JP4651686B2 - Electronic component mounting package manufacturing method and electronic device manufacturing method - Google Patents

Description

  The present invention relates to an electronic component mounting package for mounting an electronic component such as a semiconductor element or a piezoelectric vibrator on a wiring board, and an electronic device that is hermetically sealed by covering the electronic component with a resin sealing material. It relates to a manufacturing method.

2. Description of the Related Art Conventionally, as a resin-sealed small electronic device mounted on an information processing device such as a computer or a communication terminal device such as a mobile phone, for example, a cross-sectional view shown in FIG. 5 is known.
This electronic device has a plurality of notches 44 extending between the upper and lower surfaces on the side surface of an insulating substrate made of an electrically insulating material such as an aluminum oxide sintered body, and is led out from the upper surface to the lower surface via the notches 44. In addition, a wiring board 41 having a square plate shape with a size of several square mm is formed, on which a plurality of wiring layers 45 made of a metallized layer of a metal powder such as tungsten (W) or molybdenum (Mo) are formed. Then, an electronic component 42 such as a semiconductor element is mounted on the wiring board 41 so that each electrode thereof is electrically connected to the corresponding wiring layer 45 via the conductor bump 46, and the upper surface of the wiring board 41. An electronic device in which the electronic component 42 is hermetically sealed is manufactured by fixing a resin sealing material 43 made of a resin such as an epoxy resin so as to cover the electronic component 42 at the center.

  However, in this conventional electronic device, when the liquid resin sealing material 43 is dropped so as to cover the electronic component 42, a part of the liquid resin sealing material 43 is in the notch 44 due to its fluidity. It is easy to flow into. When the resin sealing material 43 flows into the notch 44, the resin sealing material 43 covers the wiring layer 45 deposited in the notch 44. As a result, when the electronic device is mounted on the external electric circuit board, a three-dimensional solder pool (so-called meniscus) is good between the wiring layer 45 in the notch 44 and the connection conductor of the external electric circuit board. In other words, the electronic device cannot be firmly mounted on the external electric circuit board.

  Therefore, the applicant of the present application has proposed an electronic device as shown in a sectional view in FIG. 3 (see Patent Document 1 below). That is, the side surface of the lower insulating layer 21b has a notch portion 24 whose upper end is closed by the upper insulating layer 21a, and W or Mo led out from the upper surface to the lower surface through the inside and the inner surface of the notch portion 24. A wiring substrate 25 having a metal layer made of a metal powder such as a metal layer is attached, and an electronic component 22 is electrically connected to the wiring layer 25 corresponding to each electrode via conductor bumps 26 on the upper surface thereof. The electronic device is mounted so as to be connected to the resin, and the resin sealing material 23 is fixed so as to cover the electronic component 22.

  According to this electronic device, since the upper end of the notch 24 is blocked by the upper insulating layer 21a, the resin sealing material 23 flows into the notch 24 and is deposited in the notch 24. The layer 25 is never covered with the resin sealing material 23. As a result, when the electronic device is mounted on the external electric circuit board, the solder pool is three-dimensionally favorably formed between the wiring layer 25 in the notch 24 and the connection conductor of the external electric circuit board. The electronic device is mounted very firmly on the external electric circuit board.

  Such a conventional electronic device has a large number of electronic devices integrated vertically and horizontally as shown in a cross-sectional view in FIG. 4 in order to facilitate handling during manufacture and to increase manufacturing efficiency. It is manufactured by a multi-cavity manufacturing method that is configured to be manufactured in an array.

  First, a large number of wiring board regions 31 to be the wiring board 21 are divided by dividing lines 32 indicated by imaginary lines and integrally formed vertically and horizontally, and the lower insulating layer 30b is penetrated on the dividing lines 32. A plurality of wiring layers 25 led out from the upper surface of each wiring board region 31 to the inner surface and the inner surface of the hole 33 to the lower surface are formed by forming a notch hole 33 whose upper end is blocked by the upper insulating layer 30a. A mother substrate 30 formed by depositing is prepared. Next, the electronic component 22 is mounted on each wiring board region 31 of the mother board 30 so that each electrode is electrically connected to the corresponding wiring layer 25, and all the wiring boards on the mother board 30 are mounted. A liquid resin sealing material 34 is applied by screen printing so as to cover the electronic component 22 in the region 31. Thereafter, the resin sealing material 34 is cured and fixed, and finally, the mother board 30 is divided along the dividing lines 32, whereby a large number of electronic devices are manufactured simultaneously and collectively.

  In addition, the plurality of wiring layers 25 of the mother board 30 have plating metal layers such as a nickel plating layer and a gold plating layer deposited on the exposed surfaces thereof by an electrolytic plating method or an electroless plating method. 25 corrosion can be effectively prevented.

A solder pool is formed in a three-dimensionally good manner between the wiring layer 25 in the notch 24 of the electronic device obtained by the division and the connection conductor of the external electric circuit board, and the electronic device is connected to the external electric device. It can be mounted very firmly on the circuit board.
JP 2001-356064 A

  However, in the electronic device disclosed in Patent Document 1 described above, the base substrate 30 is immersed in a plating solution, and a plating metal layer such as a nickel plating layer and a gold plating layer is applied to the exposed surface of the wiring layer 25 by an electrolytic plating method or electroless method. In this case, the hole 33 for the notch is on the dividing line 32 that divides each wiring board region 31 and the upper end is blocked by the upper insulating layer 30a. In the upper end portion of the wiring layer 25 deposited on the inner surface of the hole 33, air cannot escape and air is easily trapped. Therefore, the upper end portion of the wiring layer 25 where the air pool is generated is the plating solution. Cannot soak inside. As a result, the corrosion of the wiring layer 25 in the cutout 24 of the electronic device cannot be prevented, and the flowability of the solder and the bonding strength of the solder are also reduced due to the corrosion. It becomes impossible to satisfactorily form a solder meniscus between 25 and the connecting conductor of the external electric circuit board. As a result, the electronic device cannot be firmly mounted on the external electric circuit board.

  Accordingly, the present invention has been completed in view of such conventional problems, and the object thereof is to satisfactorily attach a plated metal layer to a wiring layer in a notch portion of a wiring board so that the wiring layer is connected to an external electric circuit. Another object of the present invention is to provide an electronic component mounting package and an electronic device that can be securely and firmly connected to each other.

  The method for manufacturing an electronic component mounting package according to the present invention includes a mounting portion on which an electronic component is mounted and a plurality of wiring board regions on which wiring layers to which electrodes of the electronic component are connected are arranged, and a lower surface and A non-through hole for a notch is formed on a parting line of the wiring board region adjacent to each other, is electrically connected to the wiring layer, and is formed partway from the lower end of the inner surface of the hole toward the upper side. Preparing a mother board for obtaining a package for mounting a large number of electronic components having the wiring board region and the notch by dividing along the dividing line, And a step of forming a plated metal layer on the surface of the conductor layer.

  In the method for manufacturing an electronic device according to the present invention, a plurality of wiring board regions in which a mounting portion on which an electronic component is mounted and a wiring layer to which an electrode of the electronic component is connected are formed are arranged, and the lower surface and adjacent to each other. A side conductor that has a non-through hole for a notch on the dividing line of the wiring board region, is electrically connected to the wiring layer, and is formed partway from the lower end of the inner surface of the hole toward the upper side. A step of preparing a mother board having a layer, a step of forming a plated metal layer on the surface of the side conductor layer, and mounting electronic components on the mounting portions of the multiple wiring board regions on the upper surface of the mother board, respectively. A step of applying a resin sealing material so as to cover the plurality of wiring substrate regions and the electronic component on the upper surface of the mother substrate, and dividing the mother substrate and the resin sealing material along the dividing line. Characterized by sequentially and a step of obtaining a large number of electronic devices having the notch by the.

  Preferably, in the electronic device manufacturing method of the present invention, in the electronic device manufacturing method of the present invention, the resin sealing material covers a portion corresponding to the non-through hole on the upper surface of the mother board. Features.

  In the present invention, even when a plated metal layer is deposited on the inner surface of a hole for a notch in the state of a mother board in order to produce a large number of electronic component mounting packages or electronic devices, an air pocket is generated. Since the side conductor layer is not attached to the upper end portion of the hole for the notch which is easy to be formed, it is possible to effectively prevent corrosion without forming the plated metal layer on the upper end portion of the side conductor layer.

  An electronic component mounting package (hereinafter also referred to as a package) and an electronic device manufacturing method of the present invention will be described in detail below. FIG. 1 is a cross-sectional view showing an embodiment of a package manufactured according to the present invention. In FIG. 1, 1 is a wiring board, 2 is an electronic component made of a semiconductor element such as an IC or LSI, and 3 is a resin seal. Stop material.

  The package includes a mounting portion 7 on which the electronic component 2 is mounted on the main surface of the wiring substrate 1 and a wiring layer 5 to which the electrodes of the electronic component 2 are connected, and at least corners and side surfaces of the wiring substrate 1. On the other hand, a side conductor layer 5a electrically connected to the wiring layer 5 is formed in a notch 4 formed from the lower surface to the upper surface of the wiring board 1, and the notch 4 The wiring board 1 is formed halfway from the lower surface toward the upper surface, and the side conductor layer 5a is formed halfway from the lower end of the cutout portion 4 toward the upper side.

  The wiring board 1 is made of an electrically insulating material such as an aluminum oxide sintered body, an aluminum nitride sintered body, a mullite sintered body, a silicon nitride sintered body, a silicon carbide sintered body, or a glass ceramic. The upper insulating layer 1a, the intermediate insulating layer 1b, and the lower insulating layer 1c are in the form of a square plate. A plurality of notches 4 whose upper ends are closed by the insulating layer 1a are formed on the side surfaces of the insulating layers 1b and 1c.

  When this wiring board 1 is made of, for example, an aluminum oxide sintered body, a suitable organic binder, solvent, etc. are added to and mixed with raw material powders such as aluminum oxide, silicon oxide, magnesium oxide, and calcium oxide to form a slurry. This is formed into a sheet shape by a conventionally known doctor blade method, calendar roll method or the like to obtain a ceramic green sheet (ceramic raw sheet, hereinafter also referred to as a green sheet), and then the notch 4 is formed on the green sheet. The through-holes to be formed are formed by punching, and the green sheets for the insulating layers 1a to 1c for mounting the electronic component 2 are laminated, fired at a high temperature (about 1600 ° C.), and integrated. .

  The wiring board 1 supports the electronic component 2 and covers the insulating layer 1a from the upper surface to the lower surface of the insulating layer 1c via the side conductor layer 5a attached to the inside and the notch 4. A plurality of attached wiring layers 5 are formed. The wiring layer 5 functions as a conductive path for connecting each electrode of the electronic component 2 to an external electric circuit, and each electrode of the electronic component 2 is, for example, solder, gold or the like on the wiring layer 5 on the upper surface of the wiring substrate 1. It is electrically connected through a conductor bump 6 made of

  In the example of FIG. 1, the electronic component 2 has electrodes on its lower surface and each electrode and the wiring layer 5 are electrically connected via the conductor bumps 6, but the electronic component 2 has electrodes on its upper surface. Each electrode may be electrically connected to the wiring layer 5 through a bonding wire or the like.

  For the wiring layer 5 and the side conductor 5a, for example, a metal paste obtained by adding and mixing a suitable organic solvent and solvent to a metal powder such as W or Mo is preliminarily patterned in a green sheet to be the wiring substrate 1 by screen printing. In this way, the insulating layers 1a to 1c are deposited on the respective predetermined positions by printing.

  It should be noted that a metal having excellent corrosion resistance, such as nickel (Ni), gold (Au), or the like is preferably deposited on the exposed surfaces of the wiring layer 5 and the side conductor 5a in a thickness of about 1 to 20 μm. 5 and the side conductor layer 5a can be effectively prevented from being oxidized and corroded, and the connection between the wiring layer 5 and the electronic component 2 and the connection between the side conductor layer 5a and the connection conductor of the external electric circuit board can be strengthened. Can do. Therefore, on the exposed surfaces of the wiring layer 5 and the side conductor layer 5a, an Ni plating layer having a thickness of about 1 to 10 μm and an Au plating layer having a thickness of about 0.1 to 3 μm are formed by an electrolytic plating method or an electroless plating method. It is preferred that they are deposited sequentially.

  A resin sealing material 3 made of a resin such as an epoxy resin is fixed to the upper surface of the wiring board 1 so as to cover the electronic component 2 over the entire upper surface of the wiring board 1. The resin sealing material 3 functions as a protective member that hermetically seals the electronic component 2 and protects it from the external environment by being fixed on the wiring board 1 so as to cover the electronic component 2.

  As shown in the cross-sectional view of FIG. 2, the package is a multi-piece wiring in which a large number of packages are integrally arranged vertically and horizontally in order to facilitate handling during manufacturing and to increase manufacturing efficiency. Manufactured as a substrate.

  A large number of mother substrates 10 are used for electrical insulation of aluminum oxide sintered bodies, aluminum nitride sintered bodies, mullite sintered bodies, silicon nitride sintered bodies, silicon carbide sintered bodies, glass ceramics, and the like. The upper insulating layer 10a, the intermediate insulating layer 10b, and the lower insulating layer 10c made of materials are laminated. In addition, the mother board 10 has a plurality of wiring board regions 11, each of which becomes the wiring board 1, at the central portion thereof, which are divided by vertical dividing lines 12 and arranged vertically and horizontally, and an insulating layer 10 b on the dividing lines 12. , 10c and a hole 13 for a notch whose upper end is blocked by an insulating layer 10a is formed. In addition, a wiring layer 5 made of a metallized layer led out from the upper surface of each wiring board region 11 to the lower surface through a side conductor layer 5a attached to the inside and the inner surface of the hole 13 is deposited.

  When the insulating layers 10a to 10c are made of an aluminum oxide sintered body, the mother substrate 10 is prepared by adding a suitable organic binder and solvent to a raw material powder such as aluminum oxide, silicon oxide, calcium oxide, magnesium oxide and the like. This is formed into a sheet shape by a conventionally known doctor blade method to obtain three green sheets. Thereafter, these green sheets are appropriately punched and wiring layers 5, side conductor layers 5a. It is manufactured by applying and printing a metal paste containing a metal powder such as W or Mo for use and laminating it up and down and firing it at a temperature of about 1600 ° C. in a reducing atmosphere.

  It should be noted that a plating metal layer such as a nickel plating layer and a gold plating layer is applied to the exposed surface of the wiring layer 5 and the side conductor layer 5a of the mother substrate 10 by an electrolytic plating method or an electroless plating method.

  Then, the electronic component 2 is mounted on the upper surface of each wiring board region 11 of the mother board 10 and each electrode thereof is electrically connected to the corresponding wiring layer 5 through a conductor bump 6 made of, for example, solder or gold. In order to electrically connect each electrode of the electronic component 2 to the wiring layer 5 via the conductor bump 6, for example, the conductor bump 6 is attached in advance to each electrode of the electronic component 2, and the conductor bump 6 is attached to the electrode 5. A method of joining to the corresponding wiring layer 5 by welding or pressure bonding is employed.

  The wiring board regions 11 and the electronic components 2 mounted on the wiring board regions 11 on the mother board 10 are covered so as to cover, for example, epoxy resin, polyimide resin, phenol resin, bismaleimide triazine resin, etc. A liquid resin sealing material 14 made of a thermosetting resin is applied and cured.

  In order to apply the liquid resin sealing material 14 on the mother substrate 10, a nozzle capable of discharging a certain amount is arranged on the mother substrate 10, and a certain amount of nozzle is moved from the nozzle while moving the nozzle in the horizontal direction. A method of discharging the liquid resin sealing material 14 or a method of applying the liquid resin sealing material 14 onto the mother substrate 10 by a screen printing method is employed. At this time, since the upper end of the hole 13 to which the side conductor layer 5a is deposited is closed by the insulating layer 10a, the resin sealing material 14 applied on the mother substrate 10 does not flow into the hole 13. Nothing at all. At the same time, since the resin sealing material 14 is applied over the entire wiring substrate region 11 on the mother substrate 10, the resin sealing material 14 can be applied collectively on each wiring substrate region 11, and as a result, the resin sealing The workability of applying the stopper 14 is extremely simple. Moreover, in order to harden the resin sealing material 14 apply | coated on the motherboard 10, the method of hardening by the thermosetting method or the ultraviolet curing method is employ | adopted, for example.

  Finally, by dividing the mother substrate 10 and the resin sealing material 14 along the dividing line 12 using a diamond cutter or a laser cutter, the side surfaces of the intermediate insulating layer 1b and the lower insulating layer 1c are A cutout portion 4 whose upper end is blocked by the upper insulating layer 1a is formed. Further, on the upper surface of the wiring board 1 to which the wiring layer 5 led out from the upper surface to the lower surface through the side conductor layers 5a inside and in the notch portion 4 is attached, the electronic component 2 has wiring corresponding to each electrode. A large number of electronic devices mounted on the layer 5 so as to be electrically connected via the conductor bumps 6 and having the resin sealing material 3 fixed on the upper surface of the wiring board 1 so as to cover the electronic component 2 are simultaneously provided. Made intensively.

  In the package, a non-formed portion where the side conductor layer 5a is not formed is provided at the upper end portion of the notch portion 4, and the vertical length of the non-formed portion is 0.05 to 0.5 mm. preferable. If it is less than 0.05 mm, the length of the non-formed part is short, and therefore when the plated metal layer is deposited on the inner surface of the hole 13 for the notch part of the mother substrate 10, The air reservoir covers a part of the conductor layer 5a, and a situation in which the plated metal layer is not deposited on a part of the side conductor layer 5a easily occurs. If the thickness exceeds 0.5 mm, the length of the non-formed portion becomes long, so that the air reservoir does not cover a part of the side conductor 5a and the plated metal layer can be satisfactorily deposited, but the thickness of the wiring board 1 is thick. This is disadvantageous for thinning.

  The package includes a mounting portion 7 on which the electronic component 2 is mounted on the main surface of the wiring substrate 1 and a wiring layer 5 to which the electrodes of the electronic component 2 are connected, and at least corners and side surfaces of the wiring substrate 1. On the other hand, a side conductor layer 5 a electrically connected to the wiring layer 5 is formed in a cutout portion 4 formed from the lower surface to the upper surface of the wiring substrate 1. With such a structure, a good solder meniscus is formed between the side conductor layer 5a in the cutout portion 4 and the connection conductor of the external electric circuit board, and it is mounted on the external electric circuit board very firmly. Can do.

  Further, the cutout portion 4 of the package is formed partway from the lower surface to the upper surface of the wiring substrate 1, and the side conductor layer 5a is formed on the upper surface of the lower insulating layer 1c from the lower end of the cutout portion 4 to the upper side. It is formed to the position of. When such a package is manufactured as a multi-cavity wiring board, the upper end of the hole 13 is prone to air trapping when a plated metal layer is deposited on the inner surface of the hole 13 for the notch portion of the mother board 10. Since the side conductor layer 5a is not deposited on the side surface of the intermediate insulating layer 1b corresponding to the portion, it is possible to effectively prevent the side conductor layer 5a from being corroded.

  Further, the electronic device includes the package, the electronic component 2 mounted on the mounting portion 7 and electrically connected to the wiring layer 5, and the resin sealing material 3 covering the electronic component 2. A highly reliable meniscus of solder is formed between the side conductor layer 5a in the notch 4 and the connection conductor of the external electric circuit board, so that the electronic device is mounted extremely firmly on the external electric circuit board. It will be a thing.

  Note that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention.

It is sectional drawing which shows an example of embodiment about the electronic component mounting package of this invention. It is sectional drawing of the motherboard for demonstrating the manufacturing method which manufactures the electronic component mounting package of FIG. It is sectional drawing of the conventional electronic component mounting package. FIG. 4 is a cross-sectional view of a mother board for explaining a manufacturing method for producing a large number of electronic component mounting packages of FIG. 3 from a mother board. It is sectional drawing which shows the other example of the conventional electronic component mounting package.

Explanation of symbols

1: Wiring board 2: Electronic component 3: Resin encapsulant 5: Wiring layer 5a: Side conductor layer 10: Mother board 11: Wiring board area 12: Dividing line 13: Hole for notch

Claims (3)

A plurality of wiring board regions in which a mounting portion on which electronic components are mounted and wiring layers to which electrodes of the electronic components are connected are formed are arranged, and notches are formed on the lower surface and adjacent dividing lines of the wiring board regions. A non-through hole for a portion, and a side conductor layer that is electrically connected to the wiring layer and formed partway from the lower end of the inner surface of the hole toward the upper side, along the dividing line Preparing a mother board for obtaining a large number of electronic component mounting packages having the wiring board region and the cutout portion by dividing the wiring board area;
And a step of forming a plated metal layer on the surface of the side conductor layer. A plurality of wiring board regions in which a mounting portion on which electronic components are mounted and wiring layers to which electrodes of the electronic components are connected are formed are arranged, and notches are formed on the lower surface and adjacent dividing lines of the wiring board regions. Preparing a mother board having a non-through hole for a portion, electrically connected to the wiring layer, and having a side conductor layer formed partway from the lower end of the inner surface of the hole toward the upper side; ,
Forming a plated metal layer on the surface of the side conductor layer;
A step of mounting electronic components on the mounting portions of the multiple wiring board regions on the upper surface of the mother board, and a resin sealing material to cover the multiple wiring board regions and the electronic components on the upper surface of the mother board. Applying step;
And a step of sequentially obtaining a large number of electronic devices having the notches by dividing the mother substrate and the resin sealing material along the dividing line.   3. The method of manufacturing an electronic device according to claim 2, wherein the resin sealing material covers a portion corresponding to the non-through hole on the upper surface of the mother board.

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