JPH06151584A - Method for dicing semiconductor device - Google Patents

Abstract

PURPOSE:To prevent the occurrence of chipping of a substrate at dicing of a chip by covering a cutting path with an organic protective film, and sticking a chip fixing tape to the rear where the pattern of a wafer is not made, and shifting a dicing saw on a cutting path thereby dicing the chip. CONSTITUTION:There is a chip fixing tape 107 below a substrate 101, and a resin film 106 is made in the cutting path section, in the shape of sandwiching the substrate 101 together with it. The first protective film 105 for a chip is inorganic passivation such as PSG or the like, and is protecting one part of an oxide insulating film 102 and an interlayer insulating film 103, which constitute a chip, and an electrode lead-out terminal 104 of the chip. A resin film 106 is a material used as the protective film for the first protective film 105, and it can suppress the chipping of the substrate merely on the ground that a protective film exists a little on the cutting path.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device dicing method.

[0002]

2. Description of the Related Art Conventionally, when cutting (dicing) a semiconductor wafer into chips, a chip fixing tape is attached to the back surface of the wafer opposite to the pattern surface of the chips, and a dicing saw is applied from the pattern surface side. However, a protective film is not usually provided on the cutting path region between chips. Also, for example, Japanese Examined Patent Publication 3-43785
As seen in Japanese Patent Publication No. JP-A-2004-96242, a first protective film is formed on a portion other than the electrodes of the chip, and a second organic resin protective film is first formed to prevent intrusion of moisture from the edge of the chip and to prevent moisture. In some cases, the protective film was not coated on the cutting path. There is also a case where a chip fixing tape is attached to the chip pattern surface side. In that case, in order to improve the adhesiveness of the tape, the resin is placed on the cutting path between the chips at the same height as that on the chips. It covers so that it may be filled up, and the tape may be stuck on it.

[0003]

Here, if there is no protective film on the cutting path, the substrate will be chipped during chip dicing, so it is necessary to set the cutting path region with a margin so that the chip pattern is not destroyed. Further, usually, the first protective film is called a passivation protective film and is formed of a hard material of an inorganic insulating film. Therefore, there is a problem that the blade of the cutter is easily damaged when it is on the cutting path, and again, the cutting path is not covered. Further, as shown in FIG. 3, even when the resin film is formed as the second protective film for protecting the first protective film, there is no example in which the resin film is formed on the cutting path, and rather, for that reason. The cutting path width was wide. Also, when sticking the chip fixing tape to the chip side, it is not intended to protect the substrate with a sandwich structure but to improve the adhesiveness of the tape originally, and the organic protective film is up to the same height as the chip. Since it is covered, there is a problem that it is easier to peel off than when the protective film is thin.

[0004]

The structure of the present invention for solving the above problems is a dicing method in which a wafer on which a predetermined semiconductor element pattern is formed is cut with a dicing saw for each chip. A part or all of the cutting path is covered with an organic protective film so that the dicing saw does not directly contact the substrate on the path, and a chip fixing tape is attached to the back surface of the wafer on which no pattern is formed. It is characterized in that the dicing saw is moved to perform dicing.

[0005]

With the above structure, the chip fixing tape and the organic resin protective film protect the substrate in a sandwiched manner in the cutting path region, and the dicing saw does not directly contact the substrate to start cutting. During the cutting, the organic resin protective film, which is softer than the substrate, becomes finely inserted between the dicing saw and the substrate.

[0006]

By protecting the substrate in the cutting path region, chipping of the substrate can be suppressed, so that the cutting path region, which has been taken extra for safety, can be narrowed, and the chip occupancy ratio on the wafer can be reduced accordingly. In addition, since the organic resin protective film protects the chip, chipping and the like can be prevented even when assembling the package. Further, the organic resin plays the role of a lubricant, the shake of the cutter is weakened, the cutting margin is slightly narrowed, the life of the dicing saw is extended, the yield of semiconductor devices is improved, and the cost is reduced.

[0007]

EXAMPLES The present invention will be described below based on specific examples. FIG. 1 shows an embodiment of the present invention. There is a chip fixing tape 107 on the lower side of the substrate 101, and the resin film 106 is provided on the cutting path portion so as to sandwich the substrate with the chip fixing tape 107.
To form. 105 is the first protective film of the chip, namely PS
It is an inorganic passivation film such as G (phosphorus glass), and protects a part of the oxide insulating film 102, the interlayer insulating film 103, and the electrode lead-out terminal 104 of the chip which form the chip. The resin film 106 is a material originally used as a protective film for the first protective film 105. For the present invention, the presence of a slight protective film on the cutting path is effective, and therefore the design thereof is designed. Is mainly formed to protect the first protective film 105. A polyimide resin was used as the resin film material. It should be noted that the chip fixing tape 107 is used to prevent the chips from being separated after cutting.
Control the dicing saw so that it does not cut all of the tape, as in.

FIG. 1A is a cross-sectional view of the cutting path region of the wafer before being cut into chips, and W1 indicates the width of the cutting path region. FIG. 1 (b) shows a state after dicing, where W2 is a cutting width of the dicing saw and W3 is a chipping width of the substrate. As a comparison, FIG. 2 shows a conventional method without a protective film on a similar wafer. 2 (a) is before dicing and FIG. 2 (b) is after dicing. W4 is a cutting path width, W6 is a width of a chip without a protective film, and is larger than W3. Therefore, W4 is W
It was necessary to take more than 1. According to the inventors' actual measurement,
As shown in FIG. 6, the conventional chip width W6 was 20 μm at maximum and W3 was 5 μm or less, which was almost unobservable. Conventionally, W4 is about 90 μm if the overlap between the first protective film and the second protective film is 5 μm in the case of FIG. Although the width of the path was required, W1 in this example was 50 μm, which was a saving of 40% or more. Although W2 after cutting is the width of the dicing saw, it is slightly narrower than W5 in the conventional case. According to the actual measurement conducted by the inventors, the cutting width W5 was 42 μm with respect to the dicing saw width of 37.5 μm, but the cutting width W2 was 40 μm, and the improvement effect was obtained also in this respect. As described above, according to the present invention, the cutting path can be set narrow, and the chip integration rate on one wafer can be improved.

Further, according to this embodiment, the life of the dicing saw can be extended. As shown in FIG. 5, the result that the life is extended by 20% or more on average is obtained. This is considered to be because the resin plays a role of lubricating the substrate when the resin is hung on the dicing saw, and it is considered that chipping is unlikely to occur because of this.

As another embodiment of the present invention, as shown in FIG. 4, even if the resin film is not necessarily formed on the entire cutting path, the width indicated by W8 in FIG. If the sandwich structure is narrower than W2) of No. 1 and the region corresponding to the dicing saw is covered with the resin, the same effect is exhibited for the above reason. Further, the resin film is not limited to the polyimide resin, and may be a resin having heat resistance, adhesion, electrical insulation, elasticity, and cleanability.

[Brief description of drawings]

FIG. 1 is a sectional view of a semiconductor substrate showing an embodiment of the present invention.

FIG. 2 is a sectional view of a semiconductor substrate showing a conventional example.

FIG. 3 is a sectional view of a semiconductor substrate showing another conventional example.

FIG. 4 is a sectional view of a semiconductor substrate showing another embodiment of the present invention.

FIG. 5 is a comparison diagram of the number of times the dicing saw is used.

FIG. 6 is a comparative diagram of chip chip widths after cutting.

[Explanation of symbols]

 101 Semiconductor Substrate 102 Oxide Insulating Film 103 Interlayer Insulating Film 106 Resin Protective Film 107 Chip Fixing Tape

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshihiro Okumura 1-1-1, Showa-cho, Kariya city, Aichi prefecture Nihon Denso Co., Ltd.

Claims (1)

[Claims] 1. A dicing method for cutting a wafer on which a predetermined semiconductor element pattern has been formed into chips by a dicing saw so that the dicing saw does not come into direct contact with the substrate on the wafer cutting path. Dicing of a semiconductor device characterized by covering the top with an organic protective film, attaching a chip fixing tape to the back surface of the wafer on which no pattern is formed, and moving the dicing saw on the cutting path to perform dicing. Method.