JP2001237363A - Circuit device and mounting substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that the thickness of support substrates of originally unnecessary printed board, a ceramic substrate and a flexible sheet enlarges a circuit device on which circuit elements are mounted. SOLUTION: The separation groove 54 of a bent side is formed in conductive foil 60 and circuit elements are mounted. Insulating resin 50 is bonded and inverted with conductive foil 60 as a support substrate. Conductive foil is polished with insulating resin 50 as the support substrate and is separated as a conductive path. Thus, a thin circuit device where the conductive path 51 and circuit element 52 are supported by insulating resin 50 can be realized without adopting the support substrate. Since the side of the conductive path is bent, the lack of the conductive path can be prevented. Since the conductive path is exposed, an external circuit element 1 can be mounted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit device and a mounting substrate, and more particularly to a thin circuit device and a mounting substrate which do not require a supporting substrate.

[0002]

2. Description of the Related Art Conventionally, a circuit device set in an electronic device is employed in a cellular phone, a portable computer, and the like, and therefore, a reduction in size, thickness, and weight is required.

For example, a semiconductor device will be described as an example of a circuit device. As a general semiconductor device, there is a package type semiconductor device sealed with a conventional transfer mold. This semiconductor device 1 is, as shown in FIG.
It is mounted on the printed circuit board PS.

In the package type semiconductor device 1, the periphery of a semiconductor chip 2 is covered with a resin layer 3.
The lead terminal 4 for external connection is led out from the side part of FIG.

However, this package type semiconductor device 1 has
The lead terminals 4 were outside the resin layer 3, and the overall size was large, and the size, thickness and weight were not satisfied.

Therefore, various companies have competed to develop various structures in order to realize miniaturization, thinning and weight reduction, and recently called a CSP (chip size package), a wafer scale CSP equivalent to the chip size. Alternatively, a CSP having a size slightly larger than the chip size has been developed.

FIG. 27 shows a case where a glass epoxy substrate 5 is used as a support substrate, and the CS is slightly larger than the chip size.
It shows P6. Here, the glass epoxy substrate 5
It is assumed that the transistor chip T is mounted on the semiconductor device.

A first electrode 7, a second electrode 8, and a die pad 9 are formed on the surface of the glass epoxy substrate 5, and a first back electrode 10 and a second back electrode 11 are formed on the back surface.
Are formed. And, through the through hole TH,
The first electrode 7 and the first back electrode 10 are electrically connected, and the second electrode 8 and the second back electrode 11 are electrically connected. The bare transistor chip T is fixed to the die pad 9, and the emitter electrode of the transistor and the first electrode 7 are fixed.
Are connected via the thin metal wire 12, and the base electrode of the transistor and the second electrode 8 are connected via the thin metal wire 12. Further, a resin layer 13 is provided on the glass epoxy substrate 5 so as to cover the transistor chip T.

Although the CSP 6 employs the glass epoxy substrate 5, unlike the wafer scale CSP, the structure extending from the chip T to the back surface electrodes 10 and 11 for external connection is simple, and the CSP 6 can be manufactured at low cost. Have.

The CSP 6 is mounted on a printed circuit board PS as shown in FIG. In the printed circuit board PS,
The CSP is provided with electrodes and wiring constituting an electric circuit.
6. The package type semiconductor device 1, the chip resistor CR or the chip capacitor CC and the like are electrically connected and fixed.

The circuit constituted by the printed circuit board module is mounted in various sets.

Next, a method of manufacturing the CSP 6 will be described with reference to FIG.
This will be described with reference to FIG. In FIG. 29, reference is made to a flow chart entitled "Galaepoe / flexible substrate" at the center.

First, a glass epoxy substrate 5 is prepared as a substrate (supporting substrate), and C
The u foils 20 and 21 are pressed. (See FIG. 28A above.) Subsequently, the first electrode 7, the second electrode 8, the die pad 9,
The Cu foils 20, 21 corresponding to the first back electrode 10 and the second back electrode 11 are coated with an etching resistant resist 22, and the Cu foils 20, 21 are patterned by etching. The patterning may be performed separately on the front and back sides (see FIG. 28B). Subsequently, after removing the resist 22, a hole for a through hole TH is formed using a drill or a laser on the glass epoxy substrate. 5 and plating this hole to form a through hole TH. The first through hole TH
The electrode 7 and the first back electrode 10 are electrically connected, and the second electrode 8 and the second back electrode 10 are electrically connected. (Refer to FIG. 28C.) Further, although not shown in the drawing, the first electrode 7 and the second electrode 8 serving as bonding posts are plated with Ni, and the die pad 9 serving as a die bonding post is formed with Au.
Plating is performed, and the transistor chip T is die-bonded.

Finally, the emitter electrode of the transistor chip T and the first electrode 7, and the base electrode and the second electrode 8 of the transistor chip T are connected via a thin metal wire 12 and covered with a resin layer 13. (See FIG. 28D above.) Then, if necessary, dicing is performed to separate individual electric elements. In FIG. 28, the glass epoxy substrate 5
Although only one transistor chip T is provided, a large number of transistor chips T are provided in a matrix. Therefore, they are finally separated by a dicing device.

By the above manufacturing method, a CSP type electric element using the support substrate 5 is completed. This manufacturing method
The same applies to the case where a flexible sheet is used as the support substrate.

On the other hand, a manufacturing method using a ceramic substrate is shown in the flow on the left side of FIG. After preparing a ceramic substrate that is a support substrate, a through hole is formed, and then
The front and back electrodes are printed and sintered using conductive paste. After that, until the resin layer of the manufacturing method of FIG. 28 is covered, the manufacturing method is the same as that of FIG. 28. There is a problem that cannot be molded using. For this reason, after sealing resin is potted and cured, it is polished to flatten the sealing resin, and finally separated individually using a dicing device.

[0017]

In FIG. 27, a transistor chip T, connecting means 7 to 12 and a resin layer 13 are shown.
Is a necessary component for electrical connection to the outside and protection of the transistor, but it is difficult to provide an electric circuit element that realizes reduction in size, thickness, and weight with only these components. Was.

Further, the glass epoxy substrate 5 serving as the support substrate is essentially unnecessary as described above. However, in the manufacturing method, the glass epoxy substrate 5 is used as a supporting substrate for bonding the electrodes, and the glass epoxy substrate 5 cannot be eliminated. For this reason, the use of the glass epoxy substrate 5 increases the cost, and further, the glass epoxy substrate 5 is thick, so that it becomes thick as a circuit element, and there is a limit in reducing the size, thickness, and weight.

Further, in the case of a glass epoxy substrate or a ceramic substrate, a through-hole forming step for connecting electrodes on both sides is indispensable, and there is a problem that the manufacturing process becomes long.

When the CSP 6 is mounted on a printed circuit board PS as shown in FIG.
The thickness of the support substrate of SP6 is added, and the printed circuit board module becomes thick. Furthermore, when the circuit element 1 and the chip capacitor CC are mounted on the back surface of the printed circuit board PS, the thickness of the mounted circuit elements is also added, resulting in a thicker printed circuit board module. Therefore, there is a problem that a set (electronic device) on which the printed circuit board module is mounted is enlarged.

[0021]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned many problems, and firstly, a plurality of conductive paths electrically separated by a separation groove and a desired conductive path above the conductive path. A circuit element fixed to the insulating element; an insulating resin that covers the circuit element and is filled in the separation groove between the conductive paths to expose and support the back surface of the conductive path integrally; This problem is solved by providing a fixed external circuit element, and bending the side surface of the conductive path to fit the insulating resin.

Second, a plurality of conductive paths electrically separated by the separation groove, a desired circuit element fixed on the conductive path, and an electrode of the circuit element and another conductive path are connected. A connecting means, an insulating resin that covers the circuit element and is filled in the separation groove between the conductive paths to expose and support the back surface of the conductive path integrally; and an outer resin fixed to the back surface of the conductive path. The problem is solved by providing a mounting circuit element, and bending the side surface of the conductive path to fit the insulating resin.

Third, a plurality of conductive paths electrically separated by a separation groove, a plurality of circuit elements fixed on the desired conductive path, a desired electrode of the circuit element, and other conductive paths A connecting means for connecting the circuit element, an insulating resin that covers the circuit element and is filled in the separation groove between the conductive paths to expose and support the back surface of the conductive path integrally; This problem is solved by providing a fixed external circuit element, and bending the side surface of the conductive path to fit the insulating resin.

The circuit device excluding the external components can minimize the number of components and can realize a circuit device in which functions are further added by the external components since the back surface is exposed.

Fourth, the circuit element is a semiconductor bare chip, chip circuit component, package type semiconductor device, CSP
The problem is solved by either or both of the above.

Fifth, the problem can be solved by forming the connection means from a bonding thin wire or a brazing material.

Sixth, the problem is solved by making the back surface of the conductive path and the back surface of the insulating resin filled between the separation grooves substantially flat.

Since the conductive path and the insulating resin form the same surface, the mounted external circuit element can be shifted without hitting the side surface of the conductive path. In particular, it is possible to reposition the externally mounted circuit elements that are mounted in a displaced manner while being shifted in the horizontal direction. If the brazing material is melted after mounting the external circuit element, the mounted external circuit element will attempt to return to the top of the conductive path by the surface tension of the melted brazing material, and The relocation is done by itself.

Seventh, the problem is solved by using the conductive path as an electrode, a bonding pad, a die pad, a wiring or a connector.

Eighth, a plurality of conductive paths which are electrically separated by separating grooves and have curved side surfaces, a desired circuit element fixed to the back surface of the conductive path, An insulating resin that is filled with the insulating groove and that is filled with the insulating groove and that exposes the surface of the conductive path and integrally supports the conductive path. The problem is solved by providing a circuit element.

The present invention can be used as a mounting board having a built-in function in which circuit elements are embedded. For example, a standard circuit is built in a mounting board, and the user can mount external components for adding unique functions on the mounting board.

Ninth, the problem is solved by making the surface of the conductive path and the surface of the insulating resin filled between the separation grooves substantially flat.

As described above, external components can be easily shifted, and position adjustment can be easily realized.

Tenthly, the problem is solved by making the surface of the conductive path a bonding pad or a pad for external connection.

Eleventh, the problem is solved by the fact that the melting point of the brazing material used in the mounting substrate is higher than the melting point of the brazing material used on the surface of the conductive path.

Even when the external parts are realized by the brazing material, the brazing material in the mounting board does not melt, and the circuit in the mounting board does not become defective.

[0037]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment for Explaining a Circuit Device First, the structure of a circuit device according to the present invention will be described with reference to FIG.

FIG. 1A shows that a conductive path 51 is connected to an insulating resin 50.
Is embedded, and a circuit element 52A is provided on the conductive path 51.
A circuit device 53 is shown in which 52B is fixed and the conductive path 51 is supported by the insulating resin 50. Further, an external circuit element 1 is mounted on the back surface. The side surface of the conductive path 51 has a curved structure 59. Here, the number of circuit elements may be one, or a plurality of circuit elements may be mounted. In addition, a plurality of circuit elements may constitute one IC circuit including a wiring that is one of the conductive paths.

This structure includes circuit elements indicated by reference numerals 52A and 52B, a plurality of conductive paths indicated by reference numbers 51A, 51B and 51C, and the circuit elements 52A and 52B and the conductive paths 51A and 51A.
An insulating resin 50 buried in 51B and 51C is formed, and a separation groove 54 filled with the insulating resin 50 is provided between the conductive paths 51. The conductive path 51 having the curved structure 59 is supported by the insulating resin 50.

As the insulating resin, a thermosetting resin such as an epoxy resin, or a thermoplastic resin such as a polyimide resin or polyphenylene sulfide can be used. As the insulating resin, any resin can be adopted as long as the resin can be hardened using a mold, or can be coated by dipping or coating. Further, as the conductive path 51, a conductive foil mainly composed of Cu, a conductive foil mainly composed of Al, a conductive foil composed of an alloy such as Fe-Ni, or the like can be used. Of course, other conductive materials are also possible. Particularly, a conductive material that can be etched and a conductive material that evaporates by laser are preferable.

According to the present invention, the side surface of the conductive path 51 is formed into a curved structure 59 by performing non-anisotropic etching, particularly by employing dry etching or wet etching as an etching, thereby generating an anchor effect. . As a result, a structure in which the conductive path 51 does not come off from the insulating resin 50 is realized.

The connection means of the circuit element 52 includes a thin metal wire 55A, a conductive ball made of a brazing material, a flat conductive ball, a brazing material 55B such as a solder, a conductive paste 55C such as an Ag paste, a conductive film or an anisotropic conductive material. Resin and the like. These connection means are selected depending on the type of the circuit element 52 and the mounting form of the circuit element 52. For example, in the case of a bare semiconductor element, a thin metal wire is selected for the connection between the electrode on the surface of the semiconductor element and the conductive path 51, and in the case of a CSP, a solder ball or a solder bump is selected. For the chip resistor and the chip capacitor, the solder 55B is selected. There is no problem even if a packaged circuit element, for example, a BGA or the like is mounted on the conductive path 51, and when this is adopted, solder is selected as the connection means.

The adhesion between the circuit element and the conductive path 51A is as follows.
If no electrical connection is required, an insulating adhesive is chosen,
When electrical connection is required, a conductive coating is used. Here, at least one conductive film is sufficient.

The material considered as the conductive film is A
g, Au, Pt, Pd, or the like, and is coated by deposition under a low or high vacuum such as evaporation, sputtering, or CVD, plating, or sintering of a conductive paste.

For example, Ag adheres to Au and also adheres to the brazing material. Therefore, if the Au film is coated on the back surface of the chip, the Ag film and the Au film are directly applied to the conductive path 51A.
The chip can be thermocompression-bonded, and the chip can be fixed via a brazing material such as solder. Here, the conductive film may be formed on the uppermost layer of the conductive film laminated in a plurality of layers. For example, on the conductive path 51A of Cu,
Ni coating, two layers of Au coating sequentially applied, Ni
A coating in which three layers of a coating, a Cu coating, and a solder coating are sequentially applied, and a coating in which two layers of an Ag coating and a Ni coating are sequentially applied can be formed. In addition, the kind and layered structure of these conductive films are
There are many other types, but they are omitted here.

In this circuit device, since the conductive path 51 is supported by the insulating resin 50 as a sealing resin, a supporting substrate is not required, and the conductive path 51, the circuit element 52 and the insulating resin 5 are not required.
0. This configuration is a feature of the present invention. As described in the section of the related art, the conductive path of the conventional circuit device is supported by a support substrate or supported by a lead frame, and therefore, a configuration that may be unnecessary originally is added. However, this circuit device has a feature that it is thin and inexpensive because it is composed of the minimum necessary components and does not require a support substrate.

In addition to the above configuration, there is provided an insulating resin 50 which covers the circuit element 52 and is filled in the separation groove 54 between the conductive paths 51 and integrally supported.

Separation grooves 54 are formed between the conductive paths 51 of the curved structure 59, and the insulating resin 50 is filled in the separation grooves 54, so that the conductive paths 51 can be prevented from coming off and at the same time, they can be mutually insulated. .

The circuit element 52 is covered and the conductive path 5
There is an insulating resin 50 that is filled in the separation groove 54 between the two and that only the back surface of the conductive path 51 is exposed and supported integrally.

The fact that the back surface of the conductive path is exposed is one of the features of the present invention. The back surface of the conductive path can be used for connection to the outside, and has a feature that the through hole TH of the conventional structure as shown in FIG. 27 can be omitted.

Further, when the circuit element is directly fixed to the conductive path 51 via a conductive film of brazing material, Au, Ag, or the like, the back surface of the conductive path 51 is exposed, so that the heat generated from the circuit element 52A is generated. From the conductive path 51A. In particular, the present invention is effective for a semiconductor chip capable of improving characteristics such as an increase in drive current due to heat radiation. Moreover, since the back surface of the conductive path is exposed, it can be used as an electrode for external connection. For example, an external lead EL1, a flexible sheet on which thin-film wiring is adhered, a connector, or the like can be mounted on the back surface of the conductive path 51B. Alternatively, the conductive path 51B may be used as a male connector and inserted into a female connector attached to the mounting board.

Further, in the present circuit device, the surface of the separation groove 54 and the surface of the conductive path 51 have substantially the same structure. This structure is a feature of the present invention, and as shown in FIG. 27, since no step is provided between the back electrodes 10 and 11,
It has a feature that the external circuit element 1 can be horizontally moved as it is. In particular, if the circuit device 53 has a certain size such as a printed circuit board, an external circuit element can be mounted on the conductive path 51. This is like a printed circuit board with embedded IC circuits. Meanwhile, another external connection structure will be described with reference to FIG. 1B. FIG. 1B is substantially the same as FIG. 1A, in which the external connection electrode EL2 is exposed from the insulating resin 50. According to this structure, connection with the outside via the surface of the conductive path 51B is possible. For example, it is possible to electrically connect to the mounting substrate on which the present circuit device is mounted via a thin metal wire or brazing material, and to connect external leads. Second Embodiment for Explaining Circuit Device Next, a circuit device 56 shown in FIG. 8A will be described.

In this structure, the conductive film 5 is formed on the surface of the conductive path 51.
7 are formed, and the rest is substantially the same as the structure of FIG. 1A. Therefore, the conductive film 57 will be described.

The first feature is that a conductive coating 57 is provided to prevent warpage of the conductive path and the circuit device.

In general, due to the difference in thermal expansion coefficient between the insulating resin and the conductive path material (hereinafter, referred to as a first material), the circuit device itself warps, and the conductive path is bent or peeled off. In addition, since the thermal conductivity of the conductive path 51 is superior to the thermal conductivity of the insulating resin, the conductive path 51 expands by increasing the temperature first. Therefore, by covering the second material having a smaller coefficient of thermal expansion than the first material, it is possible to prevent the conductive path from being warped or peeled off, and to prevent the circuit device from being warped.
In particular, when Cu is used as the first material, Au, Ni, Pt, or the like is preferable as the second material. The expansion coefficient of Cu is 16.7 × 10 −6 (10 −6), and A
u is 14 × 10 −6, Ni is 12.8 × 10 −6,
Pt is 8.9 × 10 −6.

The second feature is that the second material has an anchor effect. The eaves 58 are formed of the second material, and the eaves 5 are attached to the conductive paths 51.
Since 8 is embedded in the insulating resin 50, an anchor effect is generated, and a structure in which the conductive path 51 can be prevented from coming off is obtained.

In the present invention, both the curved structure 59 and the eaves 58 generate a double anchor effect to prevent the conductive path 51 from coming off. Particularly, when an IC circuit is formed in an insulating resin, a thin and bent wiring is provided. However, since this wire is also provided with an eave and a curved structure, it is possible to prevent the wire from coming off. Further, since the back surface of the conductive path 51 is exposed, the external lead EL1, a flexible sheet on which thin-film wiring is adhered, a connector, and the like can be mounted on the conductive path 51. Alternatively, the conductive path 51B may be used as a male connector and inserted into a female connector on the mounting board.

On the other hand, another external connection structure will be described with reference to FIG. 8B. FIG. 8B is substantially the same as FIG. 1B, except that an eave 58 is formed. The effect of the eaves is the same as that of FIG. 8A, and a description thereof will be omitted. According to this structure, the external connection electrode EL2 is exposed from the insulating resin 50. Due to this structure,
Connection with the outside is possible through the surface of the conductive path 51B. For example, it is possible to electrically connect to the mounting board via a thin metal wire, and it is also possible to connect external leads. The circuit device in which the transistor chip 52A and the passive element 52B are mounted has been described above as a circuit device. However, the present invention relates to a circuit device in which one semiconductor chip is sealed, as shown in FIG. 2. A circuit device 81 on which a face-down type element 80 of FIG.
Passive elements 8 such as chip resistors and chip capacitors
2 can also be implemented in a sealed circuit device 83. Furthermore,
A plurality of circuit elements, wirings for electrically connecting them, etc.
A C circuit may be configured.

The package type semiconductor device 1 is mounted as an external circuit element.
Circuit devices (electric components) such as a chip capacitor, a chip resistor, a CSP, and a BGA can also be mounted. The number is
Although limited by the size of the circuit device, at least one is mounted. First Embodiment for Explaining Method for Manufacturing Circuit Device Next, a method for manufacturing a circuit device 53 will be described with reference to FIGS. 2 to 7 and FIG.

First, as shown in FIG. 2, a sheet-shaped conductive foil 60 is prepared. The material of the conductive foil 60 is selected in consideration of the adhesion of the brazing material, the bonding property, and the plating property.
Examples of the material include a conductive foil mainly composed of Cu, Al
Or a conductive foil made of an alloy such as Fe-Ni or the like.

The thickness of the conductive foil is preferably about 10 μm to 300 μm in consideration of the later etching.
A 0 μm (2 oz) copper foil was employed. But 300μ
Basically, it is good even if it is more than m or less than 10 μm. As will be described later, it is only necessary that the separation groove 61 shallower than the thickness of the conductive foil 60 can be formed.

The sheet-like conductive foil 60 is prepared by being wound into a roll with a predetermined width, and may be conveyed to each step described later, or the conductive foil cut into a predetermined size may be used. It may be prepared and transported to each step described later.

Subsequently, there is a step of removing the conductive foil 60 excluding at least a region to be the conductive path 51 so as to be thinner than the thickness of the conductive foil 60. Then, there is a step of coating the insulating resin 50 on the separation groove 61 and the conductive foil 60 formed in this removing step.

First, as shown in FIG. 3, a photoresist PR (etching resistant mask) is formed on the Cu foil 60, and the photoresist PR is patterned so as to expose the conductive foil 60 excluding the region that becomes the conductive path 51. . And FIG. 4A
As described above, etching is performed via the photoresist PR.

The present manufacturing method is characterized in that it is non-anisotropically etched by wet etching or dry etching, and its side surfaces are rough and curved. Note that the depth of the separation groove 61 formed by etching is about 50 μm.

In the case of wet etching, ferric chloride or cupric chloride is used as an etchant, and the conductive foil is dipped in the etchant or the etchant is showered.

In particular, as shown in FIG. 4B, the etching in the horizontal direction is difficult to proceed immediately below the photoresist PR serving as an etching mask, and the deeper portion is etched widely in the horizontal direction. As shown in the figure, when the opening diameter of the separation groove 61 corresponding to the position becomes smaller from a position on the side surface of the separation groove 61 upward, the separation groove 61 has a reverse tapered structure and has a structure having an anchor structure. In addition, by employing a shower ring, etching proceeds in the depth direction and etching in the lateral direction is suppressed, so that this inversely tapered structure appears remarkably.

In the case of dry etching, anisotropy,
Non-anisotropic etching is possible. At present, it is said that it is impossible to remove Cu by reactive ion etching, but it can be removed by sputtering. Further, etching can be performed anisotropically or non-anisotropically depending on sputtering conditions. By the dry etching, a conductive path having a fine pattern can be realized as compared with the wet etching. In FIG. 3, a conductive film having corrosion resistance to an etching solution may be selectively coated instead of the photoresist.
When the conductive film is selectively applied to a portion to be a conductive path, the conductive film serves as an etching protective film, and the separation groove can be etched without employing a resist. A material that can be considered as the conductive film is, for example, Ag, Au, Pt, or Pd. Moreover, these corrosion-resistant conductive films are used for die pads,
It has the feature that it can be used as it is as a bonding pad.

For example, an Ag film adheres to Au and also adheres to a brazing material. Therefore, if the Au film is coated on the back surface of the chip, the chip can be thermocompression-bonded to the Ag film on the conductive path 51 as it is, and the chip can be fixed via a brazing material such as solder. Further, since the Au thin wire can be bonded to the Ag conductive film, wire bonding is also possible. Therefore, there is an advantage that these conductive films can be used as die pads and bonding pads as they are.

Subsequently, as shown in FIG. 5, there is a step of electrically connecting and mounting the circuit element 52 to the conductive foil 60 in which the separation groove 61 is formed.

The circuit element 52 is a semiconductor element 52A such as a transistor, a diode, or an IC chip, and a passive element 52B such as a chip capacitor or a chip resistor. Although the thickness is increased, a face-down semiconductor element such as a CSP or a BGA can be mounted.

Here, the bare transistor chip 52
A is die-bonded to the conductive path 51A, and the emitter electrode and the conductive path 51B, and the base electrode and the conductive path 51B are connected via a thin metal wire 55A. Examples of the method include ball bonding by thermocompression bonding or web bonding by ultrasonic waves. Reference numeral 52B denotes a chip capacitor or a passive element, which is fixed with a brazing material such as solder or a conductive paste 55B.

Further, as shown in FIG.
And a step of attaching the insulating resin 50 to the curved separation groove 61. This can be achieved by transfer molding, injection molding, dipping or coating. As the resin material, a thermosetting resin such as an epoxy resin can be realized by transfer molding, and a thermoplastic resin such as a polyimide resin and polyphenylene sulfide can be realized by injection molding.

In the present embodiment, the thickness of the insulating resin coated on the surface of the conductive foil 60 is adjusted so as to cover about 100 μm from the top of the circuit element. still,
This thickness can be increased or reduced in consideration of the strength of the circuit device.

The feature of this step is that the conductive foil 60 serving as the conductive path 51 becomes a supporting substrate until the insulating resin 50 is covered. Conventionally, as shown in FIG. 28, the conductive paths 7 to 11 are formed by using the support substrate 5 which is not originally required, but in the present invention, the conductive foil 60 serving as the support substrate is required as an electrode material. Material. Therefore, there is a merit that the operation can be performed while omitting the constituent materials as much as possible, and the cost can be reduced.

Since the separation grooves 61 are formed shallower than the thickness of the conductive foil, the conductive foils 60 are not individually separated as the conductive paths 51. Therefore, the sheet-shaped conductive foil 60
When molding insulating resin,
It has the feature that the work of transporting to the mold and mounting on the mold is very easy.

Further, a separation groove 61 having a curved structure 59
Is filled with the insulating resin 50, an anchor effect is generated in this portion, and peeling of the insulating resin 50 can be prevented.
Conversely, it is possible to prevent the conductive path 51 separated in a later step from coming off.

Subsequently, there is a step of chemically and / or physically removing the back surface of the conductive foil 60 and separating it as the conductive path 51. Here, the removing step is performed by polishing, grinding, etching, laser metal evaporation, or the like.

In the experiment, the entire surface was shaved by about 30 μm with a polishing device or a grinding device, and the insulating resin 50 was
Is exposed. This exposed surface is indicated by a dotted line in FIG. As a result, the conductive path 51 having a thickness of about 40 μm is formed.
And separated. Further, the entire surface of the conductive foil 60 may be wet-etched before the insulating resin 50 is exposed, and thereafter, the entire surface may be ground by a polishing or grinding device to expose the insulating resin 50 from the back surface.

As a result, a structure in which the surface of the conductive path 51 is exposed to the insulating resin 50 is obtained. As a result, the separation groove 61 is processed and becomes the separation groove 54 of FIG. (See FIG. 6 above.) Finally, a conductive material such as solder is applied to the exposed conductive path 51 as necessary, and the circuit device 53 is inverted and the external circuit element 1 is mounted as shown in FIG. Since the circuit device 53 is substantially flat, it can be mounted on a component mounting device such as a chip mounter. It can also flow to a solder reflow device. When the external circuit element is fixed via a brazing material, it is necessary to increase the melting point of the brazing material provided in the insulating resin 50. By doing so, for example, in the solder reflow step, the brazing material 55B is not melted, and disconnection and the like can be prevented.

When a conductive film is applied to the back surface of the conductive path 51, the conductive film may be formed in advance on the back surface of the conductive foil shown in FIG. In this case, the portion corresponding to the conductive path may be selectively applied. The deposition method is, for example, plating. The conductive film is preferably made of a material having resistance to etching. In this case, the conductive paths 51 can be separated only by etching without polishing.

In the present manufacturing method, only one set of the transistor and the chip resistor is mounted in the insulating resin 50. However, these may be arranged in a matrix as one unit or one of them. The circuit elements may be arranged as a unit in a matrix. Further, an IC circuit composed of a plurality of circuit elements may be arranged in a matrix as one unit. In this case, as will be described later, they are individually separated by a dicing device.

By the above manufacturing method, the insulating resin 50
A conductive circuit 51 is buried in the substrate, and a flat circuit device 56 in which the back surface of the insulating resin 50 and the back surface of the conductive path 51 match can be realized.

The feature of the present manufacturing method is that the conductive path 51 can be separated using the insulating resin 50 as a supporting substrate. The insulating resin 50 is a material necessary as a material for embedding the conductive path 51, and does not require an unnecessary support substrate 5 unlike the conventional manufacturing method of FIG. Therefore, it has a feature that it can be manufactured with a minimum amount of material and that cost reduction can be realized.

The thickness of the insulating resin from the surface of the conductive path 51 can be adjusted when the insulating resin is adhered in the previous step. Accordingly, the thickness of the circuit device 56 has a characteristic that it can be thick or thin, though it differs depending on the circuit element to be mounted. Here, 40 μm is applied to the insulating resin 50 having a thickness of 400 μm.
The circuit device has the m conductive paths 51 and the circuit elements embedded therein. (Refer to FIG. 1 above) Second Embodiment Explaining a Method of Manufacturing a Circuit Device Next, a method of manufacturing a circuit device 56 having an eave 58 will be described with reference to FIGS. 9 to 14 and FIG. Note that, except that the second material 70 serving as an eaves is adhered, the second embodiment is substantially the same as the first embodiment, and thus detailed description is omitted.

First, as shown in FIG. 9, a conductive foil 60 in which a second material 70 having a small etching rate is coated on a conductive foil 60 made of a first material is prepared.

For example, when Ni is deposited on a Cu foil, Cu and Ni can be etched at once with ferric chloride or cupric chloride or the like, and Ni becomes eaves 58 due to a difference in etching rate. Therefore, it is suitable. Thick solid line is N
i, a conductive film having a thickness of 1 to 10 μm.
m is preferable. In addition, the eaves 5
8 is easily formed.

The second material may be coated with a material which can be selectively etched with the first material. In this case, first, a film made of the second material is patterned so as to cover the formation region of the conductive path 51, and the first film is formed using this film as a mask.
This is because the eaves 58 can be formed by etching the conductive foil made of the above material. As the second material, Al, A
g, Au and the like are conceivable.

Subsequently, there is a step of removing the conductive foil 60 excluding at least a region to be the conductive path 51 so as to be thinner than the thickness of the conductive foil 60.

As shown in FIG. 10, a photoresist PR is formed on Ni 70 and Ni
The photoresist PR may be patterned so that 70 is exposed, and etching may be performed via the photoresist as shown in FIG.

As described above, when etching is performed using an etchant such as ferric chloride or cupric chloride, the eaves 58 come out as the etching proceeds because the etching rate of Ni70 is lower than the etching rate of Cu60.

The conductive foil 6 on which the separation groove 61 is formed
0, a step of mounting the circuit element 52 (FIG. 12), covering the conductive foil 60 and the separation groove 61 with an insulating resin 50, and chemically and / or physically removing the back surface of the conductive foil 60;
The step of separating as the conductive path 51 (FIG. 13), the step of forming a conductive film on the back of the conductive path and inverting the circuit device 56 (FIG. 14), and the step of mounting the external circuit element 1 to completion (FIG. 8) is the same as the previous manufacturing method, and the description thereof is omitted. Third Embodiment for explaining a method for manufacturing a circuit device Next, a method for manufacturing a discrete device and an IC device by arranging a plurality of circuit elements as one unit in a matrix and separating them individually after sealing is illustrated. This will be described with reference to FIGS. Since this manufacturing method is almost the same as the first embodiment, the same parts will be described briefly.

First, as shown in FIG. 15, a sheet-like conductive foil 60 is formed.
Prepare

The sheet-shaped conductive foil 60 is prepared by being wound into a roll with a predetermined width, and may be conveyed to each step described later, or the conductive foil cut into a predetermined size may be used. It may be prepared and transported to each step described later.

Subsequently, there is a step of removing the conductive foil 60 excluding at least a region to be the conductive path 51 so as to be thinner than the thickness of the conductive foil 60.

First, as shown in FIG.
A photoresist PR is formed, and the photoresist PR is patterned so as to expose the conductive foil 60 excluding a region serving as the conductive path 51. Then, as shown in FIG. 17, etching may be performed through the photoresist PR.

The depth of the separation groove 61 formed by etching is, for example, 50 μm, and the side surface thereof is rough, so that the adhesiveness to the insulating resin 50 is improved.

The side wall of the separation groove 61 is curved because it is anisotropically etched. For this removing step, wet etching or dry etching can be adopted. The curved structure provides a structure in which an anchor effect is generated. (For details, refer to the first embodiment for explaining a method of manufacturing a circuit device.) In FIG. 16, a conductive film having corrosion resistance to an etching solution is selectively coated instead of the photoresist PR. May be. When the conductive film is selectively applied to a portion to be a conductive path, the conductive film serves as an etching protective film, and the separation groove can be etched without employing a resist.

Subsequently, as shown in FIG. 18, there is a step of electrically connecting and mounting the circuit element 52 to the conductive foil 60 in which the separation groove 61 is formed.

The circuit element 52 is a semiconductor element such as a transistor, a diode, or an IC chip, or a passive element such as a chip capacitor or a chip resistor. Although the thickness is increased, a face-down semiconductor element such as a CSP or a BGA can be mounted.

In the figure, a bare transistor chip 52A is shown.
Are die-bonded to the conductive path 51A, the emitter electrode and the conductive path 51B, the base electrode and the conductive path 51B are connected via a thin metal wire 55A, and the chip capacitor 52B is connected via solder.

Further, as shown in FIG.
There is a step of attaching the insulating resin 50 to the separation groove 61 and the separation groove 61. This can be achieved by transfer molding, injection molding, or dipping.

In the present embodiment, the thickness of the insulating resin coated on the surface of conductive foil 60 is approximately 1 mm from the top of the circuit element.
It is adjusted so as to cover about 00 μm. This thickness can be increased or reduced in consideration of the strength of the circuit device.

The feature of this step is that, when the insulating resin 50 is coated, the conductive foil 60 serving as the conductive path 51 serves as a support substrate. Conventionally, as shown in FIG. 28, the conductive paths 7 to 11 are formed by using the support substrate 5 which is not originally required, but in the present invention, the conductive foil 60 serving as the support substrate is required as an electrode material. Material. Therefore, there is a merit that the operation can be performed while omitting the constituent materials as much as possible, and the cost can be reduced.

Since the separation grooves 61 are formed shallower than the thickness of the conductive foil, the conductive foils 60 are not individually separated as the conductive paths 51. Therefore, the sheet-shaped conductive foil 60
When molding insulating resin,
It has the feature that the work of transporting to the mold and mounting on the mold is very easy.

Subsequently, there is a step of chemically and / or physically removing the back surface of the conductive foil 60 and separating it as the conductive path 51. Here, the removing step is performed by polishing, grinding, etching, laser metal evaporation, or the like.

In the experiment, the entire surface was shaved by about 30 μm with a polishing device or a grinding device to expose the insulating resin 50. This exposed surface is indicated by a dotted line in FIG.
As a result, the conductive paths 51 having a thickness of about 40 μm are separated. Alternatively, the entire surface of the conductive foil 60 may be wet-etched before the insulating resin 50 is exposed, and thereafter, the entire surface may be ground by a polishing or grinding device to expose the insulating resin 50.

As a result, a structure in which the surface of the conductive path 51 is exposed to the insulating resin 50 is obtained.

Further, as shown in FIG.
Is coated with a conductive material such as solder.

Finally, as shown in FIG. 21, there is a step of separating each circuit element to complete a circuit device.

The separation line is indicated by an arrow and can be realized by dicing, cutting, pressing, chocolate break, or the like. When a chocolate break is adopted, a protrusion may be formed on the mold so that a groove is formed in the separation line when the insulating resin is coated.

In particular, dicing is preferred because it is frequently used in a normal semiconductor device manufacturing method and can be separated into very small sizes.

Then, the circuit device completed in FIG. 21 is inverted, and external circuit elements are mounted to complete the circuit device.

The right side of FIG. 29 shows a flow chart briefly summarizing the present invention. Preparation of Cu foil, Ag or N
The circuit device can be realized by nine steps of plating of i, etc., half etching, die bonding, wire bonding, transfer molding, removal of backside Cu foil, backside treatment of conductive paths, and dicing. Moreover, all processes can be performed in-house without supplying a supporting substrate from a manufacturer. An embodiment describing types of circuit devices and a method for mounting them.

FIG. 22 shows a face-down type circuit element 8.
9 shows a circuit device 81 in which a “0” is mounted. The circuit element 80 corresponds to a bare semiconductor chip, a CSP or BGA with a sealed surface, or the like. FIG. 23 shows a circuit device 83 on which passive elements 82 such as chip resistors and chip resistors are mounted. Since they do not require a supporting substrate, they are thin and are sealed with an insulating resin, so that they have excellent environmental resistance.

FIG. 24 illustrates the real layer structure. The circuit devices 53, 81, and 83 of the present invention described above are mounted on conductive paths 85 formed on a mounting substrate 84 such as a printed substrate, a metal substrate, or a ceramic substrate.

In particular, since the conductive path 51 A to which the back surface of the semiconductor chip 52 is fixed is thermally coupled to the conductive path 85 of the mounting board 84, heat can be radiated through the conductive path 85. When a metal substrate is used as the mounting substrate 84, the heat of the metal substrate is also helped, and the temperature of the semiconductor chip 52 can be further reduced. for that reason,
The driving capability of the semiconductor chip can be improved.

For example, power MOS, IGBT, SIT,
Transistor for driving large current, IC for driving large current (M
OS type, BIP type, Bi-CMOS type) memory element and the like are preferable.

As the metal substrate, an Al substrate, a Cu substrate, or an Fe substrate is preferable. In consideration of a short circuit with the conductive path 85, an insulating resin and / or an oxide film is formed.

FIG. 25 shows a case where the circuit device of the present invention is used as a mounting substrate 90, and the circuit device 91 and the passive element 92 of the present invention are mounted thereon. Mounting board 90
Since the exposed surface of the conductive path is flat between the semiconductor device and the circuit device 91, the insulating resin 93 is coated to prevent a short circuit.
This insulating resin 93 has only a connection portion exposed similarly to a solder resist used for a printed circuit board. According to this structure, a mounting board module in which circuit elements are embedded can be used without using a printed board.

Further, advantages of the present circuit device will be described with reference to FIG. In the conventional mounting method, a semiconductor maker forms a package type semiconductor device and a flip chip, and a set maker mounts a semiconductor device supplied by a semiconductor maker and a passive element supplied by a component maker on a printed circuit board. Then, this was assembled into a set to form an electronic device. However, in the present circuit device, the semiconductor device itself can be used as a mounting substrate, and thus the semiconductor device can be supplied to a set manufacturer as a mounting substrate module. Therefore, the set maker can omit mounting elements on the printed circuit board.

[0122]

As is apparent from the above description, according to the present invention, the circuit device is composed of the minimum necessary circuit elements, conductive paths and insulating resin, and has no waste of resources. Therefore, there is no extra component until completion, and a circuit device that can greatly reduce the cost can be realized. Further, by adjusting the coating thickness of the insulating resin and the thickness of the conductive foil, a very small, thin, and lightweight circuit device can be realized.

Since only the back surface of the conductive path is exposed from the insulating resin, an external circuit element can be mounted, and the overall circuit function can be enhanced. Also, the back surface of the conductive path can be immediately provided for connection with the outside,
There is an advantage that the back electrode and the through hole of the conventional structure as shown in FIG. 27 can be eliminated.

In addition, since the back surface of the conductive path is exposed,
Heat generated from the circuit element can be transmitted to the outside via the conductive path. In particular, this heat dissipation makes it possible to mount a power element.

Further, the present circuit device has a structure in which the surface of the separation groove and the surface of the conductive path have a flat surface substantially coincident with each other, and the circuit device itself can be horizontally moved as it is when a narrow pitch QFP is mounted. Therefore, it is extremely easy to correct the lead deviation.

Further, since the second material is formed on the front side of the conductive path, it is possible to suppress the warpage of the mounting substrate due to the difference in the coefficient of thermal expansion, particularly the warpage or peeling of the elongated wiring.

Further, a double anchor effect can be generated by the curved structure of the side surface of the conductive path and the eaves attached to the conductive path, thereby preventing the conductive path from warping or coming off.

In the method of manufacturing a circuit device according to the present invention, the conductive foil itself, which is the material of the conductive path, is made to function as a support substrate, and is used until the formation of separation grooves, the mounting of circuit elements, and the attachment of insulating resin. When the whole is supported by the conductive foil, the conductive foil is separated as each conductive path, and when an external circuit element is mounted, the insulating resin is used as a supporting substrate to function. Therefore, the circuit element, the conductive foil, and the insulating resin can be manufactured with the minimum necessary. As described in the conventional example, a support substrate is not required for originally configuring the circuit device, and the cost can be reduced. In addition, the need for a support substrate, the fact that the conductive path is embedded in the insulating resin, and the ability to adjust the thickness of the insulating resin and the conductive foil allow the formation of extremely thin circuit devices. There is also. Further, a curved structure can be formed in the step of forming the separation groove, and a structure having an anchor effect can be realized at the same time.

As is apparent from FIG. 29, the step of forming a through hole, the step of printing a conductor (in the case of a ceramic substrate), and the like can be omitted, so that the manufacturing process can be greatly reduced.
Moreover, there is an advantage that the entire process can be performed in-house. In addition, no frame mold is required at all, and the manufacturing method has a very short delivery time.

Next, since the conductive paths can be handled without being separated individually until the step of removing the conductive paths to a thickness smaller than the thickness of the conductive foil (for example, half-etching), the steps of mounting the circuit elements and covering the insulating resin are performed later. Therefore, it also has a feature of improving workability.

Since the same surface is formed of the conductive path and the insulating resin, the mounted external circuit element can be shifted without hitting the side of the conductive path on the back surface of the circuit device. In particular, it is possible to reposition the externally mounted circuit elements that are mounted in a displaced manner while being shifted in the horizontal direction. Also, if the brazing material is melted after mounting the external circuit element, the mounted external circuit element will try to return to the upper part of the conductive path by the surface tension of the melted brazing material, and the external circuit element Relocation by itself becomes possible.

Further, since the semiconductor device itself can be adopted as a mounting substrate, a semiconductor maker can supply a printed circuit board module to a set maker, and the set maker can omit mounting elements on a printed circuit board.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a circuit device of the present invention.

FIG. 2 is a diagram illustrating a method for manufacturing a circuit device according to the present invention.

FIG. 3 is a diagram illustrating a method for manufacturing a circuit device according to the present invention.

FIG. 4 is a diagram illustrating a method for manufacturing a circuit device according to the present invention.

FIG. 5 is a diagram illustrating a method for manufacturing a circuit device according to the present invention.

FIG. 6 is a diagram illustrating a method for manufacturing a circuit device according to the present invention.

FIG. 7 is a diagram illustrating a method for manufacturing a circuit device according to the present invention.

FIG. 8 is a diagram illustrating a method for manufacturing a circuit device according to the present invention.

FIG. 9 is a diagram illustrating a method for manufacturing a circuit device according to the present invention.

FIG. 10 is a diagram illustrating a method for manufacturing a circuit device according to the present invention.

FIG. 11 is a diagram illustrating a method for manufacturing a circuit device according to the present invention.

FIG. 12 is a diagram illustrating a method for manufacturing a circuit device according to the present invention.

FIG. 13 is a diagram illustrating a method for manufacturing a circuit device according to the present invention.

FIG. 14 is a diagram illustrating a method for manufacturing a circuit device according to the present invention.

FIG. 15 is a diagram illustrating a method for manufacturing a circuit device according to the present invention.

FIG. 16 is a diagram illustrating a method for manufacturing a circuit device according to the present invention.

FIG. 17 is a diagram illustrating a method for manufacturing a circuit device according to the present invention.

FIG. 18 is a diagram illustrating a method for manufacturing a circuit device according to the present invention.

FIG. 19 is a diagram illustrating a method for manufacturing a circuit device according to the present invention.

FIG. 20 is a diagram illustrating a method for manufacturing a circuit device according to the present invention.

FIG. 21 is a diagram illustrating a method for manufacturing a circuit device according to the present invention.

FIG. 22 is a diagram illustrating a circuit device according to the present invention.

FIG. 23 is a diagram illustrating a circuit device according to the present invention.

FIG. 24 is a diagram illustrating a method for mounting the circuit device of the present invention.

FIG. 25 is a diagram illustrating a method for mounting the circuit device of the present invention.

FIG. 26 is a diagram illustrating a mounting structure of a conventional circuit device.

FIG. 27 is a diagram illustrating a conventional circuit device.

FIG. 28 is a diagram illustrating a method for manufacturing a conventional circuit device.

FIG. 29 is a diagram illustrating a method for manufacturing a circuit device according to the related art and the present invention.

FIG. 30 is a diagram illustrating a conventional method up to assembling a set and a method of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 external circuit element 50 insulating resin 51 conductive path 52 circuit element 53 circuit device 54 separation groove 58 eaves 59 curved structure

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Junji Sakamoto 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (72) Inventor Shigeaki Mashimo 2-5-2 Keihanhondori, Moriguchi-shi, Osaka No. 5 Sanyo Electric Co., Ltd. (72) Katsumi Okawa 2-5-5 Keihanhondori 2-chome, Moriguchi-shi, Osaka Prefecture (72) Inventor Eiju Maehara 2 Keihanhondori, Moriguchi-shi, Osaka 5-5-5 Sanyo Electric Co., Ltd. (72) Inventor Koji Takahashi 29 Kita-cho, Isesaki-shi, Gunma F-term in Kanto Sanyo Electronics Co., Ltd. 4M109 AA01 BA03 CA21 DA04 DA10 DB02 DB15 DB16

Claims (11)

[Claims] 1. A plurality of conductive paths electrically separated by a separating groove, a circuit element fixed on the desired conductive path, and the separating groove covering the circuit element and between the conductive paths. And an external circuit element fixed to the back surface of the conductive path and exposing the back surface of the conductive path and integrally supporting the back surface of the conductive path. A circuit device characterized by being fitted with a resin. 2. A connecting means for connecting a plurality of conductive paths electrically separated by a separation groove, a desired circuit element fixed on the conductive path, and an electrode of the circuit element to another conductive path. An insulating resin that covers the circuit element and is filled in the separation groove between the conductive paths to expose and support the back surface of the conductive path integrally; and an external circuit fixed to the back surface of the conductive path. A circuit device comprising: an element; and a side surface of the conductive path being curved and fitted with the insulating resin. 3. A plurality of conductive paths electrically separated by a separating groove, a plurality of circuit elements fixed on the desired conductive path, a desired electrode of the circuit element, and the other conductive path. Connecting means for connecting; an insulating resin that covers the circuit element and is filled in the separation groove between the conductive paths to expose and support the back surface of the conductive path integrally; and affixed to the back surface of the conductive path. A circuit device comprising: an external circuit element, wherein a side surface of the conductive path is curved and fitted to the insulating resin. 4. The circuit according to claim 1, wherein the circuit element is one or both of a semiconductor bare chip, a chip circuit component, a package type semiconductor device, and a CSP. apparatus. 5. The circuit device according to claim 2, wherein said connecting means is formed of a bonding thin wire. 6. The method according to claim 1, wherein the back surface of the conductive path and the back surface of the insulating resin filled between the separation grooves are made substantially flat. Circuit device. 7. The circuit device according to claim 1, wherein the conductive path is used as an electrode, a bonding pad, a die pad, a wiring, or a connector. 8. A plurality of conductive paths which are electrically separated by separating grooves and have curved side surfaces, a desired circuit element fixed to the back surface of the conductive path, and a circuit element which covers the circuit element and is provided between the conductive paths. An external circuit element fixed to the surface of the conductive path, wherein the circuit element is made of an insulating resin that is filled in the separation groove and is made of an insulating resin that exposes the surface of the conductive path and integrally supports the conductive path. A mounting board comprising: 9. The mounting substrate according to claim 8, wherein a surface of the conductive path and a surface of the insulating resin filled between the separation grooves are made substantially flat. 10. The mounting board according to claim 8, wherein the surface of the conductive path is a bonding pad or a pad for external connection. 11. The mounting board according to claim 8, wherein the melting point of the brazing material used in the mounting board is higher than the melting point of the brazing material used on the surface of the conductive path.