JPS5824012B2 - Manufacturing method of mounting body - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a packaged body, and relates to a method for electrically leading out an electrode terminal formed on an element such as an IC or LSI to an electrode terminal of an external circuit. was developed, but the most known method is the A
There is a so-called wire bonding technique in which the electrode terminals are connected to each other by thermocompression bonding or ultrasonic bonding using ultrafine wires such as U and A1.

In this method, the reliability of the connection is high when the number of electrode terminals is small, but as the number of functions in one element increases as in recent LSIs, the number of electrode terminals increases to 40 to 70 terminals. In this case, since bonding is required twice to make this connection, the number of connections becomes extremely large.

That is, if the element has 70 electrode terminals, the number of connections reaches 140.

This lowers the reliability of the connection and makes it difficult to reduce the cost of this connection process.

Also, when connecting to external circuits, the above-mentioned IC, LSI
The device must be fixed to the circuit board, and when it is connected using ultra-fine wires, the ultra-fine wires are lifted up in a curved manner from the surface of the device, making it extremely difficult to create a thinner and more compact package. Ta.

In order to eliminate such drawbacks, a so-called wireless technology that does not use ultra-fine wires has been put into practical use, which processes, for example, 70 electrode terminals at once.

For example, in the beam lead method in this wireless technology, a rectangular electrode lead is formed on the electrode terminal of the element at the stage of processing a silicon wafer.

However, in the beam lead method, elements cannot be formed on the silicon surface where electrode leads extending from electrode terminals are formed.

Therefore, the effective area in which elements are formed within one wafer is 55% compared to when elements are formed completely within the entire wafer.
0 to 60 inches, resulting in extremely poor wafer utilization efficiency.

That is, since the lead length is usually 0.7 to 1.2 mm, the silicon area around this length around one element exists solely for lead formation, and therefore requires expensive silicon. Not only is the wafer wasted, but the manufacturing process for forming electrode leads is complicated, which makes it more expensive, and although thinner and more compact devices can be achieved, it has been difficult to achieve lower costs.

In addition, in the film carrier method, metal protrusions (usually called bumps) are placed on the electrode terminals of the device during the wafer process stage.
The connection is made by applying pressure and heating to the Sn-plated Cu foil lead formed on the polyimide film on the metal protrusion to form an Au-8n eutectic. In this method, since the metal protrusion and the lead must be connected, the number of connection points is the same as in the wire punching method, which increases the number of man-hours.

The present invention provides a method for solving the above-mentioned disadvantages by forming lead electrodes by plating on elements such as ICs and LSIs, which have electrode terminals for external connection formed on their surfaces. .

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, a continuous resin film 1 made of polyimide, polyester, etc. is provided with first openings 2, and
A first metal film 3 of Cu, A1, etc. having a thickness of 100 μm is attached to the resin film 1 with an adhesive or the like.

Next, the first metal film 3 is provided with an electrode terminal 5 of the element 4, which will be described later.
A second aperture 6 is formed in the vicinity.

This second opening 6 may be a long hole so as to span the electrode terminals 5 of the elements 4 in the column direction, as shown in FIG. 2a, or
Alternatively, it may be a circular hole corresponding to the electrode terminal 5 of the element as shown in FIG.

The element 4 shown in FIG. 3 is an electronic circuit element such as an IC or LSI, and is divided by a dicing saw.
Resin 7 is applied.

The resin 7 is at least a thermosetting resin having adhesive properties, and may be, for example, a photosensitive resin.

When the coating is completed, the openings 6 of the first metal film 3 and the electrode terminals 5 of the element 4 are aligned, thermocompressed, and cured and fixed (FIG. 3a).

Next, using the first metal film 3 as a mask, the resin 7 exposed in the second opening 6 is opened by plasma treatment or sputtering to expose the electrode terminal 5 of the element 4 (Fig. 3). b).

Thereafter, a second metal film 8 consisting of multiple layers is deposited on the first metal film 3, including the electrode terminal 5 of the exposed portion 6', by vacuum evaporation (FIG. 3C).

The second metal film 8 consisting of multiple layers is Cr-CuyCr-
Cu-Au, Cr-Ni, Cr-Ag, CrAu,
A combination of Ti CuyT i -A u, etc.,
The Cr, Ti film is in direct contact with the element or the first metal film surface,
A material for increasing adhesive strength, including Cu, Ag, and Au.
, Ni is a material for increasing conductivity.

Cr, Ti film: 500-2000 people, Cu, Ag
, Au, and Ni have a thickness of 3000 to 20000λ.

Next, a photosensitive resin film 9 is placed on the second metal film 8 consisting of multiple layers.
A rectangular pattern 9' including the opening 6' of the metal film 3 near the electrode terminal 5 of the element 4 and extending to the resin film 1 is formed by photoetching (FIG. 3d). .

After this, using the metal film 3 or the second metal film 8 made of multiple layers as one electrode, Au, Ag, etc.
, Cu, or the like is formed by plating.

After that, the photosensitive resin 9, the first metal film 3, and the second
If the metal film 8 consisting of multiple layers is removed by etching, the third
Obtain the state shown in Figure e.

FIG. 4 is a perspective view of FIG. 3e.

The element 4 has a second multilayer metal film 8 on the electrode terminal 5.
A metal film 10 formed by plating is provided through the
The metal film 10 becomes an electrode lead.

Further, the other end of the metal film 10 as the electrode lead is fixed onto the resin film 1 via the first metal film 1 and the second metal film 8 consisting of multiple layers.

As described above, in the present invention, electrode leads for external connection can be easily and accurately formed on the electrode terminals 5 of the element 4 by plating.

When mounting the element in the state shown in Fig. 3 e1 on another circuit board, it is sufficient to cut the electrode lead 10 from the part A, remove the element 4 from the resin film 1, and connect the lead 10 to the other board. .

Furthermore, in the manufacturing method of the present invention, the resin film 1 is not consumed because it is simply a material for conveyance.

Therefore, after the element is removed, it can be recycled and used any number of times.

Furthermore, since the elements 4 can be used by selecting only electrically good products, manufacturing yield can be significantly improved and costs can be reduced.

The above method provides the following effects.

■ As mentioned above, the film carrier method is highly suitable for mass production because the element chips are handled by tape transport, but it requires a bonding process (usually called ILB) to connect the electrode leads formed on the wafer. shall be.

This bonding process heats (400-500°C)
), the AA electrode terminal is deformed due to the pressure (30-60 g/pad) applied on the bump and the electrode of the device, and cracks occur in the CVD S t 02 film covering part of the Al electrode terminal.

Since the Al electrode terminal is exposed due to this crack, the corrosive solution of the Al electrode terminal enters from this part and dissolves the Al electrode terminal, reducing the strength of the bump and increasing the contact resistance between the bumps. , which caused a decrease in reliability.

However, in forming electrode leads by the manufacturing method of the present invention, the leads are formed by a plating method (
(This is formed using the same method as bump formation using the film carrier method), unlike the film carrier method, there is no need for an ILB process, and there is no cracking of CVD5102, reducing man-hours and increasing reliability. I can do things.

Furthermore, in the film carrier method, bumps are formed on the electrode terminals of all chips, including defective chips, because the plating process is performed on the wafer.

For this reason, bumps formed on defective chips (e.g. Au
bump) is a complete waste.

However, in the present invention, only good chips can be selected in advance and electrode leads can be formed only on good chips.
Waste of materials can be eliminated and manufacturing costs can be reduced.

■ Also, in the beam lead method, it is necessary to occupy the wafer area by the amount of the beam lead, so the yield of chips per wafer deteriorates significantly, and since beam leads are also formed for defective chips, This wastes material and increases manufacturing costs.

However, in the manufacturing method of the present invention, there is no additional loss of wafer area, and since only good chips can be selected and input into the manufacturing process, manufacturing costs can be reduced.

Furthermore, since the chips on which the electrode leads are formed are placed continuously on the film tape, the chips are easy to handle and can be easily mass-produced.

Next, a method according to another embodiment of the present invention will be described.

Fig. 5 Resin film 1 made of polyester, polyimide, etc.
1 is provided with an opening 12, and a first photosensitive resin 13 is pasted onto the resin film 11.

The first photosensitive resin 13 is a film-like photosensitive resin.
Although pressure bonding may be used as shown in the figure, it is possible to uniformly form the resin film 11 on the resin film 11 using a roller coating device.

Next, an element 14 such as an IC or an LSI shown in FIG. 6 is placed in the center of the opening 12 of the resin film 11 and fixed by pressure on the surface of the first photosensitive resin 13.

Thereafter, openings 15 and 16 are formed in the vicinity of the electrode element of the element 14 and a part of the resin film by photolithography (sixth hole).
Diagram a).

The first photosensitive resin 13 on the resin film 11 is formed so as to be located at both ends of the resin film 11.

The first photosensitive resin is heat-treated at a temperature of 120 to 180° C. in the state shown in FIG. 6a, and is thermally cured.

Next, a metal film 17 consisting of multiple layers is deposited over the entire surface of the first photosensitive resin 13 including the surface of the element 14 by vacuum evaporation (FIG. 6b).

The metal film 17 is made of Cr-Cu, Cr-Cu-Au, Cr-
Ni, Cr-Ag.

A combination of Cr-Au, Ti-Cu, T1-Au, etc., where the Cr and Ti films are in direct contact with the element surface and are materials for obtaining adhesion strength with the element surface, and Cu
, Ag, Au.

Ni is a material for increasing conductivity.

A second photosensitive resin film 18 is formed on the metal film 17 consisting of multiple layers.
Apply.

The second photosensitive resin 18 may be pasted onto the metal film 18 using a roller coating device.
It may be applied on top.

Next, a rectangular pattern 19 that includes the openings 15 (near the electrode terminals of the element 14) in the first photosensitive resin and reaches the resin film 11 is formed.

This is shown in Figure 6C.

Thereafter, a surface of a rectangular pattern 19 on which the metal film 17 of a rectangular pattern 19 is formed by plating with the second photosensitive resin 18 using the metal film 17 consisting of multiple layers as one plating electrode is coated with a metal layer of Au, Ag, Cu, etc. Form 20.

After the plating process is completed, the first and second photosensitive resins are removed, and a portion of the exposed metal film 17 consisting of multiple layers is removed to obtain the shape shown in FIG. 6d.

In FIG. 6d, an electrode lead (metal layer) 20 is formed on the electrode terminal of the element 14 by plating with a metal film 17 interposed therebetween.
The electrode lead 20 has a structure in which it is in contact with a resin film 14 via a metal film 17.

That is, the element 14 is fixed to the opening 12 of the resin film 11 via the electrode lead 20.

FIG. 7 shows the appearance of the state shown in FIG. 6d.

In this way, the method shown in FIG. 6 can also provide a packaged electronic circuit element in the same manner as in the above-mentioned embodiments.

In addition, in Fig. 6, if you cut from position B of d,
The film 11 and the element 14 can be separated.

Also in the manufacturing method shown in FIG. 6, the resin film 2
Since there is no damage until the final process, it can be recycled and reused many times.

The method shown in FIG. 6 can also achieve the same effect as the method shown in FIG. 3.

As described above, the present invention eliminates the drawbacks of the conventional beam lead and film carrier methods, and provides a unique manufacturing method, which enables a thinner and smaller lead terminal to be produced at low cost and with high reliability. This makes it possible to obtain a packaged body for electronic circuit elements such as semiconductor devices, which greatly contributes to high-density packaging.

[Brief explanation of drawings]

Figure 1 is a perspective view of an example of the resin film and metal film used in the present invention, Figures 2a and 1) are perspective views of the metal film on the film with holes opened, and Figures 3 a-e are the invention. FIG. 4 is a perspective view of FIG. 3e, FIG. 5 is a perspective view of the resin film and photosensitive resin used in the present invention, and FIGS. FIG. 7 is a cross-sectional view of the manufacturing process of a package according to another embodiment of the present invention, and FIG. 7 is a perspective view of FIG. 6d. 1.11...Resin film, 2, 6.6', 1
2...Opening part, 3,17...Metal film,
4, 14... element, 7, 9, 13, 18...
...Photosensitive resin, 9'. 19...hole pattern, 10,20...
- Electrode IJ-do.

Claims (1)

[Claims] 1. A step of pasting a first metal film on an insulating film having a first opening, and opening a region of the first metal film near an electrode terminal of an element. a step of forming a second aperture, a step of applying an adhesive film to the surface of the element, and a step of aligning the second aperture of the first metal film and an electrode terminal of the element. a step of fixing the element to the first metal film with the adhesive film by pressure bonding, and a step of removing the adhesive film exposed from the second opening of the first metal film. a step of depositing a second metal film on the first metal film; and a step of applying a resin film on the second metal film, and covering the area of the resin film in the vicinity of the electrode terminal of the element, including the insulation film. A hole is made in the area that reaches the surface of the film using a photoetching method,
forming a third opening; and plating the second metal film exposed in the third opening using the first metal film or the second metal film as one electrode. a step of forming a third metal film; and a step of removing the resin film and the first and second metal films; 1. A method for manufacturing a mounting body, comprising: forming a mounting body. 2. A step of pasting a first resin film on an insulating film having a first opening, a step of fixing an element to a first development part of the film, and a step of attaching a first resin film to an insulating film having a first opening, and a step of fixing an element to a first developed part of the film, and a step of attaching a first resin film to an insulating film having a first opening, and a step of fixing an element to a first developed part of the film, and a step of attaching a first resin film to an insulating film having a first opening. forming a second opening in a part of the upper resin film; depositing a metal film on the film;
A second resin is applied onto the metal film, and a second resin is applied onto the film, including a second opening near the electrode terminal of the element.
a step of forming holes in the region of the resin using the metal film as one electrode, a step of forming a metal layer in the region of the hole with a second resin by plating, and removing the exposed metal film, and forming an electrode lead made of the metal layer on the electrode terminal of the element.