JP4423181B2 - Multiple wiring board - Google Patents

Description

  The present invention relates to a plurality of wiring boards in which a plurality of wiring board regions on which electronic components such as semiconductor elements and surface acoustic wave elements are mounted are arranged vertically and horizontally on a large-area ceramic mother board.

  Conventionally, for example, wiring boards used for mounting electronic components such as semiconductor elements and surface acoustic wave elements have electronic components mounted on the upper surface of a rectangular flat plate-shaped insulating substrate made of a ceramic material such as an aluminum oxide sintered body. And has 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.

  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 used as necessary. Is hermetically sealed with a resin or a lid to provide an electronic device as a product.

  In this electronic device, a part of the wiring conductor is exposed on the outer peripheral portion of the lower surface, and the exposed part is connected to an external electric circuit (external connection), so that the electronic component can be connected to the outside via the wiring conductor. It is electrically connected to the electric circuit.

  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. In order to efficiently manufacture an electronic device, a “multiple picking” technique is used in which a single mother board is divided to obtain a large number of wiring boards simultaneously.

  In general, a multi-piece wiring board used for such “multi-piece” is generally formed by arranging a plurality of wiring board regions vertically and horizontally in the central part of a flat ceramic mother board, and arranging the wiring on the outer peripheral part. It has a structure in which a marginal area is arranged so as to surround the substrate area. The disposal area is provided in order to simplify the handling of a plurality of wiring boards. Also, in the surrogate area, there are a plurality of wiring boards, and recognition marks such as letters, numbers, symbols, figures, etc. indicating the product name, address, etc. of each wiring board when each wiring board area is divided into pieces. However, it is formed of a conductor or the like similar to the wiring conductor so that a plurality of wiring boards and wiring boards can be reliably identified.

Such a multiple wiring substrate 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 applied to the ceramic green sheets with a predetermined wiring conductor or recognition mark. These ceramic green sheets are laminated to form a laminate, and then fired.
JP 2004-95762 A JP 2004-193292 A JP 1998-215041 A

  However, in the conventional multi-wiring circuit board described above, due to the difference in shrinkage rate during firing between the metal paste serving as the recognition mark and the ceramic green sheet serving as the mother board, the abandoned region, that is, the ceramic green There is a problem that stress acts along the outermost periphery of the laminated body of sheets, and deformation such as warpage occurs in the mother substrate after firing due to the stress acting on the outermost peripheral portion.

  When deformation such as warpage occurs in the mother board, deformation also occurs in each wiring board, resulting in problems such as a decrease in tilt connection reliability of the electronic components to be mounted.

  In particular, due to the recent demand for miniaturization of the wiring board, even a slight deformation has increased the influence, so it is necessary to suppress the occurrence of the deformation. For example, in the case of multiple wiring boards, even if each wiring board is warped little by little, the entire mother board is warped greatly, and it becomes impossible to mount electronic components in the state of the mother board. Greatly affected.

  In addition, as a material of the mother board, the dielectric constant is low and the transmission loss of the wiring conductor is small, low temperature firing is possible, and a low resistance material such as copper or silver can be integrally fired with the mother board to form the wiring conductor. Since the glass ceramic sintered body is often used, the above problem tends to occur frequently. In other words, when a metallized wiring conductor of copper or an alloy containing copper as a main component is formed on the surface of a mother substrate made of a glass ceramic sintered body, since the melting point of the alloy used for the wiring conductor is relatively low, the particle size is When it is excessively small, sintering is likely to proceed quickly, and a shrinkage difference is generated between the mother substrate and the mother substrate is warped.

  The present invention has been devised in view of the above-described problems, and its object is to effectively prevent deformation such as warpage in the mother board while a recognition mark is formed in the surrogate area. Another object of the present invention is to provide a wiring board having a plurality of components that is excellent in practicality and mountability of electronic components.

  A multiple wiring substrate according to the present invention includes a ceramic mother board in which a plurality of wiring board regions are arranged vertically and horizontally in a central portion and an abandoned region is formed in an outer peripheral portion, and one of the main substrates. A plurality of wiring boards having an insulating layer formed on the surface so as to cover the abandoned region, wherein the insulating layer has the same composition as a ceramic component forming the mother board. It includes a ceramic component as a main component, and has an opening pattern that exhibits a color tone different from that of the ceramic forming the mother substrate and exposes the surface of the mother substrate.

  Also, the multiple wiring substrate of the present invention is characterized in that the insulating layer is formed over the entire ablation region on the one main surface and excluding the portion where the opening pattern is formed. .

  According to the multiple wiring substrate of the present invention, the insulating layer formed so as to cover the surplus region includes as a main component a ceramic component having the same composition as the ceramic component forming the mother substrate, and the mother substrate. Because it has an opening pattern that exposes the surface of the mother board and exhibits a different color tone from the ceramic forming the surface, the surface of the mother board that is exposed from the opening pattern, which has a different color tone from the insulating layer, functions as a recognition mark Thus, it is possible to reliably and easily recognize a product name, an address, etc. of a plurality of wiring boards and individual wiring boards when each wiring board region is divided into individual pieces.

  In addition, since the insulating layer covering the abandoned region contains as a main component a ceramic component having the same composition as the ceramic component forming the mother substrate, the mother substrate and the insulating layer have the same degree of shrinkage during firing, A large stress does not occur between the two during firing, and it is possible to effectively prevent problems such as warpage of the mother substrate.

  Furthermore, the multi-layer wiring board of the present invention is the presence or absence of the insulating layer in the surrogate region by forming the insulating layer over the entire surrogate region excluding the opening pattern forming portion on one main surface. Due to the above, variation in stress acting on the mother substrate during firing is suppressed, and deformation of the mother substrate can be extremely effectively prevented.

  Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a plan view showing an example of an embodiment of a multi-chip wiring board according to the present invention. A plurality of wiring board regions are formed by arranging a plurality of wiring board regions 2 vertically and horizontally in the center of the main surface of the mother board 1.

  The base substrate 1 is a ceramic such as a flat glass ceramic sintered body, an aluminum oxide sintered body, an aluminum nitride sintered body, a mullite sintered body, a silicon nitride sintered body, or a silicon carbide sintered body. Made of material.

  When the mother substrate 1 is made of, for example, a glass ceramic sintered body, a suitable organic binder and solvent are added to and mixed with a raw material powder such as borosilicate glass or aluminum oxide, silicon oxide, etc. to form a mud-like shape. A ceramic green sheet (ceramic green sheet) is obtained by forming a ceramic slurry, and forming the ceramic slurry into a sheet shape by adopting a sheet forming technique such as a doctor blade method or a calender roll method, and then the ceramic green sheet. Is formed into an appropriate shape by cutting or punching, and a plurality of them are laminated as necessary, and finally the ceramic green sheet is fired at a temperature of about 1000 ° C. in a reducing atmosphere.

  A plurality of wiring board regions 2 are arranged vertically and horizontally at the center of the mother board 1.

  Each wiring board area 2 is an area that becomes an individual wiring board, and has a mounting portion 5 for mounting an electronic component (not shown) at the center of the upper surface thereof. The mounting portion 5 may be provided on the bottom surface of the recess by forming a recess (not shown) for housing the electronic component on the upper surface of the wiring board region. The mounting portion 5 is not limited to the central portion on the upper surface, and may be provided on the outer peripheral region or on the lower surface.

  The electronic component is a semiconductor element, an optical semiconductor element, a capacitor element, a surface acoustic wave element, a crystal resonator, a ceramic piezoelectric element, or the like, and is joined to the mounting portion via a brazing material, glass, an adhesive, or the like.

  In each wiring board region 2, wiring conductors 6 made of a metal material such as copper, silver, palladium, gold, platinum, molybdenum, and tungsten are formed from the periphery to the lower surface of each mounting portion.

  The wiring conductor 6 is connected to an electrode of an electronic component mounted on the mounting portion 5 and is led out to the lower surface side or the like of each wiring board region 2. For example, an electronic component such as a semiconductor element or a surface acoustic wave element is mounted on the mounting portion 5, and each wire of the electronic component is bonded to a portion of the wiring conductor 6 that is exposed to the mounting portion 5 or its periphery. Are electrically connected via an electrical connection means (not shown) or the like, whereby each electrode of the electronic component is connected to the wiring board region 2 (actually, the individual wiring boards after the division through the wiring conductors 6). ). By connecting the lead-out portion of the wiring conductor 6 to an external electric circuit, the electrode of the electronic component is electrically connected to the external electric circuit.

  If the wiring conductor 6 is made of, for example, copper, a metal paste obtained by adding and mixing an appropriate organic binder / solvent to the copper powder is preliminarily screen-printed on the surface of the ceramic green sheet to be the mother substrate 1. Is formed by printing in a predetermined pattern.

  In addition, it is preferable to deposit a plating layer made of nickel, copper, gold or the like on the exposed portion of the wiring conductor 6. Thereby, the oxidative corrosion of the wiring conductor 6 can be prevented, and the bonding property of the bonding wire to the wiring conductor 6 and the wettability of the solder bump can be improved.

  In addition, a marginal area 3 is provided on the outer periphery of the mother board 1, that is, outside the area of the mother board 1 where the plurality of wiring board areas 2 are arrayed so as to surround the wiring board areas 2. Is formed.

  The disposal area 3 is for making it easy to handle a plurality of wiring boards. In addition, as will be described later, each of the multi-cavity wiring board or a wiring board obtained by dividing the multi-cavity wiring board into individual wiring board areas when each wiring board area 2 is divided into individual pieces. It has a function as a space for forming a recognition mark for recognizing characters, numbers and symbols representing the product name, address, etc.

  In such a multiple wiring board, an electronic component (not shown) is mounted on the mounting portion 5 of each wiring board region 2, and each electrode of the electronic component is connected to the wiring conductor 6 via an electrical connection means. A plurality of electronic devices can be obtained simultaneously by electrically connecting and sealing electronic components with a lid or a sealing resin as necessary, and then dividing the plurality of wiring boards into individual pieces.

  In the multiple wiring substrate 9 of the present invention, the insulating layer 4 is formed so as to cover the marginal region 3, and the insulating layer 4 has a ceramic component having the same composition as the ceramic component forming the mother substrate 1. It is important to have an opening pattern 4 a that is included as a main component and that has a color tone different from that of the ceramic forming the mother substrate 1 and that exposes the surface of the mother substrate 1.

  As described above, the insulating layer 4 is formed so as to cover the separation region 3, and the insulating layer 4 includes a ceramic component having the same composition as the ceramic component forming the mother substrate 1 as a main component, and the mother layer By having an opening pattern 4a that exhibits a color tone different from that of the ceramic forming the substrate 1 and exposes the surface of the mother substrate 1, it is exposed from the opening pattern 4a that has a color tone different from that of the insulating layer 4. The surface of the mother board 1 can function as a recognition mark, and when each wiring board area 2 is divided into individual pieces, the recognition of letters, numbers, symbols, etc. representing the name, address, etc. of each wiring board is ensured. Moreover, it can be made easy.

  Moreover, since the insulating layer 4 covering the surplus region 3 contains a ceramic component having the same composition as the ceramic component forming the mother substrate 1 as a main component, the mother substrate 1 and the insulating layer 4 are contracted at the time of firing. Therefore, it is possible to effectively prevent problems such as warpage in the mother substrate 1 without causing a large stress between the two during firing.

  In addition, the formation method of the insulating layer 4 makes the color tone different from the mother substrate 1 by adding a trace amount of additives such as chromium oxide to a ceramic component having the same composition as the mother substrate 1.

  The insulating layer 4 has a thickness of 5 to 20 μm and is preferably formed to have a width that substantially covers the marginal area 3 in order to minimize the shrinkage difference in the marginal area 3. The opening pattern 4a may be covered by about 3 mm on one side.

  The opening pattern 4a is formed with a pattern of letters, numbers, symbols, figures, etc. in order to function as a recognition mark as described above.

  The opening pattern is formed by forming recognition marks such as letters, numbers, symbols, and figures on the plate making when the ceramic paste to be the insulating layer 4a is printed, and when the insulating layer 4a is printed. This portion is formed so as not to be printed.

  In addition, the insulating layer 4 is preferably formed over the entire abandoned region 3 excluding the formation site of the opening pattern 4a on one main surface.

  In this case, due to the presence or absence of the insulating layer 4 in the abandoned region 3, variations in stress acting on the mother substrate 1 during firing are suppressed, and deformation of the mother substrate 1 can be extremely effectively prevented.

  In this embodiment, it is preferable that one of the insulating layer 4 and the mother substrate 1 is black (dark brown or dark gray), and the other is white (light gray or light). In this case, the contrast between the insulating layer 4 and the surface of the mother substrate 1 can be made very large, the opening pattern 4a can be recognized more easily and reliably, and the recognition can be performed more easily and reliably. The individual wiring board 9 can be obtained.

  In this case, it is preferable that the mother substrate is white (light color) and the insulating layer is black (dark color). In this case, since the insulating layer 4 having a large area is black (dark color), the light for recognizing the opening pattern 4a is irradiated as compared with the case where the insulating layer 4 is white (light color), for example. There is no inconvenience that the reflected light sometimes becomes too large to be recognized by the image recognition device (due to halation or the like).

  As described above, according to the present embodiment, it is possible to obtain a wiring board that can recognize the opening pattern 4a more reliably.

  The present invention is not limited to the embodiments described above, and various changes and improvements can be made without departing from the scope of the present invention. For example, the insulating layer 4 may be formed on the other main surface facing the one main surface of the mother substrate in the abandoned region 3.

It is a top view which shows an example of embodiment of the multiple pick-up wiring board of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Mother board 2 ... Wiring board area 3 ... Disposal area 4 ... Insulating layer 4a ... Opening pattern 5 ... Mounting part 6 ... Wiring Conductor 9 ... Multiple wiring board

Claims (2)

A mother board made of ceramic in which a plurality of wiring board areas are arranged vertically and horizontally in the center and a marginal area is formed in the outer periphery,
A plurality of wiring boards comprising an insulating layer formed on one main surface of the mother board so as to cover the abandoned area,
The insulating layer contains as a main component a ceramic component having the same composition as the ceramic component forming the mother substrate, and has an opening that exposes the surface of the mother substrate while exhibiting a color tone different from that of the ceramic forming the mother substrate. A wiring board having multiple patterns, characterized by having a pattern. 2. The multiple wiring substrate according to claim 1, wherein the insulating layer is formed on the one main surface and over the entire abandoned region excluding a portion where the opening pattern is formed.

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