JP2566606B2 - Method for manufacturing semiconductor device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Outline] A method of irradiating ultraviolet rays to facilitate peeling of chips after dicing a wafer adhered to an ultraviolet curable tape, which substantially limits heating of the ultraviolet curable tape. In order to do so, the semiconductor wafer adhered on the ultraviolet curable tape stretched on the frame is scribed and divided into a plurality of chips, and the tape is irradiated with ultraviolet rays to reduce the adhesive force, In the method for manufacturing a semiconductor device that is more easily peeled off from the tape, water cooling the ultraviolet curable tape,
In this state, the tape is configured to be irradiated with ultraviolet rays.

[Industrial applications]

The present invention relates to a method of dicing a wafer adhered to an ultraviolet curable tape and then irradiating it with ultraviolet rays so as to facilitate chip separation.

A semiconductor device is manufactured by scribing a wafer to divide it into a plurality of chips, picking up each chip, incorporating it into a package, wire bonding, and sealing with a resin.

The chip pickup is performed by the pickup device by recognizing the position of the chip to be picked up by the recognition device.

Therefore, at the time of pick-up, it is necessary that the chip is in a state where it can be easily peeled off and that the position is accurately recognized.

An ultraviolet curable tape (hereinafter referred to as a UV tape) has a structure that has an adhesive layer on the base that cures when exposed to ultraviolet light. When exposed to ultraviolet light, the adhesive layer cures and the chip peels off. It becomes easy to do.

The base of the UV tape is made of a soft material, such as polypropylene or vinyl chloride, which is easily stretched so that the chip can be easily picked up.

In this case, the UV tape is slack and some chips are inclined, which makes it difficult to accurately recognize the position. Further, the chips may contact with the adjacent chips and be chipped due to the inclination of the chips. This tendency becomes remarkable when a wafer having a large diameter is used.

Therefore, it is necessary to prevent the UV tape from being heated as much as possible during the irradiation of the ultraviolet rays.

[Conventional technology]

FIG. 5 is a diagram showing an ultraviolet ray irradiation step which is a main part of a conventional semiconductor device manufacturing method.

In the figure, 1 is a wafer supporting device, and a UV tape 2 is stretched around a frame 3. Reference numeral 4 denotes a wafer, which is bonded to the UV tape 1 and is diced and fully cut as shown in an enlarged view in FIG.
Is divided into

For the UV tape 1, as shown in FIG.
Is irradiated.

Reference numeral 6 denotes an ultraviolet irradiation device, which comprises an ultraviolet lamp 7 and a lamp house 8.

Reference numeral 9 is a slit plate, 10 is a slit, 11 is a shutter for opening and closing the slit 10, and 12 is a quartz glass plate having an ultraviolet transmittance of 93%.

UV tape 1 is UV 7a while shutter 11 is open.
Is irradiated.

[Problems to be Solved by the Invention]

Since the UV lamp 7 also radiates infrared rays, UV tape 1
Are heated and sag due to the weight of the stretched wafer as shown in FIG. 7, and the chip indicated by reference numeral 5a becomes particularly inclined.

Therefore, when the position of the chip 5a is recognized by the recognition device 13, it becomes inaccurate, and the chip 5a cannot be picked up normally, or the chip 5a is not picked up at the time of picking up.
There was a problem of scratching.

Further, the edge of the chip 5a may come into contact with the adjacent chip 5b to cause chipping.

It is an object of the present invention to provide a method of manufacturing a semiconductor device, which can substantially prevent the UV tape from being heated.

[Means for solving the problem]

The present invention scribes a semiconductor wafer adhered on an ultraviolet curable tape stretched around a frame into a plurality of chips, irradiates the tape with ultraviolet rays to reduce the adhesive force, and the chips are adhered to the tape. In the method of manufacturing a semiconductor device that facilitates peeling, the ultraviolet curable tape is water-cooled, and in this state, the tape is irradiated with ultraviolet rays.

[Action]

Since the ultraviolet curable tape is in a water-cooled state, it is possible to reliably prevent the temperature of the tape from rising to the temperature at which the tape is stretched by the irradiation of ultraviolet rays.

Therefore, the chips remain flat and normally aligned even after the UV irradiation process.

〔Example〕

FIG. 1 is a diagram showing an ultraviolet irradiation step which is a main part of a method for manufacturing a semiconductor device according to an embodiment of the present invention. Third
FIG. 4 and FIG. 4 are a plan view and a front view of an apparatus for performing an ultraviolet irradiation process. FIG. 5 is a diagram showing the state of the UV tape after irradiation with ultraviolet rays. In each drawing, the same reference numerals are given to the constituent parts shown in FIGS. 5 and 6 and the consent constituent parts, and the description thereof will be omitted.

In FIGS. 1, 3, and 4, reference numeral 20 denotes a chamber, which is moved on the slit plate 9 in the direction of arrow 23 by the ball screw 22 driven by the motor 21 and passes over the slit 10.

The chamber 20 has a dish-shaped recess 24 having a bottom plate made of a quartz glass plate 25, a frame support portion 26 at the edge of the recess 24, a supply port 27 as an example, and a discharge port 28 at the other side. Have.

30 is a tank that is stored with pure water. 31 and 32 are hoses, which are connected between the tank 30 and the supply port 27 and the discharge port 28.

The pure water in the tank 30 is supplied with a hose 31, as shown by an arrow 33.
The pure water 33 is continuously circulated through the recess 24 and the hose 32, and the pure water 33 flows in the recess 24 at a predetermined water level H (determined by the positions of the discharge port 28 and the supply port 27) as indicated by the arrows. It is always stored in the state of being.

The frame support portion 26, when supporting the frame 3,
The UV tape 2 has a predetermined height with respect to the water level H so that the lower surface 2a of the UV tape 2 comes into contact with pure water.

The wafer supporting device 1 is mounted on the chamber 20 with the frame 3 supported by the frame supporting portion 26. The entire lower surface 2a of the UV tape 2 is in contact with the water surface of the pure water 33 in the recess 24, and the UV tape 2 is cooled by the pure water 33.

The UV tape 2 is adhered to the frame 3 over the entire surface, the pure water 33 does not enter the upper surface side of the UV tape 2, and the wafer 4 (chip 5) does not come into contact with the pure water.

The UV tape 2 remains in the chamber 20 while being cooled by pure water 33.
Move with.

When the chamber 20 approaches the slit 10, the shutter 11 opens, and the UV tape 2 passes the slit 7 and the ultraviolet rays 7a.
Is irradiated.

The ultraviolet rays 7a pass through the quartz glass plate 12, go out of the slit 10, pass through the quartz glass plate 25, pass through the pure water 33, reach the UV tape 2, and irradiate this.

The presence of the pure water 33, which has a transmittance of 100% of ultraviolet rays, does not reduce the amount of ultraviolet rays 7a to the UV tape 2.

UV tape 2 is irradiated with the same amount of ultraviolet rays as in the conventional case,
The chip 5 in which the adhesive layer is cured is in a state of being easily peeled off.

UV tape 2 is about to be heated, but UV tape 2
The bottom surface of the UV tape 2 comes into contact with the flowing pure water 33 and becomes strongly cooled, and the temperature of the UV tape 2 does not rise.
Does not grow.

FIG. 4 shows the wafer support 1 that has undergone the ultraviolet irradiation process. The UV tape 2 is hardly stretched, the chips 5 are aligned in a horizontal posture, and each chip 5 is recognized by the recognition device 13 with high positional accuracy.

Therefore, no pick-up error occurs and each chip is normally picked up.

Also, the edges of adjacent chips do not touch each other,
No chipping occurs.

[Effects of the Invention] As described above, according to the present invention, since the heating of the ultraviolet curable tape is substantially limited in the ultraviolet irradiation step, the tape does not stretch, and the adjacent chips There is no contact, and chipping of the chip due to contact can be prevented. Also, since the tape does not stretch, each chip can be easily peeled off and the position can be accurately recognized, and it is possible to eliminate chip pick-up mistakes and to pick up the chips when picking up. It is possible to obtain a good-quality semiconductor device without the risk of damaging the semiconductor device.

[Brief description of drawings]

FIG. 1 is a diagram showing the state of ultraviolet irradiation in the method for manufacturing a semiconductor device of the present invention, FIG. 2 is a plan view of an apparatus for carrying out the ultraviolet irradiation step of the manufacturing method of the present invention, and FIG. 3 is shown in FIG. 4 is a front view of the apparatus shown in FIG. 4, FIG. 4 is a view showing a state of the wafer supporting apparatus after being irradiated with ultraviolet rays in the manufacturing method of the present invention, and FIG. 5 is a state of ultraviolet irradiation in the conventional method for manufacturing a semiconductor device. 6 and 6 are views showing the wafer support device before ultraviolet irradiation, and FIG. 7 is a view showing the state of the wafer support device after ultraviolet irradiation in the conventional manufacturing method. In the figure, 1 is a wafer supporting device, 2 is a UV tape, 3 is a frame, 4
Is a wafer, 5 is a chip, 6 is an ultraviolet irradiation device, 7 is an ultraviolet lamp, 7a is ultraviolet, 20 is a chamber, 24 is a dish-shaped recess,
25 is a quartz glass plate, 26 is a frame support part, 27 is a supply port,
28 is a discharge port, 30 is a tank, and 33 is pure water.

Claims (1)

(57) [Claims] 1. A semiconductor wafer (4) adhered onto an ultraviolet curable tape (2) stretched around a frame (3) is scribed to divide it into a plurality of chips (5), and the tape is exposed to ultraviolet light. In the method for manufacturing a semiconductor device, which reduces the adhesive strength by irradiation and makes it easier to peel off the chip from the tape, the ultraviolet curable tape is water-cooled (20, 24, 33), and in this state, ultraviolet rays ( 7a) is irradiated, The manufacturing method of the semiconductor device characterized by the above-mentioned.