JPH11251478A - Semiconductor device and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor device for increasing the number of connection terminals and for reducing package size. SOLUTION: A wiring substrate 50 is jointed to the counter metal plate side of a package body 30 with a metal plate 10 and a printed wiring board 20 by a relay terminal 40 a, and an input/output terminal 54 that is provided at the counter package body side of the wiring board 50 is connected electrically to an electrode part 71 of a semiconductor element 70 via a bonding wire 80, a wiring layer 22, and a relay terminal 40. As a result, the input/output terminal 54 can be arranged also directly below a cavity part 60 of the package body 30. By arranging the input/output terminal 54 on the entire surface of the lower surface of the package body 30, the number of terminals to be connected to a printed circuit board(PCB) 200 can be increased, thus mounting highly dense semiconductor elements and increasing speed and further increasing the latitude in designing a semiconductor device and reducing a package size.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a semiconductor device and a method of manufacturing the same, and more particularly, to a semiconductor device having a semiconductor element mounted in a cavity-down type semiconductor package and a method of manufacturing the same.

[0002]

2. Description of the Related Art In a semiconductor device, an IC chip or an LS
2. Description of the Related Art A semiconductor element such as an I-chip is mounted on a semiconductor element mounting portion provided in a semiconductor package and put to practical use. The resin mold package has a lower manufacturing cost than a ceramic semiconductor package.Especially, a semiconductor element is mounted on a printed wiring board without using a lead frame, and solder balls attached to the electrodes of the printed wiring board are used. PBGA (Plast
ic Ball Grid Array). PBGA is
Compared to a package using a lead frame such as a QFP (Quad Flat Package), the number of pins can be increased because the leads are provided in a planar manner. Since the lead pitch is large and the accuracy of the mounter or the like may be low, the manufacturing yield is improved.
It has advantages such as relatively low manufacturing cost.

In a conventional PBGA, a semiconductor element is mounted on an upper portion of a printed wiring board, and a bonding wire, wiring of the printed wiring board, through holes provided around the printed wiring board, an electrode portion below the printed wiring board, and the like are provided. The electrode portion of the semiconductor element is electrically connected to a solder ball or the like via a via, and is sealed with a mold resin after the semiconductor element is mounted. However, the above-mentioned PBGA has a disadvantage that heat dissipation and moisture resistance are insufficient because the whole surrounding the semiconductor element is made of an organic material.

Therefore, in order to improve heat dissipation and moisture resistance, which are the drawbacks of the PBGA, a cavity-down BGA (C
avity Down-Ball Grid Array) has been proposed. Cavity down BGA, the printed wiring board is bonded to the metal plate such as copper alloy so that the cavity (Cavity) is downward (Down), after mounting the semiconductor element in the cavity,
The printed circuit board is connected to the motherboard by solder balls or the like via the wiring and the electrode section. Resin sealing of the cavity after mounting the semiconductor element is performed by a molding method or a potting method. Since the cavity-down BGA is provided with a metal plate for heat dissipation on the upper part, heat dissipation and moisture resistance can be improved.

[0005]

However, in the above-mentioned cavity-down BGA, the solder balls and the like as connection terminals for connection to the motherboard and the opening of the cavity for mounting the semiconductor element are on the same surface of the printed wiring board. Side, the connection terminals could not be arranged on the entire lower surface of the package, and the arrangement of the connection terminals was limited. Therefore, since the number of connection terminals cannot be increased, there is a problem that it is difficult to mount a higher-density semiconductor element to increase the speed of the semiconductor device.

Further, since the pitch of the electrode portions of the motherboard is standardized, the interval between the connection terminals cannot be widened, and there is a problem that the degree of freedom in designing a semiconductor device is relatively narrow. Furthermore, since the interval between the connection terminals cannot be reduced, there is a problem that it is difficult to reduce the package size.

[0007] The present invention has been made to solve such a problem, and has as its object to provide a semiconductor device capable of increasing the number of connection terminals. Another object of the present invention is to provide a semiconductor device which has a large degree of freedom in design and can reduce a package size.

[0008]

According to a first aspect of the present invention, there is provided a semiconductor device, wherein a wiring board is provided on a side of a package body having a printed wiring board and a heat radiator, on a side opposite to the heat radiator. An input / output terminal electrically connected to the wiring of the wiring board is provided on the side opposite to the package body. For this reason, it is possible to arrange the input / output terminals directly below the cavity, and by arranging the input / output terminals on the entire lower surface of the package, the number of terminals connected to the motherboard can be increased. Therefore, it is possible to mount a higher density semiconductor element to increase the speed of the semiconductor device.

Further, the design of the semiconductor device can be easily changed while adjusting the pitch of the input / output terminals to the pitch standard of the electrode portion of the motherboard, so that the degree of freedom in the design of the semiconductor device is increased and the package size is increased. Can be reduced. According to the semiconductor device of the present invention, a relay terminal is provided between the package body and the wiring board, and the package body and the wiring board are joined by the relay terminal, so that the wiring of the printed wiring board and the input / output terminal are provided. And are electrically connected. Therefore, by using a conductive adhesive or a solder ball as a relay terminal, it is possible to simultaneously connect the package body and the wiring board and electrically connect the wiring of the printed wiring board and the input / output terminals. Becomes Therefore, the input / output terminals can be arranged on the entire lower surface of the package with a simple configuration.

According to the method of manufacturing a semiconductor device according to the third aspect of the present invention, the package body is manufactured by bonding the printed wiring board to the radiator so that the cavity faces downward, and the semiconductor element is mounted in the cavity. To electrically connect the semiconductor element and the wiring of the printed wiring board, and to connect the wiring board to the anti-radiator side of the package body to electrically connect the wiring of the printed wiring board and the wiring of the wiring board; An input / output terminal electrically connected to the wiring of the printed wiring board is provided on the side opposite to the package body of the substrate. Therefore, the input / output terminals can be easily arranged on the entire lower surface of the package.

As the printed wiring board, a heat-resistant resin film or a thin laminated board can be used as a base material. The material of the film is preferably, for example, a resin such as polyimide, polyester, polyamide, or polyether ethene ketone, and the resin of the laminate is preferably epoxy, polyimide, bismaleimide triazine (BT), or the like. Wiring is copper (Cu)
Can be formed by photolithography, etching, oxidation treatment, or the like of a thin layer such as The laminate can be laminated with epoxy or the like using glass or the like as a reinforcing plate. The electrical connection between the wirings of the laminated board can be made by drilling a conductive via hole or a through-hole plated with Cu or the like or by irradiating a laser to remove unnecessary matter and then plating. Nickel (N
i), the electrode portion can be formed by plating with gold (Au) or the like.

As the radiator, it is preferable to use a copper material or a copper alloy material from the viewpoint of heat dissipation and thermal conductivity. The heat dissipator may have one metal plate or two metal plates. Further, a concave portion may be formed in the above-mentioned metal plate, or a concave portion which is depressed upward may be formed in the above-mentioned metal plate. In order to adhere the heat radiator to the printed wiring board, it is preferable to use an adhesive sheet or an adhesive.

In order to mount the semiconductor element in the cavity, it is preferable to bond the semiconductor element to the heat radiator with an adhesive having excellent thermal conductivity such as silver-containing epoxy. The electrical connection between the semiconductor element and the wiring layer of the printed wiring board is preferably wire bonding, but is not limited to wire bonding, and may be a flip chip or TAB (Tape Automated Bonded).
g).

As the wiring substrate, wiring is formed on the front or back surface of the resin substrate, conductive via holes or through holes plated with Cu or the like are formed, and N
A known printed wiring board having electrode portions formed on the front and back surfaces of a resin substrate by plating with i, Au, or the like can be used. It is preferable to use a solder ball, a conductive adhesive, or the like as the input / output terminal.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. One embodiment in which the present invention is applied to a wire bonding type cavity down BGA,
This will be described with reference to FIGS. As shown in FIG. 1, a cavity-down BGA 100 according to the present embodiment includes a package body 30, a semiconductor element 70 mounted on a cavity 60 of the package body 30, and a wiring board provided on the cavity opening side of the package body 30. 50, and a relay terminal 40 provided between the package body 30 and the wiring board 50 to join the package body 30 to the wiring board 50.

The package body 30 has a metal plate 10 as a heat radiator and a printed wiring board 20, and the printed wiring board 20 is bonded to the metal plate 10 so that the cavity 60 faces downward. The metal plate 10 includes a flat plate 11 made of a copper material or a copper alloy material, and a rectangular plate 12 made of a copper material or a copper alloy material, and having a substantially central portion cut out. Here, the thickness of the square-shaped plate 12 is set so that the semiconductor element 70 mounted in the cavity 60 can be easily bonded to the printed wiring board 20.
It is preferably about the same as the thickness of 0.

The printed wiring board 20 includes insulating layers 21 and 23 such as BT and a wiring layer 2 such as Cu as wiring.
2 is made of a thin laminated board laminated with epoxy resin, etc.
It has a conductive via hole (not shown) or a through hole plated with Cu or the like. An electrode portion (not shown) is formed on the lower surface 24 of the insulating layer 23 by plating the exposed portion of the wiring with Ni, Au, or the like. Metal plate 10
The printed wiring board 20 is bonded to the printed wiring board 20 with an adhesive sheet or an adhesive (not shown). As a material of the adhesive sheet, for example, epoxy or acrylic resin is used, and as a material of the adhesive, for example, epoxy or polyimide resin is used.

A semiconductor element 70 is mounted in the cavity part 60, and an electrode part 71 of the semiconductor element 70 is bonded to a predetermined bonding point of the wiring layer 22 of the printed wiring board 20 by a bonding wire 80. The semiconductor element 70 is bonded to the flat plate 11 of the metal plate 10 with an adhesive having excellent thermal conductivity such as a silver-containing epoxy (not shown). The cavity portion 60 is filled with an insulating encapsulant 90 made of a resin such as epoxy, and encloses at least a part of the semiconductor element 70 and the bonding wire 80.

The wiring substrate 50 is provided on the cavity opening side of the package body 30, that is, on the side opposite to the metal plate, and has an upper surface 52 of an insulating layer 51 made of, for example, glass-epoxy.
Alternatively, a wiring (not shown) such as Cu is formed on the lower surface 53,
A conductive via hole (not shown) or a through-hole plated with Cu or the like is formed in the insulating layer 51, and the exposed portions of the wiring on the upper and lower surfaces 52 and 53 of the insulating layer 51 are plated with Ni, Au, or the like to form an electrode portion (not shown). Are formed. The wiring substrate 50 has input / output terminals 54 such as solder balls and conductive adhesive on the side opposite to the package body.

A relay terminal 40 such as a conductive adhesive or a solder ball is provided between the package body 30 and the wiring board 50. The relay terminal 40 joins the printed wiring board 20 and the wiring board 50, and electrically connects the wiring layer 22 of the printed wiring board 20 and the wiring of the wiring board 50. Therefore, the relay terminal 40 is connected to the semiconductor element 7 via the bonding wire 80 and the wiring layer 22.
0 is electrically connected to the electrode portion 71.

With the above configuration, the input / output terminals 54 of the wiring board 50 are electrically connected to the electrode portions 71 of the semiconductor element 70 via the relay terminals 40, and the cavity-down BGA 100 is connected to the motherboard by the input / output terminals 54. It can be connected to a PCB (Print Circuit Board) 200. Next, the cavity down BGA 1 shown in FIG.
00 will be described.

(1) First, as shown in FIG.
Insulating layers 21 and 23 such as Cu and a wiring layer 22 such as Cu are laminated with an epoxy resin or the like, and a conductive via hole or Cu
The printed wiring board 20 is manufactured by forming through-holes plated with a metal or the like, and plating the exposed portions of the wiring on the lower surface 24 of the insulating layer 23 with Ni, Au or the like to form electrode portions. Next, a flat plate 11 made of a copper material or a copper alloy material,
Similarly, a metal plate 10 made of a copper material or a copper alloy material and having a square-shaped plate 12 having a substantially central portion hollowed out is prepared. Then, using an adhesive sheet such as an epoxy or acrylic resin or an adhesive such as an epoxy or polyimide resin, the metal plate 1 is placed so that the cavity 60 faces downward.
0 to the package body 30
Is prepared.

(2) As shown in FIG. 3, the semiconductor element 70 is bonded to the flat plate 11 of the metal plate 10 with an adhesive having excellent thermal conductivity such as silver-containing epoxy, for example. The semiconductor element 70 is mounted on the semiconductor device 60, and a predetermined bonding point of the wiring layer 22 of the printed wiring board 20 and an electrode portion 71 of the semiconductor element 70 are bonded by a bonding wire 80. Then, the cavity 60 is filled with an insulating encapsulant 90 made of a resin such as epoxy, and the semiconductor element 70 and the bonding wire 80 are filled.
At least a part of is enclosed.

(3) As shown in FIG. 4, a relay terminal 40 such as a conductive adhesive or a solder ball is attached to the electrode portion on the lower surface 24 of the insulating layer 23. At this time, the relay terminal 40
Is electrically connected to the electrode portion 71 of the semiconductor element 70 via the bonding wire 80 and the wiring layer 22. (4) As shown in FIG. 5, for example, a wiring such as Cu is formed on the upper surface 52 or the lower surface 53 of the insulating layer 51 such as glass-epoxy, and a conductive via hole or a through hole plated with Cu or the like is formed in the insulating layer 51. Formed on the upper and lower surfaces 5 of the insulating layer 51.
Electrodes are formed by plating the exposed portions of the wirings 2 and 53 with Ni, Au, or the like, to produce a printed wiring board. At this time, the pitch of the electrode portions on the upper surface 52 of the insulating layer 51 is adjusted to the relay terminal 40. Then, the insulating layer 51
The printed wiring board is disposed on the cavity opening side of the package body 30, that is, on the side opposite to the metal plate, by attaching the electrode portion of the upper surface 52 to the relay terminal 40.

(5) As shown in FIG. 6, an input / output terminal 54 such as a solder ball or a conductive adhesive is attached to the electrode portion on the lower surface 53 of the insulating layer 51 to complete the wiring board 50.
The cavity down BGA 100 is manufactured. here,
The space between the package body 30 and the wiring board 50 may be filled with a resin such as epoxy. Through the above steps (3) to (5), the wiring board 50 having the input / output terminals 54 on the side opposite to the package main body is joined to the opposite metal plate side of the package main body 30 by the relay terminals 40. Is electrically connected to the electrode portion 71 of the semiconductor element 70 via the bonding wire 80, the wiring layer 22, and the relay terminal 40. At this time, the physical joining and the electrical connection can be performed simultaneously, so that the input / output terminals 54 can be simply and easily arranged on the entire lower surface of the package body 30.

Next, a description will be given of a comparative example in which a relay terminal and a wiring board are not provided, and a connection terminal 55 such as a solder ball is provided on the cavity opening side of the package body 30 as shown in FIG. The same reference numerals are given to substantially the same parts as those in the embodiment shown in FIG. In the comparative example shown in FIG.
Since the connection terminal 55 connected to the PCB 200 and the opening of the cavity portion 60 of the package body 30 are on the same surface side of the printed wiring board 20, the connection terminal 55 can be arranged on the entire lower surface of the package body 30. However, the arrangement of the connection terminals 55 is restricted. Therefore, since the number of connection terminals cannot be increased, it is difficult to mount a higher-density semiconductor element and increase the speed of the semiconductor device. In addition, since the pitch of the electrode portion of the PCB 200 is standardized, the interval between the connection terminals cannot be widened, and the degree of freedom in designing the semiconductor device is relatively narrow. Furthermore, since the interval between the connection terminals cannot be narrowed,
It is difficult to reduce the package size.

On the other hand, in this embodiment, the wiring board 50 is provided on the side of the package body 30 opposite to the metal plate by the relay terminal 40.
And the input / output terminals 54 provided on the opposite side of the package body of the wiring board 50 are electrically connected to the electrode portions 71 of the semiconductor element 70 via the bonding wires 80, the wiring layers 22, and the relay terminals 40. For this reason, the input / output terminals 5 are also provided immediately below the cavity 60 of the package body 30.
4 can be arranged, and by arranging the input / output terminals 54 on the entire lower surface of the package body 30,
The number of terminals connected to the CB 200 can be increased.
Therefore, it is possible to mount a higher density semiconductor element to increase the speed of the semiconductor device.

Further, in this embodiment, the PCB 200
It is possible to easily change the design of the semiconductor device while adjusting the pitch of the input / output terminals 54 to the pitch standard of the electrode portion, thereby increasing the degree of freedom in designing the semiconductor device and reducing the package size. It becomes possible. In the present embodiment, the two metal plates 10 having the flat plate 11 and the square-shaped plate 12 are used as the heat radiator. However, in the present invention, the material, shape and number of the heat radiator are not limited. Therefore, in the present invention, a heat radiator having a concave portion may be used, or a heat radiator having a concave portion formed upward may be used.

In this embodiment, a laminated board in which insulating layers 21 and 23 of BT or the like and a wiring layer 22 of Cu or the like are laminated with an epoxy resin or the like is used for the printed wiring board 20. The printed wiring board is not limited to its material and configuration, and a resin film or the like may be used. Further, in the present embodiment, a printed wiring board having an insulating layer 51 of glass-epoxy or the like is used for the wiring board 50. However, in the present invention, the wiring board is not limited to its material and configuration, and may be made of ceramics or the like. May be used.

In the present invention, the bonding between the semiconductor element and the printed wiring board is not limited to wire bonding, but may be performed by flip chip or TAB. When bonding a semiconductor element and a printed wiring board by flip chip or TAB, the printed wiring board may be bonded to the entire surface of the metal plate.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an embodiment in which the present invention is applied to a wire bonding type cavity down BGA.

FIG. 2 shows a cavity down BG according to an embodiment of the present invention.
It is a schematic cross section for explaining the manufacturing method of A.

FIG. 3 shows a cavity down BG according to an embodiment of the present invention.
It is a schematic cross section for explaining the manufacturing method of A.

FIG. 4 shows a cavity down BG according to an embodiment of the present invention.
It is a schematic cross section for explaining the manufacturing method of A.

FIG. 5 shows a cavity down BG according to an embodiment of the present invention.
It is a schematic cross section for explaining the manufacturing method of A.

FIG. 6 shows a cavity down BG according to an embodiment of the present invention.
It is a schematic cross section for explaining the manufacturing method of A.

FIG. 7 is a schematic sectional view showing a cavity-down BGA of a comparative example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Metal plate (heat radiator) 20 Printed wiring board 21 Insulating layer 22 Wiring layer (wiring) 23 Insulating layer 30 Package body 40 Relay terminal 50 Wiring board 54 I / O terminal 60 Cavity part 70 Semiconductor element 80 Bonding wire 90 Insulation sealing material 100 Cavity down BGA 200 PCB (motherboard)

Claims (3)

[Claims] 1. A printed circuit board having a semiconductor element, a wiring electrically connected to the semiconductor element, a radiator for radiating heat generated in the semiconductor element to the outside, and the semiconductor element mounted downward. A cavity-down type package main body having a cavity portion, a wiring board provided on the anti-radiator side of the package main body, and having an input / output terminal on the anti-package main body side electrically connected to the wiring of the printed wiring board; A semiconductor device comprising: 2. A relay provided between the package body and the wiring board to join the package body and the wiring board and electrically connect the wiring of the printed wiring board to the input / output terminals. The semiconductor device according to claim 1, further comprising a terminal. 3. A package body in which a printed wiring board having wiring electrically connected to a semiconductor element is bonded to a radiator for radiating heat generated in the semiconductor element to the outside so that a cavity portion faces downward. Manufacturing a semiconductor element in the cavity portion, and electrically connecting the semiconductor element and the wiring of the printed wiring board; and bonding a wiring board to an anti-radiator side of the package body,
A step of electrically connecting the wiring of the printed wiring board and the wiring of the wiring board; and a step of providing input / output terminals electrically connected to the wiring of the printed wiring board on a side of the wiring board opposite to the package body. A method for manufacturing a semiconductor device, comprising: