JP2003282805A - Semiconductor device using semiconductor chip - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor device that can be reduced in size and weight or is capable of using a large semiconductor chip, which is composed of one metal plate lead terminal 2 provided with a square island 3, the square semiconductor chip 4 bonded to the island 3 with a die bonding agent 7, the other metal plate lead terminal 5 electrically connected to the semiconductor chip 4, and a synthetic resin molded body 6 packaging the semiconductor chip 4. <P>SOLUTION: The length and the width of the square land 3 are set 0.65 to 1.35 times as large as those of the semiconductor chip 4, so that the semiconductor chip 4 can be automatically corrected for position by the surface tension of the die bonding agent so as to make its side faces parallel or nearly parallel with those of the square island 3 and accurately positioned at the center of the island. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device using a semiconductor chip, the semiconductor chip is die-bonded to an island part made of a metal plate, and the semiconductor chip is made of a synthetic resin mold part. The present invention relates to a semiconductor device packaged in.

[0002]

2. Description of the Related Art Generally, as is well known in the art, this type of semiconductor device has an island portion integrally formed at the tip of one lead terminal made of a metal plate, and a semiconductor chip is attached to the island portion. Is die-bonded with a die-bonding agent such as solder paste, and at least one other lead terminal also made of a metal plate is attached to this semiconductor chip, and the tip of the other lead terminal is used as a die-bonding agent on the semiconductor chip. Or electrical connection by wire bonding with a thin metal wire, and then the whole of them is molded with a synthetic resin so that the one lead terminal and the other lead terminal protrude from the mold. It is configured to be packaged as follows.

In the semiconductor device having this structure, conventionally,
Although the island part has a rectangular shape similar to the rectangular shape of the semiconductor chip to be die-bonded thereto,
Since the length and width of the rectangle are much larger than the length and width of the rectangle in the semiconductor chip, there are the following problems.

[0004]

That is, an appropriate amount of a die bonding agent such as solder paste is applied on the upper surface of the island portion, and the semiconductor chip is placed on the die bonding agent. When the die bonding agent is melted by heating, the molten die bonding agent spreads over the upper surface of the island portion in four directions, and the semiconductor chips mounted on the molten die bonding agent also move in four directions of the molten die bonding agent. Along with the spread of, the top surface of the island part is moved so as to deviate from its center, and at the position displaced from this center,
It is fixed to the island portion by solidification of the molten die bonding agent.

Further, when the semiconductor chip is supplied to the island portion in a tilted posture in which each side surface of the semiconductor chip is not parallel to each rectangular side surface in the island portion, the tilted posture is corrected. Instead, it is fixed to the island portion in the tilted posture.

Therefore, when a semiconductor chip die-bonded to the island portion is packaged in a synthetic resin mold portion, the size of the mold portion is the same as that of the semiconductor chip packaged in the mold portion. It is expected that the mold part will be displaced from the center, and that each side surface will be in an inclined posture that is not parallel to each side surface of the island part. Since the size of the semiconductor device must be increased, the size and weight of the semiconductor device are increased.

Alternatively, when the size of the mold portion is determined, the size of the semiconductor chip is shifted from the center as described above, and each side surface of the semiconductor chip is different from the island portion. The size must be reduced in anticipation of an inclined posture that is not parallel to the side face, in other words, a large semiconductor chip cannot be used.

The present invention has a technical problem to solve these problems.

[0009]

In order to achieve this technical object, the first aspect of the present invention is that "one lead terminal made of a metal plate integrally provided with a rectangular island portion at the tip and the island. Rectangular semiconductor chip die-bonded with a die bonding agent to at least one portion, at least one other lead terminal made of a metal plate electrically connected to the semiconductor chip, and a synthetic resin for packaging the portion of the semiconductor chip In the semiconductor device including the mold part, the length and width dimensions of the island part rectangle are
The length and width of the rectangle of the semiconductor chip are set to 0.65 to 1.35 times. It is characterized by

According to a second aspect of the present invention, "In the above-mentioned first aspect, the island portion is provided with a recessed portion having a size such that the semiconductor chip is not fitted in the recessed portion. It is characterized by

[0011]

As described above, in the island portion integrally provided on one lead terminal made of a metal plate, the rectangular length and width of the island portion are the same as the rectangular length and width of the semiconductor chip. Since the dimension is set to 0.65 to 1.35 times, the semiconductor chip is mounted on the island portion in a posture in which each side surface of the semiconductor chip is not parallel to each side surface of the island portion. Or, when the semiconductor chip is placed at a position deviated from the center of the island portion, the surface tension of the melted die bonding agent acts on each side surface of the semiconductor chip and the island portion at the same time. As will be described in detail, the self-alignment by the surface tension causes the rectangular semiconductor chip to have a rectangular eye on each side. While being automatically corrected in the direction parallel or substantially becomes parallel orientation with each side of the command unit,
The semiconductor chip is automatically corrected so as to be accurately located at the center of the island portion, and is die-bonded in this posture.

As described above, when the semiconductor chip is die-bonded to the island portion, the deviation from the center of the island portion of the semiconductor chip can be reduced by self-alignment due to the surface tension of the die bonding agent, and the semiconductor chip Since each side surface can be made parallel or close to each side surface in the island portion, the mold portion for packaging this semiconductor chip can be made smaller than in the conventional case, and the semiconductor device can be made smaller and lighter. .

Further, when the size of the mold portion is determined, the semiconductor chip can be made smaller in deviation from the center of the island portion in the semiconductor chip, and each side surface of the semiconductor chip can be formed in the island portion. The size can be increased as much as it can be parallel or close to parallel to each side surface, in other words, a large semiconductor chip can be used.

By the way, in the case where the length and width of the rectangle in the island portion are set to be 0.65 to 1.35 times the length and width of the rectangle of the semiconductor chip, Since the rising height of the die bonding agent applied to the island portion is higher than that when the island portion is not configured as described above, the height position from the island portion in the semiconductor chip becomes higher, Not only are these height positions uneven, but the height of the die bonding agent rises, which deepens the depth of the semiconductor chip's intrusion, which can cause electrical shorts in the semiconductor chip. Become.

On the other hand, the present invention proposes to have the structure of claim 2.

That is, according to a second aspect of the present invention, the island portion is provided with a recessed portion having a size such that the semiconductor chip is not fitted in the recessed portion. Part of the die bonding agent applied to the surface of the portion enters the recessed portion,
The swelling height of the die bonding agent on the surface of the island portion can be lowered under the state where self-alignment is ensured by the die bonding agent, so that the floating height from the island portion in the semiconductor chip can be lowered, It is possible to reduce unevenness in height, and it is possible to reduce the occurrence of electrical shorts in the semiconductor chip due to the shallow depth of penetration of the semiconductor chip into the die bonding agent.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

1 to 7 show a first embodiment.

The first embodiment is applied to a two-terminal type semiconductor device such as a diode.

In the figure, reference numeral 1 denotes a two-terminal type semiconductor device, which is an upper surface of a rectangular island portion 3 integrally provided at the tip of one lead terminal 2 made of a metal plate. Then, a rectangular semiconductor chip 4 is die-bonded, the tip of the other lead terminal 5 also made of a metal plate is die-bonded to the semiconductor chip 4, and the portion of the semiconductor chip 4 is made of synthetic resin. In the molded part 6, the one lead terminal 2 and the other lead terminal 5 are packaged so as to project from the molded part 6.

In the semiconductor device 1 having this structure, since the semiconductor chip 4 is generally a rectangle having a length dimension L0 and a width dimension W0, the island portion 3 is
The length dimension L1 and the width dimension W1 are set to the semiconductor chip 4
The length dimension L0 and the width dimension W0 of the rectangle of FIG.

As shown in FIGS. 3 and 4, an appropriate amount of high melting point solder paste 7 having a melting point of, for example, 310 ° C. is applied to the upper surface of the island portion 3, and then the high melting point solder paste 7 is applied. As shown in FIG. 5, the semiconductor chip 4 is placed on the above, and further, on the upper surface of the semiconductor chip 4,
An appropriate amount of a low melting point solder paste 8 having a melting point lower than that of the high melting point solder paste 7 such as 300 ° C. is applied, and the other lead terminal 5 is applied onto the low melting point solder paste 8. In this state, the molten solder in the solder paste 7 is first solidified and then the molten solder in the solder paste 8 is solidified by heating to a temperature equal to or higher than the solder melting point of the high melting point solder paste 7 and then cooling. .

In this case, the island portion 3
Has a rectangular shape that is congruent or substantially congruent with the rectangular semiconductor chip 4, so that the surface tension of the solder obtained by heating and melting the solder paste 7 simultaneously acts on each side surface of the semiconductor chip 3 and the island portion 3. The rectangular semiconductor chip 4 is attached to the rectangular island portion 3 as shown in FIG.
As shown by the chain double-dashed line, each side surface of the semiconductor chip 4 is placed in a non-parallel orientation with respect to each side surface of the island portion 3, or the semiconductor chip 4 is placed from the center of the island portion 3 from the center. When the semiconductor chips 4 are placed at the displaced positions, the rectangular semiconductor chip 4 is self-aligned by the surface tension of the molten solder.
Is automatically corrected so that each side surface thereof is parallel or substantially parallel to each side surface of the rectangular island portion 3, and the semiconductor chip 4 is accurately positioned at the center of the island portion 3. It will be corrected automatically.

Then, the semiconductor chip 4 is fixed (die-bonded) by solidifying the molten solder in the solder pastes 7 and 8 in the posture corrected as described above.

In this case, according to an experiment conducted by the present inventor, the above-mentioned automatic correction by self-alignment of the surface tension of the heated and melted solder is such that the rectangular length dimension L1 and width dimension W1 of the island 3 are This can be surely achieved when the length L0 and the width W0 of the rectangle of the semiconductor chip 4 are set within the range of 0.65 to 1.35 times, and most preferable is 0.
It was within the range of 75 to 1.25 times.

That is, the rectangular length dimension L1 and width dimension W1 of the island portion 3 are set to the semiconductor chip 4
0.65 of the length L0 and width W0 of the rectangle in
.About.1.35 times the semiconductor chip 4 with respect to the island portion 3 in one of the lead terminals 2.
At the time of die-bonding, the self-alignment of the die-bonding agent can reduce the deviation from the center of the island portion 3 in the semiconductor chip 4, and make each side surface of the semiconductor chip 4 parallel to each side surface of the island portion 3. Alternatively, since they can be brought close to parallel to each other, the width dimension of the mold portion 6 for packaging the portion of the semiconductor chip 4 can be made smaller than in the conventional case, and the semiconductor device 1 can be made smaller and lighter in weight. When the size of the mold portion 6 is determined, the larger semiconductor chip 4 can be used.

Next, FIG. 8 shows a second embodiment.

In the second embodiment, in addition to the structure of the island portion 3 in the one lead terminal 2 as described above, the recess portion 9 is formed in the island portion 3.
Is provided in such a size that the semiconductor chip 4 does not fit in the recess 9.

With this configuration, when the solder paste 7 applied to the surface of the island portion 3 is heated and melted after the semiconductor chip 4 is placed on the solder paste 7, a part of the melted solder is dented. I ’m going to enter Part 9,
As a result, the rising height of the molten solder on the surface of the island portion 3 can be lowered in a state where self-alignment is ensured by the surface tension of the molten solder, so that the semiconductor chip 4 is lifted from the island portion 3. The height can be reduced, unevenness in height can be reduced, and the occurrence of electrical shorts in the semiconductor chip 3 can be reduced.

In the above-described embodiment, in the two-terminal type semiconductor device, the other lead terminal 5 is placed on the upper surface of the semiconductor chip 3 and is die-bonded with a die bonding agent such as the solder paste 8. But that was the case
The present invention is not limited to this, and as shown in FIGS. 9 and 10, a semiconductor chip 4'which is die-bonded to the island portion 3'of one of the lead terminals 2'by a die bonding agent such as a solder paste 7 '. Also in the two-terminal type semiconductor device 1'having a structure in which the other lead terminal 5'is electrically connected by wire bonding with the thin metal wire 10 and then packaged in the mold portion 6 ',
It can be applied to die bonding of the semiconductor chip 4'to the island portion 3 '.

Further, the present invention is not limited to the above-mentioned two-terminal type semiconductor device, and as shown in FIG. 11, the island portion 3a of one of the lead terminals 2a is die-bonded with a die-bonding agent such as solder paste. At least two other lead terminals 5 for the semiconductor chip 4a
a is directly overlaid and connected, and then is packaged in the mold portion 6a, or as shown in FIG.
Wire bonding with a thin metal wire 10a is provided between the semiconductor chip 4 die-bonded to the island portion 3 of one lead terminal 2b with a die bonding agent such as a solder paste, and at least two other lead terminals 5b. In a multi-terminal type semiconductor device such as a transistor having a structure of being electrically connected to the mold part 6b after being packaged in the mold part 6b, it is applied to die bonding of the semiconductor chips 4a and 4b to the island parts 3a and 3b. be able to.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view showing a two-terminal type semiconductor device according to a first embodiment.

FIG. 2 is a plan view of FIG.

FIG. 3 is an exploded perspective view of the two-terminal semiconductor device according to the first embodiment.

FIG. 4 is a sectional view taken along line IV-IV in FIG.

FIG. 5 is a vertical cross-sectional front view showing a state in which a semiconductor chip is placed on an island portion in the first embodiment.

FIG. 6 is a plan view of FIG.

FIG. 7 is a vertical cross-sectional front view showing a state in which a semiconductor chip is placed on the island portion and the other lead terminal is stacked on the semiconductor chip in the first embodiment.

FIG. 8 is a vertical sectional front view showing an island portion according to the second embodiment.

FIG. 9 is a vertical sectional front view showing another two-terminal type semiconductor device to which the present invention is applied.

FIG. 10 is a plan view of FIG.

FIG. 11 is a plan view showing a multi-terminal semiconductor device to which the present invention is applied.

FIG. 12 is a plan view showing another multi-terminal type semiconductor device to which the present invention is applied.

[Explanation of symbols] 1 Two-terminal semiconductor device 2 One lead terminal 3 islands 4 semiconductor chips 5 Other lead terminal 6 Mold part 7,8 Solder paste 9 recess

Claims (2)

[Claims] 1. A lead terminal made of a metal plate integrally provided with a rectangular island portion at a tip thereof, a rectangular semiconductor chip die-bonded to the island portion with a die bonding agent, and an electric wire connected to the semiconductor chip. In a semiconductor device comprising at least one other lead terminal made of a metal plate that is electrically connected and a mold part made of a synthetic resin that packages the part of the semiconductor chip, the rectangular length and width dimensions of the island part Is 0.65 to 1.35 times the length dimension and the width dimension of the semiconductor chip in a rectangle, the semiconductor device using the semiconductor chip. 2. The semiconductor chip according to claim 1, wherein the island portion is provided with a recessed portion having a size such that the semiconductor chip does not fit in the recessed portion. Semiconductor device.