JP5142738B2 - Multiple wiring board - Google Patents

Description

  In the present invention, a plurality of wiring board regions serving as wiring boards used for mounting electronic components such as semiconductor elements and surface acoustic wave elements are arranged vertically and horizontally on a mother board, and at the boundaries of the wiring board areas. The present invention relates to a multi-piece wiring board cut by dicing.

  Conventionally, for example, a wiring board used for mounting electronic components such as semiconductor elements and surface acoustic wave elements is a quadrangle made of a sintered body of a nonmetallic inorganic material such as an aluminum oxide sintered body or a glass ceramic sintered body. A structure having a mounting portion for mounting an electronic component on the upper surface of a plate-like insulating substrate, and a plurality of wiring conductors made of a metal material such as tungsten formed from the mounting portion or its periphery to the lower surface of the insulating substrate. Have.

  Such a wiring board is generally manufactured in the form of a so-called multi-cavity wiring board in which a plurality of wiring boards are obtained simultaneously from a single large-area mother board.

  The multi-cavity wiring board has, for example, a structure in which a plurality of wiring board regions serving as wiring boards are arranged in rows and columns on a flat mother board.

Such a multi-piece wiring board is divided into individual wiring boards by performing a cutting process such as dicing on the mother board at the boundary of the wiring board region. In the dicing process, a disc-shaped dicing blade is used in which abrasive grains (abrasive material) such as diamond and aluminum oxide are bonded by a non-metallic inorganic material such as resin or glass, or a binding material such as a metal material. By rotating the dicing blade at a high speed and cutting the mother board, the multi-piece wiring board is divided into individual wiring boards.
JP 2002-350817 A

  However, the multi-cavity wiring board of the above prior art cuts a mother board made of a sintered body of a hard nonmetallic inorganic material such as an aluminum oxide sintered body when the mother board is divided using a dicing blade. As a result, the abrasive grains of the dicing blade are quickly worn out, or the cutting waste of the base substrate adheres to the dicing blade (so-called clogging), and the cutting force of the dicing blade tends to decrease.

  For this reason, there is a problem in that the load applied to the dicing blade during the cutting process is increased, the dicing blade is broken, and the dicing blade must be frequently replaced.

  Also, if the cutting force of the dicing blade decreases during the dicing process (when the dicing blade rotates and cuts the mother board), the contact part of the mother board with the dicing blade is good. There is a problem that the load applied to the mother board increases without being cut, and this part causes problems such as chipping (fine chipping) and cracks (cracks) on the mother board, that is, the individual wiring board. It was. In particular, in recent years, since the size of the individual wiring board has been remarkably reduced, even if slight chipping or the like occurs, the mechanical strength as a wiring board, the reliability of hermetic sealing, etc. tend to be insufficient.

  The present invention has been completed in view of such conventional problems, and an object of the present invention is a multi-piece wiring board in which a mother board is formed of a sintered body of a non-metallic inorganic material, It is an object of the present invention to provide a multi-piece wiring board that can be cut with good workability while suppressing occurrence of defects such as chipping by dicing the mother board at the boundary.

The multi-cavity wiring board of the present invention has a plurality of wiring board regions arranged in a vertical and horizontal arrangement on a mother board made of a sintered body of a nonmetallic inorganic material, and is divided by dicing at the boundary of the wiring board area. A resin layer in which hard particles made of at least one of silicon oxide, a ceramic material, and diamond are dispersed only in a portion of the mother board located on the boundary of the wiring board region. Is characterized by being attached.

  The multi-piece wiring board of the present invention is characterized in that, in the above configuration, the mother board is made of a glass ceramic sintered body and the hard particles are made of silicon oxide.

  The multi-piece wiring board of the present invention is characterized in that, in the above configuration, the mother board is made of an aluminum oxide sintered body and the hard particles are made of an aluminum oxide sintered body.

  That is, the hard particles in the resin layer come into contact with abrasive grains such as diamond of the dicing blade with a certain force, and the falling of the worn abrasive grains exposed on the surface of the dicing blade is promoted. The abrasive grains bonded to the inside of the bonding material are newly exposed on the surface of the dicing blade, and the cutting force is recovered.

  In this case, since the hard particles are only held by the resin material of the resin layer, the hard particles do not continue to contact the dicing blade so strongly that the abrasive grains newly exposed on the surface of the dicing blade are worn again. Along with the removal of the abrasive grains from the dicing blade, it falls off the mother substrate (resin layer). Since the mother substrate is cut by the newly exposed abrasive grains on the surface (cutting surface) of the dicing blade, the cutting process can be performed stably without applying a large load to the mother substrate and the dicing blade. it can. Therefore, it is possible to provide a multi-piece wiring board that can be cut with good workability while suppressing generation of chipping and the like by dicing the mother board at the boundary of the wiring board region.

  Further, in the multi-cavity wiring board of the present invention, when the mother substrate is made of a glass ceramic sintered body and the hard particles are made of silicon oxide, a so-called low-temperature firing of about 1000 ° C. is possible, for example. Even if the mother substrate is formed of a glass ceramic sintered body that has low strength and is susceptible to mechanical destruction such as chipping during dicing, the exposure of new abrasive grains is promoted in the dicing blade. Cutting can be performed without imposing a large load on the substrate, and occurrence of defects such as chipping can be effectively suppressed.

  In this case, since the hardness of the hard particles made of silicon oxide is close to the hardness of the glass component containing silicon oxide in the glass ceramic sintered body forming the mother substrate, abrasive grains suitable for cutting the mother substrate are dicing blades. It is thought that it will be exposed to the surface of.

  In other words, abrasive grains that have been worn to the extent that they cannot effectively cut the base substrate are difficult to cut hard particles, and when they come into contact with the hard particles, a large stress is generated in the direction in which they are peeled off from the bonding material, causing the dicing blade bonding material to It is thought to drop out.

  For example, the hardness of the abrasive grains made of silicon oxide is lower than the abrasive grains of a dicing blade made of diamond (Mohs hardness is 10) (for example, Mohs hardness is 7 for quartz), and the hard particles are the resin material of the resin layer. Since it is only hold | maintained, it can suppress that the newly exposed abrasive grain is abraded by contact with a hard particle.

  Therefore, even when the cutting force of the dicing blade is sufficiently secured and the mother substrate is formed of a glass ceramic sintered body with low mechanical strength, it can be cut without applying a large load to the mother substrate, It is possible to divide into individual wiring boards while suppressing the occurrence of defects such as chipping.

  Further, in the multi-cavity wiring board of the present invention, when the mother substrate is made of an aluminum oxide sintered body and the hard particles are made of an aluminum oxide sintered body, although the mechanical strength is high, it is hard cut. Even if the mother substrate is formed of a difficult aluminum oxide sintered body, exposure of new abrasive grains is promoted in the dicing blade, so that cutting can be performed without imposing a large load on the mother substrate, The occurrence of defects such as chipping can be effectively suppressed.

  In this case, since the hardness of the hard particles made of the aluminum oxide sintered body is close to the hardness of the aluminum oxide sintered body forming the mother substrate, abrasive grains suitable for cutting the mother substrate are formed on the surface of the dicing blade. It will be exposed.

  In other words, abrasive grains that have been worn to the extent that they cannot effectively cut the base substrate are difficult to cut hard particles, and when they come into contact with the hard particles, a large stress is generated in the direction in which they are peeled off from the bonding material, causing the dicing blade bonding material to It is thought to drop out.

  And, for example, the hardness of the abrasive grains made of an aluminum oxide sintered body (the aluminum oxide has a Mohs hardness of 9) is lower than the abrasive grains of a dicing blade made of diamond (Mohs hardness is 10), and the hard particles are resin layers. Therefore, the newly exposed abrasive grains can be prevented from being worn by contact with the hard particles.

  Therefore, the cutting force of the dicing blade is sufficiently ensured, and even when the mother substrate is formed of a hard and hard-to-cut aluminum oxide sintered body, it can be cut without applying a large load to the mother substrate. And can be divided into individual wiring boards while suppressing the occurrence of defects such as chipping.

  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 taken along line AA in FIG. . In FIG. 1, 1 is a mother board and 2 is a wiring board area. A plurality of wiring board regions 9 are basically formed by arranging a plurality of wiring board regions 2 vertically and horizontally on the mother board 1.

  The base substrate 1 is a non-metallic inorganic material such as a glass ceramic sintered body, an aluminum oxide sintered body, an aluminum nitride sintered body, a silicon carbide sintered body, a silicon nitride sintered body, a mullite sintered body, or the like. It is formed of a sintered body of material.

  The plurality of wiring board regions 2 arranged on the mother board 1 are areas that each become an individual wiring board (not shown). A plurality of wiring boards are manufactured by cutting the mother board 1 at the boundary 2b of the wiring board region 2.

  When an individual wiring board is used as an electronic component mounting board, an electronic component mounting portion is provided at the center or lower surface of the upper surface of the wiring board region 2. In this example, a concave portion 2a is provided in the central portion of the upper surface of the wiring board region 2, and the bottom surface of the concave portion 2a is an electronic component mounting portion (no symbol).

  Note that the mother board 1 does not need to have such a recess 2a in the wiring board region 2, but is a flat plate (not shown) and has a flat upper surface or lower surface of the wiring board region 2. A part of the mounting part may be used.

  Electronic components (not shown) mounted on the mounting unit include semiconductor integrated circuit elements such as IC and LSI, and optical semiconductor elements such as LED (light emitting diode), PD (photodiode), and CCD (charge coupled device). Various electronic devices such as semiconductor devices including surface acoustic wave devices, piezoelectric devices such as surface acoustic wave devices and crystal resonators, capacitive devices, resistors, and micromachines (so-called MEMS devices) in which a minute electromechanical mechanism is formed on the surface of a semiconductor substrate. Parts.

  The electronic component has a resin adhesive such as an epoxy resin, a polyimide resin, an acrylic resin, a silicone resin, a polyether amide resin, Au-Sn, Sn-Ag-Cu, or Sn-Cu on the mounting portion. , Sn-Pb or the like, glass or the like.

  In this example, the wiring conductor 3 is formed from the outer peripheral portion of the mounting portion to the lower surface of the wiring board region 2. The wiring conductor 3 is electrically connected to an electronic component mounted on the mounting portion, and functions as a conductive path that electrically connects the electronic component to an external electric circuit.

  The wiring conductor 3 is formed of a metallized layer made of a metal material such as copper, silver, palladium, platinum, gold, tungsten, molybdenum, or manganese.

  The electrical connection between the electronic component and the wiring conductor 3 is performed, for example, by connecting an electrode (not shown) of the electronic component to a portion of the wiring conductor 3 exposed in the periphery of the mounting portion and conducting the bonding wire, solder or the like. This can be done by connecting via a conductive connecting material.

  Such a mother board 1 in which a plurality of wiring board regions 2 each having wiring conductors 3 are arranged vertically and horizontally can be manufactured as follows, for example.

  First, a raw material powder mainly composed of glass powder such as borosilicate glass containing silicon dioxide and ceramic powder such as aluminum oxide is kneaded with an organic solvent and a binder, and is formed into a sheet by a molding method such as a doctor blade or a lip coater method. To form a ceramic green sheet. Next, powder of a metal material such as copper or silver is kneaded with an organic solvent and a binder to produce a metal paste. Next, the ceramic green sheet is cut into the outer dimensions of the mother substrate 1 and a metal paste is printed on the pattern of the predetermined wiring conductor 3 by a printing method such as a screen printing method in each region to be the wiring substrate region 2. Then, after laminating a plurality of ceramic green sheets, firing is performed at a firing temperature of about 900 to 1000 ° C., whereby a plurality of wiring board regions 2 each having wiring conductors 3 are arranged vertically and horizontally. Can be produced.

  In this example, a dummy region 4 is provided on the outer periphery of the mother substrate 1 so as to surround the plurality of wiring substrate regions 2 arranged. The dummy area 4 is provided to facilitate handling of the multi-piece wiring board 9.

  The multi-piece wiring board 9 is cut by dicing at the boundary 2b of the wiring board area 2 (in this example, the boundary between the wiring board areas 2 and the boundary between the wiring board area 2 and the dummy area 4). Is divided into individual wiring boards (not shown).

  Dividing the mother substrate 1 by dicing processing is performed at a high speed (about 5000) using a dicing blade in which abrasive grains such as diamond and aluminum oxide are bonded with an inorganic material (so-called vitrified) such as glass, or a binder made of a metal material or a resin material. The substrate 1 is rotated at a boundary 2b of the wiring board region 2 and is rotated at a speed of ˜15000 rpm. The positioning of the dicing blade with respect to the mother board 1 is performed by, for example, forming a positioning mark (not shown) on the mother board 1 in advance and recognizing the position by an image recognition device. This positioning mark can be formed on the mother board 1 by the same method using the same material as the wiring conductor 3, for example.

As shown in FIGS. 1 and 2, the multi-cavity wiring board 9 has at least silicon oxide, ceramic material, and diamond only on a portion of the mother board 1 located on the boundary 2b of the wiring board region 2. A resin layer 5 in which hard particles 6 of one kind are dispersed is applied. FIG. 2 is a cross-sectional view schematically showing an enlarged main part of the multi-cavity wiring board 9 shown in FIG. In FIG. 2, the same parts as those in FIG.

  Thus, since the resin layer 5 in which the hard particles 6 are dispersed is attached to the portion of the mother substrate 1 that is located on the boundary 2b of the wiring board region 2 that is the portion to be diced, the dicing processing is performed. Sometimes, the dicing blade is promoted to remove new abrasive grains as well as to cut the mother substrate 1.

  That is, as shown in FIG. 3, the hard particles 6 in the resin layer 5 come into contact with the abrasive grains D such as diamond of the dicing blade B rotating in the R direction so as to be pressed in the R direction with a constant force. The falling of the worn abrasive grains D exposed on the surface of the dicing blade B is promoted, so that the abrasive grains D bonded to the inside of the binder (not indicated) are newly exposed on the surface of the dicing blade B. The cutting force is restored. 3 is an enlarged cross-sectional view schematically showing an enlarged state of a main part when the dicing process is performed on the multi-piece wiring board 9 shown in FIGS. 1 and 2. FIG. The same reference numerals are assigned to the same parts as in FIG.

  In this case, since the hard particles 6 are only held by the resin material (no symbol) of the resin layer 5, they contact the dicing blade B so strongly that the newly exposed abrasive grains D of the dicing blade B are worn again. Without continuing, the abrasive grains D fall off from the dicing blade B and fall off from the mother substrate 1 (resin layer 5), thereby effectively promoting the exposure of new abrasive grains D. Since the mother substrate 1 is cut by the newly exposed abrasive grains D, the cutting can be continuously performed stably without applying a large load to the mother substrate 1. Accordingly, it is possible to provide a multi-piece wiring board 9 that can be cut with good workability while suppressing generation of chipping and the like by dicing the mother board 1 at the boundary 2b of the wiring board region 2. .

  As the resin material for forming the resin layer 5, a thermosetting or light (ultraviolet) curable resin material such as an epoxy resin, a polyimide resin, a phenol resin, an acrylic resin, or a urethane resin can be used.

  The resin material preferably contains a polar group such as an epoxy group or an imide group in the molecular chain in order to ensure the strength of bonding with the mother substrate 1. In this case, since the polar group can be bonded to the sintered body of the nonmetallic inorganic material forming the mother substrate 1 by hydrogen bonding or the like, it is effective that the resin layer 5 is accidentally peeled off from the mother substrate 1. Can be prevented. Examples of the resin material containing such a polar group include an epoxy resin and a polyimide resin. Further, even when the hard particles 6 are made of silicon oxide, if a resin material having such a polar group is used, the oxygen of the silicon oxide and the polar group of the resin material are easily bonded to each other. Inadvertent dropping of the particles 6 can be suppressed.

  The resin material is preferably an epoxy resin or a polyimide resin in view of chemical resistance (alkaline chemicals) resistance, reducing the difference in thermal expansion from the mother board 1 (suppressing thermal stress), and the like. As such an epoxy resin, for example, a bisphenol A type epoxy resin or a novolac type epoxy resin can be used, and a novolac type epoxy resin is particularly preferable for improving chemical resistance.

  The hard particles 6 are made of a material having a small difference in hardness from the abrasive grains D made of diamond or an aluminum oxide sintered body (for example, a material having a Mohs hardness of 7 or more). As the ceramic material as the hard particles 6, materials such as an aluminum oxide sintered body, a boron nitride sintered body, a silicon nitride sintered body, and a silicon carbide sintered body can be used. As the silicon oxide as the hard particles 6, crystalline silicon dioxide such as quartz and cristobalite can be used.

  In this case, it is preferable that the hard particles 6 have a slightly lower hardness (hardness) than the abrasive grains D in order to prevent the newly exposed abrasive grains D from being worn. For example, if the abrasive grains D are made of diamond, the hard particles 6 are preferably made of a ceramic material such as aluminum oxide or silicon oxide, and the abrasive grains D are made of an aluminum oxide sintered body (so-called corundum abrasive grains). Etc.), the hard particles 6 are preferably made of silicon oxide.

  Further, the hard particles 6 preferably have a larger particle diameter in order to effectively drop off the abrasive grains D worn from the dicing blade B. If the particle diameter of the hard particles 6 is too small, the stress acting on the abrasive grains D from the hard particles 6 becomes insufficient, and the action of dropping the abrasive grains D may be reduced. In this case, in order to promote the falling of the hard particles 6 and prevent the newly exposed abrasive grains D from being worn, the particle diameter of the hard particles 6 is preferably the same as or slightly larger than that of the abrasive grains D. . For example, if the average particle size of the abrasive grains D is about 30 to 60 μm (the dicing blade B is about # 300 to # 500, etc.), the hard particle 6 should have a particle size of about 30 to 100 μm. ing.

  Further, the hard particles 6 are in the form of irregular fragments formed by crushing larger raw materials such as quartz and aluminum oxide by mechanical processing, or spherical particles or spherical particles having irregularities on a part of the surface. be able to. In any shape, it is possible to obtain the effect of exposing new abrasive grains D on the surface of the dicing blade B. The hard particles 6 are preferably spherical or spherical with irregularities on a part of the surface in order to achieve uniform dispersion in the resin layer 5.

  In addition, as described above, when a resin material having a polar group, such as an epoxy resin, is used as the resin material for forming the resin layer 5, the hard particles 6 are bonded (bonded) to the resin material and have high strength and dispersibility. In order to ensure a good quality, it is preferable to use an oxide ceramic material such as an aluminum oxide sintered body or silicon dioxide. Even when the hard particles 6 are made of a non-oxide ceramic material such as an aluminum nitride sintered body, a silicon carbide sintered body, or a silicon nitride sintered body, an oxide film is usually formed on the surface thereof. As a result, the bonding strength between the resin material (epoxy resin or the like) and the hard particles 6 can be secured to such an extent that the hard particles 6 do not fall off carelessly.

  The resin layer 5 in which such hard particles 6 are dispersed is, for example, a mixture obtained by kneading a silicon oxide powder together with an uncured epoxy resin to form a paste, and the boundary of the wiring board region 2 in the mother board 1. It can be formed by applying on 2b by a method such as screen printing or roll coating, and then curing the uncured resin by a curing means such as heating or ultraviolet irradiation. As the silicon oxide powder, for example, a spherical shape having an average particle diameter of about 30 to 100 μm or a spherical shape having irregularities on the surface can be used.

  The addition amount of the hard particles 6 to the resin layer 5 may be, for example, about 20 to 80% by mass in order to uniformly hold and disperse the hard particles 6 with the resin material. In this case, a dispersant such as an organic silane compound (so-called silane coupling agent) such as epoxy silane or vinyl silane may be added to the resin layer 5 so that the hard particles 6 are more uniformly dispersed in the resin layer 5.

  The thickness of the resin layer 5 is preferably 500 μm or less in consideration of the productivity, ease of handling, reliability, etc. of the multi-piece wiring board 9. That is, when the resin layer 5 is thick, the resin layer 5 protrudes too much from the surface of the mother board 1, so that when the multi-piece wiring board 9 is handled, the mother layer is accidentally contacted with an apparatus or an operator. It becomes easy to peel off from the substrate 1. Moreover, about the mixture used as the resin layer 5, since it is thick, application | coating becomes difficult, and it becomes easy to produce malfunctions, such as the deformation | transformation by the self weight before hardening of the mixture after application | coating being easy to generate | occur | produce.

  In addition, since the resin layer 5 needs to hold at least the hard particles 6, it is desirable that the resin layer 5 has a thickness at least as large as the particle size of the hard particles 6. For example, if the hard particles 6 have an average particle size of about 30 to 100 μm as described above, the thickness of the resin layer 5 is desirably 100 μm or more. It is more desirable that the thickness be 150 μm or more in order to perform the operation more reliably.

  Further, the width of the resin layer 5 is preferably set to the same width as that of the dicing blade B (about 50 to 300 μm). If the width of the resin layer 5 is set to be about the same as the width of the dicing blade B, when the mother substrate 1 is cut, the exposure of new abrasive grains D is effectively promoted over the entire width of the dicing blade B. It is possible to suppress the occurrence of defects such as chipping on the mother board 1. Further, it is possible to effectively prevent the unnecessary resin layer 5 from remaining on the cut wiring substrate.

  In this example, the resin layer 5 is also extended and attached to the dummy region 4 provided on the outer peripheral portion of the mother board 1. The extended portion 5a of the resin layer 5 to the dummy region 4 can also be deposited by the same method using the same material as the resin layer 5. When the mother board 1 has the dummy area 4, the extension part 5 a of the resin layer 5 may be attached to the dummy area 4 in order to make the cutting of the mother board 1 by the dicing blade B more surely without any trouble. preferable.

  In the multi-piece wiring board 9 in which the extended portion 5a of the resin layer 5 is attached to the dummy area 4, the above-described positioning mark is an extension line to the dummy area 4 at the boundary 2b of the wiring board area 2 (no symbol). If it is formed on the top, the resin layer 5 may be formed of a transparent resin material such as an acrylic resin, or the resin layer 5 may not be formed only on the mark portion so that the mark can be easily recognized. Good.

  Further, a colorant such as an organic dye is added to the resin layer 5 so that the color tone of the resin layer 5 is different from the color tone of the mother substrate 1 so that visual recognition and image recognition can be easily used. You may make it utilize as a pattern for positioning when performing the dicing process on the mother board | substrate 1. FIG.

  Further, in the multi-piece wiring board 9, when the mother board 1 is made of a glass ceramic sintered body and the hard particles 6 are made of silicon oxide, the mother board 1 is fired at a low temperature of about 1000 ° C., for example. Is possible. Therefore, a metallized layer made of a metal material having a low electric resistance (such as copper, silver or gold) (melting point is about 1000 ° C.) is formed as a wiring conductor 3 by simultaneous firing with the insulating substrate 1 to reduce the electric resistance of the wiring conductor 3. Can be suppressed. In addition, even if the mother substrate 1 is formed of a glass ceramic sintered body that can be fired at such a low temperature but has low strength and is susceptible to mechanical destruction such as chipping during dicing, Since the exposure of new abrasive grains D is promoted in the dicing blade B during processing, cutting can be performed without imposing a large load on the mother substrate 1, and the occurrence of defects such as chipping is effectively suppressed. can do. Therefore, it is possible to make a multi-piece wiring board 9 which can be manufactured by suppressing the occurrence of defects such as chipping from a single wiring board having a low electrical resistance.

  In this case, since the hardness of the hard particles 6 made of silicon oxide is close to the hardness of the glass component containing silicon oxide in the glass ceramic sintered body forming the mother substrate 1, abrasive grains suitable for cutting the mother substrate 1 are used. It is considered that D is exposed on the surface of the dicing blade B.

  That is, the abrasive grains D that have been worn to such an extent that the mother substrate 1 cannot be cut cannot effectively cut the hard particles 6, causing a large stress in the direction of peeling from the binder when contacting the hard particles 6. The dicing blade B comes off from the bonding material.

  For example, the hardness of the hard particles 6 made of silicon oxide is lower than that of the abrasive grains D of the dicing blade B made of diamond (Mohs hardness is 10) (for example, the Mohs hardness is 7 for quartz) and the resin of the resin layer 5 Since it is only held by the material, it is suppressed that the newly exposed abrasive grain D is abraded due to the contact between the abrasive grain D and the hard particle 6.

  Therefore, the cutting force of the dicing blade B is sufficiently secured, and even when the mother substrate 1 is formed of a glass ceramic sintered body having low mechanical strength, the mother substrate 1 can be stably provided without applying a large load. It can be cut and divided into individual wiring boards while suppressing the occurrence of defects such as chipping.

  The glass-ceramic sintered body forming the mother substrate 1 is not limited to the main component of borosilicate glass and aluminum oxide as described above, and lithium-based glass and forsterite are sintered together with aluminum oxide. A sintered body or a sintered body containing additives such as zirconium oxide, magnesium oxide, calcium oxide, and zinc oxide can be used.

  Further, in the multi-piece wiring board 9, when the mother board 1 is made of an aluminum oxide sintered body and the hard particles 6 are made of an aluminum oxide sintered body, although the mechanical strength is high, it is hard to cut. Even if the mother substrate 1 is formed of an aluminum oxide sintered body that is difficult to be processed, the exposure of new abrasive grains D is promoted in the dicing blade, so that cutting is performed without imposing a large load on the mother substrate 1. It is possible to effectively suppress the occurrence of problems such as chipping.

  In this case, since the hardness of the hard particles 6 made of the aluminum oxide sintered body is close to the hardness of the aluminum oxide sintered body forming the mother substrate 1, abrasive grains D suitable for cutting the mother substrate 1 are diced. It is considered that the surface of the blade B is exposed.

  In other words, the abrasive grains D worn to such an extent that the mother substrate 1 cannot be effectively cut becomes difficult to cut the hard particles 6, and a large stress is generated in the direction of peeling from the binder when contacting the hard particles 6, resulting in the dicing blade. It is thought that it will fall off from the binder of B.

  For example, the hardness of the abrasive grain D made of an aluminum oxide sintered body (the Mohs hardness of aluminum oxide is 9) is lower than that of the abrasive grain D of the dicing blade B made of diamond (Mohs hardness is 10), and hard particles Since 6 is only held by the resin material of the resin layer 5, the newly exposed abrasive grains D can be prevented from being worn by contact with the hard particles 6.

  Therefore, the cutting force of the dicing blade B is sufficiently secured, and even when the mother substrate 1 is formed of a hard and hard-to-cut aluminum oxide sintered body, cutting is not performed on the mother substrate 1 without applying a large load. It can be divided into individual wiring boards while suppressing the occurrence of defects such as chipping.

  A mother substrate 1 made of an aluminum oxide sintered body is made of a raw material powder obtained by mixing aluminum oxide powder with silicon oxide powder, calcium oxide powder, etc. into a sheet shape together with an organic solvent and a binder to produce a ceramic green sheet. The ceramic green sheet can be manufactured by firing at a firing temperature of about 1300 to 1600 ° C. after being subjected to predetermined processing such as cutting and lamination.

  In addition, the wiring conductor 3 in this case is printed on a ceramic green sheet serving as the mother substrate 1 by simultaneously baking a metal paste prepared by kneading a powder of a metal material such as tungsten or molybdenum together with an organic solvent and a binder, and firing them simultaneously. Can be formed.

  Note that the aluminum oxide sintered body used as the hard particles 6 may have the same composition as the powder of the aluminum oxide sintered body used when the mother substrate 1 is manufactured.

  For example, as shown in a plan view in FIG. 4, the multi-piece wiring board 9 is provided with the dummy area 4 described above so as to surround the wiring board area 2 on the outer periphery of the mother board 1, and the wiring board. When the resin layer 5 (the extended portion 5a of the resin layer 5) is applied on an extension line obtained by extending the boundary 2b of the region 1 to the dummy region 4 with a width wider than the width at the boundary of the wiring substrate region 1 The resin layer 5 (5a) having a sufficiently wide width compared to the width of the dicing blade B can be applied to the mother substrate 1 more easily and reliably. FIG. 4 is a plan view showing another example of the embodiment of the multi-piece wiring board 9 of the present invention. 4, parts similar to those in FIG. 1 are denoted by the same reference numerals.

  Then, by cutting the dummy area 4 with the dicing blade B along the extended line of the boundary 2b of the wiring board area, the exposure of new abrasive grains D is more effectively promoted to the full width of the dicing blade B. Can do. Therefore, in this case, it is possible to provide the multi-piece wiring board 9 that can more effectively suppress the occurrence of chipping and the like and can improve the cutting workability.

  In the case where the resin layer 5 (5a) is deposited on the extended line obtained by extending the boundary 2b of the wiring board region 1 to the dummy region 4 so as to be wider than the width at the boundary 2b of the wiring board region, the width is as described above. In order to obtain the effect as described above, the wider the better.

  In addition, such a configuration has, for example, the width of the resin layer 5 at the boundary 2b between the wiring board regions 2 in order to more surely prevent the unnecessary resin layer 5 from remaining on the divided wiring boards. This is particularly effective in the case where is slightly narrower than the dicing blade B. That is, in such a case, when cutting only the boundary 2b portion of the wiring board region, new abrasive grains D are obtained by cutting the resin layer 5 at both outer edge portions (not indicated) in the width direction of the dicing blade B. It becomes difficult to promote exposure. On the other hand, if the resin layer 5 (5a) is applied to the dummy region 4 with a wide width, both the outer edge portions in the width direction of the dicing blade B, including so-called edge portions, are hard particles in the dummy region 4. The exposure of the abrasive grain D by 6 can be promoted. Therefore, exposure of new abrasive grains D can be promoted more effectively over the full width of the dicing blade B.

  In this case, the resin layer 5 deposited on the boundary between the wiring board region 2 and the dummy region 4 may be widened toward the dummy region 4 side. With such a configuration, when the boundary between the wiring board region 2 and the dummy region 4 is cut at one side of the quadrangular mother board 1, a new outer edge portion in the width direction of the dicing blade B is newly added. The exposure of new abrasive grains D can be promoted, and the exposure of new abrasive grains D can be promoted at the other outer edge portion of the dicing blade B on the other side facing this. Therefore, exposure of new abrasive grains D can be promoted more effectively at both outer edge portions of the dicing blade B.

  Further, when the resin layer 5 (5a) is applied to the dummy region 4 as described above (with a wider width), as shown in an enlarged sectional view of FIG. 5, for example, the resin layer 5 (5a) You may make it adhere | attach so that the thickness of may become thicker than a center part in the both ends of the width direction. 5 is an enlarged cross-sectional view of a main part showing an example of a cross section taken along line BB of the multi-cavity wiring board 1 shown in FIG. 5, parts similar to those in FIGS. 1 and 4 are denoted by the same reference numerals. In FIG. 5, the thickness of the resin layer 5 (ratio of the thickness of the resin layer 5 to the width) is shown larger than the actual thickness.

  Such a configuration is obtained by dicing the resin layer 5 (5a) attached to the dummy region 4 (an extension of the boundary 2b of the wiring board region 2) which is relatively shorter than the boundary 2b between the wiring board regions 2. This is effective for more effectively promoting the exposure of new abrasive grains D at both outer edge portions of the blade B in the width direction. That is, in this case, in the dummy region 4, both outer edge portions in the width direction of the dicing blade B are in contact with the resin layer, so that the new abrasive grains D are effectively exposed at both outer edge portions. Can be promoted.

  In order to deposit the resin layer 5 (5a) in the dummy region 4 so that the thickness is thicker than that of the central portion at both end portions in the width direction, for example, first, the resin layer 5 (5a) is not yet formed. After the mixture of the cured product and the hard particles 6 is applied to the predetermined width of the resin layer 5 (5a) with a thickness corresponding to the thickness at the center, the mixture is additionally applied to both ends in the width direction. You can do it.

  Note that the resin layer 5 (5a) in the dummy region 4 is not limited to the example shown in FIG. 4, and covers, for example, one that extends to the outer surface of the mother substrate 1 or covers the entire dummy region 4. Something like that. When the resin layer 5 (5a) is deposited so as to cover the entire surface of the dummy region 4, for example, as shown in an enlarged view of the main part in FIG. A portion C where the resin layer 5 (5a) is not attached may be provided on the extension line 2b or between the extension lines and used as a positioning mark for the dicing blade B. The portion C to which the resin layer 5 (5a) is not deposited may be a shape that can be used as a positioning mark, such as a quadrangular shape such as a rectangular shape or a triangular shape. FIG. 6 is an enlarged plan view of a main part showing another example of the embodiment of the multi-piece wiring board 1 of the present invention. In FIG. 6, the same parts as those in FIGS. 1 and 4 are denoted by the same reference numerals.

  In this case, if the color tone of the resin layer 5 is made different from the color tone of the mother substrate 1 by means such as addition of a colorant as described above, recognition by image recognition or the like of the portion C where the resin layer 5 (5a) is not deposited is performed. It can be done more easily.

  The wiring board region 2 may be divided into individual pieces after electronic components are mounted on the wiring board region 2. When dicing is performed after the electronic component is mounted on the wiring board region 2, especially when the electronic component has a mechanical movement mechanism such as a MEMS element or a surface acoustic wave element, cutting associated with dicing is performed. When debris adheres to an electronic component, the mechanical movement is hindered and the possibility of malfunctioning increases. Therefore, in this case, it is preferable to first dice the mother substrate 1 after sealing the electronic component with a sealing means (not shown) such as a lid or a sealing resin.

  Electronic devices in which electronic components are mounted on individual wiring boards are used as components in various electronic devices such as computers, mobile phones, digital cameras, and various sensors such as acceleration and pressure. The electrical connection between the electronic device and the electronic device (circuit board or the like constituting the electronic device) is performed by, for example, soldering or conductive bonding of a portion of the wiring conductor 3 exposed on the lower surface of the wiring substrate (wiring substrate region 2). It can be performed by bonding via a conductive bonding material such as an agent.

  A square flat base substrate having a thickness of 1 mm and an outer dimension of 50 × 50 mm was prepared from a glass ceramic sintered body. A rectangular wiring board area with a side length of 2.5 x 3.5 mm is arranged in the center of the mother board in 16 x 13 vertical and horizontal arrangements, and a dummy area on the outer periphery (outside of the wiring board area array) A multi-cavity wiring board was prepared.

  The mother substrate made of a sintered glass-ceramic is a raw material made mainly of about 50% by mass of borosilicate glass containing silicon dioxide and about 40% by mass of aluminum oxide, and added with auxiliary agents such as magnesium oxide and calcium oxide. The powder was formed into a sheet by a doctor blade method together with an organic solvent and a binder to produce a plurality of ceramic green sheets, which were laminated (five layers) and then fired at about 1000 ° C.

  On the mother board, a mounting part for electronic components was provided at the center of the upper surface of the wiring board region, and a wiring conductor made of a copper metallized layer was formed from the mounting part to the lower surface through the inside of the mother board. The copper metallization layer is a screen printing method in which copper metal paste prepared by kneading copper powder with an organic solvent and a binder is applied to the surface of the ceramic green sheet and the inside of the through holes previously formed in the ceramic green sheet. It was formed by coating and filling. The through hole of the ceramic green sheet was formed by mechanical punching by punching a metal pin through the ceramic green sheet in the thickness direction.

  On this mother board, a resin layer in which hard particles of silicon oxide are dispersed is applied to the part located on the boundary between the wiring board areas (the boundary between the wiring board areas and the boundary between the wiring board area and the dummy area). Thus, the multi-piece wiring board of the example was manufactured.

A thermosetting epoxy resin was used as the resin material for forming the resin layer. Quartz, which is crystalline silicon dioxide (SiO ₂ ), was used as the hard particle silicon oxide, and spherical particles were dispersed in the resin layer at a ratio of 50% by mass. This resin layer was deposited by adding a silicon oxide powder to an uncured and fluid epoxy resin and kneading it, and applying the paste to the boundary of the wiring board region by screen printing. .

  In addition, as a comparative example, a multi-piece wiring board in which a resin layer is not deposited on the mother board manufactured as described above was manufactured.

  The multi-cavity wiring boards of these examples and comparative examples were set on the stage of a dicing machine and subjected to dicing while recognizing the boundary of the wiring board area with an image recognition device. The recognition of the position of the boundary of the wiring board area by the image recognition apparatus is performed by forming a pair of rectangular positioning marks in the dummy area so as to sandwich the extension line of the wiring board area, and This was done by recognizing the gap as the boundary of the wiring board region. The positioning mark is printed on the ceramic green sheet with the same metal paste as that used to form the wiring conductor, simultaneously with the printing of the metal paste for the wiring conductor (with both printed patterns on the same plate surface). Formed by.

  Dicing is performed by cutting a mother board by rotating a dicing blade (width 100 μm) with diamond abrasive grains bonded by glass at a rotational speed of about 5000 revolutions / minute. The wiring board was divided into pieces to produce individual wiring boards. The individual wiring boards were checked for the presence or absence of chipping and cracks by observing the appearance (magnification 20 times).

  As a result, in the example of the multi-cavity wiring board of the present invention, chipping and cracks that would be defectives in the individual wiring board did not occur, whereas in the comparative example, about 10% of the individual pieces were obtained. Chipping occurred in the wiring board. As a result, it was confirmed that the multi-cavity wiring board of the present invention can be cut while suppressing generation of defects such as chipping by dicing the mother board at the boundary of the wiring board region.

(A) is a top view which shows an example of embodiment of the multi-piece wiring board of this invention, (b) is sectional drawing in the AA line. It is an expanded sectional view which expands and shows typically the principal part of the multi-cavity wiring board shown in FIG. It is an expanded sectional view which expands and shows typically the state of the principal part when performing the dicing process with respect to the multi-piece wiring board shown in FIG. 1 and FIG. It is a top view which shows the other example of embodiment of the multi-piece wiring board of this invention. It is a principal part expanded sectional view which expands and shows an example of the principal part in the multi-cavity wiring board shown in FIG. It is a principal part enlarged plan view which shows the other example of embodiment of the multi-piece wiring board of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Mother board 2 ... Wiring board area | region 2a .... Recessed part 2b .... Border 3 of a wiring board area ... Wiring conductor 4 ... Dummy area 5 ... Resin layer 5a ... Extension of resin layer Part 6 ... Hard particles 9 ... Multi-cavity wiring board B ... Dicing blade D ... Abrasive grain C ... Part where the resin layer is not deposited

Claims (3)

  A plurality of wiring board regions are arranged in a matrix in a vertical and horizontal arrangement on a mother substrate made of a sintered body of a non-metallic inorganic material, and a multi-piece wiring board divided by dicing at the boundary of the wiring board region, A resin layer in which hard particles composed of at least one of silicon oxide, ceramic material, and diamond are dispersed is attached only to a portion of the mother board located on the boundary of the wiring board region. Multi-cavity wiring board.   2. The multi-cavity wiring board according to claim 1, wherein the mother board is made of a glass ceramic sintered body, and the hard particles are made of silicon oxide. 2. The multi-cavity wiring board according to claim 1, wherein the mother board is made of an aluminum oxide sintered body, and the hard particles are made of an aluminum oxide sintered body .

Images