JP4513389B2 - Multilayer wiring board and manufacturing method thereof - Google Patents

Description

  The present invention relates to a multilayer wiring board, and more particularly to a multilayer wiring board having a substrate body in which ceramic sheets are laminated and an internal conductor is built in, and a method for manufacturing the same.

  In general, a semiconductor integrated circuit (hereinafter referred to as an IC) mounted on a multilayer wiring board is a component that is vulnerable to electrostatic breakdown. Therefore, as described in Patent Document 1, an electrostatic countermeasure element is mounted on the IC. The above electrostatic charges were not applied. However, with this configuration, in the process of manufacturing the multilayer wiring board, the IC cannot be protected from static electricity after the IC is mounted until the antistatic element is mounted.

  Usually, the substrate body of the multilayer wiring board is made of a dielectric material in order to incorporate a function such as a capacitor, and its volume is several times or more that of a single IC. For this reason, the substrate body may accumulate static electricity during the manufacturing process, and the external electrode may come into contact with other conductors to discharge static electricity via the mounted IC. . At this time, an overloaded electrostatic charge is applied to the IC, and the IC is destroyed with high probability.

  In consideration of this point, in Patent Document 1, an anti-static element is built in the substrate body to form an anti-static part, so that the anti-static countermeasure is taken in advance when the IC is mounted. A measure for avoiding destruction of the IC is also disclosed.

  However, if an attempt is made to achieve the IC protection level in the finished product with only the static electricity countermeasure part built in the board body, a considerably large volume is required, and there is a problem that the downsizing of the board body, which is a recent requirement, cannot be achieved. .

  As another means for avoiding the electrostatic breakdown of the IC in the manufacturing process, Patent Document 2 discloses a method of mounting the IC in such a state that the electrostatic protection element is first mounted on the substrate body and the static electricity countermeasure is taken. Is described.

However, if the anti-static element is first passed through the solder reflow and mounted on the substrate body, the IC mounting portion is also solder reflowed. Generally, an IC is electrically connected to a land on a substrate body by wire bonding or a solder bump, but once the land passes through the solder reflow, the smoothness is impaired due to the solder, and the IC This causes a problem that the mounting becomes impossible.
JP 2000-349558 A JP 11-340412 A

  Accordingly, an object of the present invention is to avoid the enlargement of the substrate body as much as possible, and to protect the protected element mounted on the substrate body to some extent in the manufacturing process, and to mount the protected element for the countermeasure against static electricity It is an object of the present invention to provide a multilayer wiring board and a method for manufacturing the same.

In order to achieve the above object, the first invention provides:
(A) In order to prevent a protected element from being destroyed by static electricity by mounting a protected element on a substrate body in which ceramic sheets are laminated and incorporating an internal conductor, and being electrically connected to the protected element A multilayer wiring board with a static electricity countermeasure part
(B) The static electricity countermeasure unit is mounted on the substrate body to generate a capacitance component, an inductance component and / or a resistance component, and is provided inside the substrate body to provide a capacitance component, an inductance component and / or Or equipped with an anti-static circuit that generates a resistance component ,
(C) A first land and a second land on which the protected element and the anti-static element are mounted are formed on the surface of the substrate body, and the anti-static circuit includes the first land. And a signal path connecting the second land and the second land ,
It is characterized by.

  According to the multilayer wiring board according to the first aspect of the present invention, an overload electrostatic charge is applied to the protected element by the electrostatic countermeasure element externally attached to the substrate body and the electrostatic countermeasure circuit built in the substrate body in advance. To prevent being done at a sufficient level. Since the anti-static circuit works in cooperation with the anti-static element and exhibits an anti-static effect, it needs only a small volume, and the size of the substrate body can be avoided as much as possible. This electrostatic protection circuit prevents a certain level of overload electrostatic charge from being applied to the protected element, although not at a complete level, in the manufacturing process after the protected element is mounted. In a manufacturing process, a temporary standard required for an antistatic effect in an antistatic circuit is a capacitance component of 3 pF or more and an inductance component of 3 nH or more.

  On the other hand, it is not necessary to first mount the anti-static element on the board body (through the solder reflow), and the land for mounting the protected element loses smoothness due to the solder reflow for the anti-static element. Therefore, mounting of the protected element is not hindered.

  In addition, a circuit that generates a capacitance component of the anti-static element may be connected to the anti-static element in either a parallel or series manner, and a circuit that generates the inductance component is connected in either a parallel or series manner. It may be.

  Of course, the static electricity countermeasure circuit may generate a component that constitutes a part of the capacitance component, inductance component, and / or resistance component of the static electricity countermeasure portion.

A method of manufacturing a multilayer wiring board according to the second invention is as follows:
( D ) In order to prevent the protected element from being destroyed by static electricity by mounting the protected element on the substrate body in which the ceramic sheets are laminated and incorporating the internal conductor, and being electrically connected to the protected element. A method for manufacturing a multilayer wiring board having a static electricity countermeasure part of
First land and the capacitance component, the second land for mounting the ESD protection device that causes an inductance component and / or a resistance component is formed on the surface of the laminate for implementing (e) the protected element together, the capacitive component, as electrostatic protection circuit to generate an inductance component and / or the resistance component is formed on the signal path connecting the inside Oite first lands and the second lands of the stack A first step of obtaining a laminate by laminating ceramic green sheets on which a conductor pattern is formed;
( F ) a second step of firing the laminate to obtain a substrate body;
(G) a third step of electrically connecting said at predetermined positions of the substrate body provided with the protected device to the first land,
(H) a fourth step of reflow soldering to the second land of the ESD protection device is provided at a predetermined position of the substrate body,
It is provided with.

  In the manufacturing method according to the second invention, the multilayer wiring board according to the first invention having the above-mentioned advantages can be obtained. In particular, the protected element is first mounted in the third step, and then the electrostatic protection element is mounted on the substrate body in the fourth step. In other words, the land for mounting the protected element is an electrostatic protection element. Since the smoothness is not lost by the solder reflow, mounting of the protected element is not hindered.

  Hereinafter, embodiments of a multilayer wiring board and a method for manufacturing the same according to the present invention will be described with reference to the accompanying drawings.

(Structure of multilayer wiring board, see Fig. 1)
FIG. 1 shows an example of a multilayer wiring board according to the present invention. The multilayer wiring board 1 includes a plurality of ceramic sheets stacked and a protected element (IC) 30 in a cavity 3 of a substrate body 2 that includes internal conductors 11, 12, 13, 14, 15, 16, 17, 18. Is sealed with resin 4 and is electrically connected to the protected element 30 to prevent the protected element 30 from being destroyed by static electricity (an antistatic element 35 and an electrostatic And a countermeasure circuit 36). Furthermore, external electrodes 37 and 37 are formed at both lower portions of the substrate body 2.

  The inner conductors 11, 12, and 13 are formed by printing a conductive paste on a dielectric ceramic sheet, and the inner conductors 11 and 12 constitute a static electricity countermeasure circuit 36 that generates a capacitance component. The inner conductors 14 to 18 are via holes that penetrate the ceramic sheet.

  The antistatic element 35 is soldered to lands 21 and 22 formed on the upper surface of the substrate body 2.

  The protected element (IC) 30 is fixed to the land 23 formed in the cavity 3 by an adhesive (not shown), and the lands 24 and 25 formed in the stepped portion of the cavity 3 via wires 31 and 32. Bonded. Note that solder bumps may be used instead of the adhesive. However, mounting an IC with solder bumps is technically difficult, and reflow must be passed twice, so fixing with an adhesive is preferable.

  By the way, each of the static electricity countermeasure element 35 and the static electricity countermeasure circuit 36 may be one element or circuit (see FIGS. 2 to 7), or may be composed of two or more elements or circuits (see FIG. 2). FIG. 8 and FIG. 9). In addition, the types of the element 35 and the circuit 36 can be arbitrarily combined with those that generate a capacitance component, an inductance component, or a resistance component so as to have a function of preventing electrostatic breakdown.

  In addition, the marking for showing a production month etc. may be formed in the upper surface or lower surface of the board | substrate body 2 as a non-through-hole which does not reach an internal conductor with a laser.

  The multilayer wiring board 1 having the above configuration is manufactured through the following steps.

  First, the laminated body used as the board | substrate body 2 is obtained. In this laminated body, lands 23, 24, and 25 for mounting the protected element 30 and lands 21 and 22 for mounting the antistatic element 35 are formed on the surface of the laminated body, and an antistatic circuit 36 ( Further, ceramic green sheets on which conductor patterns for forming the inner conductors 13 to 18 are formed are laminated and pressure-bonded so that the inner conductors 11 and 12) are formed inside the laminated body.

  Next, the laminate is fired to obtain the substrate body 2. Thereafter, the protected element 30 is provided in the cavity 3 of the substrate body 2 and is electrically connected to the land 23 by an adhesive and to the lands 24 and 25 by wire bonding. Further, an antistatic element 35 is provided on the upper surface of the substrate body 2 and mounted on the lands 21 and 22 by reflow soldering.

(Equivalent circuit of static electricity countermeasure part, see Fig. 2 to Fig. 9)
In the first example shown in FIG. 2, the antistatic element 35 and the antistatic circuit 36 are each configured as a capacitor having a capacitance component and are connected in parallel to each other. One end of the antistatic element 35 and the antistatic circuit 36 is connected to the drain of the protected element 30. The antistatic element 35 is mounted on the lands 21 and 22.

  In the second example shown in FIG. 3, the anti-static element 35 and the anti-static circuit 36 are each configured as a capacitor having a capacitance component and are connected in parallel to each other. One end of the antistatic element 35 and the antistatic circuit 36 is connected to the gate of the protected element 30. The antistatic element 35 is mounted on the lands 21 and 22.

  In the third example shown in FIG. 4, the antistatic element 35 and the antistatic circuit 36 are each configured as a capacitor having a capacitance component and are connected in parallel to each other. One end of the antistatic element 35 and the antistatic circuit 36 is connected to the gate of the protected element 30. The antistatic element 35 is mounted on the lands 21 and 22.

  In the fourth example shown in FIG. 5, the static electricity countermeasure element 35 is configured as a resistor having a resistance component, and the static electricity countermeasure circuit 36 is configured as a capacitor having a capacitance component, and is connected in parallel to each other. One end of the antistatic element 35 and the antistatic circuit 36 is connected to the gate of the protected element 30. The antistatic element 35 is mounted on the lands 21 and 22.

  In the fifth example shown in FIG. 6, the static electricity countermeasure element 35 is configured as a coil having an inductance component, and the static electricity countermeasure circuit 36 is configured as a capacitor having a capacitance component, and is connected in series with each other. One end of the static electricity countermeasure circuit 36 is connected to the gate of the protected element 30. The antistatic element 35 is mounted on the lands 21 and 22.

  In the sixth example shown in FIG. 7, the anti-static element 35 and the anti-static circuit 36 are each configured as a coil having an inductance component and are connected in series with each other. One end of the static electricity countermeasure circuit 36 is connected to the gate of the protected element 30. The antistatic element 35 is mounted on the lands 21 and 22.

  In the seventh example shown in FIG. 8, the static electricity countermeasure elements 35a and 35b are configured as a capacitor having a capacitor and an inductance component having a capacitance component, and the static electricity countermeasure circuits 36a and 36b have a capacitor and an inductance component having a capacitance component. It is comprised as a provided coil. One end of the anti-static element 35 a and the anti-static circuit 36 a are connected in parallel to the gate of the protected element 30. The static electricity countermeasure element 35b and the static electricity countermeasure circuit 36b are connected in series with each other, and one end of the static electricity countermeasure circuit 36b is connected to the other end of the static electricity countermeasure element 35a and the static electricity countermeasure circuit 36a. The static electricity countermeasure elements 35a and 35b are mounted on lands 21 and 22 provided independently.

  In the eighth example shown in FIG. 9, the static electricity countermeasure elements 35a and 35b are configured as a coil having an inductance component and a capacitor having a capacitance component, and the static electricity countermeasure circuits 36a and 36b have a coil and a capacitance component having an inductance component. It is comprised as a provided capacitor. One end of the anti-static element 35 a and the anti-static circuit 36 a are connected in parallel to the gate of the protected element 30. The static electricity countermeasure element 35b and the static electricity countermeasure circuit 36b are connected in series with each other, and one end of the static electricity countermeasure circuit 36b is connected to the other end of the static electricity countermeasure element 35a and the static electricity countermeasure circuit 36a. The static electricity countermeasure elements 35a and 35b are mounted on lands 21 and 22 provided independently.

  Note that the types of the static electricity countermeasure elements 35, 35a, and 35b and the static electricity countermeasure circuits 36, 36a, and 36b are arbitrarily combined with those that generate a capacitance component, an inductance component, or a resistance component so as to have a function of preventing electrostatic breakdown. be able to.

  That is, in the present invention, the static electricity countermeasure unit is provided inside the board body 2 and the static electricity countermeasure elements 35, 35 a, and 35 b that are mounted on the board body 2 to generate a capacitance component, an inductance component, and / or a resistance component. There are provided anti-static circuits 36, 36a, 36b for generating a capacitance component, an inductance component and / or a resistance component.

  In the multilayer wiring board 1 provided with the above various equivalent circuits, the anti-static elements 35, 35a, 35b mounted on the board body 2 and the anti-static circuits 36, 36a, 36b built in the board body 2 in advance. Therefore, it is possible to prevent an overload electrostatic charge from being applied to the protected element 30 at a sufficient level.

  The static electricity countermeasure circuits 36, 36 a, 36 b need only a small volume in order to exhibit the static electricity countermeasure effect in cooperation with the static electricity countermeasure elements 35, 35 a, 35 b, and can avoid the enlargement of the substrate body 2 as much as possible. The static electricity countermeasure circuits 36, 36 a, and 36 b are configured to apply a certain level of overload electrostatic charge to the protected element 30 in the manufacturing process after the protected element 30 is mounted. To prevent.

  On the other hand, it is not necessary to mount the anti-static elements 35, 35a, and 35b on the board body 2 first (pass the solder reflow) first, and as described in the manufacturing method, the board body 2 is first covered with the protected element. 30, and then the electrostatic countermeasure elements 35, 35 a, 35 b are mounted on the substrate body 2, and the lands 23, 24, 25 for mounting the protected element 30 are for the electrostatic countermeasure elements 35, 35 a, 35 b. The solder reflow does not lose smoothness, and mounting of the protected element 30 is not hindered.

(Other examples)
The multilayer wiring board and the manufacturing method thereof according to the present invention are not limited to the above-described embodiments, and various modifications can be made within the scope of the gist.

  For example, the configuration of the substrate body, the types of various elements incorporated in the substrate body, the shape of the internal conductor, and the like are arbitrary. Various protected elements can be mounted, and various combinations of antistatic elements and antistatic circuits can be employed.

  In particular, as a relationship between the anti-static element and the anti-static circuit in the anti-static unit, one type of component (for example, a capacitive component) may be configured by both, or another component (for example, the anti-static unit by both) May be a capacitance component, and the anti-static circuit may constitute an inductance component). The antistatic element may be mounted in a cavity formed in the substrate body.

It is sectional drawing which shows an example of the multilayer wiring board which concerns on this invention. It is a block diagram which shows the 1st example (equivalent circuit) of the static electricity countermeasure part provided in the said multilayer wiring board. It is a block diagram which shows the 2nd example (equivalent circuit) of the static electricity countermeasure part provided in the said multilayer wiring board. It is a block diagram which shows the 3rd example (equivalent circuit) of the static electricity countermeasure part provided in the said multilayer wiring board. It is a block diagram which shows the 4th example (equivalent circuit) of the static electricity countermeasure part provided in the said multilayer wiring board. It is a block diagram which shows the 5th example (equivalent circuit) of the static electricity countermeasure part provided in the said multilayer wiring board. It is a block diagram which shows the 6th example (equivalent circuit) of the static electricity countermeasure part provided in the said multilayer wiring board. It is a block diagram which shows the 7th example (equivalent circuit) of the static electricity countermeasure part provided in the said multilayer wiring board. It is a block diagram which shows the 8th example (equivalent circuit) of the static electricity countermeasure part provided in the said multilayer wiring board.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Multilayer wiring board 2 ... Board | substrate body 3 ... Cavity 11-18 ... Internal conductor 21-25 ... Land 30 ... Protected element (IC)
31, 32 ... Wires 35, 35a, 35b ... Electrostatic countermeasure elements 36, 36a, 36b ... Electrostatic countermeasure circuits

Claims (5)

Static electricity countermeasures for preventing the element to be protected from being destroyed by static electricity by mounting the element to be protected on the substrate body including the ceramic sheet and the internal conductor built therein. A multilayer wiring board having a portion,
The static electricity countermeasure unit is mounted on the substrate body to generate a capacitance component, an inductance component and / or a resistance component, and is provided inside the substrate body to have a capacitance component, an inductance component and / or a resistance component. and a static electricity protection circuit to cause,
A first land and a second land on which the protected element and the anti-static element are respectively mounted are formed on the surface of the substrate body, and the anti-static circuit includes the first land and the second land. A multilayer wiring board formed on a signal path that connects two lands . The static electricity countermeasure circuit generates a capacitance component or an inductance component, and a circuit that generates a capacitance component of the static electricity prevention circuit is connected in parallel to the static electricity countermeasure element, and a circuit that generates the inductance component is connected in series. The multilayer wiring board according to claim 1, wherein the multilayer wiring board is connected to the wiring board. The static electricity countermeasure circuit generates a capacitance component or an inductance component, and a circuit that generates a capacitance component of the static electricity countermeasure circuit is connected in series to the static electricity countermeasure element, and a circuit that generates an inductance component is connected in parallel. The multilayer wiring board according to claim 1, wherein the multilayer wiring board is connected to the wiring board. The ESD protection circuit, the capacitance component of the ESD protection portion, claim 1, characterized in that to produce a component that constitutes part of the inductance component and / or resistive component, claim 2 or claim 3 multilayer wiring substrate according to. Static electricity countermeasures for preventing the element to be protected from being destroyed by static electricity by mounting the element to be protected on the substrate body including the laminated ceramic sheets and incorporating the internal conductor. A method for manufacturing a multilayer wiring board having a portion,
First land and the capacitance component for implementing the protected device, with the second land for mounting the ESD protection device that causes an inductance component and / or a resistance component is formed on the surface of the laminated body, volume component, as electrostatic protection circuit to generate an inductance component and / or the resistance component is formed on the signal path connecting the inside Oite first land and the second land of the laminate, the conductor pattern A first step of obtaining a laminate by laminating ceramic green sheets formed with
A second step of firing the laminate to obtain a substrate body;
A third step of electrically connecting the first land and wire bonding the provided the protected element in a predetermined position of the substrate body,
A fourth step of reflow soldering to the second land of the ESD protection device is provided at a predetermined position of the substrate body,
A method of manufacturing a multilayer wiring board, comprising:

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