JPH0855931A - Surface mounting semiconductor mounting device and substrate for surface mounting semiconductor mounting device - Google Patents

Abstract

(57) [Abstract] [Purpose] It has excellent heat dissipation and can be used with multiple terminals.
(EN) Provided is a surface mount semiconductor device which can be manufactured relatively easily at low cost and which is not structurally complicated. A plastic package in which a semiconductor element is mounted using a substrate in which the entire surface of a metal plate having a through hole is covered with an insulating layer and which is sealed with a resin, wherein one surface of the substrate on which the semiconductor element is mounted is mounted. Is provided with a die pad portion for mounting a semiconductor element, a bonding pad portion that is connected to the semiconductor element by a metal wire, and a wiring that extends from the bonding pad to the through hole portion. The surface is provided with a metal external connection terminal that is connected to the wiring, fills the inside of the through hole, and protrudes to the outside.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin-encapsulated semiconductor device (plastic package), and more particularly to a surface-mounted semiconductor device excellent in heat dissipation and capable of coping with multiple terminals (pins) and its substrate. Regarding

[0002]

2. Description of the Related Art In recent years, semiconductor devices have become more highly integrated and more functional, as typified by LSI ASICs, due to the trend toward higher performance, lighter, thinner, shorter, and smaller electronic devices (current trends). . In a highly integrated and highly functional semiconductor device, in order to process signals at a high speed, the inductance in the package has become a condition that cannot be ignored, and in order to reduce the inductance in the package, power supply and ground This has been dealt with by increasing the number of connection terminals and reducing the substantial inductance. For this reason, the higher integration and higher functionality of semiconductor devices has led to an increase in the total number of external terminals (pins), and there is an increasing demand for more terminals (pins). Multi-terminal (pin) IC, especially ASIC represented by gate array or standard cell, microcomputer, DSP (Digital Signal Proc)
In order to make semiconductor devices such as essors), PGA (Pin)
Grid Array) and QFP (Quad Flat)
A pin insertion type package such as a package) or a surface mount type package is used, and a PGA of 400 pin class and a QFP of 300 pin class have been put into practical use.

However, in recent years, the higher speed and higher performance (function) of signal processing of semiconductor devices requires more terminals. In order to deal with this, the PGA has no choice but to increase the package size, which leads to a reduction in mounting efficiency, which is not preferable. Further, in the QFP, the external terminal pitch can be narrowed to cope with a further increase in the number of terminals. However, when the external terminal pitch is narrowed, the width of the external terminal itself must be narrowed, and the external terminal strength is reduced. Becomes As a result, a problem occurs in the positional accuracy or flatness accuracy of terminal molding (gull wing formation). Further, in the QFP, as the pitch of the outer leads is further narrowed to 0.4 mm and 0.3 mm, the mounting process of these narrow pitches becomes difficult, and it is necessary to realize an advanced board mounting technology. Have an obstacle (problem).

In order to avoid the problems of the mounting efficiency and mountability of these conventional packages such as PGA and QFP, BGA (Ball Grid) is a surface mounting type package in which solder balls are replaced with external terminals of the package.
Plastic packages called Arrays have been developed. In this BGA, in order to increase the number of input / output terminals, a semiconductor element is mounted on one surface of a double-sided wiring board, and external terminal electrodes provided with spherical solder are provided on the other surface.
Conduction was established between the semiconductor element and the external terminal electrode through the through hole. By arranging the spherical solder in an array, the terminal pitch can be made wider than that of the semiconductor device using the conventional lead frame.
It was possible to cope with an increase in the number of input / output terminals without making the semiconductor device mounting process difficult. BGA generally has a structure as shown in FIG. FIG. 7B is a view seen from the back surface (substrate) side of FIG. 7A, and FIG. 7C shows the through hole 750 portion. This BGA is a base material 7 of a heat-resistant flat plate (resin plate) represented by BT resin (bismaleimide resin).
Die pad 7 on which semiconductor element 701 is mounted on one side of 02
05 and the semiconductor element 701 to the bonding wire 708
External terminals having bonding pads 710 electrically connected to each other by solder balls arranged on the other surface in a grid or zigzag pattern for electrical and physical connection with an external circuit semiconductor mounting device. Has 706,
This is a structure in which the external connection terminal 706 and the bonding pad 710 are electrically connected by the wiring 704, the through hole 750, and the wiring 704A. The conventional BGA configured using such a heat-resistant resin base material is relatively low in cost and can realize a semiconductor device compatible with multi-terminal mounting. In the case of this BGA, the semiconductor element 701
The heat generated in 1 is transmitted to an external wiring circuit via the semiconductor element 701, the wiring 704, the through hole 750, the wiring 704A, and the external terminal 706. As shown in FIG. 7 (c), a through hole is provided in the BT resin in the central portion of the die pad 705 of the substrate, and electroless plating electrolytic plating 7 is performed inside the through hole.
The heat dissipation via is improved by providing the heat conducting via 751 provided with 18 and radiating the heat directly to the mounted printed circuit board.

[0005]

A conventional plastic BGA constructed by using the above heat-resistant base material (resin plate).
Since the circuit formation for wire connection with the mounted semiconductor element and the terminal formation for mounting on the printed circuit board after forming the semiconductor device are present on both sides with the heat resistant base material interposed therebetween, Since it is necessary to form a double-sided circuit via the circuit, the circuit formation becomes complicated. The process for manufacturing a substrate for plastic BGA configured by using a heat-resistant base material is, for example, hole etching of a resin substrate, conductive plating of front and back metals, or photo-etching with tinning of through holes. It requires a process, which is a long process as a whole. In addition to this, there are many restrictions on the circuit forming process for realizing high density, and it is difficult to manufacture at low cost. Further, since the semiconductor element mounting surface side is subjected to resin molding after mounting the semiconductor element and wire connection, the through hole must be arranged and formed outside the resin molding line. Therefore, in addition to increasing the lead length from the semiconductor element to the external terminal,
There are many structural restrictions such that the size of the processed diameter of the through hole limits the size of the semiconductor device itself. Furthermore,
The heat conducting vias formed by drilling holes in a heat resistant base material (resin plate) and then copper plating have good heat dissipation to the area directly under the semiconductor element, but do not have the effect of heat diffusion throughout the package. , Heat dissipation is still a problem. The present invention is intended to solve these problems, is excellent in heat dissipation, can be used for multiple terminals, can be manufactured relatively easily at low cost, and is structurally uncomplicated and resin-sealed. A static-type surface-mount semiconductor device is provided.

[0006]

Further, in a surface mounting semiconductor mounting device of the present invention, a semiconductor element is mounted on a substrate on which a circuit is formed by using a base material in which the entire surface of a metal plate having a through hole is covered with an insulating layer. A resin-sealed semiconductor device (plastic package) mounted and sealed with a resin, wherein one surface of the substrate on which the semiconductor element is mounted has a die pad portion for mounting the semiconductor element, and a semiconductor element. A bonding pad portion connected by a metal wire and a wiring reaching the through hole portion from the bonding pad are provided, the other surface of the substrate is connected to the wiring, and the inside of the through hole is filled, In addition, it is characterized in that a metal external connection terminal protruding to the outside is provided. Then, in the above, the through-hole of the base material, the semiconductor element side,
The feature is that the diameter is smaller than the outside of the surface mounting semiconductor mounting device. . Further, in the above, the substrate is provided with a wiring in the semiconductor element mounting region, and is provided with a metal external connection terminal that is connected to the wiring, fills the inside of the through hole, and projects to the outside. The semiconductor device is characterized by being fixed via an insulating tape provided on the wiring of the substrate.
Further, in the above, the surface of the external connection terminal side is provided with a metal heat radiating terminal that fills the inside of the through hole and projects to the outside. The substrate for a semiconductor device of the present invention includes a die pad portion on which a semiconductor element is mounted, and a bonding pad connected to the semiconductor element and a metal wire on one surface of a base material in which the entire surface of a metal plate having a through hole is covered with an insulating layer. And a wiring that extends from the bonding pad to the through hole portion are formed.

[0007]

The surface-mounting semiconductor mounting device of the present invention, having the above-mentioned structure, is excellent in heat dissipation and capable of supporting multiple terminals (pins), and can be easily manufactured at low cost. It has a different structure. Further, by making the diameter of the through hole of the base material small on the semiconductor element mounting side, a large wiring area can be secured and the degree of freedom of wiring is increased. Further, by providing wiring in the region of the semiconductor element, filling the inside of the through hole from there, and connecting to the external connection terminal made of metal protruding to the outside, the through hole positioned outside the bonding pad is formed. Depending on the number of (external terminals)
The number of terminals (pins) of the semiconductor mounting device is not limited, and the limitation of the number of terminals (pins) of the semiconductor mounting device is greatly relaxed. Further, the heat dissipation property is further improved by providing the connection terminal for heat dissipation, which has the same structure as the external connection terminal made of metal and protruding to the outside. In addition, the semiconductor device substrate of the present invention can be simplified in manufacturing process and is less expensive than the conventional double-sided wiring circuit substrate made of a heat-resistant substrate with through holes (resin substrate) by the above-mentioned configuration. It is supposed to be. Further, unlike the conventional double-sided wiring circuit board, there is no need to provide through holes, and there are no restrictions on the positions of through holes, which can greatly contribute to the miniaturization of the semiconductor device itself. Since a metal plate is used as a core, it has high heat dissipation when a semiconductor element is mounted.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of a surface mount semiconductor mounting device of the present invention will be described below with reference to the drawings. FIG. 1A is a perspective view of an essential part showing an internal structure of a surface mount semiconductor mounting device according to an embodiment.
1B is a sectional view of an external connection terminal portion, FIG. 2A is a sectional view including a wiring portion, FIG. 2B is a perspective view showing a bonding pad portion, and FIG. It is a perspective sectional view of a through-hole portion. In FIG. 1, 100 is a surface mount semiconductor mounting device, 101 is a semiconductor, 102 is a substrate, 103 is a mold resin (resin), 104 is wiring, 105 is a die pad, 106 is a wiring connection portion with an external connection terminal, and 106A is external. Connection terminal, 107 is a wiring connection portion with the heat dissipation terminal, 1
Reference numeral 07A is a heat dissipation connection terminal, 108 is a bonding wire, 110 is a bonding pad, and 111 is a pilot hole. In the surface mounting semiconductor mounting device of this embodiment, the semiconductor element 10 is provided on the surface of the substrate 102 on the semiconductor element 101 side.
1. The die pad portion 105 on which the semiconductor integrated circuit 1 is mounted, the semiconductor element 101 and the bonding pad portion 110 connected by the bonding wire 108, and the wiring 10 that reaches the wiring connection portion 106 from the bonding pad 110 to the external connection terminal.
4 is provided. Then, on the other surface of the substrate 102,
A metal external connection terminal 106A integrally formed so as to project from the inside of the through hole of the substrate 102 to the outside of the semiconductor mounting device 100 is provided, and the wiring connection portion 10 with the external connection terminal is provided.
6 is connected. In addition, if necessary, the substrate 102
On the semiconductor element 101 side of the wiring connection portion 1 to the heat dissipation terminal
07 (not shown) is provided and is made of an integrated metal so as to project from the inside of the through hole of the substrate 102 to the outside of the semiconductor mounting device 100, similarly to the wiring connecting portion 106 with the external connection terminal. The heat radiating terminal 107A is connected. The semiconductor element 101 and the external circuit include a terminal portion of the semiconductor element, a bonding wire 108, a wiring 104, a wiring connection portion 106 with an external connection terminal, and an external connection terminal 106.
A and the external circuit terminal are connected in this order. The substrate 102 has a metal flat plate 120 as a core, and both surfaces thereof are covered with an insulating layer 121 as shown in FIG. 2A, and the wiring 104 and the bonding pad 110 are provided on this insulating layer. .

The bonding pad 110 is shown in FIG.
As shown in (a), the solder resist 125 of the metal foil 124 (manufactured by Tokyo Ohka Kogyo Co., Ltd., OPSR-5600) is used.
Gold is plated by electroless plating only in the portion not covered with the epoxy acryl rail, and here, the terminals (pads) of the semiconductor element 101 are wire-bonded. Except for the bonding pad 110, the wiring 104 and the metal foil 124 of the wiring connecting portion 106 to the external connection terminal are covered with the solder resist 125.

As shown in FIG. 2B, the through-hole portion of the substrate 102 is covered with an insulating layer 121 that insulates both surfaces of the substrate, and the entire surface of the through-hole portion is covered with a metal formed on the insulating layer. Wiring connection section 106 with external connection terminal made of foil 124
Is connected to the external connection terminal 106 </ b> A made of a metal that fills the through hole and projects to the outside of the surface-mounting semiconductor mounting device 100.

As described above, the surface-mounting semiconductor mounting device of this embodiment uses the substrate having the metal flat plate 120 as a core, has an excellent heat dissipation property, and is opposite to the surface on which the semiconductor element 101 is mounted. The external connection terminal 106A made of metal is provided on the entire surface of the substrate so as to integrally project from the through hole of the substrate 102 to the outside, and the structure is compatible with the increase in the number of terminals (pins). Also, the external connection terminal 10
The heat dissipation property is further improved by providing the heat dissipation terminal 107A on the surface of the 6A side.

Next, a second embodiment of the surface mount semiconductor mounting device of the present invention will be described. FIG. 3A is a perspective view of an essential part showing the internal structure of the surface mount semiconductor mounting device according to the present embodiment, and FIG.
FIG. 3 is a cross-sectional view including the semiconductor element. 301 in FIG.
Is a semiconductor element, 302 is a substrate, 303 is a mold resin (resin), 304 and 303b are wiring, 306 is a wiring connection portion with an external connection terminal, 306A is an external connection terminal, 308
Is a bonding wire, 310 is a bonding pad,
Reference numeral 311 is a bilot hole, 320 is a metal flat plate, 321 is an insulating layer, and 322 is an insulating tape. In the surface mount semiconductor mounting device of the present embodiment, the wiring 303b and the wiring connection portion 306 for the external connection terminal are also provided in a region of the substrate 302 where the semiconductor element 301 is provided, and the wiring connection portion 306 for the external connection terminal is provided. It connects to the external connection terminal 306A.
In the first embodiment, the number of terminals (pins) of the semiconductor mounted device was limited by the number of through holes (external terminals) located outside the bonding pad, but in the case of this embodiment,
Terminals (pins) can be taken from the semiconductor element 301 mounting area of the substrate 302, and terminals (pins) of the semiconductor mounting device can be obtained.
The number limit is greatly relaxed.

The surface mount semiconductor mounting device of this embodiment is shown in FIG.
As shown in (b), such a structure is made possible by providing the insulating tape 322 between the wiring 304b, the wiring connecting portion 306 to the external connection terminal, and the semiconductor element 301. As the insulating tape 322, there is a tape for adhering semiconductor elements (ITA-1030 manufactured by Sumitomo Bakelite), which has adhesive layers made of silicon-modified polyimide provided on both sides of a polyimide tape. It can be said that the present embodiment has a structure more suitable for the number of terminals (pins) than the first embodiment.

Next, a third embodiment of the surface mount semiconductor device of the present invention will be described. FIG. 4A is a sectional view of the external connection terminal portion of the surface mounting semiconductor device of this embodiment, and FIG. 4B is a sectional view of the external connection terminal portion of the first and second embodiments. In FIG. 4, reference numeral 402 is a substrate, 404 is wiring, 406 is a wiring connection portion with an external connection terminal, 406A is an external connection terminal,
Reference numeral 420 is a metal flat plate, and 421 is an insulating layer. In the case of the present embodiment, the through-hole substrate 402 provided with the connection terminal 406A
The hole diameter on the wiring 403 side (semiconductor element mounting side) should be small,
The hole diameter on the opposite side is substantially the same as that of the first and second embodiments. For this reason, the wiring routing area is increased, the degree of freedom of wiring is increased, and the number of wirings can be increased.

Next, a method of manufacturing the surface mount semiconductor mounting device of the embodiment will be briefly described. First, as shown in FIG. 5A, a large number of through holes 530 (and pilot holes 511) are formed.
Using a metal flat plate 520 made of a 42 alloy (42% Ni-iron alloy) having a shape of, a substrate 502A having a thickness of 5 to 10 μm coated with an insulating layer 521 having adhesiveness or adhesiveness was prepared. The surface of the through hole 530 portion of the base material 502A is also covered with the insulating layer 521. The shape of the through hole 530 is shown in FIG. The small hole on the semiconductor element side in FIGS. 5 (c) and (a) is in the third embodiment, and the hole diameter is the same on the outside and the semiconductor element side in FIGS. 5 (c) and (b). These are those of the first and second embodiments. Next, a metal foil (copper foil) 524 having a thickness of 18 μm was laminated on one surface of the base material 502A to produce a base material 502B having a cross section as shown in FIG. 5 (b). Next, 524 parts of the metal foil (copper foil) were subjected to plate-making etching to prepare a die pad for mounting a semiconductor element, a bonding pad, a wiring part, and a terminal part for connection with an external connection terminal, which is composed of the metal foil pattern 524A. . Next, the surface of the base material 502B other than the die pad and the bonding pad area on the side on which the semiconductor element is mounted is coated with a solder resist having a thickness of 20 μm, and then the die pad and the bonding pad area are plated with nickel on the base and electroplated with gold. Then, a substrate 502 was obtained. In addition, instead of electrolytic gold plating, electroless gold,
Alternatively, electrolytic palladium or electroless palladium plating may be performed. Next, using the substrate manufactured in this manner, the semiconductor element was mounted on the die pad portion of the substrate by die bonding, and the pad of the semiconductor element and the bonding pad of the substrate were connected by the wi bonding. After that, a semiconductor element and wiring are molded with a sealing resin (epoxy resin, manufactured by Nitto Denko Corporation, np-190), and then one side is tied from the side opposite to the side on which the semiconductor element is mounted. The solder balls are mounted on the through holes, or the solder paste is screen-printed and then melted to form spherical solder balls protruding from the inside of the through holes of the substrate to the outside of the semiconductor device. An example surface mount semiconductor mounting device was produced.

Next, a method of manufacturing the substrate used in the surface mount semiconductor mounting device of the embodiment will be described in detail with reference to the process chart of FIG. First, through-etching processes were used to form through holes having a diameter of 0.5 mm in a grid pattern at 1 mm intervals in a metal coil of 42 alloy (42% Ni-iron alloy) having a plate thickness of 0.125 mm. (A) Next, an insulating resin having adhesiveness or adhesiveness was formed on the entire surface of the metal coil in which the through holes were formed, and a substrate was manufactured. (B) This step comprises 135 parts of N, N-dimethylformamide,
P-phenylenediamine 5 parts, pyromellitic dianhydride 1
A metal coil was immersed in an electrodeposition solution in which 0 parts and 3 parts of triethylamine and 1: 1 of methanol were mixed, and a stainless steel electrode plate placed at a 50 mm interval was used as a cathode and a metal coil was used. By applying a voltage of 50 V for 10 minutes so as to serve as an anode, an insulating layer made of a polyamic acid thin film was formed on the entire surface of the metal coil. The thickness of 18 is obtained by thermocompression bonding or laminating on the insulating layer on one side.
A metal foil containing copper having a thickness of μm was bonded. At this time, the substrate has a four-layer structure including an insulating layer, a metal plate, an insulating layer, and a metal foil.

Next, wiring, die pads, and bonding pads were formed. Lamination of Asahi Kasei's dry film AQ-2536 was performed on both surfaces of the substrate.
(C) Wiring and die pad The shape of the bonding pad was exposed and developed using a photomask to form a resist pattern film, and the resist pattern film was used as a corrosion resistant film to form a metal foil pattern by etching. After this,
The resist was stripped off, and the wiring formation process was completed.
(D) Next, electroless plating was performed on the die pad and the bonding pad portion in the following manner to obtain a desired surface mounting semiconductor device mounting substrate. (E) A solder resist (OPSR-5600 epoxy acryl rail) manufactured by Tokyo Ohka Kogyo Co., Ltd. is applied to the surface of the substrate on which the wiring is formed by screen printing in a thickness of 15 μm, and after exposure and development, After curing at 150 ° C, a solder resist is formed on the surface excluding the die pad and the bonding pad, and a nickel film with a thickness of 3 μm is formed on the die pad and the bonding pad by electroless nickel plating. A palladium film having a thickness of 0.2 μm was formed by an electroless palladium-phosphorus plating solution “Mudden-Noble PD”.

[0018]

As described above, the present invention makes it possible to provide a surface mount type semiconductor mounting device which is excellent in heat dissipation and can cope with the increase in the number of terminals (pins). It is possible to provide a BGA (ball grid array) that is not a complicated structure using through holes in a BGA (ball grid array) but has a relatively simple structure and can be manufactured at low cost. . In the end, it is possible to provide a surface-mounting type semiconductor mounting device which can cope with high integration and high functionality of semiconductor elements.

[Brief description of drawings]

FIG. 1 is a diagram of a first embodiment of a surface mount semiconductor mounting device of the present invention.

FIG. 2 is a schematic view of a main part in a first embodiment of a surface mount semiconductor mounting device of the present invention.

FIG. 3 is a diagram of a second embodiment of a surface mount semiconductor mounting device of the present invention.

FIG. 4 is a diagram of a third embodiment of a surface mount semiconductor mounting device of the present invention.

FIG. 5 is a substrate diagram for a surface mount semiconductor mounting device of the present invention.

FIG. 6 is a manufacturing process diagram of a substrate for a surface-mounted semiconductor mounting device of the present invention.

FIG. 7: Conventional BGA (Ball Grid Arra)
Figure for explaining y)

[Explanation of symbols]

100 surface mount type semiconductor device 101, 301 semiconductor element 102, 302, 402 substrate 103 mold resin (resin) 104, 304, 304b, 404 wiring 105 die pad 106, 306, 406 wiring connecting portion 106A, 306A with external connection terminal 406A External connection terminal 107 Wiring connection portion with heat dissipation terminal 107A Heat dissipation connection terminal 108 Bonding wire 110 Bonding pad 111 Pilot hole 120, 320, 420 Metal flat plate 121, 321, 421 Insulation layer 124 Metal foil 125 Solder resist 322 Insulation tape 502A, 502B Base material 511 Pilot hole 520 Metal flat plate 521 Insulating layer 524 Metal foil (copper foil) 530 Through hole 701 Semiconductor element 702 Base material 703 Mold resin ( Resin) 704, 704A Wiring 705 Die pad 706A External connection terminal 708 Bonding wire 710 Bonding pad 718 Plated part 724 Metal foil 750 Through hole 751 Thermal conduction via

Claims (6)

[Claims] 1. A resin-encapsulated semiconductor device in which a semiconductor element is mounted on a substrate on which a circuit is formed by using a base material in which an entire surface of a metal plate having a through hole is covered with an insulating layer and which is sealed with a resin. , On one surface of the substrate on which the semiconductor element is mounted,
A die pad portion for mounting a semiconductor element, a bonding pad portion connected to the semiconductor element by a metal wire, and a wiring reaching from the bonding pad to the through hole portion are provided, and the other surface of the substrate is provided. A surface-mounted semiconductor mounting device comprising: a metal external connection terminal that is connected to the wiring, fills the inside of the through hole, and projects to the outside. 2. The surface mounting semiconductor mounting device according to claim 1, wherein the through hole of the base material has a smaller diameter on the semiconductor element side than on the outside of the surface mounting semiconductor mounting device. 3. The external connection terminal according to claim 1, wherein the substrate is provided with a wiring in a semiconductor element mounting region and is connected to the wiring, fills the inside of the through hole, and projects to the outside. A surface mount semiconductor mounting device characterized by being provided with. 4. The surface mount semiconductor mounting device according to claim 3, wherein the semiconductor element is fixed via an insulating tape provided on the wiring of the substrate. 5. The surface mount semiconductor mounting device according to claim 1, wherein the surface of the external connection terminal side is provided with a metal radiating terminal that fills the inside of the through hole and projects to the outside. apparatus. 6. A die pad portion on which a semiconductor element is mounted, a bonding pad portion connected to the semiconductor element by a metal wire, and a bonding pad portion on one side of a base material in which the entire surface of a metal plate having a through hole is covered with an insulating layer. A substrate for a surface mounting semiconductor mounting device, characterized in that a wiring reaching from the bonding pad to the through hole portion is formed.