JP2001274193A - Semiconductor device and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable an anisotropic conductive adhesive agent interposed between a semiconductor device and a board to be controlled in fluidity induced, when the semiconductor device and the board undergo thermocompression treatment to ensure the necessary number of the conductive particles 31a of the anisotropic conductive adhesive agent 31 trapped between the protrudent electrode of a semiconductor device and the board electrode 23 of the board 22, by which a fine connection of low in resistance and high reliability can be provided. SOLUTION: A semiconductor device is equipped with a protective film 13 having an opening located above a connection electrode pad 12, a fluidity control film 15 provided on the protective film 13 other than a connection region on the periphery of the semiconductor device 10, a common electrode film 15 provided on the connection electrode pad 12, and a protrudent electrode 17 provided on the common electrode film 14. A method of manufacturing the same is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a semiconductor device connected to a circuit board using an anisotropic conductive adhesive and a method for manufacturing the same.

[0002]

2. Description of the Related Art Bare chip mounting, in which a semiconductor device is directly connected to a substrate, is an ideal mounting method for electronic equipment that is becoming smaller year by year.

An example of a mounting method for connecting a semiconductor device having a straight wall-shaped projection electrode and a liquid crystal display device with an anisotropic conductive adhesive will be described with reference to the drawings. 9 to 11 are sectional views showing the structure of the semiconductor device, and FIG.
FIG. 3 is a cross-sectional view illustrating a mounting structure in which a semiconductor device and a circuit board are connected.

[Description of mounting structure of semiconductor device and circuit board:
[FIG. 12] As shown in FIG. 12, in a semiconductor device 10, connection electrode pads 12 provided on an element formation surface of a silicon substrate 11 are arranged. The protective film 13 is provided so that the connection electrode pad 12 of the semiconductor device 10 is opened.

The common electrode film 14 is formed on the connection electrode pad 12.
Then, a protruding electrode 17 is formed on the common electrode film 14.

Further, the bump electrode 1 of the semiconductor device 10
7 and the substrate electrode 23 of the substrate 22 are anisotropic conductive adhesive 31
Are connected by conductive particles 31a.

[Description of Method of Manufacturing Semiconductor Device: FIGS. 9 to 12] Next, a method of manufacturing a semiconductor device will be described. As shown in FIG. 9, in the semiconductor device 10, a connection electrode pad 12 made of aluminum is formed to a thickness of 1 μm on the element formation surface of a silicon substrate 11.

[0010] As shown in FIG.
A protective film 13 for protecting a semiconductor element is formed on the entire surface of the semiconductor device 10 including. The protective film 13 is generally made of an inorganic film such as a silicon oxide film or a silicon nitride film containing phosphorus, and has a thickness of 1 μm.

Then, the protective film 1 is exposed by photolithography and etching so that the connection electrode pad 12 is exposed.
3 is opened.

The common electrode film 14 is formed on the entire surface of the semiconductor device 10 by aluminum of 1 μm, chromium of 0.01 μm, and copper of 1 μm.
A metal multilayer film having a thickness of μm is sequentially formed by a method such as a sputtering method or a vacuum evaporation method.

Next, a plating resist 16 made of a thick liquid photosensitive resist is coated on the entire surface of the semiconductor device 10 to a thickness of 20 mm.
μm is formed. Thereafter, an opening is provided in the plating resist 16 in the portion of the common electrode film 14 on the connection electrode pad 12 by photolithography.

Further, a protruding electrode 17 made of gold is formed to a thickness of 15 μm by electrolytic plating.

As shown in FIG. 11, the unnecessary plating resist 16 is removed. Further, the common electrode film 14 other than the base of the protruding electrode 17 is removed.

[Explanation of Method of Connecting Semiconductor Device to Substrate of Liquid Crystal Display Device: FIG. 12] Next, a method of connecting the semiconductor device to the substrate of the liquid crystal display device will be described. As shown in FIG.
Indium tin oxide serving as a substrate electrode 23 is formed to a thickness of 0.2 μm on a substrate 22 made of glass. Thereafter, patterning is performed by photolithography so as to correspond to the protruding electrodes 17 of the semiconductor device 10.

An anisotropic conductive adhesive 31 is disposed on a substrate 22. The anisotropic conductive adhesive 31 is obtained by mixing conductive particles 31a with an insulating resin made of an epoxy resin, and is a sheet having a thickness of 25 μm. The conductive particles 31a have a particle size of 5 μm, in which two layers of nickel and gold are plated on the surface of plastic beads.

Next, after the protruding electrodes 17 of the semiconductor device 10 are aligned with the substrate electrodes 23 of the substrate 22, a heating and pressurizing process is performed to cure the anisotropic conductive adhesive 31.

The heating and pressing conditions are as follows: a temperature of 170 ° C. to 200 ° C.
C., pressure is 400 Kg / cm ² .

When the anisotropic conductive adhesive 31 is heated and pressurized, the anisotropic conductive adhesive 31 flows, and the anisotropic conductive adhesive 31 flows between the protruding electrode 17 of the semiconductor device 10 and the substrate electrode 23 of the substrate 22. Electrical connection is obtained through the conductive particles 31a of the agent 31.

[0019]

In the prior art described above, the gap between the semiconductor device 10 and the substrate 22, that is, the protective film 13 is hardened by heating and pressing to cure the anisotropic conductive adhesive 31. The distance between the surface and the surface of the substrate 22 is determined by the height of the protruding electrode 17 and the outer shape of the conductive particles 31a of the anisotropic conductive adhesive 31, and is about 20 μm.

Since the thickness of the anisotropic conductive adhesive 31 before the heating and pressurizing treatment is 25 μm, the anisotropic conductive adhesive 31 corresponding to the thickness of 5 μm and the projection electrode 17 is applied to the semiconductor device 10.
Flows out of the gap between the substrate and the substrate 22.

The flow of the anisotropic conductive adhesive 31 affects the number of conductive particles 31 a of the anisotropic conductive adhesive 31 captured between the protruding electrode 17 of the semiconductor device 10 and the substrate electrode 23 of the substrate 22. give.

When the flow of the anisotropic conductive adhesive 31 is fast, the number of the conductive particles 31a of the anisotropic conductive adhesive 31 to be captured decreases.

As shown in FIG. 8, since the protruding electrodes 17 are arranged on two long sides of the semiconductor device 10, the flow of the anisotropic conductive adhesive 31 is hindered by the 10, the flow becomes faster in the short side direction.

A large number of the protruding electrodes 17 on the long side of the semiconductor device 10 form an anisotropic conductive adhesive 31 that is trapped between the protruding electrode 17 of the semiconductor device 10 and the substrate electrode 23 of the substrate 22 depending on the arrangement position. The number of the conductive particles 31a of the semiconductor device 10 fluctuates, and the terminal of the portion near the short side of the semiconductor device 10 has the anisotropic conductive adhesive 31 trapped between the protruding electrode 15 of the semiconductor device 10 and the substrate electrode 23 of the substrate 22. Conductive particles 31a
Is extremely reduced to less than half.

When the connection resistance value of 1Ω or less is required, 1
Conductive particles 3 of ten anisotropic conductive adhesives 31 per terminal
Since 1a is required, the connection area of the terminal near the short side of the semiconductor device 10 must be twice or more.

For this reason, it is very difficult with the conventional technology to realize fine connection, which is mounting with a small connection area, with low resistance and high reliability.

As a method for suppressing the flow of the anisotropic conductive adhesive 31, the anisotropic conductive adhesive 31 before the heating and pressing treatment is performed.
The thickness of the semiconductor device 10 and the substrate 22
It can be considered to be μm.

However, it is possible to suppress the flow of the anisotropic conductive adhesive 31 by this means, but the air bubbles are trapped between the semiconductor device 10 and the substrate 22 so that the anisotropic conductive adhesive 31 is cured. .

These bubbles adversely affect the reliability test. In the temperature cycle test, strain concentrates on the terminal closest to the bubble and induces a failure. In addition, it causes defects such as peeling of the anisotropic conductive adhesive in a high temperature test and water absorption in a moisture resistance test.

For this reason, it is common to mount the semiconductor device 10 using a 25 μm anisotropic conductive adhesive 31 which is slightly thicker than the gap between the semiconductor device 10 and the substrate 22.

[Object of the Invention] An object of the present invention is to solve the above-mentioned problems and to control the flow of an anisotropic conductive adhesive generated at the time of pressurizing and heating connection between a semiconductor device and a substrate to thereby form a projection electrode of a semiconductor device. A semiconductor device capable of ensuring the number of conductive particles of an anisotropic conductive adhesive to be captured between a substrate and a substrate of a substrate, thereby providing a low-resistance and highly reliable fine connection and a method of manufacturing the same. It is an object of the present invention to provide.

[0032]

In order to solve the above-mentioned problems, the following means are employed in a semiconductor device and a method of manufacturing the same according to the present invention.

In the semiconductor device of the present invention, a protection film having an opening on the connection electrode pad, a flow control film provided on the protection film in a portion other than the connection region on the outer periphery of the semiconductor device, and a connection electrode pad A semiconductor device having a common electrode film provided on the common electrode film and a projecting electrode provided on the common electrode film.

In the method of manufacturing a semiconductor device according to the present invention, a step of forming a protective film on a semiconductor device having connection electrode pads and patterning the protective film so that the connection electrode pads are opened; Forming a flow control film on an outer peripheral portion of the semiconductor device in a portion other than a connection region, forming a common electrode film on the semiconductor device, and forming a plating resist on the semiconductor device. Forming a plating resist, patterning the plating resist so that the protruding electrode formation region is opened, forming a protruding electrode by plating the plating resist opening, removing the plating resist, Removing the common electrode film other than at the base.

[Operation] In the mounting structure of the semiconductor device according to the present invention, the flow of the anisotropic conductive adhesive is controlled by the flow control film disposed on the short side of the semiconductor device so that the same position is applied to any terminal of the semiconductor device. It was made to flow.

In any of the terminals of the semiconductor device, the conductive particles of the anisotropic conductive adhesive captured between the protruding electrode of the conductor device and the substrate can be sufficiently ensured uniformly.

As a result, in the present invention, the connection area can be minimized, and a low-resistance and highly reliable fine connection can be provided.

[0038]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The mounting structure of a semiconductor device according to the best mode for carrying out the present invention will be described below with reference to the drawings, taking the mounting of a semiconductor device and a liquid crystal display device as an example.

FIGS. 1 to 6 are sectional views showing the structure and manufacturing method of the semiconductor device of the present invention, and FIGS. 2 and 7 are plan views showing the structure and manufacturing method of the semiconductor device of the present invention.

[Description of Mounting Structure of Semiconductor Device: FIG. 1] The structure of the semiconductor device according to the embodiment of the present invention and the mounting structure of the semiconductor device and the liquid crystal display device will be described.

As shown in FIG. 1, the protruding electrode 17 of the semiconductor device 10 and the substrate electrode 23 of the substrate 22 are connected by conductive particles 31 a of an anisotropic conductive adhesive 31.

In the semiconductor device 10, connection electrode pads 12 provided on an element formation surface of a silicon substrate 11 are arranged. The protective film 13 is provided so that the connection electrode pad 12 of the semiconductor device 10 is opened. The flow control film 15 is provided on the protective film 13 in a portion other than the connection region on the outer peripheral portion of the semiconductor device 10. The common electrode film 14 is formed on the connection electrode pad 12, and the protruding electrodes 17 are formed on the common electrode film 14.

[Structural Description of Semiconductor Device: FIGS. 1 to 3]
Next, the structure of the semiconductor device will be described. As shown in FIG. 3, the semiconductor device 10 has a connection electrode pad 12 provided on the element formation surface of a silicon substrate 11.

As shown in FIG. 2, the connection electrode pad 12 has an input signal terminal for connecting an external signal and an output signal terminal for connecting to a display element of a liquid crystal display device. Due to the problem of the resistance value of the routing wiring of the liquid crystal display device, it is general to lay out using two long sides of the semiconductor device. The protective film 13 is provided so that the connection electrode pad 12 of the semiconductor device 11 is opened.

The flow control film 15 made of an organic material such as a photosensitive polyimide is disposed on the protective film 13 on the outer periphery of two short sides of the semiconductor device 10.

As shown in FIG. 1, a common electrode film 14 is formed on the connection electrode pad 12, and a projection electrode 17 is formed on the common electrode film 14. The top of the protruding electrode 17 is configured to be slightly higher than the top of the flow control film 15.

The protruding electrode 17 of the semiconductor device 10 and the substrate 22
Substrate electrode 23 and conductive particles 3 of anisotropic conductive adhesive 31
Connect at 1a.

The flow of the anisotropic conductive adhesive 31 is controlled by the flow control film 15 arranged on the short side of the semiconductor device 10 so that the flow becomes the same at any terminal of the semiconductor device 10.

As a result, the number of conductive particles 31a of the anisotropic conductive adhesive 31 captured between the protruding electrode 17 of the semiconductor device 10 and the substrate electrode 23 of the substrate 22 is ensured.

[Description of Method of Manufacturing Semiconductor Device: FIGS. 3 to 5] Next, a method of manufacturing a semiconductor device will be described. As shown in FIG. 3, in the semiconductor device 10, a connection electrode pad 12 made of aluminum is formed to a thickness of 1 μm on the element formation surface of a silicon substrate 11.

The connection electrode pads 12 are laid out on two long sides of the semiconductor device.

As shown in FIG. 4, a protective film 13 made of a silicon nitride film for protecting a semiconductor element is formed on the entire surface of the semiconductor device 10 including the connection electrode pads 12.

This protective film 13 is formed to a thickness of 1 μm by a plasma chemical vapor deposition method. The protective film 13
A silicon oxide film containing phosphorus may be formed by a chemical vapor deposition method.

After spin-coating a photosensitive resist (not shown), exposure and development are performed using a predetermined mask.

Further, an opening is formed in the protective film 13 so that the connection electrode pad 12 is exposed by a dry etching method using an etching gas containing carbon tetrafluoride as a main component.

Thereafter, the unnecessary photosensitive resist is removed with a resist stripper.

A flow control film 15 made of a photosensitive polyimide resin PIMEL (trade name) manufactured by Asahi Kasei is spin-coated on the entire surface of the semiconductor device 10 to a thickness of 14 μm.

Thereafter, an exposure and development process is performed using a predetermined mask, and the flow control film 15 is formed on two short sides of the semiconductor device 10.
Place.

Further, the common electrode film 14 is formed on the entire surface of the semiconductor device 10 by aluminum 1 μm, chromium 0.01 μm,
A metal multilayer film is formed of copper in a thickness of 1 μm sequentially by a method such as a sputtering method or a vacuum evaporation method.

Next, a plating resist 16 made of a thick liquid photosensitive resist is coated on the entire surface of the silicon substrate 11 to a thickness of 2 mm.
It is formed by spin coating at 0 μm.

Thereafter, an exposure and development process is performed using a predetermined photomask, and a rectangular opening having a side of 50 μm is formed in the plating resist 16 in the portion of the common electrode film 14 on the connection electrode pad 12 by a gap of 10 μm between terminals. To be provided.

Next, a non-cyanide-based gold plating solution was used for 0.1.
A protruding electrode 17 made of gold is formed at a thickness of 15 μm by electrolytic plating at 5 A / dm ² .

As shown in FIG. 5, the unnecessary plating resist 16 is removed with a stripping solution 104 (trade name) manufactured by Tokyo Ohka Kogyo.

Further, the common electrode film 14 other than the base of the protruding electrode 17 is removed. Copper, which is the upper layer metal of the common electrode film 14, is etched away using a copper etchant Enstrip C (trade name) manufactured by Meltex. Next, the chromium of the middle metal and the aluminum of the lower metal of the common electrode film 14 are etched with a mixed solution of cerium ammonium nitrate and potassium ferricyanide.

Although the common electrode film 14 has a film structure of aluminum, chromium, and copper, titanium, a titanium-tungsten alloy, nickel, and a nickel-vanadium alloy are also applicable.

[Method of Connecting Semiconductor Device to Substrate: FIG. 6]
Next, a method for connecting the semiconductor device to the substrate will be described. FIG.
As shown in FIG.
Is formed at a thickness of 0.2 μm.

Thereafter, patterning is performed by photolithography and etching to correspond to the protruding electrodes of the semiconductor device.

The anisotropic conductive adhesive 31 is arranged on the substrate 22. The anisotropic conductive adhesive 31 is obtained by mixing conductive particles 31a with an insulating resin made of epoxy resin, and is formed into a sheet having a thickness of 25 μm. The conductive particles 31a have an outer shape 5 in which two layers of nickel and gold are plated on the surface of plastic beads.
μm is used.

Next, the projecting electrode 17 of the semiconductor device 10 and the substrate electrode 23 of the substrate 22 are positioned and temporarily fixed on the anisotropic conductive adhesive 31.

The back surface of the semiconductor device 10 is
While applying a pressure of 400 kg / cm ²
Heating is applied at a temperature of 70 to 220 ° C. to cure the anisotropic conductive adhesive 31.

The gap between the semiconductor device 10 and the substrate 22, that is, the distance between the surface of the protective film 13 and the surface of the substrate 22 is changed by the heating and pressurizing treatment to cure the anisotropic conductive adhesive 31. The thickness is determined by the outer shape of the conductive particles 31 a of the anisotropic conductive adhesive 31 to be about 20 μm.

Since the thickness of the anisotropic conductive adhesive 31 before the heating and pressurizing treatment is 25 μm, the anisotropic conductive adhesive 31 corresponding to the thickness of 5 μm and the protrusion electrode 17 has the semiconductor device 10.
Flows out of the gap between the substrate and the substrate 22.

The flow of the anisotropic conductive adhesive 31 is controlled by the protruding electrodes 17 disposed on two long sides of the semiconductor device 10 and the flow control film 15 disposed on two short sides. The same anisotropic conductive adhesive 3 at any of the terminals 10
It becomes 1 flow.

As a result, the number of conductive particles 31a of the anisotropic conductive adhesive 31 captured between the protruding electrode 17 of the semiconductor device 10 and the substrate electrode 23 of the substrate 22 is ensured.

As described above, the flow control films 15 provided on the two short sides of the semiconductor device 10 allow the semiconductor device 1
It is possible to uniformly capture the conductive particles 31a of the anisotropic conductive adhesive 31 on all of the many protruding electrodes 17 on the two long sides of 0.

In the description of the embodiment of the present invention, when the size of the projecting electrode 17 is 50 μm on a side and a semiconductor device having a gap of 10 μm between adjacent terminals is mounted on the substrate, the flow control film 15 is connected to the semiconductor device 10. Placed on the two short sides of
A structure was used in which the top of the flow control film 15 was 3 μm lower than the top of the bump electrode 17.

However, the flow control film 15 is formed at substantially the same height as the top of the protruding electrode 17, and is a square having the same size and the same interval as the protruding electrode 17, 50 μm on a side, and a 10 μm gap between adjacent terminals. The same effect can be obtained by arranging a large number on two short sides of the device 10.

The flow control film 15 is arranged on two short sides of the semiconductor device 10, and the top of the flow control film 15 is lower than the top of the protruding electrode 17. Are formed at substantially the same height as the top of the projection electrode 17.
The structure in which a large number are arranged on two short sides of the semiconductor device 10 at the same size and at the same interval is selected depending on the height of the flow control film.

When the height of the flow control film is 10 μm or less, there is no difference between the two. However, when the height of the flow control film exceeds 10 μm, the flow control film 15
7 is formed at substantially the same height as the top of the semiconductor device 10, and a large number of the semiconductor devices 10 are arranged at the same size and at the same interval as the protruding electrodes 17.

That is, the flow control film 15 made of a photosensitive polyimide resin applied with a thickness of 10 μm is
It is very difficult to form them at the same size and at the same intervals.

Further, even if possible, a photosensitive polyimide resin having high sensitivity is very expensive and causes a problem in cost.

Further, as shown in FIG. 7, when the distance between the adjacent terminals is widened and the flow of the anisotropic conductive adhesive 31 changes due to wide open, the distance between the adjacent terminals and the open space is large. By providing the flow control film 15 in the semiconductor device, mounting that is not affected by the terminal layout of the semiconductor device 10 can be realized.

[0083]

As is clear from the above description, the mounting structure of the semiconductor device according to the present invention controls the flow of the anisotropic conductive adhesive 31 by the flow control film 15 disposed on the short side of the semiconductor device 10. The flow is the same at any terminal location of the semiconductor device 10. Which semiconductor device 1
Even with the terminal of 0, the conductive particles 31a of the anisotropic conductive adhesive 31 captured between the protruding electrode 17 of the conductor device and the substrate electrode 23 of the substrate 22 can be uniformly and sufficiently secured.

As a result, the connection area can be minimized, and a fine connection with low resistance and high reliability can be provided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a mounting structure of a semiconductor device according to an embodiment of the present invention.

FIG. 2 is a plan view showing a semiconductor device according to the embodiment of the present invention.

FIG. 3 is a cross-sectional view illustrating a method for manufacturing a semiconductor device according to an embodiment of the present invention.

FIG. 4 is a sectional view illustrating the method for manufacturing the semiconductor device according to the embodiment of the present invention.

FIG. 5 is a sectional view illustrating the method for manufacturing the semiconductor device according to the embodiment of the present invention;

FIG. 6 is a sectional view illustrating the method for manufacturing the semiconductor device according to the embodiment of the present invention;

FIG. 7 is a plan view showing a semiconductor device according to the embodiment of the present invention.

FIG. 8 is a plan view showing a semiconductor device for describing a problem to be solved by the invention in the related art.

FIG. 9 is a cross-sectional view showing a semiconductor device for explaining a conventional technique.

FIG. 10 is a cross-sectional view showing a semiconductor device for explaining a conventional technique.

FIG. 11 is a cross-sectional view showing a semiconductor device for explaining a conventional technique.

FIG. 12 is a cross-sectional view showing a mounting structure of a semiconductor device for explaining a conventional technique.

[Explanation of symbols]

Reference Signs List 10: semiconductor device 11: silicon substrate 12: connection electrode pad 13: protective film 14: common electrode film 15: flow control film 16: plating resist 17: projecting electrode 22: substrate 23: substrate electrode 3
1: Anisotropic conductive adhesive

Claims (7)

[Claims] A protection film having an opening on the connection electrode pad; a flow control film provided on the protection film in a portion other than the connection region in an outer peripheral portion of the semiconductor device; and a common electrode provided on the connection electrode pad. A semiconductor device comprising: a film; and a protruding electrode provided on the common electrode film. 2. The semiconductor device according to claim 1, wherein the flow control films are provided on two short sides of the semiconductor device. 3. The flow control film according to claim 1, wherein the gap between the protruding electrodes on the two short sides of the semiconductor device and the two long sides of the semiconductor device is provided in a region where the gap is wider than the width of the protruding electrodes. 3. The semiconductor device according to claim 1. 4. The semiconductor device according to claim 1, wherein the top of the flow control film is lower than the top of the protruding electrode. 5. The semiconductor device according to claim 1, wherein the height of the top of the flow control film is substantially the same as the height of the top of the protruding electrode. 6. The semiconductor device according to claim 1, wherein the flow control film is made of an organic material. 7. A step of forming a protective film on a semiconductor device having connection electrode pads and patterning the protective film so that the connection electrode pads are opened; a step of forming a flow control film on the semiconductor device; A step of patterning the film so as to be arranged in a portion other than the connection region in an outer peripheral portion of the semiconductor device; a step of forming a common electrode film on the semiconductor device; a step of forming a plating resist on the semiconductor device; Patterning a projection electrode forming region so as to be opened; forming a projection electrode by plating in a plating resist opening; removing a plating resist; and removing a common electrode film in a portion other than the base of the projection electrode. Removing the semiconductor device.