JPH01295444A - Manufacture of semiconductor device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Summary] Regarding the improvement of the external electrode structure of a semiconductor device with a chip structure, in the conventional structure, the metal bumps were deformed or deformed during a performance test, resulting in a decrease in the yield of the semiconductor device and damage to the external circuit. The purpose of this project is to provide a method for forming an electrode structure using bumps that solves the problem of poor connection reliability with external leads. A process of forming a bump connection part in which a bump is formed to be connected to the prober, and a pad part to which the stylus of the prober comes into contact; and a step of forming an insulating coating film covering the pad portion, forming an opening in the insulating coating film, and forming an electrode made of a barrier metal and a bump in the opening area. Contains and constitutes a method for manufacturing the device.

[Industrial application field]

The present invention relates to an improvement in the external electrode structure of a chip-structured semiconductor device.

2. Description of the Related Art Chip-structured semiconductor devices are used to increase the integration density of semiconductor devices and to increase the size and capacity of various information processing devices.

Performance tests for chip-structured semiconductor devices are performed using a stylus method using a prober before they are attached to an external circuit, but in this case, the external electrode portions, that is, the bump portions of the semiconductor device are likely to be damaged. There is a problem that the reliability of the connection decreases when a semiconductor device is attached to a wiring board of an information processing device etc. via a metal bump, so an external electrode structure that allows performance testing with a blower without damaging the bump part is needed. is requested.

[Conventional technology]

FIG. 3 is a schematic side sectional view of a main part showing the structure of a conventional bump portion in the semiconductor device having the above-mentioned chip structure.

In the figure, 11 is an interlayer insulating film, 12 is an upper layer aluminum (AJ) wiring, 13 is a covering insulating film, 14 is an opening in the covering insulating film that exposes the upper layer wiring, 15 is a barrier metal pattern, and 16 is a metal Showing bumps.

Conventionally, when forming the above-mentioned bump, after forming an opening 14 exposing a part of the upper layer AI wiring 12 on the covering insulating film 13, a barrier metal is formed on the covering insulating film 3 including the inside of the opening 14. Layer 15 is deposited by sputtering, vapor deposition, etc., a resist film having openings exposing the barrier formation region is formed on the barrier metal layer, and the resist film is electroplated using the resist film as a mask. For example, gold (Au) is placed inside the opening of
The metal bump 16 consisting of the above resist) MW is grown.
After removing the barrier metal layer, an exposed area of the barrier metal layer is selectively removed by etching using the metal (Au) bump 16 as a mask. Therefore, the conventional bump section has a structure in which a barrier metal pattern 5 is provided only at the lower part of the metal (Au) bump 5, as shown in the figure. Incidentally, an external lead 17 is finally connected to the bump 16 by thermocompression bonding to establish a connection with an external circuit.

[Problem that the invention seeks to solve]

When testing the performance of a conventional chip-structured semiconductor device using a prober prior to attachment to an external circuit, the test must be performed with the entire stylus placed over the metal bump 16. At this time, the prober is automatically moved toward the wafer on which the device shown in FIG. 3 is formed, and the stylus contacts the bump in this example. In order to ensure reliable conduction between the metal bumps 16 and the bumps, the stylus contacts the bumps with a certain force determined by the dimensions of the bumps. 16 is deformed and a uniformly good connection with the external circuit cannot be obtained, resulting in a problem that the reliability of the connection with the external circuit is reduced.

In addition, in order to prevent the metal bumps from falling off and deforming,
When the opening 14 exposing the Al wiring 12 is formed in the insulating film 13, a test is also carried out by setting the stylus of a prober on the exposed Al wiring. As shown in the cross-sectional view of FIG. 4(a) and the plan view of FIG. 4(b), a deep hole (or scratch) 18 is formed on the surface of the Al wiring 12 exposed within the opening, and as shown in FIG. 4(C). A cross-sectional view of (
As shown in the plan view of Al wiring 12, the barrier metal layer 15 deposited on the exposed surface of the Al wiring 12 has particularly thin parts or defective parts, impairing the barrier effect, and causing the Al wiring 12 and the metal ( There is a problem in that the metal (Au) bumps 16 react and the metal (Au) bumps tend to fall off. This is because, as mentioned above, when barrier metal is applied by sputtering or vapor deposition, the barrier metal does not adhere as well to stepped areas or areas with steep slopes as it does to flat areas. It is.

Furthermore, a method was also attempted in which the barrier metal layer was formed only over the opening in the coating insulating film and the test was conducted by setting the stylus of a prober on the barrier metal layer above the opening. The barrier metal layer is destroyed by the needle and loses its barrier function, and as above, A7! The reaction between the wiring and the metal (Au) bumps causes problems such as bumps falling off.

Therefore, the present invention solves the problem that, as described above, in the conventional structure, metal bumps may fall off or deform during performance tests, resulting in a decrease in the yield of the semiconductor device and a decrease in reliability of connection with external circuits. An object of the present invention is to provide a method for forming an electrode structure using bumps.

[Means for solving problems]

The problem described above is that the upper layer aluminum wiring formed on the interlayer insulating film on the semiconductor substrate is spread out to have a bump connection area where bumps are formed to connect to external leads and a pad area where the blower stylus comes into contact. forming a covering insulating film that covers the bump connection part and the pad part after bringing the stylus into contact with the pad part and performing a predetermined test; and forming an opening in the covering insulating film. The problem is solved by a method of manufacturing a semiconductor device, which includes a step of forming an electrode made of a barrier metal and a bump in a hole forming portion.

[Effect]

That is, in the present invention, an aluminum wiring is formed to include a bump connection portion and a pad portion that is in contact with a stylus, and the pad portion that is scratched by the stylus test is covered with a covering insulating film, and then the bump connection portion is formed. A hole is formed in the covering insulating film, and a bump is formed in the hole.

〔Example〕

Hereinafter, the present invention will be specifically explained with reference to an illustrated embodiment.

FIGS. 1(a) and 1(bl) are a sectional view and a plan view of an embodiment of the present invention.

In the conventional example, an element is formed on a semiconductor substrate (not shown), and an aluminum wiring 12 is formed on an interlayer insulating film 11 from phosphorous silicate glass (PSG) formed on the semiconductor substrate at a bump connection portion (opening 14). (the part where is made)
However, in the present invention, after forming up to the interlayer insulating film 11 in the same manner as in the conventional example, the aluminum wiring 21 is added to the bump connection part 22, and the aluminum wiring 21 is added to the bump connection part 22, and the aluminum wiring 21 is The AJ wiring 12 of the conventional example is formed into a long extended structure so as to have a band portion 23 that comes into contact with the needle.

The probe using the stylus is performed by bringing the stylus into contact with the pad portion 23. As a result, there are scratches 24 on the pad portion 23.
is added. As mentioned above, the formation of this scratch 24 is unavoidable with the current technology.

Next, a covering insulating film 13 is deposited. For example, PSG is deposited to a thickness of 1 μm by chemical vapor deposition (CVD).

In the CVD method, unlike in the case of sputtering or vapor deposition, a film is grown that completely covers the stepped portions and sloped portions of the scratches, so the scratches 24 are completely covered with the PSG coating insulating film.

Next, a hole 14 of, for example, about 50 to 100 μm angle is formed in the covering insulating film to expose the bump connection portion 22 by a normal lithography technique, and then a Ti film with a thickness of about 3000 mm is formed on the entire surface by a sputtering method. The covering insulating film 1 including the openings 14 is formed by successively depositing the PT layer and the PT layer.
A barrier metal layer 15 having a two-layer structure of Ti and PL is formed on the entire surface of the substrate 3. Subsequently, a barrier metal layer 15 and bumps 16 are formed in the same manner as in the conventional example.

According to the above-mentioned method, a probe is performed at the pad part of the AIl wiring 21, a covering insulating film is deposited covering the scratches formed at that time, and a hole is opened at the bump connection part of the covering insulating film to form a barrier metal and a bump. Therefore, a semiconductor device having a highly reliable electrode structure is provided without any scratches being made on bumps, barrier metals, or Affi wiring.

A variation of the invention is shown in plan view in FIG.

Generally, the pad portion is required to have a size that is at least a certain size in relation to the stylus, but the size of the bump connection portion 22 is in the range of 50 to 100 μ-square. Therefore, for example, when the bump portion 22 has a size of 50 μl square, the pad portion 23 may be formed large. In this way, it is also possible to form the bump connecting portion 22 and the bump portion 23 to the predetermined dimensions required for each, and the scope of the present invention is limited to the example shown in FIG. isn't it.

〔Effect of the invention〕

As described above, according to the present invention, the bumps are not scratched, so the external leads can be connected well, and the external leads can only be connected to chips that have been certified as good by the probe. , defective external lead connection,
Leads are not connected to defective chips, which is effective in reducing costs. Test data from the probe is fed back and bumps are formed only on good chips using a stepper, which completely avoids unnecessary work. .

[Brief explanation of the drawing]

FIG. 1 is a diagram of an embodiment of the present invention, in which (81 is a sectional view, (
b) is a plan view, Fig. 2 is a plan view of the modified side of the present invention, Fig. 3 is a sectional view of the conventional example, and Fig. 4 is a diagram showing the problems of the conventional example.
) is a cross-sectional view, (11) and (di are plan views. In the figure, 11 is an interlayer insulating film, 12 is A1 wiring, 13 is a covering insulating film, 14 is an opening, 15 is a barrier metal, and 16 is a bump) , 17 is an external lead, 1 is a scratch, 21 is an Al wiring, 22 is a bump connection part, and 23 is a pad part. Patent applicant Akira Kukimoto, Fujitsu Limited representative patent attorney □---- □1■ "Nininiyo and □■" Fig. 1 114 mound order 13 Supplementary f1 and t interpolation 14 Kanru] 15 Barrier metal 16 Bump. 21 A/DC line 22 No\'n7゛n and 1goF 23 Bird (p −η 1 changeffi NorsB , @, t Indication j J Conventional 1
1. Indication of the case 1988 Patent Application No. 26653 2. Title of the invention Method for manufacturing semiconductor devices 3. Make amendments Relationship with the Patent Case Patent Applicant Address 1015 Kamiodanaka, Nakahara-ku, Yozaki City, Kanagawa Prefecture (
522) Name Fujitsu Limited 4, Agent ■160 Telephone (03) 350
-0270 (Delivery date: July 4, 1999) 6. Drawings to be amended, drawing numbers of Figure 4 (for a and b) 7. Contents of the amendment As shown in the attached sheet, the issue of cover-up, ! Figure 4 shows the opening.

Claims (1)

[Claims] A bump connection portion (2) in which a bump (16) is formed to connect an upper layer aluminum wiring (21) formed on an interlayer insulating film (11) on a semiconductor substrate to an external lead (17).
2) and a pad portion (23) that the stylus of the prober comes into contact with.
) and perform the prescribed test, then the bump connection part (
22) and a step of forming a covering insulating film (13) covering the pad portion (23), forming an opening (14) in the covering insulating film (13), and forming a barrier metal (15) in the opening forming part. A method of manufacturing a semiconductor device, the method comprising the step of forming an electrode consisting of a bump (16).