheral side via the groove.

[0083] (Method 2)

[0084] The circuit substrate according to aspect 1, wherein

[0085] The wall has: an L-shaped first frame body and an L-shaped second frame body.

[0086] The first frame body and the second frame body are configured to be rotationally symmetrical with respect to the central axis of the cavity.

[0087] (Method 3)

[0088] The circuit substrate according to aspect 1 or 2, wherein:

[0089] The minimum opening dimension of the groove portion is equal to or smaller than a short side dimension of an electronic component that can be mounted on the first terminal and the second terminal.

[0090] (Method 4)

[0091] The circuit board according to any one of aspects 1 to 3, wherein

[0092] The at least one terminal has a portion disposed only from one side of the rectangular reference shape toward the outer peripheral side.

[0093] (Method 5)

[0094] The circuit board according to any one of aspects 1 to 4, wherein

[0095] The wall includes, as the groove portion, a first groove portion in which the at least one terminal is arranged, and a second groove portion in which the at least one terminal is not arranged.

[0096] (Method 6)

[0097] The circuit board according to any one of aspects 1 to 5, wherein

[0098] The invention comprises: a first bonding material which is disposed on the first terminal and contains a metal element; and a second bonding material which is disposed on the second terminal and contains a metal element.

[0099] (Method 7)

[0100] A method for manufacturing a mounting substrate, wherein:

[0101] The mounting substrate is manufactured by mounting an electronic component on the circuit substrate according to any one of the embodiments 1 to 6,

[0102] After the constituent materials are arranged on the substrate and the electronic component is arranged, the electronic component is bonded to the first terminal and the second terminal using a pressure reflow device.

Claims

1. A circuit substrate, wherein: have: a substrate having a major surface; A first terminal and a second terminal are provided on the main surface of the substrate; and a wall of insulating material provided on the main surface of the substrate, The wall has at least one groove extending from the inner peripheral surface to the outer peripheral surface. The first terminal and the second terminal are disposed in a cavity surrounded by the wall, and When viewed from a first direction orthogonal to the main surface of the substrate, when a rectangular reference shape with a minimum area of ​​the inner peripheral surface circumscribed to the wall is set, at least one of the first terminal and the second terminal has: a portion configured from the reference shape to the outer peripheral side via the groove.

2. The circuit substrate according to claim 1, wherein: The wall has an L-shaped first frame body and an L-shaped second frame body. The first frame body and the second frame body are configured to be rotationally symmetrical with respect to the central axis of the cavity.

3. The circuit substrate according to claim 1, wherein: The minimum opening dimension of the groove portion is equal to or smaller than a short side dimension of an electronic component that can be mounted on the first terminal and the second terminal.

4. The circuit substrate according to claim 1, wherein: The at least one terminal has a portion disposed only from one side of the rectangular reference shape toward the outer peripheral side.

5. The circuit substrate according to claim 1, wherein: The wall includes, as the groove portion, a first groove portion in which the at least one terminal is arranged, and a second groove portion in which the at least one terminal is not arranged.

6. The circuit substrate according to claim 1, wherein: The invention comprises: a first bonding material which is disposed on the first terminal and contains a metal element; and a second bonding material which is disposed on the second terminal and contains a metal element.

7. A method for manufacturing a mounting substrate, wherein: The mounting substrate is manufactured by mounting electronic components on the circuit substrate according to any one of claims 1 to 6, After the constituent materials are arranged on the substrate and the electronic component is arranged, the electronic component is bonded to the first terminal and the second terminal using a pressure reflow device.

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