JPS62158336A - Mounting structure of electronic parts and their mounting method - Google Patents

Abstract

PURPOSE:To simply and easily connect chip-type electronic parts with wiring patterns, by forming contact holes at thin film parts in a resinous substrate and then forming wiring patterns which are connected with terminal electrodes of chip-type electronic parts through the contact holes on the surface of the resinous substrate. CONSTITUTION:Contact holes 4a... are formed by an etching process on thin films 4, which are parts included in a resinous substrate 1, and at the positions corresponding to electrode pads on a semiconductor chip 2 and electrode terminals 3a on a capacitor chip 3. Wiring patterns 5... are formed on the upper surface of the resinous substrate 1 by the etching resinous substrate 1. Partial wiring patterns are directly connected with respectively the electrode pads on the semiconductor chip 2 and the electrode terminals 3a on the capacitor chip 3. Hence, the chip-type electronic parts can be simply and easily connected with the wiring patterns without requiring a large-scale bonding apparatus.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] This %Ijl relates to an electronic component mounting structure and its mounting method.

[Conventional technology and common points] Conventionally, Chip J! ! Electronic component 1 For example, a method for connecting a semiconductor chip to a wiring board is to connect thin metal wires of gold, copper, aluminum, etc. to electrode pads formed on the surface of the semiconductor chip. a Wire bonding method, in which the wire is stretched between the electrode terminals of the substrate and connected by thermocompression bonding or ultrasonic rock, or the like.

There is a wireless bonding method in which a wiring pattern is formed in advance on a wiring board in correspondence with the electrode pads of a semiconductor chip, semiconductor chips are placed on this wiring pattern, and bonding is performed all at once.

However, in any of the above-mentioned methods, a large-scale bonding device is required, and there is a problem in that the connection work cannot be easily performed. Moreover, in such a method, the size of the electrode pad of the semiconductor chip must be larger than a certain area (approximately 501 Lm square) in order to ensure mechanical precision during bonding and mechanical strength of bonding. There are disadvantages such as an increase in the area of the semiconductor chip or a limitation on the number of lead-out electrodes.

[Objective of the Invention] This invention was made in consideration of the above circumstances, and its purpose is to easily and easily connect chip-type electronic components and wiring patterns without requiring a large-scale bonding device. It is an object of the present invention to provide a mounting structure for electronic components that can be connected to the electronic components and has high electrical reliability, and a method for mounting the same.

[Summary of the Invention] In order to achieve the above object, the present invention embeds a chip-type electronic component in a resin substrate with its terminal electrode forming surface close to the surface of the resin substrate, and then embeds the electronic component in the resin substrate. A contact hole is formed in a thin film portion of the resin substrate that covers the terminal electrode portion of the component, and a wiring pattern is formed on the surface of the resin substrate to be connected to the terminal electrode of the electronic component via the contact hole. It is something.

[Embodiment 1] Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 and 2.

Figure 1 shows the mounting structure of a chip-type electronic component.

In the figure, 1 is a resin substrate. This resin substrate l is a sheet-like material made of an insulating thermoplastic resin such as polyethylene terephthalate (hereinafter abbreviated as PET), and inside it is an LSI? A semiconductor chip 2 and a capacitor chip 3 are embedded with a thin film layer 4 remaining. This tJ film layer 4 is a part of the resin substrate 1, has a thickness of 51 Lm or less, preferably about 2 Bm, and is used for the electrode pads of the semiconductor chip 2 and the electrode terminals of the capacitor chip 3.
Contact holes 4a, e, and 4a are provided at locations corresponding to a and 3a.
is formed by etching. Furthermore, a wiring pattern 5.Φ. is formed on the upper surface of the resin substrate 1. The wiring patterns 5-- are formed by etching a conductive thin film formed on the resin substrate 1, and a part of the wiring patterns 5-- are formed by etching the conductive thin film formed on the resin substrate 1, and a part thereof is connected to the electrode pads of the semiconductor chip 2 and the electrode pads of the semiconductor chip 2 through the contact holes 4a--. It is directly connected to the electrode terminals 3a, 3a of the capacitor chip 3.

Next, the manufacturing method will be explained with reference to FIG.

First, as shown in FIG. 2(a), the thermoplastic film 7 is placed on the support base 6. In this case, the support stand 6 is
JII, and is designed to cool the plastic film 7. The thermoplastic film 7 is made of an insulating resin such as PET and softens when heated, and the semiconductor chip 2 and the capacitor chip 3 are placed on the top surface of the thermoplastic film 7.

In this state, semiconductor chip 2 and capacitor chip 3
When applying pressure while heating, each chip 2.3 is embedded in the thermoplastic film 7, as shown in FIG. 2(b). In this case, the support base 6 is set at a temperature considerably lower than the softening point of the thermoplastic film 7, for example, 0°C.
The heating temperature of the chip 2.3 is significantly higher than the softening point of the thermoplastic film 7. This is to improve the thermal adhesion of the thermoplastic film 7 to each chip 2.3. For example, for PET whose softening point is 67°C, the heating temperature is set to
The temperature should be around 50℃. Then, each chip 2.3 is heated and press-fitted until the thickness of the thermoplastic film 7 becomes the thin film layer 4 of 2 pm. In this case, it is not necessarily necessary to press-fit until the thin film layer 4 of 2 ILm is formed. Even if the thickness is 5 pm or more, the FM film layer can be etched uniformly over the entire surface in plasma of 1 m element and fluorine after implantation. 4 to 2
It may be about #Lm.

Each chip like this? , 3 after embedding Figure 2 (
As shown in C), an insulating material 8 such as epoxy resin is applied to the back surface (upper surface) to make it a flat surface. As a result, the resin substrate 1 is formed, and the chips 2 and 3 are embedded in this resin substrate l. In this case, the back side (top side) of each chip 2.3 is covered and protected by the insulating material 8,
The front side (lower side) is protected by a thin film layer 4.

Thereafter, as shown in FIG. 2(d), the resin substrate 1 is turned upside down so that the thin film layer 4 side faces the upper surface side, and contact holes 4a are formed in the thin film layer 4 by plasma etching. That is, a photoresist film 21. The photoresist 1111 was applied to a thickness of about m, and the photoresist 1111 was removed at predetermined locations (that is, the locations corresponding to the electrode pads and electrode terminals 3a and 3a of each chip 2 and 3) using a photo phosphorography method. Thereafter, the thin film layer 4 is etched in a mixed plasma of oxygen and fluorine to form contact holes 4a. In this case, the photoresist film is also etched in the plasma in the same way as the thin film layer 4 of the resin substrate 1, so the step of peeling off the photoresist film is not necessary. When the contact holes 4a are formed in this way, the electrode pads and electrode terminals 3a, 3a of each chip 2.3 are sprayed out.

Thereafter, as shown in FIG. 2(e), a conductive thin film 9 is formed on the surface (upper surface) of the resin substrate 1. This thin film 9 is a thin film made of metal such as aluminum, and is deposited to a thickness of about 2 m on the surface of the resin substrate 1 by DC sputtering. Moreover, a part of the thin film 9 is located in the contact hole 4a of the thin film layer 4.
. . , and directly contacts the electrode pads and electrode terminals 3a, 3FL of each chip 2, 3 for conduction.

After this, as shown in FIG. 2(f), the photo
The conductive portion [9 is etched by phosphorography to form a predetermined wiring pattern 5. At this time, not only the patterns for guiding the electrode pads and electrode terminals 3a, 3a of each chip 2.3 to the outside, but also all wiring patterns are formed on the resin substrate l. As shown in FIG. 2(g), a protective film 10 made of epoxy resin or the like is coated on the resin substrate 1 on which the wiring pattern 5 is formed in this manner to protect the entire surface.

Therefore, according to the electronic component mounting structure and mounting method described above, it is possible to simply and easily connect a chip-type electronic component and a wiring pattern without the need for a large-scale bonding device, and also to ensure continuity. You can get something highly reliable. In this case, in particular, the surface of the resin substrate l on the side of the thin film layer 4 is formed into a uniform plane, and the wiring pattern 5 is formed on the conductive S film 9 formed on this plane by photolithography. So,
Even if the electrode pads of the semiconductor chip 2 are about 17 mm square, they can be sufficiently guided to the outside, making it possible not only to achieve high-density wiring, but also to reduce the size of the semiconductor chip 2 and increase the density of its electrodes. I can do it.

Note that the present invention is not limited to the above-described embodiment, and for example, each chip 2.3 may be embedded as shown in FIG. 3 (a). , a thin film layer 11 made of a heat-resistant resin such as polyimide is provided on the lower surface of the thermoplastic film 7 in advance. Then, each of the chips 2 and 3 is placed a on the upper surface of the thermoplastic film 7. Thereafter, each of the chips 2 and 3 is press-fitted into the thermoplastic film 7 without being heated, as in the embodiment described above. In this case, the support stand 6 can also be used as a heating means.

Press-fit each chip 2, 3 so that the thermoplastic film 7 does not remain, and bring the bottom surface of each chip into close contact with the thin film N11.Next, as shown in FIG. 3(C), the thermoplastic film An insulating material 8 such as epoxy resin is applied to the upper surface of each chip 2.3 to cover and protect the back surface side (upper surface side) of each chip 2.3. After this, contact holes and wiring patterns can be formed in exactly the same manner as in the above-mentioned embodiment. By doing this, it is not necessary to adjust the amount of embedding of each chip 2.3 as in the above-mentioned embodiment. Therefore, each chip 2.3 can be embedded more easily and better. In addition, when the resin substrate is composed of a two-layer film as in the embodiment explained in FIG. 3, each chip 2.3 is placed on the base film (corresponding to the thermoplastic film 7 in FIG. A fitting hole may be formed, a thin film made of polyimide or the like (corresponding to the thin film layer 11 in FIG. 3) may be provided on the underside of the hole, and each chip 2.3 may be placed in each hole. In this way, the embedding work can be performed even more easily.

Furthermore, in the embodiments shown in FIGS. 2 and 3, if the electronic component to be embedded is a semiconductor chip, the back surface of the semiconductor chip is etched after the semiconductor chip is press-fitted, as shown in FIG. 4(a) (
As shown in FIGS. 2(b) and 3(b), after press-fitting the semiconductor chip 2 into the thermoplastic film 7,
Wet etching with a mixture of hydrofluoric acid, nitric acid, and sulfuric acid,
Alternatively, the back surface of the semiconductor chip 2 is etched by any etching method such as dry etching using fluorine plasma,
As shown in FIG. 4(b), the thickness of the semiconductor chip 2 is 15 mm.
The thickness should be approximately 0 μm. Thereafter, as shown in FIG. 4(C), a thermoplastic resin, preferably the same resin as the thermoplastic film 7, is potted into the recesses of the thermoplastic film 7 created by etching the semiconductor chip 2, and sealed. Then, the back surface of the thermoplastic film 7 is polished or reflowed to make it flat as shown in FIG. 4(d). According to this method, the thickness of the wafer is 30 mm at the scribing stage.
A semiconductor chip having a thickness of 0 gm or more can be made thinner to 150 gm or less.

[Effects of the Invention] As explained above, in the present invention, after a chip-type electronic component is embedded in a resin substrate with its terminal electrode forming surface being brought close to the surface of the resin substrate, the terminal electrode of this electronic component is embedded. A contact hole is formed in the thin film part of the resin substrate that covers the electronic component, and a wiring pattern is formed on the surface of the resin substrate to be connected to the terminal electrode of the electronic component through the contact hole. A chip-type electronic component and a wiring pattern can be connected simply and easily without the need for a bonding device, and a product with high electrical reliability can be obtained.

[Brief explanation of drawings]

FIG. 1 and FIG. 2 show one embodiment of the present invention.
The figure is an enlarged sectional view of the main part showing the mounting structure of electronic components, Figures 2 (a) to (g) are process diagrams showing the mounting method, and Figure 3 (
a) to (c) are main part process diagrams of the modified example, and Fig. 4 (a) to (
c) is a main part process diagram of a different modification. l...resin substrate, 2... semiconductor chip, 3
・Old...Capacitor chip, 3a...Electrode terminal, 4.11...l8Ji film layer, 5...
Wiring pattern, 7. Old... Thermoplastic film, 8...
... Insulating material, 9... Conductive thin film. Figure 4: Historical form 4 taku/1 zero shu x hand! Figure 2 Missing page, TT-Procedure amendment (method) April 24, 1985 Patent application No. 298982, filed in 1985 2 Title of invention Electronic component mounting structure and its mounting method 3 , Relationship with the person making the amendment Patent applicant address 2-6-1 Nishi-Shinjuku, Shinjuku-ku, Tokyo Name (14
4) Tadashi Kashio, Representative of Casio Computer Co., Ltd.
Yu 4, Agent Address: 3rd Floor, T-S Building, 13-4, Nishishintachibana 1-T, Minato-ku, Tokyo ~\ Name: Patent Attorney (7734) Town 1) Shun Kaji; -5, Date of Amendment Order: 1988 March 250 (shipping port) 6. Subject of amendment (1) "Brief explanation of drawings" column of the specification. 7. Contents of amendment (1) In page 13, line 11 of the specification, “Figure 4 (a) to (
C)" should be corrected to "Fig. 4 (a) to (d)."

Claims (2)

[Claims] (1) In an electronic component mounting structure in which a chip-type electronic component is mounted on a wiring board, the wiring board is composed of a resin substrate and a wiring pattern formed on the surface of the resin substrate, and the electronic component is The terminal electrode is embedded in a resin substrate with its terminal electrode forming surface close to the wiring pattern forming surface, and the terminal electrode is directly connected to the wiring pattern through a contact hole formed in a thin film portion of the resin substrate above the electrode. An electronic component mounting structure characterized by: (2) In an electronic component mounting method in which a chip-type electronic component is mounted on a wiring board, the electronic component is placed in a resin substrate that serves as the base of the wiring board, and the terminal electrode forming surface thereof is placed on the surface of the resin substrate. a step of embedding the electronic component in close proximity; a step of forming a contact hole in a thin film portion of the resin substrate that covers the terminal electrode portion of the electronic component; and a step of connecting to the terminal of the electronic component through the contact hole on the surface of the resin substrate. A method for mounting an electronic component, comprising the step of forming a wiring pattern.