JPH04356942A - Manufacture of semiconductor integrated circuit device - Google Patents

Abstract

PURPOSE:To prevent that the surface of a chip is contaminated with dust produced in a cutting and dividing operation and to obtain a semiconductor integrated circuit device whose reliability is high. CONSTITUTION:A sheet 12 for surface protective use is pasted on the surface of a semiconductor integrated circuit substrate 1. Only the semiconductor integrated circuit substrate 1 is cut into pieces from the rear side in such a way that the sheet is left; it is divided into semiconductor integrated circuit chips 1C; after that, the sheet 12 is stripped. Desirably, the sheet 1 is pasted on the surface of the substrate 1 via an ultraviolet curing adhesive P. The surface of the substrate is irradiated with ultraviolet rays before the sheet is stripped. The adhesive is hardened so that the sheet can be stripped easily.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a semiconductor integrated circuit device, and more particularly to a method of cutting a semiconductor integrated circuit board into chips.

0002

2. Description of the Related Art In recent years, in the field of semiconductor integrated circuits, the density and integration of elements have been increasing, and the miniaturization of elements has continued to progress.

[0003] Such semiconductor integrated circuit devices usually have
A large number of integrated circuits are fabricated on a semiconductor substrate such as a silicon substrate, and after completion, it is divided into semiconductor integrated circuit chips, these semiconductor integrated circuit chips are mounted on a mounting member such as a lead frame or a tape carrier, and the area around the chip is Obtained by sealing with resin or the like.

By the way, the process of dividing this integrated circuit board into semiconductor integrated circuit chips is normally carried out as follows.

As shown in FIG. 5(a), a surface protection sheet 2 is pasted on the semiconductor integrated circuit board 1 to prevent air bubbles from appearing, and a fixing sheet 7 is pasted on the back surface, and the semiconductor integrated circuit board 1 is placed on the suction stage 3. Attach circuit board 1 and attach suction hole 1
The semiconductor integrated circuit board 1 is fixed to the suction stage 3 by performing vacuum suction from zero.

[0006] Then, the thin blade cutter 4 is scanned while positioning is performed by the monitor TV5 through the TV camera, and the semiconductor integrated circuit board 1 is sequentially cut into semiconductor integrated circuit chips 1C. After dividing in this way, the surface protection sheet is peeled off and the sheet is transported to the mounting line, as shown in FIG. 5(b).

In this case, when the surface protection sheet is removed, the adhesive of the surface protection sheet may remain on the chip surface, or the chips 8 may remain raised beside the cutting line (scribe line), and when the surface protection sheet is removed, The chips 8 are pushed and fall down, and the fallen chips scatter, which may cause dust and dirt to adhere to the chip surface, as well as scratches. Conventionally, these have often caused adverse effects such as malfunction of semiconductor integrated circuits.

[0008] In order to reduce the generation of such chips, there is a method of cutting only half the thickness of the semiconductor integrated circuit board (half-cut) and then dividing it by applying pressure. Methods have been proposed, such as reducing the thickness of the circuit board from the beginning. However, the problem of chips scattering on the surface, adhesion of dust and dirt, and occurrence of scratches remains unresolved.

[0009]

[Problems to be Solved by the Invention] As described above, in the conventional cutting method, the chip surface may be contaminated with adhesive, or when the surface protection sheet is peeled off, the chips 8 may be pushed and fall down. There is a problem in that dust and dirt adhere to the chip surface and scratches occur due to the scattering of the chips, resulting in malfunction of the semiconductor integrated circuit.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to prevent the chip surface from being contaminated by chips during cutting and to obtain a highly reliable semiconductor integrated circuit device.

[0011]

[Means for Solving the Problems] Therefore, in the first aspect of the present invention, a surface protection sheet is pasted on the surface of a semiconductor integrated circuit board, and the semiconductor integrated circuit is The substrate is cut, and then the surface protection sheet is peeled off to obtain divided semiconductor integrated circuit chips.

[0012] Preferably, the sheet is attached using an ultraviolet curable adhesive, and prior to peeling, the surface of the semiconductor integrated circuit board is irradiated with ultraviolet rays to harden the ultraviolet curable adhesive, and the sheet is It is made to be in a state where it can be easily peeled off.

In the second aspect of the present invention, an adhesive layer is selectively formed along the area to be cut in an area slightly larger than the area to be cut, and the surface of the semiconductor integrated circuit board is bonded by this adhesive layer. A surface protection sheet is pasted on the surface protection sheet, the semiconductor integrated circuit board is cut together with the surface protection sheet to divide it into semiconductor integrated circuit chips, and then the surface protection sheet is peeled off. .

Furthermore, in the third aspect of the present invention, an ultraviolet curable adhesive is applied to the entire back surface of the surface protection sheet, and a light shielding layer is applied to the surface of the sheet in an area slightly larger than the area corresponding to the area to be cut. A film pattern is formed, and ultraviolet rays are irradiated using this light-shielding film pattern as a mask to selectively harden the UV-curable adhesive in areas other than the areas to be cut of the sheet, and then the sheet is placed on the surface of a semiconductor integrated circuit board. The semiconductor integrated circuit board is cut into semiconductor integrated circuit chips together with the surface protection sheet, and the surface protection sheet is then peeled off.

Preferably, prior to peeling, the surface of the semiconductor integrated circuit board is irradiated with ultraviolet rays to cure the ultraviolet curable adhesive and to make the sheet easy to peel, and then peeled off.

[0016]

[Operation] According to the first configuration, a surface protection sheet is attached to the front surface of the semiconductor integrated circuit board, and the semiconductor integrated circuit board is cut from the back side to be divided into semiconductor integrated circuit chips. Even if debris is generated, it is on the back side of the semiconductor integrated circuit board, and contamination on the front surface is reduced. Since the semiconductor integrated circuit board is cut from the back side so as to leave the surface protection sheet, the sheet remains as one piece after cutting and is easy to peel off.

[0017] Then, the sheet is attached using an ultraviolet curable adhesive, and prior to peeling off, the surface of the semiconductor integrated circuit board is irradiated with ultraviolet rays to harden the ultraviolet curable adhesive. This puts the sheet in a state where it is easy to peel off.

Further, according to the second configuration, an adhesive layer is selectively formed along the area to be cut in an area slightly larger than the area to be cut, and this surface protection sheet is attached to the semiconductor integrated circuit. Since it is attached to the surface of the substrate, when the semiconductor integrated circuit board is cut together with this surface protection sheet, the area near the cut surface is fixed by the adhesive layer, and the element area of the semiconductor substrate is protected by the adhesive layer. Since the surface is protected by the sheet that is fixed only on the side of the cut surface, it is not contaminated with chips or the like. Also,
By using an ultraviolet curing adhesive as the adhesive layer for fixing this surface protection sheet, it can be easily peeled off by irradiating it with ultraviolet light prior to peeling.

Further, in the third aspect of the present invention, an ultraviolet curing adhesive is applied to the entire back surface of the surface protection sheet, and a light shielding layer is applied to the surface of the sheet in an area slightly larger than the area corresponding to the area to be cut. A film pattern is formed, and ultraviolet rays are irradiated using this light-shielding film pattern as a mask to selectively harden the ultraviolet curable adhesive in areas of the sheet excluding the areas to be cut, and then this sheet is attached to a semiconductor integrated circuit board. By adhering it to the surface, when the semiconductor integrated circuit board is cut together with this surface protection sheet, the vicinity of the cut surface is fixed by the adhesive layer, and the elements of the semiconductor substrate are The area is adhered to the surface protection sheet only on the side of the cut surface without contaminating the surface with adhesive, and because it is protected by this adhesive layer and sheet, it is also free from contamination with chips etc. do not have. Also,
Here too, by performing ultraviolet irradiation prior to peeling,
Can be easily peeled off.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described in detail below with reference to the drawings.

Embodiment 1 FIG. 1 is a diagram showing a method of cutting a semiconductor integrated circuit board according to a first embodiment of the present invention.

First, as shown in FIG. 1(a), a surface protection sheet 12 made of polyethylene or polyolefin film with a thickness of 80 μm is placed on the surface of a semiconductor integrated circuit board 1 such as a silicon IC, that is, on the side on which the integrated circuit is formed.
are attached using a 10 μm thick ultraviolet curable adhesive P to prevent air bubbles from appearing. Then, this semiconductor integrated circuit board 1 is mounted on a suction stage 13 made of an infrared transparent material such as glass with the surface of this semiconductor integrated circuit board 1 facing down, and vacuum suction is performed from the suction hole 10.
The semiconductor integrated circuit board 1 is fixed on the suction stage 13. Here, as the surface protection sheet 12 and the ultraviolet curable adhesive P, an ultraviolet curable dicing sheet manufactured by Lintec and designated as D-604MS, in which both are integrated, was used.

Then, an infrared lamp 1 is inserted from the front side of the substrate.
6, the integrated circuit board 1 is irradiated with light, and the transmitted light is used to monitor the pattern of the scribe line 9 formed on the circuit board 1 using an infrared vidicon camera.
5, the thin blade cutter 4 whose height has been adjusted while positioning is scanned to sequentially cut the semiconductor integrated circuit substrate 1 and divide it into semiconductor integrated circuit chips 1C. At this time, the surface protection sheet 12 is left uncut.

After dividing in this way, stage 1
As shown in FIG. 1(b), a fixing sheet 7 is attached to the back side of the semiconductor integrated circuit board 1 while the semiconductor integrated circuit board 1 is still fixed to the substrate 3. This fixing sheet 7 also has a thickness of 80 μm like the surface protection sheet 12.
It is made of polyethylene or polyolefin film and is attached with an ultraviolet curable adhesive (not shown).

Then, as shown in FIG. 1(c), UV irradiation is performed from the front side of the semiconductor integrated circuit board 1.

Here, the ultraviolet curing adhesive P is shown in FIG.
), it hardens and changes state to become P',
When the adhesive strength decreases and it becomes easy to peel off,
The surface protection sheet 12 is peeled off all at once. Here, the adhesive strength of the UV-curable adhesive of the fixing sheet 7 also decreases in areas exposed to light, but in this case, the UV irradiation is from the front side of the substrate, that is, the side on which the integrated circuit is formed, so the chip Light is blocked in a certain area of the wiring pattern, and the adhesive state can be maintained.

[0027] Then, it is conveyed to the mounting line while being fixed on the fixing sheet 7.

Then, the fixing sheet 7 is stretched, the interval between the chips is increased, and the U
V irradiation is performed to cure the film in the same manner, and when the adhesive strength is reduced and it becomes easy to peel off, the film is transferred one by one using a collet, positioned and mounted on a lead frame or film carrier, etc.

The semiconductor integrated circuit chip formed in this manner can be obtained without any chips adhering to the surface, and can maintain a good surface condition.

[0030]Furthermore, since the sheet remains in one piece without being divided, and the adhesive force of the surface protection sheet can be reduced by UV irradiation, the surface protection sheet can be easily peeled off.

[0031] Here, in order to detect the scribe line from the back side of the semiconductor integrated circuit board, a suction stage made of an infrared transparent material such as glass is used, infrared rays are irradiated from the bottom side, and transmitted light is detected. I tried, but
The detection means may be placed on the lower side to detect reflected light.

Embodiment 2 FIG. 2 is an explanatory diagram showing a method of cutting a semiconductor integrated circuit board according to a second embodiment of the present invention, and FIGS. 3(a) to 3(i) are cross-sectional views of this process.

In this method, the adhesive layer 23 is selectively formed along the cutting line, that is, the area 24 to be cut, in an area slightly larger than the area to be cut, and this adhesive layer 23 is
A surface protection sheet 25 is pasted on the surface of the semiconductor integrated circuit board 11, and together with this surface protection sheet,
This method is characterized in that a semiconductor integrated circuit board is cut and divided into semiconductor integrated circuit chips, and then a surface protection sheet is peeled off. Here, 22 is an element area, that is, an area where the surface should be protected.

First, as shown in FIG. 3(a), a semiconductor integrated circuit substrate 11 on which an integrated circuit 22 such as a silicon IC is formed is formed. Here, 24 is a cutting line, that is, a region to be cut in the dicing process.

Next, as shown in FIG. 3(b), a surface protection sheet 25 made of polyethylene or polyolefin film with a thickness of 80 μm is formed by a printing method to be approximately 60 μm larger than the cutting area 24 of the semiconductor integrated circuit board 11. A lattice pattern 23 made of ultraviolet curing adhesive with a thickness of 50 μm is formed, and this pattern 2
3 is fixed so as to coincide with the cutting area 24 of the semiconductor integrated circuit board 11. The fixed state is shown in Figure 3(c).

Thereafter, the semiconductor integrated circuit board 11 is mounted with the back side facing down on the fixing sheet 17 mounted on the suction stage, and the semiconductor integrated circuit board 11 is placed on the fixing sheet 17.
3(d) using the dicing machine 18.
Dicing is performed from the surface of the substrate as shown in . At this time, since adhesive remains on the cut surface, the element area is well protected.

Thereafter, the surface of the substrate is irradiated with ultraviolet rays for about 5 seconds to cure the adhesive and reduce its adhesive properties. Here, as shown in Figure 3(e), the ultraviolet curable adhesive hardens and changes its state to become P', reducing its adhesive strength.
It becomes easy to peel off.

Then, as shown in FIG. 3(f), an adhesive tape 20 is attached to the surface of the surface protection sheet 25, and the surface protection sheet 25 is peeled off all at once.

[0039] Then, it is conveyed to the mounting line while being fixed on this fixed sheet 17. and Figure 3(g)
As shown in Figure 3(h), the fixing sheet 17 is stretched to increase the inter-chip spacing, and as shown in Figure 3(h), UV irradiation is applied again from the adhesive side, that is, the back side of the substrate, and the adhesive is cured in the same manner. When the force decreases and the film becomes easy to peel off, the collet 21 is used to transport the film one by one as shown in FIG. 3(i), position it on a lead frame or film carrier, and mount it.

The semiconductor integrated circuit chip thus formed can be obtained without the surface of the element region being contaminated with adhesive or adhering to chips, and can maintain a good surface condition. Can be done.

In this example, an ultraviolet curable pattern is used as the adhesive, but it is not necessarily an ultraviolet curable pattern, and a normal adhesive may be used. Further, when forming a pattern, not only a screen printing method but also a mask coating method in which coating is applied via a mask pattern, etc. may be used.

Embodiment 3 FIGS. 4(a) to 4(i) are process cross-sectional views showing a method for cutting a semiconductor integrated circuit board according to a third embodiment of the present invention.

In Example 2, a pattern of adhesive was printed, but in this method, a surface protection sheet 35 coated with an ultraviolet curable adhesive 33 on the entire back side is used, and a semiconductor integrated circuit board is printed on the surface of this sheet 35 for surface protection. A light-shielding pattern 30 is selectively formed along the cutting line, that is, the region 34 to be cut, in an area slightly larger than the region to be cut, and the adhesive function is selectively enhanced by exposure through this light-shielding pattern 30. The adhesive region 33S is left in a pattern, and the other features are as in Example 2.
It is similar to Here, 32 is an element area, that is, an area where surface protection is to be performed.

First, as shown in FIG. 4(a), the thickness is 80 mm.
The entire back surface of the surface protection sheet 25 made of polyethylene or polyolefin film with a thickness of 50 μm
An ultraviolet curable adhesive 33 is applied to the surface, and the area 60
A lattice-like pattern 30 of a light-shielding film made of Cr and having a thickness of 50 μm is formed with a thickness of about 1 μm.

Thereafter, as shown in FIG. 4(b), ultraviolet rays are irradiated from the surface side to form the lattice pattern 30 of the light shielding film.
The ultraviolet curable adhesive in the area other than under the lattice pattern 30 is cured, leaving only the area under the grid pattern 30 as an adhesive area 33S.

After this, as shown in FIG. 4(c), an adhesive area is formed on the back side of the sheet so as to form a pattern in an area slightly larger than the area corresponding to the area to be cut in the cutting process. The remaining sheet is fixed so that the patterned adhesive area 33S corresponds to the cutting area 34 of the semiconductor integrated circuit board 31. An integrated circuit 3 such as a silicon IC is provided on the surface of this semiconductor integrated circuit board 31.
2 is formed. Here, 34 is a cutting line, that is, a region to be cut in the dicing process.

The fixed state is shown in FIG. 4(d).

Thereafter, the semiconductor integrated circuit board 31 is mounted with the back surface facing down on the fixing sheet 17 mounted on the suction stage, and the semiconductor integrated circuit board 31 is placed on the fixing sheet 17.
4(e) using the dicing machine 38.
Dicing is performed from the surface of the substrate as shown in . At this time, since the adhesive region 33S remains on the cut surface, the element region is well protected.

Thereafter, as shown in FIG. 4(f), the substrate surface is irradiated with ultraviolet rays from an oblique direction for about 5 seconds to harden the adhesive in the adhesive region 33S and reduce its adhesiveness.

Then, as shown in FIG. 4(g), the adhesive tape 20 is attached to the surface of the surface protection sheet 35, and the surface protection sheet 35 is peeled off all at once.

[0051] Then, it is conveyed to the mounting line while being fixed on this fixed sheet 17. And Figure 4(h)
As shown in Figure 4(i), the fixing sheet 17 is stretched to increase the inter-chip spacing, and as shown in Figure 4(i), UV irradiation is performed again from the adhesive side, that is, the back side of the substrate, and the adhesive is cured in the same manner. When the force decreases and it becomes easy to peel off, as shown in FIG. 4(j), the collets 21 are used to transport the pieces one by one, position them on a lead frame or tape carrier, and mount them.

The semiconductor integrated circuit chip thus formed can be obtained without the surface of the element region being contaminated with adhesive or adhering to chips, and can maintain a good surface condition. Can be done.

[0053]

[Effects of the Invention] As explained above, the first aspect of the present invention
According to the above, a surface protection sheet is pasted on the front surface of a semiconductor integrated circuit board, and only the semiconductor integrated circuit board is cut leaving this sheet from the back side, dividing into semiconductor integrated circuit chips, and then Since this sheet is peeled off, contamination on the surface of the semiconductor integrated circuit board is reduced, and reliability can be improved.

According to the second aspect of the present invention, an adhesive layer is selectively formed along the area to be cut in an area slightly larger than the area to be cut, and this surface protection sheet is used as a semiconductor integrated circuit. Since it is attached to the surface of the substrate, when the semiconductor integrated circuit board is cut together with this surface protection sheet, the area near the cut surface is fixed by the adhesive layer, and the element area of the semiconductor substrate is protected by the adhesive layer. Since the cut surface is fixed to the surface protection sheet only on the side surfaces of the cut surface without being contaminated by chips, and is protected by the adhesive layer and the sheet, it is not contaminated with chips or the like.

According to the third aspect of the present invention, an ultraviolet curing adhesive is applied to the entire back surface of a surface protection sheet, and an area slightly larger than the area to be cut is applied to the surface of the sheet. A light-shielding film pattern is formed, and ultraviolet rays are irradiated using this light-shielding film pattern as a mask to selectively harden the UV-curable adhesive in areas other than the areas to be cut on the sheet, and then this sheet is attached to a semiconductor integrated circuit board. Therefore, when the semiconductor integrated circuit board is cut, the area near the cut surface is fixed by the adhesive layer, and the surface of the element area of the semiconductor board may be contaminated by the adhesive. Since it is protected by a surface protection sheet, there is no chance of contamination with chips or the like.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a cutting process of a semiconductor integrated circuit device according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a method for cutting a semiconductor integrated circuit device according to a second embodiment of the present invention.

FIG. 3 is a diagram showing a cutting process of a semiconductor integrated circuit device according to a second embodiment of the present invention.

FIG. 4 is a diagram showing a cutting process of a semiconductor integrated circuit device according to a third embodiment of the present invention.

FIG. 5 is a diagram showing a cutting process of a conventional semiconductor integrated circuit device.

[Explanation of symbols]

1 Semiconductor integrated circuit board 1C Chip 2　Surface protection sheet 3 Adsorption stage 4 Thin blade cutter 5 TV camera 6 Infrared lamp 7 Fixed sheet 8 Chips 9 Scribe line 10 Suction hole 11 Semiconductor integrated circuit board 12　Surface protection sheet 13 Adsorption stage 15 TV camera 16 Infrared lamp 17 Fixed sheet P　UV curing adhesive 23 Adhesive layer 24 Cutting line 25 Surface protection sheet 31 Semiconductor integrated circuit board 32 Element area 33S Adhesive area 34 Cutting line

Claims (5)

[Claims] 1. A method for manufacturing a semiconductor integrated circuit device in which a semiconductor integrated circuit board is divided into a plurality of semiconductor integrated circuit chips, a sheet adhering step of adhering a surface protection sheet to the surface of the semiconductor integrated circuit board; A cutting step of cutting the semiconductor integrated circuit board from the back side and dividing it into semiconductor integrated circuit chips so as to leave a surface protection sheet; and a peeling step of peeling off the surface protection sheet. A method for manufacturing a semiconductor integrated circuit device characterized by: 2. The sheet adhering step is a step of adhering a surface protection sheet via an ultraviolet curable adhesive, and prior to the peeling step, the surface of the semiconductor integrated circuit board is irradiated with ultraviolet rays. 2. The method of manufacturing a semiconductor integrated circuit device according to claim 1, further comprising an ultraviolet irradiation step of curing the ultraviolet curable adhesive and making the sheet easy to peel. 3. In a method for manufacturing a semiconductor integrated circuit device in which a semiconductor integrated circuit board is divided into a plurality of semiconductor integrated circuit chips, selectively cutting is performed along an area to be cut in a cutting step in an area slightly larger than the area to be cut. a sheet adhering step of forming an adhesive layer on the substrate and adhering a surface protection sheet to the surface of the semiconductor integrated circuit board using the adhesive layer; and cutting the semiconductor integrated circuit board together with the surface protection sheet. A method for manufacturing a semiconductor integrated circuit device, comprising: a cutting step of dividing the semiconductor integrated circuit into chips; and a peeling step of peeling off the surface protection sheet. 4. A method for manufacturing a semiconductor integrated circuit device in which a semiconductor integrated circuit board is divided into a plurality of semiconductor integrated circuit chips, an adhesive application step of applying an ultraviolet curable adhesive to the entire back surface of a surface protection sheet; A light-shielding film pattern is formed on the surface of the sheet in an area slightly larger than the region to be cut in the cutting step, and ultraviolet rays are irradiated using this light-shielding film pattern as a mask to cut the area of the sheet to be cut. an ultraviolet irradiation step for selectively curing the ultraviolet curable adhesive in the area to be removed; a sheet adhesion step for adhering the sheet to the surface of the semiconductor integrated circuit board; and a surface protection sheet for the semiconductor integrated circuit board. A method for manufacturing a semiconductor integrated circuit device, comprising: a cutting step of cutting a substrate into semiconductor integrated circuit chips; and a peeling step of peeling off the surface protection sheet. 5. Prior to the peeling step, the method includes an ultraviolet irradiation step of irradiating the surface of the semiconductor integrated circuit board with ultraviolet rays to cure the ultraviolet curable adhesive and make the sheet easy to peel. Characteristic claim (4)
A method of manufacturing the semiconductor integrated circuit device described above.