JPS6117138B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in electrodes and wiring patterns on semiconductor device containers.

In high-frequency, high-output transistors, if the emitter inductance is large, the gain decreases, so the conventional method to deal with this problem is to increase the number of emitter wires, provide emitter electrodes on both sides of the transistor chip, and perform wire bonding on both sides. I've been exposed to it. However, due to the structure, it was often necessary for the emitter electrode to cross over with the collector electrode to which the transistor chip was soldered. That is, FIGS. 1 and 2 are a plan view and a cross-sectional view showing an example of a conventional method of assembling a high-frequency, high-output transistor. The electrode 4 is metallized, and a transistor chip 5 is soldered onto the surface of the collector electrode 3. The terminal base electrode 4 of the transistor chip 5 is wire-bonded with a thin metal wire 6, and the emitter electrode 2 is also wire-bonded with a thin metal wire 7.
Wire bonded by. Since the emitter electrode 2 is arranged so as to surround the transistor chip 5, a part where the thin metal wire is bonded crosses over with the collector electrode 3, and this part is crossed over the collector electrode 3 by the bridge 8. It is assembled. There are several ways to construct this bridge, such as integrating it with the emitter lead and embedding the board into a laminate structure, but most of the time, as shown in the figure, the bridge is assembled by itself. . Bridges have become indispensable, especially when high-frequency, high-output transistors are incorporated into hybrid integrated circuits. The bridge 8 is made of pure silver or electrolytic copper plated with gold or silver, and the cost of materials is not negligible.Furthermore, the work of installing the bridge requires skill, which is a factor that reduces work efficiency. I was getting used to it.

One possible method for eliminating this bridge is to separate the collector electrode 3, pass the emitter electrode 2 through the gap, and connect both parts of the collector electrode 3 that sandwich the emitter electrode 2 with a thin metal wire. However, when die bonding the transistor chip 5, the solder flows out. Generally, the electrode surface is plated with gold or silver, but as solder used for die bonding,
Au/S or Au/Ge is used. When this solder is melted by die bonding, the surface is extremely susceptible to oxidation, and wire bonding of gold or aluminum wire to the surface of this oxidized solder requires breaking the surface energy level for metal bonding. Practically impossible. Also, it is not inconceivable to melt the solder and perform wire bonding, but
In the case of gold wire, there is a fear of so-called solder cracking, and it is impossible to do so with aluminum wire. Therefore, it has been difficult to perform die bonding and wire bonding on the same collector electrode.

An object of the present invention is to provide a semiconductor device in which die bonding and wire bonding can be performed on the same electrode surface.

Another object of the present invention is to provide a semiconductor device that eliminates the need for bridge connections at portions where electrodes cross over.

In order to achieve such an object, in the semiconductor device according to the present invention, a non-metalized part is provided in a part of the metalized part of the electrode to which the semiconductor chip is soldered to block the flow of solder, and the non-metalized part is It is sandwiched so that wire bonding can be performed on the side opposite to the die bonding side. The semiconductor device according to the present invention will be explained in detail below using the drawings.

FIG. 3 is a plan view showing an embodiment in which the semiconductor device according to the present invention is applied to a high-frequency, high-output transistor, and FIG. 4 is a cross-sectional view of FIG. 3. In the figure, an emitter electrode 22, a collector electrode 33, and a base electrode 4 are metallized on the surface of a heat conductor insulating substrate 1, and a transistor chip 5 is soldered on the surface of the collector electrode 33 as shown in FIG. , is similar to the high frequency, high output transistor shown in FIG. However, the collector electrode 33 is provided with a slit-shaped non-metalized portion 9 to which electrode metal is not attached, and the collector electrode 3
3 is a die bonding part 3 to which the transistor chip 5 is soldered with this non-metallized part 9 as a border.
3a and wire bond 33b. This wire bonding part 33b is further divided into an internal connection part 33b1 in contact with the non-metallized part 9 and an independent external connection part 33b2, and the bridge part 22a of the emitter electrode 22 passes through the gap between the two separated parts. There is. This bridging portion 22a is connected to the emitter electrode 22
It is metallized on the surface of the insulating substrate 1 integrally with other parts. And this emitter electrode 2
The internal connection part 33b1 and the external connection part 33b of the collector electrode 33 are arranged to sandwich the bridge part 22a of 2.
2 are connected to each other by a thin metal wire 10 that straddles the bridge portion 22a. The transistor chip 5 is electrically connected to the base electrode 4 by a thin metal wire 6, and connected to the emitter electrodes 2 on both sides by thin metal wires 7.
2 is the same as in the case of FIGS. 1 and 2. Hereinafter, the case of assembling the high frequency, high output transistor having the above configuration will be described in detail.

First, by providing the slit-shaped non-metalized portion 9 on the collector electrode 33, even if the transistor chip 5 is soldered at one die bonding portion 33a and the solder flows, the surface of the insulating substrate 1 will be smaller than the electrode metal. Since solder leakage is extremely poor, solder does not flow beyond this non-metalized portion 9 to the wire bond portion 33b on the opposite side. Therefore, no problem occurs in the connection using the thin metal wire at the wire bond portion 33b. Therefore, in the crossover portion between the emitter electrode 22 and the collector electrode 33, the emitter electrode 22 is first continuously formed on the surface of the insulating substrate 1 by metalizing the bridge portion 22a, and then the bridge portion 22a is continuously formed on the surface of the insulating substrate 1. The collector electrode 33 separated by the portion 22a is connected to the bridge portion 2.
Electrical connection can be made by a thin metal wire 10 that straddles 2a. As a result, it is possible to perform wire bonding with the transistor chip 5 using the thin metal wire 7 at the bridge portion 22a without using a bridge, and the separated collector electrode 33 can also be electrically connected without using a bridge. can be reconnected to. Collector electrode 33
Providing or dividing the non-metalized portion 9 into the electrode, or connecting the emitter electrode 22 with the bridge portion 22a, is only a problem in patterning the electrode mask, and does not add any extra man-hours. It is possible to achieve this without any problems.

In the above-mentioned embodiments, a single high-frequency, high-output transistor has been described, but the present invention is not limited to this, and of course can be applied to, for example, a hybrid integrated circuit.

As explained above, according to the semiconductor device according to the present invention, a non-metalized portion is provided in a part of the electrode to prevent solder flow, so that die bonding and wire bonding can be performed on the same electrode with the non-metalized portion as a boundary. It becomes possible to do it with
Even if a part of the electrode is further separated, both separated parts can be easily electrically reconnected using a thin metal wire. Therefore, there is no need to use bridges for assembly even in areas where different types of electrodes cross over, and compared to the case where bridges are used, direct material costs and work time are reduced, making it possible to reduce manufacturing costs. Has excellent effects.

[Brief explanation of the drawing]

1 is a plan view showing an example of a conventional semiconductor device, FIG. 2 is a sectional view of FIG. 1, FIG. 3 is a plan view showing an embodiment of the semiconductor device according to the present invention, and FIG.
The figure is a sectional view of FIG. 3. 1... Insulating substrate, 22... Emitter electrode, 22
a...Bridge portion, 33...Collector electrode, 33a...
...Die bond part, 33b...Wire bond part, 3
3b1...Internal connection part, 33b2...External connection part, 5...Transistor chip, 9...Non-metallized part, 10...Metal thin wire.

Claims (1)

[Claims] 1. A non-metalized part for preventing solder flow is provided on a part of a metalized electrode on a container for a semiconductor device, and one part of the electrode with the non-metalized part as a border is used as a die-bonding part and a part other than the non-metalized part. A semiconductor device characterized in that the other part continuous to the die bond is a wire bond part, a semiconductor chip is bonded to the die bond part, and a thin metal wire is bonded to the wire bond part.