JP4458974B2 - Multiple wiring board - Google Patents

Description

  The present invention relates to semiconductor integrated circuit elements such as IC and LSI, LD (semiconductor laser), LED (light emitting diode), PD (photodiode), CCD, line sensor, image semiconductor and other optical semiconductor elements, piezoelectric vibrator, crystal A large number of wiring board regions on which the vibrator, surface acoustic wave element, and other various electronic components are mounted are arranged vertically and horizontally in the center of the main surface of the large ceramic substrate. This relates to a wiring board.

  Conventionally, for example, semiconductor integrated circuit elements such as IC and LSI, LD (semiconductor laser), LED (light emitting diode), PD (photodiode), CCD, line sensor, image sensor and other optical semiconductor elements, piezoelectric vibrator, crystal A wiring board used to mount a vibrator, a vibrator such as a surface acoustic wave device, and other various electronic components is mounted on the upper surface of a square plate-like insulating base made of a ceramic material such as an aluminum oxide sintered body. An electronic component mounting portion for mounting an electronic component, and a structure in which a plurality of wiring conductors made of a metal material such as tungsten are disposed from the electronic component mounting portion or its periphery to the lower surface of the insulating base. Have.

  Then, the electronic component is mounted and fixed on the electronic component mounting portion of the insulating base, and the electrode of the electronic component is electrically connected to the wiring conductor through an electrical connection means such as a bonding wire or solder, and the electronic component is An electronic device as a product is obtained by hermetically sealing the component with resin or a lid.

  By the way, with the recent demand for miniaturization of electronic devices, the size of such wiring boards has become extremely small, about several millimeters square, and in order to facilitate the handling of wiring boards Also, in order to efficiently manufacture the wiring board and the electronic device, in the form of a so-called multi-cavity wiring board in which a large number of wiring boards are obtained simultaneously from a single large-area mother board. It has been produced.

  Such multi-cavity wiring boards generally have a plurality of rectangular wiring board regions arranged vertically and horizontally at the center of the main surface of the flat ceramic mother board, and dummy areas on the outer periphery. It has a structure formed. The dummy area is provided to facilitate handling of the multi-piece wiring board.

  At least one of the upper surface and the lower surface of the ceramic mother substrate on which the wiring substrate region is formed is provided with dividing grooves vertically and horizontally along the boundary between the wiring substrate regions and the boundary between the wiring substrate region and the dummy region.

  Then, individual wiring boards can be obtained by dividing the ceramic mother board along the dividing grooves. The division of the ceramic mother board along the dividing grooves means that a bending stress is applied to the ceramic mother board along the dividing grooves, and the ceramic mother board is broken at a portion along the dividing grooves having a low mechanical strength.

  Each dividing groove is formed so that both ends thereof enter the dummy area. When both ends enter the dummy area in this way, the mechanical strength of the dummy area becomes moderately low at the portion adjacent to the wiring board area, and it becomes easy to crack, and when the mother board is divided along the dividing groove It is possible to effectively prevent a large impact from being applied to the wiring board area adjacent to the dummy area, and mechanical damage such as cracks occurs in the wiring board area (particularly, the one adjacent to the dummy area). This can be effectively prevented.

  Such a multi-piece wiring board is manufactured by a so-called ceramic green sheet lamination method. Specifically, first, a raw material powder such as aluminum oxide is formed into a sheet shape to form a plurality of ceramic green sheets, and then a metal paste such as tungsten is formed on the ceramic green sheets with a predetermined pattern such as a wiring conductor. Next, these ceramic green sheets are laminated to form a laminated body. Next, the central portion of the main surface of the laminated body is divided into a plurality of wiring board regions, and the upper and lower surfaces of the laminated body are divided. At least one side is provided with dividing grooves vertically and horizontally along the boundary between the wiring board regions and the boundary between the dummy region and the wiring board region formed outside the plurality of wiring board regions. It is manufactured by baking.

The dividing groove is formed by cutting a cutter blade at a predetermined depth into the main surface of the ceramic green sheet laminate.
JP 2001-130948 A Model 2590335 gazette

  However, in this conventional multi-cavity wiring board, since both ends of the dividing groove enter the dummy area, when a mechanical shock is mistakenly applied during handling of the multi-cavity wiring board, etc. In addition, there is a problem that cracks progress from the both ends of the dividing groove entering the dummy region toward the outside, and the ceramic mother substrate is accidentally cracked.

  If the ceramic mother substrate is cracked in this way, it becomes difficult to handle, and the reliability of hermetic sealing of electronic components becomes low due to the influence of fine cracks remaining inside.

  To solve such a problem, for example, as shown in Patent Document 1, a dummy groove or a dummy groove is formed only at an end of a dummy portion dividing groove (a dividing groove along the boundary between the wiring board region and the dummy region) or an extension thereof. A configuration in which a dummy hole is formed has been proposed. Thereby, when stress concentrates in the dummy part dividing groove, the stress is dispersed by the dummy groove or the dummy hole, and the generation of cracks is suppressed.

  However, in this case, although stress can be prevented from concentrating in the dummy part dividing grooves and cracks can be effectively prevented, in recent years, in response to the demand for further miniaturization of the wiring board, The length of one side of the wiring board region is as very small as 2 to 3 mm, and accordingly, the interval between the divided grooves formed along the boundary between the wiring board regions of the ceramic mother board is further shortened. Therefore, the following new problems have arisen. That is, in the dummy area where the distance between the divided grooves is short and the both ends of each of the dummy grooves enter, the mechanical strength of the ceramic mother board becomes too low near the end of the divided groove, and the divided grooves between the wiring board areas are Cracks are also generated from the edge of the metal, and mechanical cracks such as cracks progress to the side of the ceramic mother board starting from this crack, causing many problems that the ceramic mother board breaks accidentally. It has become. If the ceramic mother board is broken by mistake, cracks (including fine ones) are also generated in each wiring board region, and the reliability of hermetic sealing is lowered.

  In particular, recently, so-called low-temperature fired substrates such as glass ceramics have come to be frequently used as the material of the ceramic mother substrate, and the mechanical strength of such low-temperature fired substrates is generally low. The occurrence of problems such as cracking of the ceramic mother board is becoming remarkable.

  Further, as the wiring board (ceramic mother board) is made thinner (the thickness of the mother board is 0.5 mm or less, etc.), the problem of cracks has become more prominent.

  The present invention has been devised in view of such conventional problems, and the purpose thereof is, for example, even if the ceramic mother substrate is composed of a low-temperature fired substrate and the thickness of the wiring substrate is 0.5 mm or less. In addition, even if a crack occurs from the end of the dividing groove, the ceramic mother board is not accidentally cracked, and it is easy to handle and has a highly reliable multi-piece wiring board such as hermetic sealing. It is to provide.

The multi-cavity wiring board of the present invention includes a ceramic mother board in which square-shaped wiring board regions are arranged vertically and horizontally at the center and a square frame-like dummy region is formed on the outer periphery, and the ceramic mother board Divided grooves formed on at least one of the upper surface and the lower surface along the boundary between the wiring board regions and the boundary between the wiring board region and the dummy region and both ends enter the dummy region, and the dummy region A plurality of groove portions intermittently formed over the entire circumference so as to be parallel to the outermost division groove and intersecting the extension line of the division groove, and the plurality of groove portions are respectively rather long than the spacing between the dividing grooves to each other in length adjacent to the mutually adjacent to each other in each side of the dummy region is not located on one straight line, and prior to Each of the sides of the dummy region is formed so as to be alternately located on the inner peripheral side and the outer peripheral side, and the plurality of groove portions positioned on the inner peripheral side and the plurality of groove portions positioned on the outer peripheral side are: The lengths of the dummy regions are the same and are located on the inner side and the outer side with respect to the center line in the width direction of the dummy region, and the distance from the center line is the same on the inner peripheral side and the outer peripheral side. it is characterized in that.

  According to the multi-cavity wiring board of the present invention, a ceramic mother board in which square wiring board regions are arranged vertically and horizontally in the center and dummy areas are formed in the outer periphery, and the upper and lower surfaces of the ceramic mother board And at least one of them is formed along the boundary between the wiring board areas and the boundary between the wiring board area and the dummy area, and both ends of the dividing groove enter the dummy area and intersect with the extension line of the dividing groove of the dummy area. A plurality of groove portions intermittently formed over the entire circumference so as to be parallel to the outermost divided groove, and the plurality of groove portions are each between adjacent divided grooves. Since it is longer than the interval, even if a crack starts to progress along the extension line of the dividing groove from both ends of the dividing groove toward the side surface of the ceramic mother substrate, the progress of the crack It is effectively blocked by a plurality of grooves formed intermittently over the entire circumference of the dummy region so as to intersect with the extension line of the dividing groove, and is effectively prevented from reaching the side surface of the ceramic mother substrate. It is possible to suppress the occurrence of problems such as mechanical destruction such as cracking of the substrate and a decrease in the reliability of hermetic sealing of each wiring substrate region (wiring substrate) resulting therefrom.

Also, multiple patterning wiring board of the present invention, the groove of the multiple, since the adjacent groups from one another at each side of the rectangular frame-shaped dummy region is formed so as not located on one straight line, It is effectively prevented that stress concentrates and acts so as to connect the end portions of adjacent groove portions in a straight line. Therefore, it is possible to prevent cracks from advanced generated in the ceramic base substrate effectively, provide a multi-piece wiring substrate capable of forming a wiring board having excellent reliability of the hermetic seal can do.

Also, multiple patterning wiring board of the present invention, the groove of the multiple is formed so as to be positioned alternately on the inner and outer circumferential sides in each side of the rectangular frame-shaped dummy region, the inner peripheral side The plurality of groove portions located on the outer periphery side and the plurality of groove portions located on the outer peripheral side have the same length and are located on the inner side and the outer side, respectively, with respect to the center line in the width direction of the dummy region. from the same der Rukoto in that the inner and outer circumferential sides distance from, the stress acting on the plurality of grooves, can be effectively dispersed alternately the inner and outer circumferential sides of the dummy region, these cracks, such as to connect a plurality of grooves in a straight line is generated is prevented effectively, easy the handling is provided a very high multiple patterning wiring board of reliability of the hermetic sealing of electronic components can do.

  Next, the multi-piece wiring board of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a plan view showing an example of an embodiment of a multi-piece wiring board according to the present invention, wherein 1 is a ceramic mother board, 2 is a dividing groove, and 3 is a wiring conductor. By dividing the ceramic mother board 1 vertically and horizontally with the dividing grooves 2, a plurality of wiring board regions 4 are arranged vertically and horizontally at the center of the main surface of the ceramic mother substrate 1, and a large number of dummy areas 5 are formed on the outer periphery. A wiring board is formed.

  The ceramic mother substrate 1 is made of an electrically insulating material such as a flat glass ceramic, an aluminum oxide sintered body, an aluminum nitride sintered body, a mullite sintered body, a silicon nitride sintered body, and a silicon carbide sintered body. Consists of.

  When the ceramic mother substrate 1 is made of, for example, glass ceramics, an appropriate organic binder and solvent are added to and mixed with a raw material powder such as glass such as borosilicate glass or aluminum oxide or silicon oxide, and a slurry slurry. At the same time, a ceramic green sheet (ceramic green sheet) is obtained by forming this ceramic slurry into a sheet by employing a sheet forming technique such as a doctor blade method or a calender roll method, and then the ceramic green sheet is cut. A suitable shape is obtained by processing or punching, and a plurality of these are laminated as necessary. Finally, the ceramic green sheet is fired at a temperature of about 1000 ° C. in a reducing atmosphere.

  In the central portion of the main surface of the ceramic mother board 1, a plurality of rectangular wiring board regions 4 are arranged in rows and columns.

  Each wiring board region 4 is a region that becomes an individual wiring board, and has a mounting portion for mounting an electronic component (not shown) at the center of the upper surface thereof. In the example of FIG. 1, the mounting portion is the central portion of the upper surface of each wiring board region 4, and does not have a particularly clear boundary. The mounting portion is not limited to the central portion of the upper surface of the flat wiring board region 4, and a recess (not shown) may be provided in the central portion of the upper surface of the wiring substrate region 4, and the bottom thereof may be used as the mounting portion. .

  Electronic components include ICs, LSIs and other semiconductor integrated circuit elements, LDs (semiconductor lasers), LEDs (light emitting diodes), PDs (photodiodes), CCDs, line sensors, image sensors and other optical semiconductor elements, piezoelectric vibrators, crystals These are vibrators, vibrators such as surface acoustic wave elements, and other various electronic components.

  In each wiring board region 4, a wiring conductor 3 made of a metal material such as copper, silver, molybdenum, tungsten, or the like is formed from the periphery to the lower surface of each mounting portion.

  The wiring conductor 3 is connected to an electrode of an electronic component mounted on the mounting portion, and has a function of leading it to the outside such as the lower surface of each wiring board (each wiring board region 4). For example, an electronic component such as a semiconductor element or a surface acoustic wave element is mounted on the mounting portion, and each electrode of the electronic component is bonded to a portion of the wiring conductor 3 exposed to the mounting portion or its periphery, such as a bonding wire or a solder bump. Are electrically connected via the electrical connection means (not shown), so that each electrode of the electronic component is connected to the wiring board region 4 (actually, the individual wiring boards after being divided) via the wiring conductors 3. ). By connecting the lead-out portion of the wiring conductor 3 to an external electric circuit, the electrode of the electronic component is electrically connected to the external electric circuit.

  If the wiring conductor 3 is made of, for example, copper, a metal paste obtained by adding and mixing an appropriate organic binder and solvent to the copper powder is preliminarily screen-printed on the surface of the ceramic green sheet serving as the ceramic mother substrate 1. For example, it is formed by printing and applying a predetermined pattern.

  The exposed portion of the wiring conductor 3 is preferably coated with a plating layer made of nickel, copper, gold or the like. Thereby, the oxidative corrosion of the wiring conductor 3 can be prevented, and the bonding property of the bonding wire to the wiring conductor 3 and the wettability of the solder bump can be improved. Such a plating layer is formed by a known plating method such as an electrolytic plating method or an electroless plating method.

  In addition, a dummy region 5 is formed outside the region where the plurality of wiring substrate regions 4 are arranged in the ceramic mother substrate 1.

  The dummy area 5 is for facilitating handling of the multi-piece wiring board. Further, it is for facilitating the routing of the wiring conductor 3 (such as routing for supplying a plating current necessary for depositing the plating layer on the wiring conductor 3 by electrolytic plating).

  Further, the ceramic mother substrate 1 is provided with dividing grooves 2 along at least one of an upper surface and a lower surface along a boundary between the wiring substrate regions 4 and a boundary between the wiring substrate region 4 and the dummy region 5.

  The dividing groove 2 is used to divide the ceramic mother substrate 1 and separate the dummy regions 5 and to divide the substrate into individual rectangular wiring substrate regions 4.

  By applying a bending stress to the ceramic mother substrate 1 along the divided grooves 2, the ceramic mother substrate 1 is broken along the portion where the divided grooves 2 having low mechanical strength are formed, and the division is performed.

  For example, such a dividing groove 2 presses a blade (metal blade) having a predetermined cross-sectional shape on the main surface of a ceramic green sheet (laminated body) to be the ceramic mother substrate 1 and enters a predetermined depth. Formed by.

  After obtaining the individual wiring boards by dividing the multi-piece wiring board along the dividing groove 2, the electronic parts are mounted on the mounting portions of the wirings, and the electrodes of the electronic parts are electrically connected. Thus, a large number of electronic devices are formed by electrically connecting to the wiring conductors 3 and sealing the electronic components with a lid or a sealing resin as required.

  The electronic component may be mounted before dividing the multi-piece wiring board into the individual wiring board regions 4. In this case, a multi-piece electronic device is formed in which electronic parts are mounted on the mounting portion of each wiring board region 4, and the multi-piece electronic device is divided along the dividing groove 2 to obtain a large number of pieces. An electronic device is formed.

  In the multi-piece wiring board of the present invention, the plurality of groove portions 6 are intermittently formed over the entire circumference so as to intersect with the extension line of the dividing groove 2 of the dummy region 5 and to be parallel to the outermost dividing groove 2. It is important that the plurality of groove portions 6 be longer than the interval between the adjacent divided grooves 2.

  As described above, the plurality of groove portions 6 are intermittently provided over the entire circumference so as to be parallel to the outermost division groove 2 and intersect with the extension line of the division groove 2 in the dummy region 5. If each length is longer than the interval between the adjacent divided grooves 2, cracks progress along the extended lines of the divided grooves 2 from both ends of the divided grooves toward the side surfaces of the ceramic mother substrate. Even if it starts, the progress of the crack is effectively prevented by the plurality of grooves 6 formed intermittently over the entire circumference of the dummy region so as to intersect the extension line of the dividing groove, and the crack is formed at the end of the ceramic mother substrate. Reaching up to is effectively prevented.

  Accordingly, even if the ceramic mother board 1 is made of glass ceramics or the like, for example, even if the thickness of the product having a wiring board thickness of 0.5 mm or less is reduced, the ceramic mother board as described above is used. Problems such as cracking of the substrate 1 can be effectively prevented, easy to handle, and a highly reliable multi-piece wiring substrate such as an airtight seal of electronic components can be provided.

  In this case, the groove 6 is formed in parallel with the outermost divided groove 2 so that the distance between the groove 6 and the outermost divided groove 2 is the same distance in each groove 6. It is possible to prevent the ceramic mother substrate 1 (dummy region 5) inside the groove portions from becoming uneven in mechanical strength and easily generating cracks in a portion having low mechanical strength. be able to.

  Therefore, the groove 6 needs to be formed in parallel with the outermost divided groove 2.

  In addition, when the length of each of the groove portions 6 is shorter than or equal to the interval between the adjacent divided grooves 2, cracks that progress from the end portions of the divided grooves 2 toward the side surface of the ceramic mother substrate 1. When the traveling direction deviates from the extended line of the dividing groove 2, it becomes impossible to prevent the progress of the crack.

  Therefore, it is necessary to make each length of the groove 6 longer than the interval between the adjacent divided grooves 2.

  When the length of the groove 6 is made longer than the interval between the adjacent divided grooves 2, the end is positioned outside the line inclined outward by at least 15 degrees with respect to the extension line of the divided groove 2. The length is preferably long, and the range of 15 to 45 degrees is even more preferable in consideration of ensuring the mechanical strength of the ceramic mother substrate 1 in the dummy region 5 more reliably.

  In addition, the groove part 6 presses the braid | blade (metal blade) which has a predetermined cross-sectional shape to the main surface of the ceramic green sheet (laminated body) used as the ceramic mother board 1, for example, when forming the division | segmentation groove | channel 2. It is formed at the same time as the dividing groove 2 by making it penetrate to a predetermined depth.

Also, multiple patterning wiring board of the present invention, a plurality of grooves 6, that have adjacent groups from one another at each side of the rectangular frame-shaped dummy region 5 is formed so as not located on one straight line.

Thereby, it is effectively prevented that stress concentrates and acts so as to connect the end portions of the adjacent groove portions 6 in a straight line. Therefore, it is possible to prevent the effective of cracks in the ceramic base substrate 1 proceeds to generate a multi-piece wiring substrate capable of forming a wiring board having excellent reliability of the hermetic seal Can be provided.

Also, multiple patterning wiring board of the present invention, a plurality of grooves 6, that are formed so as to be positioned alternately on the inner and outer circumferential sides in each side of the rectangular frame-shaped dummy region 5.

As a result, the stress acting on the plurality of groove portions 6 can be effectively dispersed alternately on the inner peripheral side and the outer peripheral side of the dummy region 5, and a crack that connects the plurality of groove portions 6 in a straight line is generated. it is prevented effectively that, easy the handling is, it is possible to provide a very high multiple patterning wiring board of reliability of the hermetic sealing of electronic components.

As described above, the plurality of groove portions 6 are alternately formed on the inner peripheral side and the outer peripheral side of the dummy region 5, and what is positioned on the inner peripheral side and what is positioned on the outer peripheral side are: you like the length of each other are the same.

Further, the groove 6, which is located in one and the outer located on the inner peripheral side, with respect to the width direction of the center line of the dummy region 5, situated inside, on the outside, respectively, the inner distance from the center line to be the same in the peripheral side and the outer peripheral side.

  Moreover, about the groove part 6, as for the distance of the straight line which connected what is located in an inner peripheral side, and the straight line which connected what is located in an outer peripheral side, 1 mm or more is preferable.

  Note that the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention. For example, the groove 6 may intersect with the extension line of three or more divided grooves.

It is a top view which shows an example of embodiment of the multi-piece wiring board of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Ceramic mother board 2 ... Divided groove 3 ... Wiring conductor 4 ... Wiring board area 5 ... Dummy area 6 ... Multiple grooves

Claims (1)

A ceramic mother board in which square-shaped wiring board regions are vertically and horizontally arranged in the center and a square frame-like dummy area is formed in the outer periphery, and the wiring board is provided on at least one of the upper and lower surfaces of the ceramic mother board A dividing groove formed along a boundary between regions and a boundary between the wiring board region and the dummy region and having both ends intersecting with the dummy region, and an extension line of the dividing groove in the dummy region and the most. A plurality of groove portions intermittently formed over the entire circumference so as to be parallel to the division grooves located on the outer side, and the plurality of groove portions are formed between the division grooves whose lengths are adjacent to each other. rather long than the distance between, as the mutually adjacent to each other in each side of the dummy region is not located on one straight line, and the inner periphery at the sides of the dummy region And the plurality of groove portions positioned on the inner peripheral side and the plurality of groove portions positioned on the outer peripheral side have the same length. The multi- cavity characterized in that it is located inside and outside the center line in the width direction of the dummy region, and the distance from the center line is the same on the inner peripheral side and the outer peripheral side Wiring board.

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