JPH0832007A - Semiconductor device and semiconductor device assembly - Google Patents

Abstract

(57) [Summary] [Purpose] To improve the heat dissipation of IC packages. [Structure] The heat dissipation lead pins (12a to 12d) are die pads (11) on which a semiconductor chip (20) is mounted.
The heat generated in the chip (20) is efficiently transferred to the outer lead portions of the heat radiation lead pins (12a to 12d) because it is integrated with the chip. Therefore, the heat dissipation lead pin (12a
It is possible to prevent the temperature of the semiconductor chip from rising by connecting (~ 12d) to the heat sink (61, 62). When the heat dissipation lead pins (12a to 12d) and the electrode lead pins (13a to 13b) are bent in opposite directions, the wiring board (7) on one side performs signal input / output and power supply while the other side is performed. Heat sink (61,6
Heat can be dissipated in 2). In addition, the heat sink (61, 6
When 2) is formed of a conductive material, the ground of the semiconductor chip (20) can be strengthened through the heat radiation lead pins (12a to 12d).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device and a semiconductor device assembly, and more particularly, it is applied to an IC package by a Small Outline Package (SOP) mounting method using a lead frame.

[0002]

2. Description of the Related Art There are various methods for plastic packaging of IC chips. For example, the SOP is the "Microelectronics Packaging Handbook" by Nikkei BP (P.
419-428). Higher performance and higher density of electronic devices lead to higher integration of ICs, so it is important to prevent temperature rise due to heat generation by heat dissipation. In particular, the SOP is a package with high thermal resistance, so unless some measures are taken, an IC with high heat generation density
It cannot be used for chip packaging.

[0003] In the plastic package such as SOP, for example high frequency IC chip exceeds 1GH _Z is or partially attached to the power supply of the device was not output for ground reinforcement of power supply, the noise is high There was a problem that became.

The present invention has been made in view of the above-mentioned conventional technique, and an object thereof is to improve heat dissipation in a semiconductor device, and also to strengthen the ground and reduce noise. .

[0005]

SUMMARY OF THE INVENTION According to the present invention, a semiconductor chip is mounted on a die pad of a lead frame, and outer lead portions of a plurality of lead pins are projected outward to be molded, whereby a rectangular resin member is integrated. In the integrated semiconductor device, the lead pins include a plurality of electrode lead pins whose inner lead portions are connected to the semiconductor chip via bonding wires, and a plurality of heat dissipation leads whose inner lead portions are integrally formed with the die pad. And a plurality of heat-radiating lead pins project outward from a side surface orthogonal to a side surface of the rectangular resin member from which the plurality of electrode lead pins project.

The outer lead portions of the plurality of heat radiation lead pins and the plurality of electrode lead pins may be bent in mutually opposite directions, and the tips of the plurality of heat radiation lead pins may be connected to a heat sink. The inner lead portion of the lead pin may be connected to the ground electrode pad of the semiconductor chip, and the heat sink may be made of a conductive material.

Further, the semiconductor device assembly of the present invention has the above-mentioned semiconductor device and a wiring pattern formed on the surface thereof.
A wiring board in which the tips of a plurality of electrode lead pins bent in the outer lead portion are connected to the wiring pattern, and the tips of a plurality of heat dissipation lead pins in which the outer lead portion is bent in the opposite direction to the electrode lead pins. And a fixing member for fixing the heat sink to the wiring board. Here, even if the inner lead portion of the heat dissipation lead pin is connected to the ground electrode pad of the semiconductor chip, the heat sink and the fixing member are made of a conductive material, and the fixing member is connected to the ground wiring pattern of the wiring board. Good.

[0008]

According to the structure of the present invention, since the heat radiation lead pin is integrated with the die pad on which the semiconductor chip is mounted, the heat generated in the chip is efficiently transmitted to the outer lead portion of the heat radiation lead pin. Therefore, if the heat dissipation lead pins are connected to the heat sink, it is possible to prevent the temperature of the semiconductor chip from rising. In addition, when the heat radiation lead pin and the electrode lead pin are bent in opposite directions, heat can be radiated by the heat sink on the other side while inputting and outputting signals and supplying power on the wiring substrate on one side. further,
When the heat sink is made of a conductive material, the ground of the semiconductor chip can be strengthened via the heat radiation lead pins.

According to the semiconductor device assembly of the present invention, the above semiconductor device is connected to the wiring board by the lead pins for electrodes, and the heat sink is connected to the lead pins for heat dissipation. Since the heat sink is fixed to the wiring board by the fixing member, the structure for heat dissipation can be stably held. Further, if the heat sink and the fixing member are made of a conductive material and are connected to the ground pattern, the heat dissipation structure, the ground reinforcement and the electromagnetic shield structure can be achieved at the same time.

[0010]

EXAMPLES Examples will be described below with reference to the accompanying drawings.
The same elements will be denoted by the same reference symbols, without redundant description.

FIG. 1 is a plan view showing a mutual relationship between a lead frame used in a semiconductor device (IC package) according to an embodiment, a semiconductor chip and a molding resin. As shown in FIG. 1, two heat radiation lead pins 12a to 12d extend vertically from the rectangular die pad 11.
The tips are supported by the upper and lower frame bodies 10a and 10b. Four electrode lead pins 13a to 13h extend to the left and right of the die pad 11 to dissipate heat.
Are arranged in a direction orthogonal to ~ 12d, and the tie bars 14a,
Four frames 14b are supported by the frame main bodies 10a and 10b. Each element of the lead frame is manufactured by stamping a single metal plate.

I in which circuit elements are integrated on a semiconductor chip
The C chip 20 is die-bonded to the die pad 11, and the electrode pads of the die pad 11 and the inner lead portions of the electrode lead pins 13a to 13h are electrically connected by the bonding wires 5a to 5h. Then, all of the die pad 11 and the IC chip 20, the heat dissipation lead pins 12a to 12d, and the electrode lead pin 13a.
The inner lead part of ~ 13h is a rectangular mold resin 3
It is integrated by 0.

FIG. 2 is a plan view after the unnecessary portions (frame bodies 10a, 10b and tie bars 14a, 14b) of the lead frame are cut and removed after resin molding. The inside of the mold resin 30 is shown by a dotted line. As shown in the figure, the mold resin 30 has a rectangular shape, and electrode lead pins 13a to
Four 13h protrude in the left and right directions. Also,
Heat dissipation lead pins 12a to 12d from both lateral sides
Two are projected in the vertical direction. Since the heat dissipation lead pins 12a to 12d are integrally formed with the die pad 11 and the IC chip 20 is die-bonded to the die pad 11, it is understood that the heat of the IC chip 20 is satisfactorily transferred to the heat dissipation lead pins 12a to 12d. Further, since the inner lead portions of the electrode lead pins 13a to 13h are wire-bonded to the IC chip 20, it can be seen that power supply and signal input / output can be suitably performed.

Therefore, as shown in FIG. 3, heat radiation lead pins 12a to 12d and electrode lead pins 13a to 13h.
Are bent in opposite directions at the base of the outer lead portion. The figure is a plan view, a front view, and a right side view.
As shown in the figure, the heat dissipation lead pins 12a to 12d are bent upward at the base of the outer lead, and their tips are bent in the opposite direction and protrude outward. Lead pin for electrode 1
3a to 13h are bent downward at the base of the outer lead, and their tips are bent in the opposite direction and protrude outward. The tips of the heat radiation lead pins 12a to 12d and the electrode lead pins 13a to 13h are all parallel to the surface direction of the lead frame on the same plane.

FIG. 4 shows the structure of a semiconductor device assembly using the IC package of FIG. A heat radiating plate 61 is fixed to the tips of the four heat radiating lead pins 12a to 12d with solder or the like. The upper surface of the heat dissipation plate 61 has three heat dissipation fins 62a to 62c, which constitute a heat sink. Eight electrode lead pins 13a to 13h
A wiring board 7 having a wiring pattern (not shown) is fixed to the tip of the substrate by soldering or the like. A resin 8 is sealed and solidified between the wiring board 7 and the heat dissipation plate 61, as will be described with a chain double-dashed line in the drawing. It is desirable that the encapsulating resin 8 has a good thermal conductivity, so that the radiating fins 62 are tightly fixed to the wiring board 7.

In FIG. 5, the heat dissipation plate 61 has four support rods 9a to 9a.
It differs from FIG. 4 in that it is fixed to the wiring board 7 at 9d. In the figure, the support rods 9a to 9d are "bolts".
However, various forms such as pins and rods are possible as long as they are members for fixing. In this example, there is an effect that the heat dissipation plate 61 can be firmly fixed by the support rods 9a to 9d, but the resin 8 may be injected and solidified as in FIG. In the figure, the resin 8 is shown by a chain double-dashed line.

FIG. 6 shows an IC package according to another embodiment of the present invention. The difference from FIG. 3 is that the ground electrode pad of the IC chip 20 and the die pad 11 are electrically connected by the two bonding wires 4i and 4j. In this case, the heat dissipation lead pins 12a to 12d serve as a ground terminal. Therefore, if the heat dissipation plate 61 and the supporting rods 9a to 9d are formed of a conductive metal or the like and any one of the supporting rods 9a to 9d is connected to a wiring pattern (metallized pattern) (not shown) on the wiring board 7, Structures for ground enhancement and electromagnetic shielding are achieved along with structures for heat dissipation.

The above embodiment can be embodied in various modes. For example, the IC chip 20 may be a Si chip or a GaAs chip, and the type of electronic circuit mounted does not matter. Lead frame is Cu (copper)
Alternatively, various materials may be used as long as they are made of a material having good heat conduction such as 4.2 alloy. Further, Au (gold), Al (aluminum), or the like can be used as the bonding wire. For the heat sink including the heat radiating plate 61 and the heat radiating fins 62, Ni /
A brass product plated with Cr / Au can be used.

When mounting the IC package and the heat sink on the wiring board 7, for example, the following may be carried out. That is, first, the pad portion (13a-
Parts other than 13h) are coated with an insulating resin such as polyimide. Then, using solder etc., IC
The package is mounted on the wiring board 7, and then the heat dissipation plate 61 is mounted by soldering or the like. Then, a resin having a high thermal conductivity such as an epoxy resin containing Ag (silver) filler is introduced and cured. As a result, it is possible to realize a structure that is good in heat dissipation, excellent in electromagnetic shielding, and mechanically strong.

[0020]

As described in detail above, according to the present invention,
In addition to the electrode lead pins, the die pad is provided with integrated heat radiation lead pins, and these are projected in directions orthogonal to each other. Therefore, it is possible to attach a heat sink to the other surface while being connected to the wiring substrate on one surface. Since the IC chip can be grounded via this heat sink, a structure having excellent heat dissipation and a strengthened ground can be realized. Further, according to the present invention, there is an effect that the degree of freedom in wiring design can be increased.

[Brief description of drawings]

FIG. 1 is a diagram showing a lead frame according to an embodiment.

FIG. 2 is a plan view of an IC package according to an embodiment.

FIG. 3 is a plan view, a front view, and a side view of an IC package according to an embodiment.

FIG. 4 is a plan view, a front view and a side view of an assembly using the IC package of FIG.

5 is a plan view, a front view and a side view of an assembly using the IC package of FIG.

FIG. 6 is a plan view of another IC package.

[Explanation of symbols]

10a, 10b ... Frame body, 11 ... Die pad, 1
2a to 12h ... Heat dissipation lead pins, 13a to 13d ... Electrode lead pins, 20 ... IC chip, 30 ... Mold resin, 5a-5j ... Bonding wires, 61 ... Heat sink,
62a-62c ... Radiating fins, 7 ... Wiring board, 8 ... Encapsulating resin, 9a-9d ... Support rods.

Claims (5)

[Claims] 1. A semiconductor device integrated with a rectangular resin member by mounting a semiconductor chip on a die pad of a lead frame and molding the outer lead portions of a plurality of lead pins outwardly by projection molding. The plurality of lead pins includes a plurality of electrode lead pins whose inner lead portions are connected to the semiconductor chip via bonding wires, and a plurality of heat dissipation lead pins whose inner lead portions are integrally molded with the die pad, The semiconductor device, wherein the plurality of heat dissipation lead pins protrude outward from a side surface orthogonal to a side surface of the rectangular resin member from which the plurality of electrode lead pins protrude. 2. The plurality of heat radiation lead pins and the plurality of electrode lead pins have outer lead portions bent in mutually opposite directions, and tips of the plurality of heat radiation lead pins are connected to a heat sink. The semiconductor device described. 3. The semiconductor device according to claim 2, wherein an inner lead portion of the heat dissipation lead pin is connected to a ground electrode pad of the semiconductor chip, and the heat sink is made of a conductive material. 4. The semiconductor device according to claim 1, a wiring board having a wiring pattern formed on a surface thereof, wherein the tip ends of the plurality of electrode lead pins bent at the outer lead portion are connected to the wiring pattern. A lead portion is provided with a heat sink connected to the tips of the plurality of heat dissipation lead pins bent in a direction opposite to the electrode lead pins; and a fixing member for fixing the heat sink to the wiring board. Semiconductor device assembly. 5. The inner lead portion of the heat dissipation lead pin is connected to a ground electrode pad of the semiconductor chip, the heat sink and the fixing member are made of a conductive material, and the fixing member is for the ground of the wiring board. The semiconductor device assembly according to claim 4, wherein the semiconductor device assembly is connected to a wiring pattern.