JPH04253348A - Method for connecting lsi chip - Google Patents

Abstract

PURPOSE:To enable an LSI chip to be connected highly thinly and positively by placing an adhesive layer where a conductive particle is dispersed only between an electrode pad and an electrode terminal and then performing thermocompression connection of an insulation portion by placing an adhesive which does not include the conductive particle. CONSTITUTION:A resin with both a photo-setting and a thermosetting properties is coated on an LSI chip 1, is dried, and then subjected to ultraviolet rays exposure. At this time, a resin layer on an electrode pad 2 is provided with glare protection. A solution where a conductive particle is dispersed within the resin with both the photo-setting and thermosetting properties is coated on a board 3, is dried, and then subjected to ultraviolet rays exposure. At this time, a resin layer of an electrode terminal 4 is exposed. Then, development is made and then a masking pattern is created by eliminating the resin layer on the LSI chip and the board 3. Then, the electrode pad 2 and the electrode terminal 4 are allowed to face each other, the LSI chip 1 is placed on the board 3, the voltage pad 2 and the electrode terminal 4 are adhered, the LSI chip 1 is pressed and heated, thus enabling the LSI chip 1 and the board to be adhered and fixed.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to connection and mounting between fine electrodes such as LSI chips and electrodes provided on a mounting board.

0002

[Prior Art] Conventionally, as this type of anisotropic conductive material for electrical connection, an adhesive composition containing conductive particles forming a conductive metal thin layer on the surface of a polymeric material has been used. The connection temperature is 20-30℃ at 180-200℃.
A thermocompression bonding method of approximately kg/cm2 was used.

A conventional mounting method will be explained below. FIG. 3 is a cross-sectional view of a substrate showing a conventional LSI chip connection method in the order of steps. The connections of this LSI chip are as follows. That is, as shown in FIG. 3(a), an LSI chip 1 having electrode pads 2 formed thereon and a substrate 3 having electrode terminals 4 formed corresponding to the electrode pads 2 are separated by dispersing conductive particles 9. They face each other with a thermal adhesive resin 11 contained therebetween. Next, as shown in FIG. 3(b), LS
The I-chip 1 is pressed against the substrate 3 and heated to soften the thermal adhesive resin 11, and the electrode pads 2 and the electrode terminals 4 are connected by the conductive particles 9.

0004

[Problems to be Solved by the Invention] According to the conventional connection and mounting method described above, when the number of conductive particles electrically connecting an electrode pad and an electrode terminal increases, the adjacent electrode pad or electrode terminal A short circuit or current leak occurs between the two. If the number of conductive particles is reduced in order to avoid this, the problem arises that the connection resistance increases and varies. Furthermore, in extreme cases, some connections may become electrically open. Furthermore, this trend is becoming more and more noticeable as the connection dimensions have become increasingly finer in recent years. In addition, it is extremely difficult to press the LSI chip and the substrate while keeping them strictly parallel, which causes variations in the gap between each electrode terminal, and variations in the number of conductive particles between each electrode terminal, resulting in poor connection. There was a problem with stability. These phenomena are serious drawbacks that cause device malfunctions.

[0005] The object of the present invention is to have good reproducibility, stability,
Moreover, it is an object of the present invention to provide a method for connecting LSI chips that can achieve high definition.

[0006]

[Means for Solving the Problems] In order to achieve the above object, in the connection mounting method according to the present invention, electrode pads formed on an LSI chip and electrode terminals formed on a substrate corresponding to the electrode pads are provided. A method for connecting an LSI chip, which involves applying a solution of conductive particles dispersed in a thermosetting resin that is cured by active energy rays to one of the surfaces of the LSI chip or the substrate, and then dried. a step of applying a thermosetting resin that is cured by active energy rays to the surface of the substrate or one side of the LSI chip on which the solution in which the conductive particles are dispersed is not applied, and then drying the LSI chip; and a step of removing the adhesive resin on the surface of the substrate by lithography and development, and a step of facing the electrode pad and the electrode terminal, closely bonding the semiconductor circuit element and the substrate, and then curing by thermocompression bonding. .

[0007]

[Function] Good reproducibility, stability, high connection reliability, and high definition.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be explained with reference to the drawings. 1A and 1B show an LSI as an embodiment of the present invention.
FIG. 3 is a cross-sectional view showing a method for connecting chips in order of steps. FIG. 2 is a cross-sectional view of an LSI chip connected by the method of the present invention. First, as shown in FIG. 1A (a), electrode pads 2 are formed on the surface of an LSI chip 1, and a substrate 3 is formed on the surface of an LSI chip 1.
Electrode terminals 4 are formed in correspondence with the electrode pads 2.

In the present invention, as shown in FIG. 1A (b), a resin having both photocurability and thermosetting properties is uniformly applied onto the LSI chip 1 using a spinner or the like, and then dried. Next, UV 7 exposure is performed by photolithography. At this time, exposure is performed while shielding the resin layer on the electrode pad 2 from light. As shown in FIG. 1A (c), on the substrate 3,
A solution in which conductive particles are dispersed in a resin that has both photocurability and thermosetting properties is uniformly applied using a spinner or the like, and then dried. Next, UV 7 exposure is performed by photolithography. At this time, the resin layer of the electrode terminal 4 is exposed. In the examples, "Pimel" (trade name) manufactured by Asahi Kasei Corporation, which is a polyimide precursor having a photosensitive group (negative type), was used, and as the conductive particles, "Micro Pearl" (manufactured by Sekisui Fine Chemical Co., Ltd.) was used. (product name) was used. Next, as shown in FIG. 1B (d), development is performed using a developer 10 to remove the resin layer on the LSI chip and the substrate 3 to create a mask pattern. Next, as shown in FIG. 1B (e), the electrode pad 2 and the electrode terminal 4 are faced to each other.

Next, the LSI chip 1 is placed on the substrate 3 with the electrode pads 2 and electrode terminals 4 facing each other, and the electrode pads 2 and 4 are placed facing each other.
and the electrode terminal 4 are brought into close contact with each other. Furthermore, 10kg/
By pressing down the LSI chip 1 by applying a load of about cm2 and simultaneously heating it to about 250°C, the resin placed between the LSI chip and the substrate 3 is cured, and the LS
The I-chip 1 and the substrate 3 are bonded and fixed.

[0011] A photosensitive and thermosetting resin is applied to the substrate 3, and a solution in which conductive particles are dispersed in the photosensitive and thermosetting resin is applied to the LSI chip 1. The connection may be made according to the following.

0012

As explained above, in the LSI chip connection method of the present invention, an adhesive layer in which conductive particles are dispersed is disposed only between the electrode pad and the electrode terminal using lithography technology, and the insulating part is With lithography technology,
Since the adhesive layer containing no conductive particles is arranged and the connection is made by thermocompression, a very remarkable effect can be obtained in that high-definition connection can be reliably, easily and reliably performed.

[Brief explanation of the drawing]

FIG. 1A is a cross-sectional view showing the first stage of the LSI chip connection method according to the present invention in the order of steps;

FIG. 1B is a cross-sectional view showing the latter stages of the LSI chip connection method according to the present invention in the order of steps.

FIG. 2 is a cross-sectional view of an LSI chip connected by the method of the present invention.

FIG. 3 is a cross-sectional view showing a conventional LSI chip connection method in the order of steps.

[Explanation of symbols]

1 LSI chip 2 Electrode pad 3 Substrate 4 Electrode terminal 5 Photosensitive and thermosetting resin 6 Photomask 7 Ultraviolet light 8 Light and thermosetting resin 9 containing conductive particles dispersed therein Conductive particles 10 Developing solution 11 thermal adhesive resin

Claims (1)

[Claims] 1. An LSI chip connection method for connecting an electrode pad formed on an LSI chip and an electrode terminal formed on a substrate corresponding to the electrode pad, the method comprising:
A step of coating one of the surfaces of the SI chip or the substrate with a solution in which conductive particles are dispersed in a thermosetting resin that is cured by active energy rays, and then drying the solution; A step of coating the uncoated surface of the substrate or one of the LSI chips with a resin that is cured by active energy rays and having thermosetting properties, and then drying the surface, and applying the adhesive resin on the LSI chip and the surface of the substrate by lithography and development. A method for connecting an LSI chip, comprising the steps of: removing the electrode pads and electrode terminals, bringing the semiconductor circuit element and the substrate into close contact with each other, and then thermocompression bonding and curing.