JP5052398B2 - Multi-cavity wiring board, wiring board and electronic device - Google Patents

Description

  In the present invention, a plurality of wiring board regions, each of which is a wiring board for mounting electronic components, are arranged vertically and horizontally in the central portion of the mother board, and a plurality of dividing grooves are formed at the boundary of the wiring board area. The present invention relates to a wiring board, a wiring board obtained by dividing the wiring board, and an electronic device in which electronic components are mounted on the wiring board.

  Conventionally, wiring boards for mounting electronic components such as semiconductor elements and crystal resonators are made of metal powder metallization such as tungsten or molybdenum on the surface of an insulating base made of an electrically insulating material such as an aluminum oxide sintered body. It is formed by arranging a wiring conductor made of

  Such a wiring board has been reduced in size in accordance with the recent demand for miniaturization of electronic devices. In order to efficiently manufacture a plurality of wiring boards, a plan view is shown in FIG. Such a so-called multi-piece wiring board is manufactured by dividing it. In the multi-cavity wiring board, a plurality of wiring board regions 1a serving as wiring boards are arranged vertically and horizontally in the center of a large-area mother board 1, and divided grooves 2 (2x, 2y) for dividing each wiring board area 1a. Are formed vertically and horizontally. A plurality of wiring boards can be obtained by dividing the mother board 1 along the dividing grooves 2 (2x, 2y). In addition, in order to efficiently mount electronic components on the wiring board, the electronic components are mounted on each wiring board region 1a of the multi-piece wiring board and then divided.

In such a multi-piece wiring board, the mother board 1 can be easily divided well along the dividing grooves 2 (2x, 2y), and the whole mother board 1 is inadvertently cracked during handling. In order to suppress this, for example, as shown in a cross-sectional view in FIG. 8B, the depth of the dividing groove 2x is changed stepwise from the end side of the mother board 1 toward the center side. It is known (see Patent Document 1).
JP 2004-119490 A

  However, when the depth of the dividing groove 2x changes stepwise, that is, when the dividing groove 2x has discontinuously different portions, the mother substrate 1 is divided along the dividing grooves 2 (2x, 2y). Further, the divided groove surrounded by a broken-line circle in the cross-sectional view showing an enlarged portion A of FIG. 8B of the portion where the depth of the divided groove 2x is discontinuously different, shown in FIG. 8C. Cracks starting from the end (corner) of the bottom of the deeper 2x depth also propagate in directions other than the direction of the other main surface from the bottom of the dividing groove 2x, and the wiring substrate obtained by dividing It had the problem of causing large burrs and chips. When there are large burrs or chips on the wiring board, electronic components are mounted on the wiring board based on the outer edge of the wiring board, or on the external electric circuit board based on the outer edge of the electronic device on which the electronic components are mounted on the wiring board. When an electronic device is mounted, there is a problem that the accuracy of the mounting position is lowered.

  The present invention has been devised in view of the above-described problems of the prior art, and its purpose is to occur in a wiring board when dividing a multi-piece wiring board having discontinuously different depths of dividing grooves. An object of the present invention is to provide a multi-cavity wiring board that can reduce burrs and chips.

The multi-cavity wiring board of the present invention is the multi-cavity wiring board in which a plurality of wiring board regions are formed on one main surface of a mother board in which a plurality of wiring board regions are arranged vertically and horizontally, and a dividing groove is formed at a boundary of the wiring board region The dividing groove has a portion where the depth from one main surface is discontinuously different, and the portion where the depth of the dividing groove is discontinuously different from the bottom end of the portion where the depth is deep in one dividing groove A hole reaching the other main surface is formed.

  Further, the multi-piece wiring board of the present invention is characterized in that, in the above configuration, the opening width of the dividing groove on one main surface of the mother board is uniform in the length direction.

  The wiring board of the present invention is characterized in that the multi-piece wiring board having the above configuration is divided along the dividing groove.

  The electronic device of the present invention is characterized in that an electronic component is mounted on the wiring board having the above-described configuration.

According to the multi-cavity wiring board of the present invention, in the portions where the depths of the dividing grooves are discontinuously different ,
Since a hole is formed from the bottom edge of the part where the depth is deep in the dividing groove to the other main surface, there are no corners that are the origin of cracks that cause burrs and chips, so there are many When dividing the wiring board along the dividing groove, the mother board can be divided by favorably progressing cracks from the bottom of the deep part of the dividing groove toward the other main surface side, Burrs and chips generated on each wiring board can be reduced.

  Further, according to the multi-cavity wiring board of the present invention, in the above configuration, when the opening width of the dividing groove on the one main surface of the mother board is uniform in the length direction, the outer edge on the one main surface of each wiring board region Therefore, the outer edge of each wiring board area can be recognized well by an image recognition device, etc., and the mounting of electronic components on each wiring board area can be improved with reference to the outer edge of each wiring board area. It becomes a multi-piece wiring board that can be performed.

  Further, according to the wiring board of the present invention, since the multi-piece wiring board having the above configuration is divided along the dividing groove, there is no large burr or chip on the outer edge portion of the wiring board. The outer edge of the board can be well recognized by an image recognition device or the like, and the mounting of electronic components on the wiring board can be performed with good positional accuracy with reference to the outer edge of the wiring board.

  Further, according to the electronic device of the present invention, since the electronic component is mounted on the wiring board having the above-described configuration, the outer edge of the electronic device is free from large burrs and chips. Therefore, the electronic device can be well recognized with respect to the outer edge of the electronic device with reference to the outer edge of the electronic device.

  A multi-piece wiring board of the present invention will be described with reference to the accompanying drawings.

  FIG. 1A is a plan view showing an example of an embodiment of a multi-cavity wiring board according to the present invention, and FIG. 1B is a cross-sectional view showing a cross section taken along line AA of FIG. FIG.1 (c) is sectional drawing which shows the BB line | wire cross section of Fig.1 (a). 2A is an enlarged plan view showing an A part of FIG. 1A, and FIG. 2B is an enlarged sectional view showing an A part of FIG. 1C. is there. 1 and 2, 1 is a mother board, 1a is a wiring board region, 2 (2x, 2y) is a dividing groove, and 3 is a hole. Although not shown in these drawings, wiring conductors are formed on the surface and inside of each wiring board region 1a.

  In the example shown in FIG. 1A, a total of 64 wiring board regions 1a are arranged on the mother board 1 in the vertical and horizontal directions, and the dividing grooves 2y in the vertical direction and the horizontal dividing grooves 2y are arranged at the boundaries of the wiring board regions 1a. A dividing groove 2 composed of a dividing groove 2x in the direction is formed. The dividing groove 2 includes both the vertical dividing groove 2y and the horizontal dividing groove 2x. The dividing groove 2 has an area from the end of the dividing groove 2 to the first wiring board area 1a from the outer edge of the mother board 1. On the other hand, the depth d2 from the main surface is deeper than the depth d1 of the inner region.

  As shown in FIGS. 1 and 2, the multi-cavity wiring board according to the present invention is provided on one main surface of a mother board 1 in which a plurality of wiring board areas 1 a are arranged vertically and horizontally on the boundary of the wiring board area 1. In the multi-piece wiring board in which the dividing groove 2 is formed, the dividing groove 2 has a portion where the depth from the one main surface is discontinuously different, and the depth of the dividing groove 2 is changed to a portion where the depth is discontinuously different. A hole 3 is formed from the bottom end of the deeper groove to the other main surface.

  Since such a configuration eliminates the corners that are the starting points of cracks that cause burrs and chips, when dividing the multi-cavity wiring board along the divided grooves 2, The mother substrate 1 can be divided by favorably progressing cracks from the deeper bottom toward the other main surface, and burrs and chips generated on each wiring substrate can be reduced.

  As an example in which the dividing groove 2 has a portion in which the depth from the one main surface is discontinuously different, there are also examples as shown in FIGS. 3 and 4. FIG. 3A is a plan view showing another example of the embodiment of the multi-cavity wiring board according to the present invention, and FIG. 3B shows a cross section taken along the line AA of FIG. FIG. 3C is a cross-sectional view, and FIG. 3C is a perspective view of a wiring board obtained by dividing the multi-cavity wiring board of FIG. 4A is an enlarged plan view showing an A part of FIG. 3A, and FIG. 4B is an enlarged sectional view showing an A part of FIG. 3B. is there. 3 and 4, 1b is a wiring board obtained by dividing the mother board, 4 is a recess, 4a is a notch, and the other reference numerals are the same as those in FIGS.

  This example is an example of a multi-cavity wiring board for obtaining a wiring board 1b having a cutout portion 4a for mounting an electronic component or the like on the outer side as in the example shown in FIG. . In such a multi-piece wiring board, as shown in FIG. 3A, a recess 4 is formed so as to straddle the two wiring board areas 1a and 1a, and the two wiring board areas 1a and 1a are formed. A dividing groove 2x is formed at the boundary so as to cross the recess 4. By bending the mother board 1 along the dividing grooves 2x, the recesses 4 are divided into two parts, which respectively become the notches 4a of the wiring board 1b. In this case, if the depth of the dividing groove 2x is uniform, the mother substrate 1 is easily cracked easily if the depth of the dividing groove 2x is deeper than the recess 4, and conversely if the depth of the recess 4 is shallower than the recess 4, There is a problem that the bottom surface does not break along the boundary line. For this reason, as in the example shown in FIG. 3B, the depth d <b> 2 of the portion crossing the recess 4 is preferably deeper than the recess 4, and the depth d <b> 1 of the other portion is preferably the split groove 2 x shallower than the recess 4. If it does in this way, while the bottom face of the recessed part 4 will be divided | segmented favorably, it will become the multi-piece wiring board by which the mother board 1 does not crack carelessly. At this time, as in the example shown in FIGS. 3 and 4, the hole 3 extending from the bottom end of the deeper groove to the other main surface is formed in a portion where the depth of the dividing groove 2 is discontinuously different. If formed, the corners that are the starting points of cracks that cause burrs and chips do not exist. Therefore, when dividing the multi-cavity wiring board along the dividing groove 2, the dividing groove having a larger depth is used. The mother substrate 1 can be divided by favorably progressing cracks from the bottom of the substrate toward the other main surface side, and burrs and chips generated in each wiring substrate 1b can be reduced.

  In addition, as in the example shown in FIGS. 1 to 4, the multi-cavity wiring board according to the present invention has the above-described configuration in which the opening width of the dividing groove 2 on the one main surface of the mother board 1 is uniform in the length direction. In some cases, the outer edge on one main surface of each wiring board region 1a is a straight line, so that the outer edge of each wiring board region 1a can be well recognized by an image recognition device or the like, and electronic components are mounted on each wiring board region 1a. Is preferable because it becomes a multi-piece wiring board capable of achieving good positional accuracy with reference to the outer edge of each wiring board region 1a.

  Further, according to the wiring board 1b of the present invention, since the multi-piece wiring board having the above configuration is divided along the dividing groove 2, there is no large burr or chip at the outer edge of the wiring board 1b. Therefore, the outer edge of the wiring board 1b can be well recognized by an image recognition device or the like, and the mounting of electronic components on the wiring board 1b can be performed with good positional accuracy with reference to the outer edge of the wiring board 1b. It becomes.

  Further, according to the electronic device of the present invention, since the electronic component is mounted on the wiring board 1b having the above-described configuration, the outer edge of the electronic device is free from large burrs and chips, so that the outer edge of the electronic device can be recognized. The electronic device can be recognized well by the device or the like, and the electronic device can be mounted on the external electric circuit board with good positional accuracy with reference to the outer edge of the electronic device.

  The base substrate 1 is an electric insulation made of a ceramic material such as an aluminum oxide sintered body, a mullite sintered body, an aluminum nitride sintered body, a silicon carbide sintered body, a silicon nitride sintered body, or a glass ceramic. A plurality of wiring board regions 1a in which wiring conductors made of metal powder metallization such as tungsten, molybdenum, copper, and silver are formed in a central portion of a conductive insulating substrate are arranged vertically and horizontally.

  If the insulating substrate is made of, for example, an aluminum oxide sintered body, an appropriate organic binder and solvent, plasticizer, dispersant, etc. are added to ceramic raw material powder such as aluminum oxide, silicon oxide, magnesium oxide, and calcium oxide. The ceramic slurry obtained by mixing is formed into a sheet by adopting a conventionally known sheet forming method such as a doctor blade method to obtain a ceramic green sheet. After that, the ceramic green sheet is appropriately punched and necessary. Accordingly, a plurality of these are laminated to produce a formed shape and fired at a temperature of about 1500 to 1800 ° C. to produce one or a plurality of insulating layers.

  The wiring conductor includes a wiring conductor layer disposed between the surface of the insulating base and the insulating layer, and a through conductor that electrically connects the wiring conductor layers that pass through the insulating layer and are positioned above and below. The wiring conductor layer is formed by printing and applying a metallized paste for the wiring conductor layer on a ceramic green sheet for the mother substrate 1 by printing means such as a screen printing method, and baking it together with the generated shape. Prior to the printing and application of the metallized paste for forming the wiring conductor, the through conductor has a through hole for the through conductor formed on the ceramic green sheet for the mother substrate 1 by a punching method using a die or punching or a processing method such as laser processing. It is formed by filling the through hole with a metallized paste for a through conductor by a printing means such as a screen printing method, and firing together with the generated shape. The metallized paste is prepared by adding an organic binder, an organic solvent, and a dispersant as required to the metal powder of the main component and mixing and kneading by a kneading means such as a ball mill, a three roll mill, a planetary mixer or the like. Further, glass or ceramic powder may be added in order to match the sintering behavior of the ceramic green sheet or to increase the bonding strength with the mother substrate after firing. The metallized paste for through conductors is adjusted to have a higher viscosity than the metallized paste for wiring conductor layers, which is suitable for filling, depending on the type and amount of organic binder or organic solvent.

  In addition, the metal which is excellent in corrosion resistance, such as nickel and gold | metal | money, is adhered to the exposed surface of a wiring conductor as needed. As a result, corrosion of the wiring conductor can be effectively suppressed, the wiring conductor and the electronic component are fixed, the wiring conductor and the bonding wire are joined, and the wiring conductor and the wiring conductor of the external electric circuit board are connected. Can be strengthened. 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 are sequentially deposited on the exposed surface of the wiring conductor 3 by an electrolytic plating method or an electroless plating method. Is done.

  The dividing groove 2 has a portion in which the depth from one main surface is discontinuously different. However, the depth of the dividing groove 2 varies discontinuously in a certain region. Indicates to do. As shown in the example shown in FIGS. 1 to 4, in one divided groove 2, a groove having a depth d <b> 1 and a groove having a depth d <b> 2 deeper than the depth d <b> 1 are adjacent in the length direction of the divided groove 2. It is what. In the example shown in FIGS. 1 to 4, the dividing groove 2 has only two depths, but may have a depth larger than that.

  The dividing groove 2 is formed at the boundary of each wiring board region 1 a on one main surface of the mother board 1. As shown in the examples shown in FIGS. 1 to 4, the dividing groove 2 has a V-shaped longitudinal cross-sectional shape. In this way, when the mother substrate 1 is bent and broken along the dividing groove 2, the bottom of the dividing groove 2 has a shape in which stress is likely to concentrate, so that the breaking is easy and accurate.

  The depth of the dividing groove 2 is the (d2) portion having a deep depth irrespective of the ratio of the length of the deep (d2) portion and the length of the shallow (d1) portion in one dividing groove 2. Is about 55 to 75% of the thickness of the mother substrate 1, and the shallow portion (d1) is about 45 to 65% of the thickness of the mother substrate 1, and the average depth in the length direction of the dividing groove 2 is the mother depth. If it is about 50-70% of the thickness of the board | substrate 1, while it will be divided | segmented favorably, it will become a multi-piece wiring board which the mother board | substrate 1 does not crack carelessly.

  Further, as in the example shown in FIGS. 3 and 4, when the dividing groove 2 crosses the recessed portion 4, the depth d <b> 2 of the dividing groove in the portion crossing the recessed portion 4 is the thickness of the bottom portion of the recessed portion 4 (the recessed portion 4. The depth d1 of the dividing groove 2 in the other part is 50 to 70% of the thickness of the mother board 1. The thickness between the bottom surface of the mother board 1 and the other main surface of the mother board 1 is approximately 50 to 70%. Formed to a degree.

  When the opening width of the dividing groove 2 on the one main surface of the mother board 1 is about 0.05 to 1.0 mm, it can be divided satisfactorily, each wiring board region 1a is not reduced, and wiring is formed when the dividing groove 2 is formed. It is preferable because the substrate region 1a is not greatly deformed.

  When the concave portion 4 is formed, the length of the deep portion of the dividing groove 2x depends on the size of the concave portion 4. In order to divide satisfactorily without occurrence of burrs or chips below the bottom surface of the recess 4, the length of the deep portion of the dividing groove 2 x is the recess 4 as in the example shown in FIGS. 3 and 4. It is preferable that the dividing groove 2x is formed on the bottom surface of the concave portion 4 as in the example shown in FIG. FIG. 5A is a plan view showing an example of a main part of an embodiment of the multi-cavity wiring board according to the present invention, and FIG. 5B shows a cross section taken along line AA of FIG. It is sectional drawing.

  Moreover, it is preferable that the mother board 1 has a dummy area | region in the outer peripheral part of the center part in which the some wiring board area | region 1a was arranged vertically and horizontally. The dummy area is an area for facilitating the manufacture and transportation of the multi-piece wiring board. Using the dummy area, the generated shape to be the mother board 1 and the positioning when the multi-piece wiring board is processed or carried. Can be fixed. Further, if both end portions of the dividing groove 2 are formed so as to be positioned in a dummy region between the wiring substrate region 1a arranged on the outermost periphery and the outer peripheral portion of the generated shape to be the mother substrate 1, This is preferable because it is possible to prevent the mother substrate 1 from being carelessly broken by a force applied from the outside during conveyance of the substrate 1. A dummy region may be provided between the plurality of wiring board regions 1a. In this case, the dividing groove 2 is formed between the wiring board region 1a and the dummy region.

  6A to 6C are cross-sectional views showing an example of a process for manufacturing the multi-cavity wiring board of the present invention. In FIG. 6, 1 ′ is a generated shape to be a mother substrate 1, 2 ′ (2 x ′, 2 y ′) is a dividing groove 2 (2 x, 2 y), a cut formed in the generated shape 1 ′, 3 ′ is a hole 3 is a hole formed in the generated shape 1 ′, 4 ′ is a recess 4, and a recess 5 is formed in the generated shape 1 ′, and 5 is a cutter blade. FIG. 6 shows a cut 2 ′ (2x ′, 2x ′, 2x, 2y) that forms the dividing groove 2 (2x, 2y) in the generated shape 1 ′ in the process of manufacturing the multi-piece wiring board of the present invention as in the example shown in FIG. 2y ′) is shown. FIG. 7 is a perspective view showing an example of the cutter blade 5 shown in FIG.

  The dividing groove 2 is formed as follows, for example. First, as in the example shown in FIG. 6A, the cutter blade 5 and the mold are pressed against the generated shape 1 ′ to be the base substrate 1 to form the cuts 2 ′ to be the divided grooves 2. The cutter blade 5 and the metal mold at this time have a V-shaped cutting edge as in the example shown in FIG. In the example shown in FIG. 6A, a cutter blade 5 having two height blades corresponding to the shape of the dividing groove 2x having two depths d1 and d2 is used. Thereby, as shown in FIG. 6 (b), it is possible to simultaneously form incisions having two different depths, that is, the depth d1 ′ that becomes the depth d1 after firing and the depth d2 ′ that becomes the depth d2 after firing. it can. Further, the notches 2 ′ having different depths d1 ′ and d2 ′ may be formed separately. However, when a cutter blade 5 having two height blades as shown in FIG. 6A is used. The accuracy of the lengths of the different depths d1 and d2 of the dividing groove 2 can be easily increased. Next, as in the example shown in FIG. 6C, by forming the notch 2y ′ orthogonal to the previously formed notch 2x ′, the dividing groove 2 was formed at the boundary of the wiring board region 1a after firing. A multi-piece wiring board can be obtained. In FIG. 6, the notch 2x ′ that forms the dividing groove 2x that overlaps the concave portion 4 ′ of the generated shape 1 ′ is formed first, but this may be formed later, or the notches 2x ′ and 2y ′ that are orthogonal to each other. You may use the metal mold | die which can form both simultaneously.

  Further, as in the example shown in FIG. 6, the length of the high portion of the cutter blade 5 for forming the cut 2x ′ that overlaps the concave portion 4 ′ of the generated shape 1 ′ is the concave portion 4 of the generated shape 1 ′. If the length is longer than ', the misalignment between the cutter blade 5 and the recess 4' of the generated feature 1 'when forming the notch 2x' is absorbed, and it is surely divided into the bottom surface of the recess 4 'of the generated feature 1'. Since the groove 2x can be formed, it is more preferable. In order to absorb the misalignment, the length of the higher portion of the cutter blade 5 is preferably about 0.1 mm to 1 mm longer than the length of the recess 4 ′ of the generated shape 1 ′ in the direction along the cut 2 x ′.

  Further, in order to form the dividing groove 2 in which the opening width on the one main surface of the mother substrate 1 is uniform in the length direction, for example, a cutter blade 5 as shown in FIG. 7 may be used. In the cutter blade 5, the cutting edge portion having a triangular cross-sectional shape pushed into the generated shape 1 ′ has different heights d1 ′ and d2 ′ according to different cutting depths d1 ′ and d2 ′. The width of the root part is the same.

  The depth of the hole 3 may be at least from the bottom of the deeper groove to the other main surface, but as shown in the example shown in FIG. It may be one that penetrates through the mother board 1 reaching the surface side. If the hole 3 is not provided, a space is formed at the bottom end (corner) of the deeper groove, which is the origin of cracks that cause burrs and chips. Good.

  The cross-sectional shape of the hole 3 is not particularly limited, such as a circular shape, an elliptical shape, a polygonal shape such as a quadrangular shape or an octagonal shape, but is circular or elliptical so as not to cause a crack starting from the corner of the hole 3. If it is a shape or a polygon, a shape with rounded corners is preferable.

  The size of the hole 3 in plan view may be smaller than the opening width of the dividing groove 2 as in the example shown in FIG. 2, or may be equal to the opening width of the dividing groove 2 as in the example shown in FIG. Alternatively, it may be larger than the opening width of the dividing groove 2 as in the example shown in FIG. In order to make the outer edge of the one main surface of the wiring board region 1a straight, the size of the hole 3 in plan view is preferably equal to or smaller than the opening width of the dividing groove 2 and is located within the opening width of the dividing groove 2 in plan view. .

  In order to form the hole 3, a through hole for the hole 3 is formed on the ceramic green sheet for the mother substrate 1 by a die, punching method by punching or a processing method such as laser processing, and the other main surface is laminated. What is necessary is just to produce the production | generation form 1 'which has the hole 3' opened in this. In the case where the hole 3 penetrates the mother substrate 1, the formed shape 1 ′ is formed without forming the through hole for the hole 3 in the ceramic green sheet, and then the hole 3 ′ is formed by punching using a mold or the like. You can also. In this case, it is preferable to form the hole 3 ′ before forming the cut 2 ′ in the generated shape 1 ′ because the cut 2 ′ is not narrowed due to the pressure at the time of punching the hole 3 ′. In addition, when the hole 3 ′ penetrates the generated shape 1 ′, the notch 2 ′ can be formed on the basis of the opening of the hole 3 ′ formed on the one main surface side of the generated shape 1 ′. 2 and the hole 3 can be accurately aligned.

  The recessed part 4 should just be the magnitude | size according to the magnitude | size and quantity of electronic components etc. which are mounted there. In addition, the example shown in FIG. 3 is a case where the notch portions 4a are provided on a pair of opposing outer sides of one wiring board 1b, but the number, position, and shape of the notch portions 4a required are different. The corresponding concave portion 4 may be used. The inner surface of the recess 4 has a wiring conductor to which a terminal of the electronic component is connected.

  The concave portion 4 is formed by laminating through holes for the concave portion 4 in some of the ceramic green sheets for the mother substrate 1 by a punching method using a die or punching or a processing method such as laser processing, and is laminated on one main surface. What is necessary is just to produce the production | generation form 1 'which has the recessed part 4' opened.

  Each wiring board region 1a of the mother board 1 may be provided with a so-called cavity for storing electronic components at a position not intersecting with the dividing groove 2 other than the recess 4 serving as the notch 4a. . A seal ring for joining the lid may be formed around each cavity on the one main surface of the mother board 1 in the same manner as the wiring conductor.

  A plurality of wiring boards 1b are produced by dividing such a multi-piece wiring board along the dividing grooves 2, and an electronic device is produced by mounting electronic components on the wiring board 1b. The electronic device may be fabricated by dividing along the dividing grooves 2 after mounting electronic components on each wiring board region 1a of the multi-cavity wiring board.

  Electronic components mounted on the wiring board 1b are semiconductor elements such as IC chips and LSI chips, piezoelectric elements such as crystal oscillators and piezoelectric vibrators, and various sensors.

  For example, when the electronic component is a flip chip type semiconductor element, the electronic component is mounted on the electrode of the semiconductor element via a solder bump, a gold bump, or a conductive resin (anisotropic conductive resin, etc.). This is done by electrically connecting the wiring conductor. Alternatively, for example, when the electronic component is a wire bonding type semiconductor element, the electrode of the semiconductor element and the wiring conductor are electrically connected to each other through a bonding wire after being fixed with a bonding material such as glass, resin, or brazing material. This is done by connecting to. Further, for example, when the electronic component is a piezoelectric element such as a crystal resonator, the piezoelectric element is fixed and the electrode of the piezoelectric element and the wiring conductor are electrically connected by a conductive resin. Moreover, you may mount small electronic components, such as a resistive element and a capacitive element, around the electronic component and in the notch part 4a as needed.

  And an electronic component is sealed as needed. Sealing is done by covering the electronic component with a sealing resin such as epoxy resin, or wiring the lid made of resin, metal, or ceramic placed so as to cover the electronic component with an adhesive such as glass, resin, or brazing material. What is necessary is just to join to a board | substrate.

  The present invention can be variously modified without departing from the gist of the present invention. For example, the dividing groove 2 may be formed also on the other main surface side of the mother substrate 1 in order to divide better. Alternatively, a wiring conductor may be formed on the inner side surface of the hole 3 to form a so-called castellation conductor.

(A) is a top view which shows an example of embodiment of the multi-piece wiring board of this invention, (b) is sectional drawing which shows the AA line cross section of (a), (c) is ( It is sectional drawing which shows the BB line cross section of a). (A) is a top view which expands and shows the A section of Fig.1 (a), (b) is sectional drawing which expands and shows the A section of FIG.1 (c). (A) is a top view which shows an example of embodiment of the multi-piece wiring board of this invention, (b) is sectional drawing which shows the AA line cross section of (a), (c) is ( It is a perspective view of the wiring board obtained by dividing | segmenting the multi-piece wiring board of a). (A) is a top view which expands and shows the A section of Fig.1 (a), (b) is sectional drawing which expands and shows the A section of FIG.3 (b). (A) is a top view which shows an example of the principal part of embodiment of the multi-cavity wiring board of this invention, (b) is sectional drawing which shows the AA cross section of (a). (A)-(c) is sectional drawing which shows an example of the process of manufacturing the multi-piece wiring board of this invention, respectively. It is a perspective view which shows an example of the cutter blade used when manufacturing the multi-piece wiring board of this invention. (A) is a top view which shows an example of the form of the conventional multi-cavity wiring board, (b) is sectional drawing which shows the AA cross section of (a), (c) is (b). It is sectional drawing to which the A section was expanded.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Mother board 1a ... Wiring board area | region 1b ... Wiring board 2 ... Dividing groove 3 ... Hole 4 ... Recess 4a ... Notch part 5 ... ..Cutter blade

Claims (4)

In a multi-piece wiring board in which a plurality of wiring board regions are formed on one main surface of a mother board in which a plurality of wiring board regions are arranged vertically and horizontally on the boundary of the wiring board region, the dividing groove has a depth from one main surface. Has a portion that is discontinuously different, and a hole that extends from the bottom end of the portion where the depth is deep in one division groove to the other main surface is formed in a portion where the depth of the division groove differs discontinuously. A multi-cavity wiring board characterized by having   2. The multi-piece wiring board according to claim 1, wherein an opening width of the dividing groove on one main surface of the mother board is uniform in a length direction.   3. The wiring board according to claim 1, wherein the multi-cavity wiring board according to claim 1 is divided along the dividing groove.   An electronic device in which an electronic component is mounted on the wiring board according to claim 3.

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