JP5855822B2 - Multiple wiring board - Google Patents

Description

  The present invention relates to a wiring board for mounting electronic components such as a semiconductor element, a crystal oscillator, and a light emitting element, and a multi-piece wiring board in which a wiring board region serving as a wiring board is arranged in at least one of vertical and horizontal directions. It is about.

  Conventionally, wiring boards for mounting electronic components such as semiconductor elements and crystal resonators are made of an insulating substrate made of an electrically insulating material such as an aluminum oxide sintered body, and a metal powder metallization such as tungsten or molybdenum. It is formed by arranging a wiring conductor. And while mounting an electronic component on such a wiring board and electrically connecting each electrode of an electronic component to a corresponding wiring conductor via electrical connection means, such as a solder and a bonding wire, an electronic device Is produced.

  Such wiring boards are becoming smaller in size with the recent demand for thinner and smaller electronic devices. In order to efficiently produce a plurality of wiring boards, a multi-piece wiring board is used. It has been made by dividing. The multi-cavity wiring board is obtained by arranging a plurality of wiring board regions to be a wiring board on a large-area mother board in the vertical and horizontal directions.

  Further, in such a multi-piece wiring board, the above-described wiring conductor is formed in the wiring board region, and a plating wiring electrically connected to the wiring conductor in these wiring board regions is formed. There is a case. In such a case, the plating layer is formed on the exposed surface of the wiring conductor by electroplating by immersing a large number of wiring boards in a plating bath and passing a current through each wiring conductor via the wiring for plating. Adhere.

  A plurality of electronic devices are manufactured at the same time by mounting an electronic component on each wiring board region, electrically connecting the electronic component and the wiring conductor, and then dividing each wiring board region.

  Further, in order to improve the heat dissipation of the electronic device, a wiring board is known in which a heat radiating body having a higher thermal conductivity than the insulating substrate is bonded to the lower surface of the insulating substrate with a bonding material. In such a wiring board, there is a case where a radiator having a size larger than that of an insulating substrate is joined (see, for example, Patent Document 1).

JP 2004-317991 A

However, in the multi-cavity wiring board provided with the plating wiring as described above, after the multi-cavity wiring board is divided, the plating wiring is exposed to the side surface of the insulating substrate. In recent years, there has been a demand for further reduction in the thickness of the wiring board, and the distance between the heat sink bonded to the lower surface of the insulating substrate and the plating wiring exposed on the side surface of the wiring board has become very narrow. For this reason, the plating wiring and the heat dissipating member are joined by ion migration between the plating wiring and the heat dissipating member, the spread of the bonding material, etc., and the wiring conductor and the heat dissipating member are electrically connected via the plating wiring. May be connected. When this occurs, it may become impossible to apply a desired voltage or current to the electronic component, or a plurality of wiring conductors may be short-circuited. For example, when a light-emitting element is used as an electronic component, a desired current cannot be applied to the light-emitting element and light cannot be emitted satisfactorily.

  The present invention has been devised in view of the above-described problems of the prior art, and an object of the present invention is to reduce a short circuit between a plurality of wiring conductors in a wiring board in which a radiator is bonded to the lower surface of an insulating board. An object of the present invention is to provide a wiring board and a multi-piece wiring board capable of efficiently producing a plurality of such wiring boards.

The multi-cavity wiring board according to the present invention includes a mother board in which a plurality of wiring board regions are arranged in at least one of the vertical and horizontal directions, and a first main surface that is arranged on each of the wiring board regions. 1 wiring conductor and 2nd wiring conductor, 3rd wiring conductor which electrically connects said 1st wiring conductors, 4th wiring conductor which electrically connects said 2nd wiring conductors, and each wiring board area | region In a multi-piece wiring board having a heat sink bonded to the lower surface of the wiring board, the heat sink is larger than each wiring board area in a plan view, and a boundary between the wiring board area and the dummy area or between the wiring board areas. A cutout is provided below at least one of the portions where the third wiring conductor or the fourth wiring conductor is disposed at the boundary of the boundary, and a protruding portion from which another adjacent radiator is protruded is disposed in the cutout. That It is an butterfly.

According to the multi- cavity wiring board of the present invention, a plurality of wiring board regions are drawn out and arranged on one main surface in each of the mother board arranged in at least one of the vertical and horizontal directions and the wiring board region. A first wiring conductor and a second wiring conductor; a third wiring conductor that electrically connects the first wiring conductors; a fourth wiring conductor that electrically connects the second wiring conductors; and In a multi-piece wiring board having a heat sink bonded to the lower surface, the heat sink is larger than each wiring board area in a plan view, and is a third boundary between the wiring board area and the dummy area or between the wiring board areas. Since there is a notch below at least one of the portions where the wiring conductor or the fourth wiring conductor is arranged, and the protruding portion from which the other adjacent radiator is protruding is arranged in the notch, Along the wiring board area Before the split, can bond the heat radiator to the mother substrate, by dividing the number joining the heat radiating body-cavity circuit board, the wiring board bonded to the heat radiating body number,
Can be manufactured efficiently.

(A) is a top view which shows an example of embodiment of the wiring board of this invention, (b) is an example of the bottom view of (a), (c) is a side view from the A direction of (a). It is an example. (A) is sectional drawing in the AA of FIG. 1 (a), (b) is a principal part expanded sectional view in the A section of (a). (A) is sectional drawing in the BB line of Fig.1 (a), (b) is a principal part expanded sectional view in the A section of (a). (A) is a top view which shows the other example of embodiment of the wiring board of this invention, (b) is an example of the bottom view of (a), (c) is from the A direction of (a). It is an example of a side view. (A) is a top view which shows the other example of embodiment of the wiring board of this invention, (b) is an example of the bottom view of (a), (c) is from the A direction of (a). It is an example of a side view. (A) is sectional drawing in the AA of FIG. 5 (a), (b) is an example of an internal top view of FIG. 5 (a). (A) is sectional drawing in the BB line of Fig.5 (a), (b) is an example of the internal top view of Fig.5 (a). (A) is a top view which shows the other example of embodiment of the wiring board of this invention, (b) is an example of the bottom view of (a), (c) is from the A direction of (a). It is an example of a side view. (A) is sectional drawing in the AA line of Fig.8 (a), (b) is sectional drawing in the BB line of Fig.8 (a). (A) And (b) is sectional drawing which shows the other example of embodiment of the wiring board of this invention. (A) is a top view which shows an example of embodiment of the multi-piece wiring board of this invention, (b) is an example of a bottom view. (A) is an example of a cross-sectional view taken along line AA in FIG. 11 (a), and (b) is an example of an internal plan view of FIG. 11 (a). (A) is an example of a sectional view taken along line BB in FIG. 11 (a), and (b) is an example of an internal plan view of FIG. 11 (a). (A) is a top view which shows the other example of embodiment of the multi-piece wiring board of this invention, (b) is an example of a bottom view. (A) is another example of the cross-sectional view taken along the line AA in FIG. 14 (a), and (b) is another example of the internal plan view of FIG. 11 (a). (A) is another example of the cross-sectional view taken along the line BB of FIG. 14 (a), and (b) is another example of the internal plan view of FIG. 11 (a).

  The wiring board of the present invention will be described in detail with reference to the accompanying drawings. 1 to 16, 1 is an insulating substrate, 1 a is an edge of the insulating substrate 1, 2 is a first wiring conductor, 3 is a second wiring conductor, 4 is a third wiring conductor, and 4 a is a lead of the third wiring conductor 4. , 5 is a fourth wiring conductor, 5a is a lead-out portion of the fourth wiring conductor 5, 6 is a radiator, 6a is a separation portion, 6b is a notch, 6c is a protruding portion, 7 is a bonding material, 8 is a concave portion, 9 Is a first metal conductor, 10 is a second metal conductor, 11 is a mother board, 11a is a wiring board region, 11b is a dummy region, and 12 is a common conductor.

  1 to 10, the wiring board of the present invention includes an insulating substrate 1, a first wiring conductor 2 and a second wiring conductor 3 drawn out on the upper surface of the insulating substrate 1, and a first wiring conductor. 3, the third wiring conductor 4 connected to the side of the insulating substrate 1, and the fourth wiring conductor 5 connected to the second wiring conductor 3 and drawn to the side of the insulating substrate 1. In the wiring board including the heat dissipating body 6 disposed on the lower surface, the heat dissipating body 6 includes at least one of the lead portion 4a from which the third wiring conductor 4 is drawn and the lead portion 5a from which the fourth wiring conductor 5 is drawn. Below the lead-out portion, the insulating substrate 1 is separated from the edge 1a. Since it is such a configuration, the distance between at least one lead portion on the side surface of the insulating substrate 1 and the radiator 6 can be increased by the spacing portion 6a without increasing the thickness of the wiring substrate. The spread of the material suppresses a short circuit between the third wiring conductor 4 and the radiator 6 and between the fourth wiring conductor 5 and the radiator 6 and the first wiring conductor 2 and the second wiring conductor 3 are short-circuited. Can be suppressed.

In the example shown in FIGS. 1 to 10, the wiring board is a rectangular insulating substrate 1, a first wiring conductor 2, a second wiring conductor 3, and a third wiring connected to the first wiring conductor 2. A conductor 4, a fourth wiring conductor 5 connected to the second wiring conductor, and a radiator 6 bonded to the lower surface of the insulating substrate 1 via a bonding material 7 and having a size larger than that of the insulating substrate 1 in plan view; It has.

  1 to 4, the radiator 6 is separated from the edge 1 a of the insulating substrate 1 below the lead portion 5 a from which the fourth wiring conductor 5 is drawn. In the example shown in FIGS. 5 to 9 and FIG. 10B, the radiator 6 is separated from the edge 1a of the insulating substrate 1 below the lead portion 4a from which the third wiring conductor 4 is drawn. In the example shown in FIG. 10 (a), the heat dissipating body 6 extends from the edge 1a of the insulating substrate 1 below the lead portion 4a from which the third wiring conductor 4 is drawn and the lead portion 5a from which the fourth wiring conductor 5 is drawn. It is separated.

  The insulating substrate 1 is made of ceramics such as an aluminum oxide sintered body (alumina ceramic), an aluminum nitride sintered body, a mullite sintered body, or a glass ceramic sintered body.

  If the insulating substrate 1 is made of, for example, an aluminum oxide sintered body, an appropriate organic binder and solvent are added to and mixed with raw material powders such as aluminum oxide, silicon oxide, magnesium oxide and calcium oxide to form a slurry. Then, this is formed into a sheet shape by the doctor blade method or the calender roll method to obtain a ceramic green sheet. After that, the ceramic green sheet is subjected to appropriate punching processing, and a plurality of these are laminated to obtain a high temperature (about 1600 Manufactured by baking at a temperature of ° C.

  The insulating substrate 1 may have a concave portion 8 on the upper surface as in the examples shown in FIGS. 1 to 4 and FIGS. 8 to 10. Such recesses 8 are formed by forming through holes to be the recesses 8 in a plurality of ceramic green sheets by laser processing or punching with a mold on the ceramic green sheets, and forming these through holes in the ceramic green sheets. It can be formed by laminating the ceramic green sheets. In addition, when the thickness of the insulating substrate 1 is thin, it is preferable that the through hole for the concave portion 8 is formed by laser processing or punching with a mold after the ceramic green sheets are laminated, because it can be processed with high accuracy.

  When the concave portion 8 is a concave portion for mounting a light emitting element, the angle θ formed by the inner side surface of the concave portion 8 and the bottom surface of the concave portion 8 is an obtuse angle, as in the example shown in FIGS. 110 degrees to 145 degrees is particularly preferable. When the angle θ is in such a range, it is easy to stably and efficiently form the inner surface of the through hole that becomes the recess 8 by punching, and the light emitting device using this wiring board can be easily downsized. In addition, the light emitted from the light emitting element can be emitted well toward the outside. The concave portion 8 having such an inner surface of the angle θ is formed by punching the ceramic green sheet using a punching die in which the clearance between the punch diameter and the die hole diameter is set large. That is, by setting the clearance of the diameter of the die hole larger than the diameter of the punch of the punching die, when the ceramic green sheet is punched from one main surface side to the other main surface side, the green sheet It is sheared from the edge of the contact surface with the punch toward the edge of the contact surface with the die hole, and the diameter of the through hole is formed to spread from one main surface side to the other main surface side. At this time, the angle of the inner surface of the through hole formed in the ceramic green sheet can be adjusted by setting the clearance between the diameter of the punch and the diameter of the die hole according to the thickness of the ceramic green sheet. Such a punching method is highly productive because the angle θ formed by the inner surface of the recess 8 and the bottom surface of the recess 8 can be set to a desired angle only by punching.

  In addition, after forming a through hole having an angle θ of about 90 degrees by processing with a punching die having a small clearance between the diameter of the punch and the diameter of the die, a truncated cone shape or a truncated pyramid shape is formed on the inner surface of the through hole. A through-hole having an angle θ extending from one main surface side to the other main surface side as described above may be formed by pressing the mold. In such a case, the angle θ formed by the inner surface of the recess 8 and the bottom surface of the recess 8 can be adjusted with higher accuracy.

  In the example shown in FIGS. 1 to 10, one end of each of the first wiring conductor 2 and the second wiring conductor 3 is led out to the upper surface of the insulating substrate 1, and each of the first wiring conductor 2 and the second wiring conductor 3 is 1. It is provided one by one. The first wiring conductor 2 and the second wiring conductor 3 are connected to the electrodes of the electronic component mounted on the upper surface of the insulating substrate 1 or the bottom surface of the recess 8 and are also connected to the wiring of the external electric circuit board. Is. Further, the first wiring conductor 2 and the second wiring conductor 3 may be ones whose ends are drawn out to a plurality of positions on the upper surface as in the examples shown in FIGS. 4 and 8. The plurality of first wiring conductors 2 and second wiring conductors 3 are connected to the wiring of the external electric circuit board, respectively.

One end of the third wiring conductor 4 is electrically connected to the first wiring conductor 2, and the other end is drawn out to the side surface of the insulating substrate 1. The third wiring conductor 4 is used as a wiring for passing a current when a plating layer is deposited on the exposed surface of the first wiring conductor 2 by electrolytic plating. The fourth wiring conductor 5 has one end electrically connected to the second wiring conductor 3 and the other end drawn to the side surface of the insulating substrate 1. The fourth wiring conductor 5 is used as a wiring for passing a current when a plating layer is deposited on the exposed surface of the second wiring conductor 3 by electrolytic plating. Further, when the third wiring conductor 4 and the fourth wiring conductor 5 are drawn out to the same side surface of the insulating substrate 1, the distance between the leading portion 4 a of the third wiring conductor 4 and the leading portion 5 a of the fourth wiring conductor 5 is In order to suppress ion migration between the lead portion 4a of the third wiring conductor 4 and the lead portion 5a of the fourth wiring conductor 5, the thickness is preferably set to 1.0 mm or more. Further, as in the example shown in FIGS. 4 and 5, the lead portions 4a of the plurality of third wiring conductors 4 and the lead portions 5a of the fourth wiring conductors 5 drawn to the same side surface are arranged at different heights. Thus, the distance between the lead portion 4a of the third wiring conductor 4 and the lead portion 5a of the fourth wiring conductor 5 may be increased. In order to arrange the lead-out part 4a of the third wiring conductor 4 and the lead-out part 5a of the fourth wiring conductor 5 at different heights, the third wiring conductor 4 and the fourth wiring conductor 5 should be arranged between different insulating layers. Good.

  The first wiring conductor 2, the second wiring conductor 3, the third wiring conductor 4 and the fourth wiring conductor 5 are made of tungsten (W), molybdenum (Mo), manganese (Mn), silver (Ag) or copper ( It consists of metallization of metal powder such as Cu). For example, when the insulating substrate 1 is made of an aluminum oxide sintered body, a conductive paste obtained by adding and mixing an appropriate organic binder and solvent to a refractory metal powder such as W, Mo or Mn is used as the insulating substrate. The ceramic green sheet to be 1 is preliminarily printed and applied in a predetermined pattern by a screen printing method. Thereafter, the ceramic green sheet to be the insulating substrate 1 and the conductor paste printed and applied in a predetermined pattern are fired at the same time, so that the first wiring conductor 2, the second wiring conductor 3, and the third wiring are formed at predetermined positions on the insulating substrate 1. The wiring conductor 4 and the fourth wiring conductor 5 are deposited. When the first wiring conductor 2, the second wiring conductor 3, the third wiring conductor 4 and the fourth wiring conductor 5 are through conductors, the first wiring conductor 2, the second wiring conductor 3, and the third wiring conductor formed on the surface. Before forming the conductor paste pattern to be the wiring conductor 4 and the fourth wiring conductor 5, a through hole is formed in the green sheet by punching by a die or punching or laser processing, and the conductor paste is printed in this through hole by a printing method. It is formed by filling.

  A plating layer is applied to the exposed surfaces of the first wiring conductor 2 and the second wiring conductor 3 by electrolytic plating. The plating layer is made of a metal having excellent corrosion resistance such as nickel, gold, or silver, and connectivity with a connecting member. For example, a nickel plating layer having a thickness of about 1 to 10 μm and a gold plating layer having a thickness of about 0.1 to 3 μm Alternatively, a nickel plating layer having a thickness of about 1 to 10 μm and a silver plating layer having a thickness of about 0.1 to 1 μm are sequentially deposited. Thus, corrosion of the first wiring conductor 2 and the second wiring conductor 3 can be effectively suppressed, and the electronic component and the first wiring conductor 2 or the second wiring conductor 3 can be fixed or the first wiring conductor 2 or The bonding between the second wiring conductor 3 and a connecting member such as a bonding wire, the bonding between the external terminal and the wiring conductor of the external circuit board, and the bonding between the radiator 6 and the conductor of the external circuit board can be strengthened.

  Further, the radiator 6 is joined to the lower surface of the insulating substrate 1. The radiator 6 can be made of a material having higher thermal conductivity than the insulating substrate 1, for example, a metal material such as copper (Cu), copper-tungsten (Cu—W), or aluminum (Al). For example, when the insulating substrate 1 is an aluminum oxide sintered body, it is mounted on the insulating substrate 1 by using a material having a higher thermal conductivity than the insulating substrate 1 as the heat radiating member 6 using Cu as the radiator 6. When the heat generated in the electronic component is radiated well through the heat radiating body 6, a wiring board having excellent heat dissipation can be obtained. Moreover, the heat dissipation of the light emitting device can be enhanced by bonding the heat radiator 6 to the conductor of the external circuit board.

  The radiator 6 is joined to the lower surface of the insulating substrate 1 by brazing via a joining material 7 such as a brazing material made of silver-copper alloy or the like. In addition, when brazing via the bonding material 7 such as a brazing material, a bonding metal layer may be formed on the lower surface of the insulating substrate 1. In addition, if an active metal brazing material or a resin material in which an active metal such as Ti is added to the brazing material is used, the heat radiating body 6 can be joined to the base body 1 only through the brazing material or the resin material. In addition, when the resin material which added and mixed the brazing material or the metal material with high heat conductivity as the joining material 7 is used, it can be set as the wiring board excellent in heat dissipation.

The radiator 6 is spaced apart from the edge 1a of the insulating substrate 1 below at least one of the lead portion 4a from which the third wiring conductor 4 is drawn and the lead portion 5a from which the fourth wiring conductor 5 is drawn. A portion 6a is provided. The separation part 6a is formed by the fourth wiring part 4a and the fourth wiring part 4a from which the third wiring conductor 4 is drawn out due to ion migration occurring between the third wiring conductor 4 and the fourth wiring conductor 5 and the heat radiating body 6 and the spread of the bonding material 7. This is to prevent a short circuit between the lead portion 5a from which the wiring conductor 5 is drawn. The length of the lead portion 4a from which the third wiring conductor 4 is drawn out and the heat dissipating body 6 and the length of the lead portion 5a from which the fourth wiring conductor 5 is drawn out and the heat dissipating member 6 should be 1.0 mm or more. preferable. For example, if the bonding material 7 is a conductive material, the total length of L1 and L2 in the example shown in FIG. 3B is 1.0 mm.
That is all you need. Further, when the bonding material 7 is an insulating material, the total length of L1, L2, and L3 in the example shown in FIG.

  Further, as shown in FIGS. 1 to 4, 8, and 9, the spacing portion 6 a may be formed in a notch shape in the heat radiating body 6, or FIGS. 5 to 7 and 10 (a). ) May be formed by providing a through hole in the radiator 6. In such a case, there is no heat radiating body 6 below at least one of the lead portion 4a of the third wiring conductor 4 and the lead portion 5a of the fourth wiring conductor 5, and the spread of the bonding material 7 is suppressed. This is effective for suppressing a short circuit between the third wiring conductor 4 and the fourth wiring conductor 5.

  Further, as in the example shown in FIG. 10B, a recess is formed on the upper surface of the radiator 6 from the center side of the insulating substrate 1 to the edge of the radiator 6 in a sectional view rather than the edge 1a of the insulating substrate 1. The separation portion 6a may be formed, or a region where the bonding material 7 is not disposed between the insulating substrate 1 and the radiator 6 is formed on the edge 1a of the insulating substrate 1, and the radiator 6 is connected to the insulating substrate. It may be separated from one edge 1a. In such a case, the radiator 6 can be made larger, which is effective in improving the heat dissipation.

  Further, as shown in the example shown in FIGS. 1 to 10, the spacing portion 6 a of the radiator 6 is drawn out to the upper surface of the insulating substrate 1 and connected to the wiring of the external electric circuit board and the second wiring conductor 2 and the second wiring conductor 2. If the wiring conductor 3 is not overlapped in plan view, the radiator 6 is disposed in a portion overlapping the first wiring conductor 2 and the second wiring conductor 3 in plan view. When the first wiring conductor 2 and the second wiring conductor 3 of the wiring board are pressed and bonded, the first wiring conductor 2 and the second wiring conductor 3 can be pressed and bonded well.

  Further, when the lead portion 4a of the third wiring conductor 4 and the lead portion 5a of the fourth wiring conductor 5 are drawn to different heights, the first wiring conductor as in the example shown in FIGS. The second or third wiring conductor 4 and the second wiring conductor 3 or the fourth wiring conductor 5 may be formed wide within the insulating substrate 1. As a result, when a light emitting element is mounted as an electronic component, the region where the wiring conductor made of metal is arranged is widened inside the insulating substrate 1 to improve the heat dissipation of the light emitting device, and toward the lower surface of the insulating substrate 1. Can prevent light leakage. Further, the resistance of the first wiring conductor 2 and the second wiring conductor 3 can be reduced. Further, as in the example shown in FIGS. 6 and 7, the upper surface of the insulating substrate 1 and the first wiring conductors 2 formed inside or the second wiring conductors 3 are connected by a plurality of through conductors. The heat dissipation of the wiring board can be improved.

  Further, if the insulating substrate 1 has the concave portion 8 and a light emitting element is mounted as an electronic component, the light emitted from the light emitting element on the inner wall surface of the concave portion 8 as in the examples shown in FIGS. A reflective layer for reflecting the light may be provided. The reflective layer is formed of, for example, a first metal conductor 9 formed on the inner wall surface of the recess 8 and a plating layer deposited on the first metal conductor 9. The first metal conductor 9 is provided with a second metal conductor 10 having one end electrically connected to the first metal conductor 9 and the other end drawn to the side surface of the insulating substrate 1. The second metal conductor 10 is used as a wiring for flowing a current when a plating layer is deposited on the exposed surface of the electrically connected first metal conductor 9 by an electrolytic plating method.

  The first metal conductor 9 and the second metal conductor 10 are formed in the same manner as the first wiring conductor 2, the second wiring conductor 3, the third wiring conductor 4, and the fourth wiring conductor 5. Is formed on the substrate. Thereby, a flat reflective film can be formed on the inner wall surface of the recess 8. The metal paste may be the same as the above-mentioned conductor paste, or may be one in which the type and amount of the organic binder or solvent are changed in consideration of printability. The plating layer deposited on the surface of the first metal conductor 9 is, for example, the same as the plating layer deposited on the exposed surfaces of the first wiring conductor 2 and the second wiring conductor 3. it can.

  In addition, the gold plating layer is superior to the connection member and the wiring conductor of the external circuit board in comparison with the silver plating layer, and the silver plating layer has a higher reflectance to light than the gold plating layer. Therefore, in the case where a light emitting element is mounted as an electronic component, for example, a silver plating layer is deposited on the surface of the first metal conductor 9 and the surfaces of the first wiring conductor 2 and the second wiring conductor 3 are applied. A gold plating layer may be deposited. Further, the outermost surfaces of the first wiring conductor 2 and the second wiring conductor 3 and the first metal conductor 9 can be used as an alloy plating layer of silver and gold, for example, an alloy plating layer of a complete solid solution of silver and gold. I do not care. In this case, since there is no single silver particle on the surface of the alloy plating layer, the surface of the alloy plating layer is not easily sulfided even in a sulfurized atmosphere, and it is easy to maintain the reflection characteristics, and the wiring board has excellent reliability. And can.

  Further, as in the example shown in FIG. 10A, the first metal conductor 9 is formed on the entire bottom surface and side surface of the recess 8, and the first wiring conductor 2 and the second wiring conductor 3 are insulated around the recess 8. The first wiring conductor 2 may be formed on the entire bottom surface of the recess 8 and the entire side surface of the recess 8 and insulated at one end as in the example shown in FIG. The upper surface of the substrate 1 may be pulled out. Since it is not necessary to provide a plating wiring electrically connected to the metal layer serving as the reflection layer on the inner surface of the recess 8, it is effective for making the wiring board thinner.

  When the second metal conductor 10 is provided and the same plating layer is applied to the surface of the first wiring conductor 2 and the surface of the first metal conductor 9, the third wiring conductor 4 and the second metal conductor 10 May be electrically connected.

As described above, since the wiring board on which the light emitting element is mounted has a reflection layer that reflects light from the light emitting element on the entire inner surface of the concave portion 8, when the depth of the concave portion 8 is deeper than the height of the light emitting element, The luminance when the light emitting device is obtained can be increased. In the case of FIG. 10A, it can be suitably used for a 2-wire type light emitting element, and in the case of FIG. 10B, it can be suitably used for a 1 wire type light emitting element.

  Electronic components mounted on the wiring board are semiconductor elements such as IC chips and LSI chips, light emitting elements, piezoelectric elements such as crystal vibrators and piezoelectric vibrators, and various sensors. For example, when the electronic component is a flip-chip type semiconductor element, the semiconductor element is an electrode of the semiconductor element via a bonding material such as a solder bump, a gold bump, or a conductive resin (anisotropic conductive resin). And the first wiring conductor 2 are mounted on the wiring board by being electrically and mechanically connected. Further, for example, when the electronic component is a wire bonding type semiconductor element, the semiconductor element is fixed to the electronic component mounting region with a bonding material, and then the electrode of the semiconductor element and the first wiring conductor via the bonding wire. 2 is electrically connected to the wiring board.

  Next, the multi-piece wiring board of the present invention will be described in detail with reference to the accompanying drawings. The multi-piece wiring board of the present invention is for manufacturing the above-described wiring board of the present invention.

  As shown in the examples shown in FIGS. 11 to 16, the multi-piece wiring board of the present invention includes a mother board 11 in which a plurality of wiring board regions 11a are arranged in at least one of vertical and horizontal directions, and a wiring board region 11a. , The first wiring conductor 2 and the second wiring conductor 3 arranged so as to be drawn out to one main surface, the third wiring conductor 4 that electrically connects the first wiring conductors 2, and the second wiring conductor 3. In a multi-piece wiring board having a fourth wiring conductor 5 that electrically connects each other and a radiator 6 joined to the lower surface of the wiring board area 11a, the radiator 6 includes the wiring board area 11a and the dummy area 11b. Or a portion where the third wiring conductor 4 or the fourth wiring conductor 5 is disposed at the boundary between the wiring board regions 11a, and a protrusion in which the adjacent radiator 6 protrudes into the notch 6b. The part 6c is arranged. With the above configuration, before dividing the mother board along the wiring board region, the heat sink can be joined in the mother board, and the wiring with the heat sink joined by dividing the multi-piece wiring board joined with the heat sink A large number of substrates can be manufactured efficiently.

  In the example shown in FIG. 11 to FIG. 16, the multi-piece wiring board has nine wiring board regions 11a that are to be wiring boards after division, that is, three vertically and three horizontally. The wiring board region 11a may be arranged in a plurality of at least one of the vertical and horizontal directions, and may be arranged in a larger number. Such an arrangement of the wiring board region 11a includes the size of the mother board 11 and the wiring board region 11a, the electronic components mounted on the wiring board region 11a, the first wiring conductor 2, the second wiring conductor 3, and the third wiring conductor. 4 and the fourth wiring conductor 5 are set in accordance with the arrangement and the like.

  If the base substrate 11 is made of an aluminum oxide sintered body, for example, an appropriate organic binder, solvent, plasticizer and dispersion for ceramic raw material powders such as aluminum oxide, silicon oxide, magnesium oxide and calcium oxide The ceramic slurry obtained by adding and mixing the agent and the like is formed into a sheet shape by using a conventionally known sheet forming method such as a doctor blade method to obtain a ceramic green sheet, and then the ceramic green sheet is appropriately punched. A plurality of layers are laminated as necessary to produce a formed body to be the mother substrate 1 and fired at a temperature of about 1500 ° C. to 1800 ° C. to produce a plurality of insulating layers. The

In the example shown in FIGS. 11 to 15, the mother board 11 has a dummy area 11b around a plurality of wiring board areas 11a arranged in at least one of the vertical and horizontal directions (the outer periphery of the mother board 11). doing. The dummy area 11b is an area for facilitating the manufacture and transfer of the multi-piece wiring board. When the dummy area 11b is used to form the generation structure to be the mother board 11 or the multi-piece wiring board and carry it. Positioning, fixing, etc. can be performed. Moreover, you may have the dummy area | region 11b around each of the some wiring board area | region 1a arranged at least one of the vertical and horizontal.

  The dummy region 11b is also used as a region where the third wiring conductor 4, the fourth wiring conductor 5, and the second metal conductor 10 are formed. In the dummy region 11b, the third wiring conductors 4, the fourth wiring conductors 5, or the third wiring conductor 4 and the fourth wiring conductor 5 may be electrically connected. The common conductor 12 is made wider than the width of the wiring board region 11a and is manufactured in the same manner as the third wiring conductor 4 and the fourth wiring conductor 5. If it is formed in a frame shape in the dummy region 11b provided in the outer peripheral portion) or in a lattice shape in the dummy region 11b provided in the periphery of each wiring substrate region 1a, the number of each wiring substrate region 1a is changed. Variations in the thickness of the plating layers deposited on the first wiring conductor 2 and the second wiring conductor 3 can be reduced.

  The radiator 6 is joined to the lower surface of the mother board 1 for each wiring board area 11a, and the third wiring conductor 4 or the fourth wiring 4 at the boundary between the wiring board area 11a and the dummy area 11b or between the wiring board areas 11a. The portion where the wiring conductor 5 is disposed has a notch 6b, and a protrusion 6c from which the adjacent radiator 6 protrudes is disposed in the notch 6b.

At least one of the third wiring conductor 4 and the fourth wiring conductor 5 is a wiring at a portion where notches 6b of the radiator 6 are formed at both ends as in the examples shown in FIGS. 12, 13, 15, and 16. It is arranged so as to straddle the outer edge of the substrate region 11a. Thereby, when divided into individual wiring boards, at least one of the lead part 4 a of the third wiring conductor 4 and the lead part 5 a of the fourth wiring conductor 5 is separated from the heat radiator 6 at the edge 1 a of the insulating substrate 1. .

The third wiring conductor 4 electrically connects the first wiring conductors 2 of the adjacent wiring board regions 1a as in the example shown in FIGS. 12 and 13, and the fourth wiring conductor 5 is the adjacent wiring board. The second wiring conductors 3 in the region 1a are electrically connected. Further, as shown in the examples of FIGS. 15 and 16, the first wiring conductor 2 and the second wiring conductor 3 of the adjacent wiring board region 1a are alternately inverted in a plan view, and the third wiring conductor is arranged. 4, the first wiring conductors 2 in the adjacent wiring board region 1a may be electrically connected to each other, and the fourth wiring conductor 5 may be electrically connected to the second wiring conductors 3 in the adjacent wiring board region 1a. Absent. In this case, it becomes easy to arrange one of the third wiring conductor 4 and the fourth wiring conductor 5 so as to straddle the outer edge of the wiring board region 11a where the cutout 6b is formed. In such a case, as shown in the examples of FIGS. 14 to 16, the adjacent wiring board regions 1a may be alternately inverted in a plan view.
When the plating layers deposited on the exposed surfaces of the first wiring conductor 2 and the second wiring conductor 3 are the same, the third wiring conductor 4 and the fourth wiring conductor as in the examples shown in FIGS. 5 may be electrically connected, and the first wiring conductor 2 and the second wiring conductor 3 may be alternately electrically connected in the adjacent wiring board regions 11a. In this case, it becomes easy to arrange one of the third wiring conductor 4 and the fourth wiring conductor 5 so as to straddle the outer edge of the wiring board region 11a where the cutout 6b is formed.

  Moreover, although the 3rd wiring conductor 4 and the 4th wiring conductor 5 are extended in the same direction, if it is extended in the direction which cross | intersect by planar view, either of the 3rd wiring conductor 4 and the 4th wiring conductor 5 will be carried out. It becomes easy to dispose one of them over the outer edge of the wiring board region 11a where the notch 6b is formed, and the electronic component is mounted on each wiring board region 11a and then provided on the outer periphery of the mother board 11. By removing the dummy region 11b, the electrical connection state between the first wiring conductor 2 and the second wiring conductor 3 can be confirmed for each row and column of each wiring board region 11a.

Then, by dividing the multi-piece wiring board as described above along the outer edge of each wiring board region 11a, the wiring boards as shown in the examples shown in FIGS. 1 to 10 can be obtained. An electronic device can be obtained by mounting electronic components on the upper surface of the wiring board. Alternatively, after electronic components are mounted on the upper surface of each wiring board region 11a, they may be divided along the outer edge of each wiring board region 11a.

  The mother board 11 may be formed with a groove that overlaps the protrusion along the outer edge of the wiring board region 11a that overlaps the protrusion 6 in plan view. Thereby, the joining material 7 can be joined to the side surface of the groove, and the mother board 11 and the radiator 6 can be firmly joined. Moreover, since the groove is set to a depth at which the bonding material 7 does not reach the bottom, when dividing the multi-cavity wiring board along the outer edge of each wiring board region 11a, the bonding material 7 is not divided at the time of division. It can be divided well into individual wiring boards. Such a groove can be formed into, for example, a V-shaped, quadrangular or trapezoidal groove in a sectional view. In the case of a rectangular or trapezoidal groove, a dummy region 11b having a width equal to or larger than the width of the groove may be formed around each wiring board region 11a.

  A method of dividing the mother substrate 11 into a plurality of insulating substrates 1 is a method in which a dividing groove is formed in the outer edge of the wiring substrate region 11a of the mother substrate 11, and the substrate is bent along the dividing groove, or slicing is performed. For example, a method of cutting along the outer edge of the wiring board region 11a can be used. The dividing grooves can be formed by pressing the cutter blade against the generated shape for the mother substrate 11, cutting it with a slicing device smaller than the thickness of the generated shape, or cutting it after the baking with a slicing device smaller than the thickness of the mother substrate 11.

  The present invention is not limited to the above-described embodiments, and various modifications can be made. For example, in the example shown in FIGS. 1 to 10, a wiring board in which one insulating substrate 1 is bonded to one radiator 4 is shown, but a plurality of insulating substrates 1 are bonded to one radiator 4. It may be a wiring board.

  In the example shown in FIGS. 1 to 10, the insulating substrate 1 has a rectangular shape in plan view, but a hole having a bottom portion opened on the upper surface side is formed in a semicircular shape or a long side on the side surface of the insulating substrate 1. A circular hole or a fan-shaped hole may be provided at the corner of the insulating substrate 1, and the third wiring conductor 4 or the fourth wiring conductor 5 may be provided on the inner peripheral surface of the hole. In this case, the heat dissipating body 6 may be provided with a spacing portion 6a such as a notch larger than the hole in plan view.

  Moreover, in the example shown in FIGS. 1-10, although the insulating substrate 1 is rectangular shape and the heat radiator 6 is a rectangular shape provided with the separation part 6a, the heat radiator 6 is equipped with the separation part 6a by planar view. An elliptical shape, an oval shape, or a polygonal shape may be used.

  Moreover, although the wiring board of the example shown in FIGS. 1-10 is provided with the 1st wiring conductor 2 and the 2nd wiring conductor 3, according to the electronic component mounted in a wiring board and a small electronic component, More wiring conductors may be provided. In this case, the spacing portion 6a of the heat radiating body 6 may be provided in accordance with the respective drawer portions.

  In the example shown in FIGS. 1 to 10, the third wiring conductor 4 and the fourth wiring conductor 5 are led out to two opposite side surfaces of the insulating substrate 1, but are led out to other side surfaces of the insulating substrate 1. It doesn't matter.

DESCRIPTION OF SYMBOLS 1 ... Insulating substrate 1a ... Edge 2 of an insulating substrate ... 1st wiring conductor 3 ... 2nd wiring conductor 4 ... 3rd wiring conductor 4a ... 3rd wiring conductor 4th wiring conductor 5a ... 3rd wiring conductor drawing part 6 ... Radiator 7 ... Bonding material 8 ... Recess 9 ... 1st Metal conductor
10 ... Second metal conductor
11 ... Mother board
11a: Wiring board area
11b ... dummy area
12 ... Common conductor

Claims (1)

  A mother board in which a plurality of wiring board regions are arranged in at least one of the vertical and horizontal directions; a first wiring conductor and a second wiring conductor arranged to be drawn out on one main surface of each of the wiring board regions; A third wiring conductor that electrically connects the first wiring conductors; a fourth wiring conductor that electrically connects the second wiring conductors; and a radiator that is bonded to the lower surface of each wiring board region. In the multi-cavity wiring board having, the heat dissipation body is larger than each wiring board area in a plan view, and the third wiring conductor or the boundary between the wiring board area and the dummy area or between the wiring board areas A multi-cavity characterized in that it has a notch below at least one of the portions where the fourth wiring conductor is disposed, and a projecting portion from which another adjacent heat radiator projects is disposed in the notch. Wiring board.

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