JPS63283033A - Die bonding method - Google Patents

Abstract

PURPOSE:To eliminate the need of using any bonding member such as eutectic solder or the like and to prevent short circuit between electrodes, by forming plated gold electrodes for an electronic or electric component from a thick plated gold layer, and exerting a pressure as required on the component from the back thereof while heating the same, for thermocompression bonding the component to a circuit pattern. CONSTITUTION:Plated gold electrodes are formed thick enough on the opposite sides of a single-plate ceramic capacitor 1. The capacitor 1 is mounted on a circuit pattern as required on a thin film substrate 2. The substrate 2 is mounted on a hot plate 4 heated to a temperature of 300-320 deg.C so that all of them are heated. A wedge 3 is applied against the upper electrode of the capacitor 1 and a load is exerted to press the capacitor 1 against the substrate 2. According to this method, there is no need of using any bonding member such as eutectic solder or the like and, therefore, the short circuit between the electrodes can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a die bonding method for electronic/electrical components mounted by die bonding, such as single-plate ceramic capacitors.

[Conventional technology]

Conventionally, a method shown in FIG. 2 has been used to bond a single-plate porcelain capacitor, in which electrodes are formed by gold plating or the like on both sides of a single-plate porcelain plate, onto a circuit pattern on a thin film substrate. That is, eutectic solder 13 is attached to one side of the gold-plated electrode of the single-plate ceramic capacitor 11 and placed on a predetermined circuit pattern of the thin film substrate 12, while the thin film substrate 12 is placed on the hot plate 14. In this method, the single-plate ceramic capacitor 11 is bonded to the thin film substrate 12 by heating and melting the eutectic solder 13 by the heat.

[Problems to be Solved by the Invention] In the above-described conventional die bonding method using eutectic solder, if a ridge of the gold-plated electrode is formed on the side surface of the single-plate ceramic capacitor 11, the eutectic solder 13 will move along the edge. There is a problem in that the metal layer creeps up to the upper gold-plated electrode, causing a short circuit between the two electrodes.

Furthermore, when bonding is performed on a circuit pattern with dimensions smaller than the gold-plated electrodes of the single-plate ceramic capacitor 11, the eutectic solder 13 overflows and spreads to the surrounding area, flowing to the surrounding wire bonding points and interfering with wire bonding. There is also the problem of overheating, which has a negative impact on production yields.

SUMMARY OF THE INVENTION An object of the present invention is to provide a die bonding method that solves the above-mentioned problems such as short circuits between electrodes and the inability to perform wire bonding at peripheral positions, and enables good bonding.

[Means for solving problems]

In the die bonding method of the present invention, a gold-plated electrode to be provided on an electronic/electrical component is formed with a thick gold-plated layer, and the electronic/electrical component is pressed from behind with a required pressure while this gold-plated layer is in contact with a circuit pattern. By heating and thermocompression bonding to the circuit pattern, an adhesive member such as eutectic solder is not required, and short circuits between electrodes and effects on the surrounding area caused by the adhesive member are prevented.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a diagram showing an embodiment of the die bonding method of the present invention.

In this method, gold-plated electrodes are first provided on both sides of a single-plate ceramic capacitor 1, and the gold plating is applied to a sufficiently thick layer (
10 to 12 μm).

Then, the single-plate ceramic capacitor 1 configured as described above is placed on the desired circuit pattern of the thin film substrate 2. At the same time, the thin film substrate 2 is placed on a hot plate 4 heated to a temperature of 300 to 320°C, and the whole is heated.

Then, a sapphire wedge 3 having a rectangular shape similar to the size of the single-plate ceramic capacitor 1 is brought into contact with the upper electrode part of the single-plate ceramic capacitor 1, and a load of 1 to 3K is applied to the wedge 3.
By adding g/mm2, the single plate porcelain capacitor 1 is connected to the thin film substrate 2.
to be pressed.

As a result, the gold-plated layer of the gold-plated electrode on the lower surface side of the single-plate ceramic capacitor 1 is melted and bonded to the circuit pattern of the thin-film substrate 2 by thermocompression bonding, and the single-plate ceramic capacitor 1 itself is fixed to the thin-film substrate 2.

Therefore, according to this method of die bonding, the single-plate porcelain capacitor 1 is bonded by melting the gold plating layer of a sufficiently thick gold-plated electrode with heat and pressure and thermocompression bonding to the circuit pattern of the thin film substrate 2. Because
There is no need to use adhesive materials such as eutectic solder, and there is no possibility of short circuits between the electrodes caused by this type of adhesive material. Moreover, this type of adhesive material does not overflow and spread into the wire bonding area around the capacitor, and it is also possible to effectively prevent wire bonding from occurring.

In the embodiment, an example in which the present invention is applied to a single-plate ceramic capacitor has been described, but the present invention can be similarly applied to die bonding of electronic/electrical components having the same or similar shape.

〔Effect of the invention〕

As explained above, in the present invention, the gold-plated electrodes of electronic and electrical components are formed with a thick gold-plated layer, and the electronic and electrical components are pressed from behind with the required pressure and heated to thermocompression bond them to the circuit pattern. Eliminates the need for adhesive materials such as crystal solder,
In addition to preventing short circuits between electrodes caused by this adhesive material, it also eliminates problems with wire bonding caused by the adhesive material spreading around the die bonding material, thereby achieving good bonding and making it possible to It is possible to improve the yield of hybrid ICs equipped with die bonding members.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing the bonding method of the present invention, Fig. 2 is a perspective view showing the bonding method of the present invention;
The figure is a perspective view showing a conventional bonding method. 1.11... Single plate ceramic capacitor, 2, 12... Thin film substrate, 3... Wedge, 4.14... Hot plate, 13... Eutectic solder.

Claims (1)

[Claims] (1) In a die bonding method for electronic/electrical components that has gold-plated electrodes on both sides and directly bonds one side to a circuit pattern on a board, the gold-plated electrode is formed with a thick gold-plated layer, and this gold-plated layer is used as a circuit pattern. A die bonding method characterized in that the electronic/electrical component is pressed from behind with a predetermined pressure while in contact with the electronic/electrical component and heated to bond the electronic/electrical component to the circuit pattern by thermocompression.