JPS639664B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a semiconductor device, and more particularly to a structure of an element storage capacity (package) with improved dissipation of heat generated from a semiconductor element.

Gallium-arsenide field-effect transistors (GaAsFETs), which are a type of semiconductor device, have the advantage of being able to be used in higher frequency ranges than semiconductor devices that use silicon Si as the semiconductor material. . However, the base material, gallium and arsenic, has lower thermal conductivity (higher thermal resistance) than silicon, making it difficult to handle large amounts of power and output. In other words, while the thermal conductivity of silicon is 1.5 [W/cm・℃],
The thermal conductivity of gallium and arsenic is about 0.4 [W/cm・℃].

Therefore, in addition to the device fixing structure shown in FIG. 1, for example, as a means for improving the heat dissipation property of the GaAsFET and increasing the power and output of the GaAsFET, as shown in FIG. A so-called upside down mount structure has been proposed.

In Figure 1, 11 is a GaAsFET element, 12
is a metal base made of oxygen-free copper on which the GaAsFET element 11 is mounted and fixed. The metal base 12 constitutes a heat sink and a source electrode of the GaAsFET. That is, the source electrode of the GaAsFET 11 is electrically connected to the metal substrate 11 by a conventional lead wire or a metallization layer extending on the sides of the GaAsFET device 11. Reference numeral 13 denotes a ceramic insulator frame disposed on the metal base 12 so as to surround the GaAsFET element 11, and on its surface are lead wires 14A led out from the gate electrode and drain electrode of the GaAsFET element 11. ，
Metallized layers 15A and 15B to which 14B is connected
will be placed. Further, 16 is a ceramic insulator frame for airtight sealing disposed on the insulator frame 13, and a lid 17 made of metal or ceramic is disposed on the top surface of the insulator frame 16 to cover the GaAsFET element 11. Hermetically sealed. Furthermore, 18A and 18B are located outside the insulator frame 16, and are connected to the metallized layer 1.
These are external connection terminals connected and fixed to 5A and 15B.

In such a structure, GaAsFET element 1
The heat emitted from the active area on the surface of
It is conducted to the metal substrate 12 through the substrate of the GaAsFET device. However, as described above, since the GaAs substrate has low thermal conductivity, it is difficult to increase the power and output of the GaAsFET.

For this reason, an element mounting and fixing structure as shown in FIG. 2 has been proposed. In this figure, the same parts as those shown in FIG. 1 are given the same reference numerals.

In the structure shown in Figure 2, the GaAsFET
For example, the source electrode of the element 11 is a thick plated body 2 of gold.
1, the GaAsFET element 11 is reversed from the structure shown in FIG. 1, and the thick gold plated electrode 21 is fixed to the metal base 12.

According to such a structure, the GaAsFET element 11
The heat generated from the active region of the thick gold plated electrode 2
1 to the heat dissipation base 11. However, in such a structure, there is a limit to increasing the cross-sectional area of the thick gold plated electrode 21, and a sufficient heat dissipation effect cannot be expected.

The present invention aims to provide a semiconductor device having a structure capable of more effective heat dissipation in place of such a conventional structure.

Therefore, according to the present invention, there is provided a metal base, a semiconductor element fixed on the metal base, the insulator member disposed on the metal base and surrounding the semiconductor element, and the insulator member disposed on the insulator member. In the semiconductor device, a desired electrode of the semiconductor element is formed to protrude above an active region of the semiconductor element, and a conductive thin film is disposed in contact with the protruding electrode, A semiconductor device is provided in which a conductive member is filled between the conductive thin film and the lid member.

Hereinafter, the present invention will be explained in detail using examples. FIG. 3 shows the structure of an embodiment of a semiconductor device according to the present invention.

In Fig. 3, 101 is a GaAsFET element, 1
02 is a metal base made of oxygen-free copper on which the GaAsFET element 101 is mounted and fixed. The metal base 10
2 constitutes a heat sink. Then, connect the source electrode of the GaAsFET element 101 to the lead wire or
If connected by a metallization layer extending on the sides of the GaAsFET device 101, the metal substrate 102
It constitutes the source electrode of the GaAsFET element 101.

Moreover, 103 is the above-mentioned on the metal base 102.
This is a ceramic insulator frame arranged to surround the GaAsFET element 101, and its surface has the above-mentioned
Lead wires 104A and 104B derived from the gate electrode and drain electrode of the GaAsFET element 101
Metalized layers 105A and 105B to which are connected are provided.

Further, 106 is a ceramic insulator frame for airtight sealing arranged on the insulator frame 13, and a lid 107 made of metal, for example, copper, is arranged on the top surface of the insulator frame 106, so that the GaAsFET element 101 can be air-tightly sealed. sealed.

Furthermore, 108A and 108B are the insulating frame 10.
6, the metallized layer 105A,
This is an external connection terminal made of Kovar that is connected and fixed to 105B.

In the present invention, the GaAsFET element 101
The source electrode is composed of a thick gold plated body 109. Further, a metal thin film 110 made of gold or the like having a thickness of 20 to 100 [μm] is disposed in contact with the source electrode 109 from near the top of the hermetic sealing insulator frame 106 . The metal thin film 110 is connected to the source electrode 109 by thermocompression bonding, and its peripheral portion is thermocompression bonded and fixed to a metallized layer (not shown) provided on the sealing insulator frame 106. Furthermore, in the present invention, the metal thin film 110 and the lid 10
In the space between 7 and 7, a resin 1 with good thermal conductivity, such as a conductive epoxy resin mixed with metal Ag particles, is placed.
11 is filled.

Here, when assembling the semiconductor device,
Prior to attaching the lid 107, the metal thin film 1 is
10 and the resin 111 is filled.

Furthermore, in the present invention, the lid 107 is provided with an external mounting stud 112,
The stud 112 is inserted into a through hole 114 provided in the heat sink 113 and is further configured to be mechanically fixed to the heat sink 113 by a nut 115.

According to the present invention, the GaAsFET element 1
The source electrode 01 is led out in two directions: to the base metal substrate 102, through the metal thin film 110, the synthetic resin layer 111, and the lid 107 to the stud 112.

Then, the heat generated from the active region of the GaAsFET element 101 is transferred to the GaAsFET element 101.
through the base of the metal base 102 and the metal base 1
02 is conducted to the heat sink 116 to which it is fixed, and is also conducted to the heat sink 113 through the thick plating electrode 109, the thin metal film 110, the resin 111, the lid 107, and the stud 112.

Therefore, according to the present invention, the above-mentioned FIGS.
Approximately twice the heat dissipation performance can be obtained compared to the structure shown in the figure. For example, in a GaAsFET with a high frequency output of 3 [W], this makes it possible to lower the temperature of the active region by about 50 [°C] compared to the conventional structure.
It is extremely effective in increasing the output and reliability of GaAsFET devices.

It should be noted that the present invention is not limited to the above embodiments, and if an electrode other than the source electrode is used as the ground electrode, a thick plating electrode may be formed on the ground electrode.

Furthermore, instead of the metal thin film, a synthetic resin film whose surface has been metallized can also be used. Electrical connection between the metallized layer on the surface of the synthetic resin film and the lid can be made through the resin 111 and the metallized layer of the synthetic resin film fixed to the insulator frame 103 .

Further, instead of the resin 111, a low melting point metal such as solder may be filled.

Furthermore, the heat sinks 113 and 116 may be integrated. If the heat sinks 113 and 116 are integrated, the ground potential can be made constant.

[Brief explanation of the drawing]

1 and 2 are cross-sectional views showing the structure of a conventional semiconductor device. FIG. 3 is a sectional view showing the structure of a semiconductor device according to the present invention. In the figure, 11,101...semiconductor element, 1
2,102...Metal base, 13,103...Insulator frame, 16,106...Insulator frame for sealing, 1
7,107... Lid, 21,109... Metal thick plating layer, 110... Conductive thin film, 111... Resin,
112...Stud.

Claims (1)

[Claims] 1 comprising a metal base, a semiconductor element fixed on the metal base, an insulator member disposed on the metal base and surrounding the semiconductor element, and a lid member disposed on the insulator member. In the semiconductor device, a desired electrode of the semiconductor element is formed to protrude above an active region of the semiconductor element, a conductive thin film is disposed in contact with the protruding electrode, and the conductive thin film and the lid member are disposed in contact with the protruding electrode. A semiconductor device characterized in that a conductive member is filled between the semiconductor device and the semiconductor device.