JPS609343B2 - Electronic component manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing electronic components using connections mediated by molten metal.

Conventionally, electronic components have been connected by placing the bonded electronic component and the electronic component to be bonded in appropriate positions at room temperature in advance, and then applying a load to press or weld them.

Alternatively, electronic components were connected by storing the device under a load at a high temperature until the adhesive metal melted, and then returning it to room temperature. These methods have disadvantages such as excessive loads being applied to the pressure saddle and welded parts, resulting in cracks or distortions in the joints, as well as problems such as being stored at high temperatures for too long, and high temperatures in areas other than the joints. Because they are long, they have the disadvantage that they deteriorate and cannot be used in cases where they cannot be stored at high temperatures for long periods of time. An object of the present invention is to provide a method for manufacturing electronic components that does not have these conventional drawbacks.

A feature of the present invention is that, in a method for manufacturing electronic components in which connections are made using molten metal, the molten metal is preheated to a temperature below the melting temperature and above room temperature, and then the molten metal and the electronic components to be bonded are bonded together. The electronic components to be bonded are bonded under pressure at a high temperature higher than the melting temperature of the molten metal, and then the molten metal and the electronic components to be bonded are bonded under pressure for a certain period of time at a temperature lower than the melting temperature of the molten metal and at the melting temperature. The electronic component is manufactured by maintaining the temperature at a temperature close to that of the conventional one, and then releasing the pressurized state to bring the temperature to room temperature.

According to the present invention, since the molten metal is preheated, the bonding time can be shortened.

Furthermore, since the pressurized state is maintained for a certain period of time even after bonding, and the temperature is kept close to the melting temperature, the bonded part is not rapidly cooled and cracks do not occur, making it possible to maintain a sufficiently stable bonded state. . Embodiments will be described below with reference to the drawings.

Embodiment 1 FIG. 1 shows a semiconductor element 3 having an Au protruding electrode 6 placed on a support base 2, a surface (Sn) plated frame 4 placed opposite to the electrode 6, and a board frame 4 thereon. FIG. 2 is a sectional view of the relative arrangement of a pressurizing section 1 that heats and presses objects.

In this state, at least pressurizing part 1 or pressurizing part I
Then, the lead frame 4, or the pressurizing part 1, the copper lead frame 4, and the semiconductor element 3 are held at 200:00 for 1 second at a temperature at which the Au-Sn eutectic alloy does not melt, and then the pressurizing part 1 is pressed down and held in the state shown in Fig. 2, and at the same time, the temperature of the pressurizing part 1 is held for 0.9 seconds at 300 qC, the temperature at which the gold-tin alloy completely melts, by flowing an electric current. A gold-tin alloy 7 is formed by the tin plating 5 on the lead frame 4 and the gold protruding electrodes 6 of the semiconductor element 3. Then,
The gold-tin alloy 7 is completely solidified by lowering the temperature of the pressurized part to 200 C0 by applying 1.9 kg of sand, and the connection between the semiconductor element 3 and the lead frame 4 is obtained, and then it is cooled to room temperature. . In addition, this cooling to 200qC was done with the initial 0.9 sand to almost 200 qC, and this 20
Maintain the temperature near 0°C for 1 second. FIG. 3 shows the relationship between temperature and time in this process.

FIG. 4 shows a cross-sectional view of the semiconductor device whose connections have been completed in this step.

Example 2 This example shows a method for sealing an enclosure case for a semiconductor device, and is shown in FIGS. 5 and 6.

FIG. 5 shows a pressurizing part 11, a ceramic case base 12
, the internal metallized wiring 18 of the case, the semiconductor element 17 connected to the metallized wiring 18 by the bonding wire 16, the external lead 19, the Au layer 15 provided in the sealing part of the case base 12, and the sealing lid of the case. 1 3
and the relative positions of the sealing metal layer 14 are shown. In this example, if the same steps as in Example 1 are followed, a sealed semiconductor device as shown in FIG. 6 can be easily obtained. The sealing part 10 in FIG. 6 is made of a gold-tin alloy of the metal layers 14 and 15 in FIG. In addition, the same number indicates the same thing. As shown in the embodiments above, the present invention allows a simple and stable connection to be obtained in a short time.

It is clear that the present invention can be applied to the manufacture of other electronic components other than those shown in the examples.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the relative positions of a pressurizing part, a lead frame, a semiconductor element, and a support base. FIG. 2 is a cross-sectional view of the lead frame and the semiconductor element being connected. FIG. 3 is a diagram showing the relationship between temperature rise of the pressurizing section and time. FIG. 4 is a cross-sectional view of the semiconductor device after the connection is completed. FIG. 5 is a cross-sectional view of the relative positions of the case lid, the case base, and the pressurizing part when the semiconductor enclosure case is sealed. FIG. 6 is a cross-sectional view of the semiconductor device after encapsulation. 1, 11... Pressure part, 2... Support stand, 3, 17
... Semiconductor element, 4... Lead frame, 5... Sn plating, 6... Au protruding electrode, 7,1 0... Au-S
n alloy, 12... Ceramic case, 13... Case sealing lid, 1 4... Sealing metal layer, 1 5... Au
Layer, 1 6... Bonding line, 18... Metallized wiring, 19... External lead. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 5

Claims (1)

[Claims] 1. In a method of manufacturing an electronic component in which connection is made using molten metal, the molten metal is preheated to a temperature below the melting temperature and above room temperature, and then the molten metal and the electronic component to be bonded are bonded to the molten metal. The electronic components to be bonded are bonded under pressure at a high temperature higher than the temperature, and then the molten metal and the electronic components to be bonded are bonded under pressure for a certain period of time at a temperature below the melting temperature of the molten metal and close to the melting temperature. A method for manufacturing an electronic component, characterized by maintaining the temperature at a certain temperature, and then releasing the pressurized state and bringing the temperature to room temperature.