JPH0311565A - Connecting configuration for electrodes - Google Patents

Abstract

PURPOSE:To enable electrodes to be joined with no stress accompanied by sealing a pair of the electrodes while liquid metal is intervened between them. CONSTITUTION:An electrode 2 is formed on the substrate 1 of a semi-conductor integrated circuit while being patterned. Another electrode 4 to be connected with the electrode 2 is formed on a substrate 3 made of a material such as ceramics and the like. A film is formed by covering the top of the substrate 3 with a synthetic resin layer 8 while the film is half hardened. An opening 9 is made by a hot etching process at a position corresponding to the electrode 2 of the semi-conductor integrated circuit 1 in the synthetic resin layer 8. A liquid metal 5 is filled in over the electrode 4 exposed out of the opening 9 of the substrate 3. The electrodes 2 and 4 in the substrates 1 and 3 are finally aligned in position while the synthetic resin layer 8 is completely hardened, it is concurrently accelerated that the synthetic resin layer 8 and the electrode 4 are closely adhered to the substrate 3 and a conductor 4a respectively. In this case, the substrates 1 and 3 may be pressed with pressure in the proximity direction in order to improve adhering strength thereon.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is applied to an IC (integrated circuit).
The present invention relates to an electrode connection structure suitably implemented for electrically connecting an integrated circuit board on which a semiconductor element such as a circuit board (such as an integrated circuit board) is formed, and a circuit board such as a printed circuit board, a flexible board, or a ceramic board.

Conventional technology In the connection of each electrode between a semiconductor integrated circuit board such as an IC and a circuit board on which it is mounted, W B (
1'1ire Dondi+1g) method, T A B
(TapeAuLotnaLedDonding) method, F (?, Flip Chip) method, etc.In recent years, the FC method has been adopted, which is advantageous in terms of reducing the mounting area, shortening the connection time, and shortening the connection length. Attention has been paid.

The FC method is a semiconductor integrated circuit board such as an IC that is provided with protruding electrodes called bayu-pu made of solder metal material, etc., facing the other circuit board, and the protruding electrodes are heated and melted. This structure connects to the electrode of the other circuit board.

Problems to be Solved by the Invention In connection between side boards using the conventional FC method, there are two steps: (1) forming a barrier and a metal layer on one board, and forming a bump using a solder metal material, and (2) applying a parent solder metal to the other board. At least two steps including the forming step are required, resulting in high cost.

Regarding the bonding strength at the time of contact 6, although the metal radical bonding between the solder metal and the parent solder metal is strong, internal stress is generated due to the bonding between the solder metal and the parent solder metal, and the difference in expansion coefficient between the side substrates. Due to the generation of stress in the connection part due to thermal stress caused by
There was an element of instability in terms of reliability.

The object of the present invention σ) is to provide an electrode connection structure with excellent productivity and improved reliability.

Means for Solving the Problems The present invention is an electrode connection structure characterized in that a pair of electrodes to be connected are sealed with a liquid metal interposed between them.

Function According to the present invention, a liquid metal is interposed between a pair of electrodes to be connected, thereby electrically conducting the pair of electrodes. ), reducing wire bonding processes such as wire positive connection methods,
It is possible to reduce the bump forming process in the current flip chip bonding method, and furthermore, it is possible to bond a stress-free structure, that is, a structure in which no stress is generated. Therefore, productivity is improved and contact reliability is also improved.

Example FIG. 1 is a sectional view of one embodiment of the present invention.

The electrode 2 made of a metal material such as AN-3i, which is formed on the - side substrate 1 of a semiconductor integrated circuit, is made of a material 1'E+, such as ceramic, on which the substrate 1 of the semiconductor integrated circuit is mounted. The electrode 4, which is a conductor of the substrate 3F of the other 1-), is electrically connected via the liquid metal 5. This liquid metal 5 is, for example, mercury.

The liquid metal 5 is sealed with a sealing member 8 made of an electrically insulating resin material or the like.

The electrode connection structure shown in FIG.
I\\ with reference to 21. First, as shown in FIG. 2(1), electrodes 2 are patterned on a substrate 1 of a semiconductor 4A multilayer circuit. Another electrode 4 to be connected to the electrode 2 is formed on a substrate 3 made of a ceramic material. This electric f! 4 is, for example, AN
2, Ti, Cu, NiT j /W, etc. Such an electrode 4 is patterned by etching, printing, or the like. The electrode 4 extends and is wired in series with the wooden conductor 4a. In order to electrically connect the electrode 2.4, as shown in FIG. 2 (2), the electrode 4 and the conductor connected thereto = 18 on the substrate 3, and the electrode 4 and the conductor 4εt are not formed. The remaining region 7 is coated with the 6-component resin M8 over the entire surface. This six-component resin layer 8 is made of a six-component resin material that undergoes a curing reaction by heat, ultraviolet rays, electron beams, etc., and is formed by a spinning method, a spray method, a day rough method, or the like. After forming the curing resin layer 8 in this manner, heat, ultraviolet rays, etc. are applied to promote the curing reaction to bring it into a so-called semi-cured state.

Thereafter, as shown in FIG. 2(3), the electrode 4 corresponding to the electrode 2 of the semiconductor circuit board 1 is opened in the resin layer 8 as shown in FIG. Open and expose.

When the synthetic resin layer 8 is a thermosetting polyimide resin, it is heated to 120 to 150'C to make it into a semi-cured state, and then heated with an alkaline liquid or a J hydrazine liquid through a resistor. Then, an opening 9 is formed to expose the electrode 4.

In addition, when the molded resin layer 8 is an ultraviolet curable resin, such as silicone, photosensitive polyimide, or photosensitive acrylic resin, it may be irradiated with ultraviolet light for a short period of time to bring it into a semi-cured state. An opening 9 is formed using an etchant solution to expose the electrode 4.

Therefore, in the state shown in FIG. 2(3), the liquid metal 6 is filled onto the electrode 4 exposed through the opening 9 of the substrate 3 by a printing method or by a so-called dispenser method in which it is supplied from an elongated nozzle.

Finally, position the electric fi 2.4 of the substrates 1 and 3, apply heat if the molded resin layer 8 is a thermosetting type, or apply ultraviolet light if it is an ultraviolet curable type. While fully curing the synthetic resin layer 8, promoting adhesion between the substrate 1 and the six-synthetic resin R8, and promoting adhesion between the synthetic resin layer 8, the substrate 3, the electrode 4, and the conductor 4a,
Improves adhesion strength. At the time of this close contact, the substrates 3 may be pressed in the direction toward each other in order to improve the strength of the close contact. , 2, the substrates 1 and 3 are mechanically integrated, and the electrodes 2 and 4 are electrically connected via the liquid metal 5.

Compared to the conventional flip-flop board, the tM formation reduces costs by eliminating the need for a bumping process and by eliminating the need to form a parent solder metal pattern on the board. reduction is possible. moreover,
During solder buffer fabrication, during bump formation with solder plating acid and connection to the integrated circuit, the contact area and the gap between the wire electrodes 2 and 4 are made stress-free, so there is no stress. This makes it possible to improve reliability.

In place of the six synthetic resin layer S, an electrically insulating material may be used.

Effects of the Invention As described in Section 2, according to the present invention, a liquid metal is interposed between a pair of electrodes to seal them, and the pair of electrodes are electrically conductive, so manufacturing is easy. This reduces productivity, but there is no stress generated in the electrodes, which improves reliability.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of an embodiment of the present invention, and FIG. 2 is a cross-sectional view showing the manufacturing process of the embodiment shown in FIG.

Claims (1)

[Claims] An electrode connection structure characterized in that a pair of electrodes to be connected are sealed with a liquid metal interposed between them.