JPH04335544A - Semiconductor device and manufacture thereof - Google Patents

Abstract

PURPOSE:To enhance a quality of a semiconductor device manufactured by a simplified flip chip process in which a semiconductor chip is face down disposed on a main surface of a circuit board formed with a thick film conductive electrode through adhesive made of photo-setting insulating resin and the adhesive is then cured by irradiating with a light while applying a load to the chip. CONSTITUTION:A thick film conductive electrode of a connecting part is formed by coating with Au paste by a screen printing method, leveling it, drying it and then pressure molding it by a sawtooth-shaped pressing surface. Thereafter, a protrusion is formed by baking at a high temperature. Thus, a semiconductor device of a high quality in which defects of a semiconductor chip and an electric connection are reduced, is formed without applying an excess load.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to semiconductor packaging, and relates to a high-quality semiconductor device manufactured by a flip-chip mounting method, which is a simplified method, and a method for manufacturing the same.

0002

[Background Art] In recent years, semiconductor devices have become more compact due to the miniaturization of electronic equipment.
With the drop in prices, high-density mounting is increasingly being carried out using the flip-chip mounting method, which is a simplified method.

An example of flip-chip mounting, which is a simplified version of the conventional method described above, will be described below with reference to the drawings.

FIG. 6 is a perspective view of a semiconductor device manufactured using the flip-chip mounting method, which is a simplified version of the conventional method.
shows a sectional view of its main parts. Further, FIG. 8 shows a manufacturing process diagram of the circuit board, and FIG. 9 shows a schematic diagram of the shape of the thick film Au electrode on this circuit board. In FIGS. 6 and 7, 1 is a substrate made of a transparent glass material, 2 is a thick film Au electrode formed by a normal screen printing process, and 3 is a circuit conductor connected to this thick film Au electrode 2. It is a layer. This circuit conductor layer 3 is
A thick film lower Ag conductor 4 connected to the thick film Au electrode 2, a thick film insulating layer 5, a thick film upper Ag conductor 6 connected to an input/output terminal section to an external circuit, and this thick film upper Ag conductor 6. It is composed of a thick protective layer 7 for protection. 8 is a semiconductor chip,
Reference numeral 9 indicates an active element or a passive element formed using a semiconductor process. 10 is an insulating layer, and 11 is an Al wiring that electrically connects each element 9. 12 is a protective layer; 13 is an Al electrode formed on the surface of the protective layer 12 and connected to the Al wiring 11; 14 is an adhesive made of photocurable insulating resin.

A method for manufacturing the semiconductor device constructed as described above will be described below. A circuit board is prepared in advance. First, as shown in FIG. 8, a special Au paste is applied on the main surface of the substrate 1 by screen printing method, and after being left at room temperature for leveling,
Dry at 120-150℃ for about 10 minutes, then dry at about 500℃
The Au thick film electrode 2 is formed by firing at a temperature of about 100 mL. By repeating the same process, a thick film lower Ag conductor layer 4, a thick film insulating layer 5, a thick film upper Ag conductor layer 6, and a thick film protection layer 7 are sequentially formed to constitute the circuit conductor layer 3. Finally, it is scribed into individual pieces and used as circuit boards. FIG. 9 shows a schematic diagram of the shape of the thick film Au electrode 2 formed. next,
A protective layer 12 of a semiconductor chip 8 on which active elements and passive elements 9 and Al wiring 11 are formed using a semiconductor process.
An Al electrode 13 is formed on the surface. Next, as shown in FIGS. 7 and 8, a special Au paste is first applied on the main surface of the substrate 1 by screen printing, and leveling is performed by leaving it at room temperature. After that, 1 at 120-150℃
After drying for about 0 minutes, baking is performed at a temperature of about 500° C. to form the Au thick film electrode 2. By repeating the same process, a thick film lower Ag conductor layer 4, a thick film insulating layer 5, a thick film upper Ag conductor layer 6, and a thick film protection layer 7 are sequentially formed to constitute the circuit conductor layer 3. Finally, after forming these circuit conductor layers 3, scribing is performed to produce individual circuit boards. 7 and 9 show schematic diagrams of the shape of the thick film Au electrode 2 formed. Adhesive 14 is applied onto the main surface of this circuit board.
The semiconductor chip 8 is pressed face down onto the semiconductor chip 8 so that the Al electrode 13 and the thick film Au electrode 2 are in contact with each other. At this time, the adhesive 14 on the thick film Au electrode 2 is pushed away by the Al electrode 13, and the thick film Au electrode 2 and the Al electrode 13 are electrically connected. After that, the semiconductor chip 8
Pressure is applied from the side opposite to the element 9 surface to press the thick film Au electrode 2 and the Al electrode 13 together, and light is irradiated from the back surface of the circuit board 1 to harden the adhesive 14. In this way, the semiconductor chip 8 is mounted on the circuit board 1. At this time, in order to ensure a reliable electrical connection, the applied load must be applied so that the insulating oxide film that is naturally formed on the surface of the Al electrode 13 is physically It took just enough to destroy it.

(Japanese Unexamined Patent Publication No. 2-272764)

00
07]

[Problems to be Solved by the Invention] However, with the above structure, electrical connections may become disconnected due to changes over time due to internal stress accumulated in the thick-film Au electrode 2, or excessive contact may occur on the back surface of the semiconductor chip 8. Semiconductor chip 8 due to the load
This had the problem of damage to the

This is because the thick film Au electrode 2 formed by the normal screen printing method has very large variations in height as shown in FIG. 10(A). As shown in the figure, when all the electrodes are brought into contact with each other, the amount of deformation of the other thick-film Au electrode 2-b that matches the height of the lowest thick-film Au electrode 2-a increases, and the internal deformation caused by this increases. This is because the stress is extremely large and the load required from the back surface of the semiconductor chip 8 for this deformation is excessive. In addition, as shown in FIG. 9, the thick film Au electrode 2 formed by the normal screen printing method has a surface with few irregularities, so the contact area with the Al electrode 13 is wide and the oxide film is destroyed. This is because an excessive load is required on the semiconductor chip 8 when doing so.

SUMMARY OF THE INVENTION In view of the above problems, the present invention provides a high-quality semiconductor device manufactured by a flip-chip mounting method, which is a simplified method and reduces defects related to semiconductor chips and electrical connections.

0010

[Means for Solving the Problems] In order to solve the above-mentioned problems, the semiconductor device of the present invention includes a thick film Au electrode and a circuit conductor layer connected to the thick film Au electrode formed on the main surface of a transparent glass material. A semiconductor chip is placed face down on a circuit board and a predetermined position on the main surface of this circuit board via an adhesive made of photocurable insulating resin, and pressure is applied from the side opposite to the element surface of the semiconductor chip. Then, with the thick film Au electrode on the predetermined circuit board and the Al electrode formed on the element surface of the semiconductor chip in contact with each other, ultraviolet rays are irradiated from the back side of the circuit board to harden the adhesive and fix the semiconductor chip. , and a semiconductor mounting method for electrically connecting the semiconductor device, which includes a structure in which protrusions are formed on the surface of the thick film Au electrode.

[0011]

[Operation] According to the above-described structure, only the protrusions of the thick-film Au electrode are formed on the element surface of the semiconductor chip.
Contact with the electrode. Therefore, since the contact area is small,
The pressure required to destroy the oxide film requires less load on the semiconductor chip than in the past. Furthermore, when aligning the heights between the thick-film Au electrodes, only the protrusions are deformed, so the amount of deformation is small, the internal stress accumulated is also reduced, and the load applied to the semiconductor chip is also reduced. In this way, only the minute protrusions formed on the thick-film Au electrode are involved in electrical connection, so the pressure load on the semiconductor chip is less than before, and the amount of deformation of the thick-film Au electrode is also reduced. , semiconductor devices manufactured by flip-chip mounting using a simplified method can be of high quality.

0012

DESCRIPTION OF THE PREFERRED EMBODIMENTS A semiconductor device according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view of a semiconductor device according to an embodiment of the present invention, and FIG. 2 is a sectional view of a main part thereof. In addition, Fig. 3 shows a manufacturing process diagram for producing a circuit board, and Fig. 4 shows a schematic diagram of the shape of the pressing surface of a press machine for forming protrusions on a thick film Au electrode on a circuit board, and Fig. 4 (A) shows a perspective view. , (B) shows its cross-sectional view. In FIGS. 1 and 2, 21 is a substrate made of a transparent glass material, and 22 is a thick film of Au on which an Au paste is applied by ordinary screen printing, and after drying, protrusions are formed by pressing. 23 is a circuit conductor layer connected to the thick film Au electrode 22 on which the protrusion is formed. This circuit conductor layer 23 includes a thick film lower Ag conductor 24 connected to a thick film Au electrode 22 having a protrusion, a thick film insulating layer 25, and a thick film upper Ag conductor 24 connected to an input/output terminal portion to an external circuit. It consists of a conductor 26 and a thick film protective layer 27 that protects the thick film upper Ag conductor 26. 28 is a semiconductor chip, and 29 is an active element or a passive element using a semiconductor process. 30 is an insulating layer, 31 is each element 2
This is an Al wiring that electrically connects 9. 32 is a protective layer;
33 is formed on the surface of the protective layer 32 and the Al wiring 3
This is an Al electrode connected to 1. 34 is an adhesive made of photocurable insulating resin.

A method of manufacturing the semiconductor device constructed as described above will be described below with reference to FIGS. 3 and 4.

A circuit board is prepared in advance. First, Figure 3
As shown in Figure 2, a special Au paste is applied onto the main surface of the substrate using a screen printing method, and the paste is left at room temperature to perform leveling. After that, it is dried at 120 to 150° C. for about 10 minutes, and then pressed using a press having a serrated press surface as schematically shown in FIG. 4 to form a plurality of protrusions on the surface. Next, the Au is fired at a temperature of about 500°C.
A thick film electrode 22 is formed. A schematic diagram of the shape of the Au thick film electrode 22 formed at this time is shown in FIG. After that, in the same way as the conventional example, the normal screen printing process is used to print
Thick film lower Ag conductor 24, thick film insulating layer 25, thick film upper Ag
A conductor 26 and a thick film protective layer 27 are formed, a circuit conductor layer 23 is formed, and finally a circuit board is scribed into individual pieces. Next, on the main surface of such a circuit board,
A semiconductor device is manufactured by performing semiconductor flip-chip mounting using a simple method in the same manner as in the conventional example.

At this time, only the minute protrusions on the thick film Au electrode 22 come into contact with the Al electrode 33 and participate in electrical connection. In addition, by pressing with a high-precision press machine, variations in height can be made sufficiently small. Therefore, the amount of deformation of the thick film Au electrode 22 becomes small, and the load on the semiconductor chip 28 becomes sufficiently small. For these reasons, damage to the semiconductor chip 28 due to load and disconnection of electrical connections due to internal stress caused by deformation of the thick film Au electrode 22 are avoided.

As described above, according to this embodiment, in a semiconductor device manufactured by a simple flip-chip mounting method, during the process of forming thick film Au electrodes on the main surface of a circuit board by a normal screen printing method, After the process of drying the Au paste, a simple process of pressing with a serrated press to form protrusions is added, and for the reasons mentioned above, high quality semiconductor chips and electrical connections with few defects can be achieved. A semiconductor device can be obtained.

[0018]

Effects of the Invention As described above, the present invention provides a circuit board in which a conductive electrode having a protrusion and a circuit conductor layer connected thereto are formed on the main surface of a glass base material having a light-transmitting property; A semiconductor chip is placed face down at a predetermined position on the main surface of the circuit board via an adhesive made of photocurable insulating resin, and pressure is applied from the side opposite to the element surface of the semiconductor chip to secure the predetermined circuit board. With the upper thick-film conductive electrode and the electrode formed on the element surface of the semiconductor chip in contact with each other, ultraviolet rays are irradiated from the back side of the circuit board to harden the adhesive made of photocurable insulating resin and fix the semiconductor chip. A high-quality semiconductor device in which damage to the semiconductor chip and defects in electrical connection are reduced by forming conductive protrusions on the thick film conductive electrode in the electrically connected semiconductor device. It can be done.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a semiconductor device in an embodiment of the present invention.

FIG. 2 is a sectional view of a main part of the semiconductor device in the same embodiment.

FIG. 3 is a manufacturing process diagram of a circuit board of a semiconductor device in the same embodiment.

[Fig. 4] Au of the circuit board of the semiconductor device in the same example
FIG. 2 is a schematic diagram of the shape of a press surface of a press machine for forming a thick film electrode.

[Fig. 5] Au of the circuit board of the semiconductor device in the same example.
FIG. 3 is a schematic diagram of the shape of a thick film electrode.

FIG. 6 is a perspective view of a conventional semiconductor device.

FIG. 7 is a sectional view of a main part of a conventional semiconductor device.

FIG. 8 is a manufacturing process diagram of a circuit board of a conventional semiconductor device.

FIG. 9 is a schematic diagram of the shape of a thick-film Au electrode on a circuit board of a conventional semiconductor device.

FIG. 10 is an explanatory diagram of factors causing defects in a conventional semiconductor device.

[Explanation of symbols]

1, 21 Translucent glass substrate 2 Thick film Au electrode 3, 23 Circuit conductor layer 4, 24 Thick film lower Ag conductor 5, 25 Thick film insulating layer 6, 26 Thick film upper Ag conductor 7, 27 Thickness Film protective layer 8, 28 Semiconductor chip 9, 29 Element 10, 30 Insulating layer 11, 31 Al wiring 12, 32 Protective layer 13, 33 Al electrode

Claims (3)

[Claims] Claim 1: A circuit board in which a thick-film conductive electrode and a circuit conductor layer connected thereto are formed on the main surface of a glass substrate having light-transmitting properties; A semiconductor chip is placed face down via an adhesive made of photocurable insulating resin, and pressure is applied from the side opposite to the element surface of the semiconductor chip to connect the thick film conductive electrode on a predetermined circuit board and the semiconductor chip. Flip chip mounting, in which the semiconductor chip is fixed and electrically connected by irradiating ultraviolet rays from the back side of the circuit board with the electrodes formed on the element surface in contact with each other to harden the adhesive made of photocurable insulating resin. 1. A semiconductor device manufactured by a construction method, characterized in that a conductive protrusion is formed on the thick film conductive electrode. 2. The semiconductor device according to claim 1, wherein the thick film conductive electrode is made of Au. 3. The thick-film Au electrode is made by applying an Au paste by screen printing, leveling and drying, and then pressure-forming with a press having a serrated surface. 2. The semiconductor device according to claim 1, wherein the semiconductor device is formed by subsequently firing at a high temperature.