KR101660687B1

KR101660687B1 - Method for surface mounting of semiconductor chip

Info

Publication number: KR101660687B1
Application number: KR1020150052216A
Authority: KR
Inventors: 백명호; 여준동
Original assignee: 백명호
Priority date: 2015-04-14
Filing date: 2015-04-14
Publication date: 2016-09-28

Abstract

The present invention relates to a surface mounting method for a semiconductor chip, and more specifically, to a surface mounting method for a semiconductor chip, to attach a thermal release tape on a surface having a bump of a wafer formed thereon and perform inversion to perform a surface mounting process very simply. According to the present invention, the method comprises the following steps: 1) attaching an ultraviolet (UV) curable tape on the opposite surface of a surface having a bump of a wafer formed thereon; 2) attaching a thermal release tape on the surface having the bump of a wafer formed thereon; 3) vertically inverting the wafer; 4) irradiating the wafer with UV to cure the UV curable tape; 5) removing the UV curable tape; 6) applying heat to degrade the adhesive force of the thermal release tape; and 7) separating individual chips from the wafer to mount the chips on a surface of a substrate.

Description

TECHNICAL FIELD [0001] The present invention relates to a method of mounting a semiconductor chip on a semiconductor chip,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a semiconductor chip surface mounting method, and more particularly, to a semiconductor chip surface mounting method capable of performing a surface mounting process very simply by attaching a heat releasable tape to a surface of a wafer on which bumps are formed .

As is well known, in the surface mounting process, a solder is printed on a land of a printed circuit board, the lead of the surface mounting element such as a semiconductor chip is mounted on the printed solder land, and a printed circuit board And the solder is melted and bonded by applying infrared radiation to connect the leads of the surface mount device to the lands of the printed circuit board.

2. Description of the Related Art [0002] In recent years, semiconductor packages have been downsized and densified in accordance with the tendency to shorten the thickness of electronic products using semiconductor devices. Therefore, in order to reduce the size of semiconductor packages, semiconductor devices have been used in chip- 1, individual chips 110 of the wafer 100 are formed with solder balls (bumps) 112, and a wafer frame (see 130 'in FIG. 2) And is fixed together with the UV-curable tape 120. [

The surface mounting process will be described with reference to FIG. As shown, the individual chips 110 are separated from the wafer frame (see 130 'in FIG. 2) and inverted 110A. This is because when the individual chips are separated from the wafer, the solder ball is upward, but when the surface is mounted on the substrate S, the solder ball 112 must be downward. The solder ball 112 is mounted on the tray T in a downward direction and is held by the picker 300 again from the tray T so that the semiconductor chip is mounted on the land of the substrate.

As described above, the individual chips must be mounted on the substrate by reversing them. Conventionally, the wafer is directly inverted from the wafer surface to be mounted on the substrate. In this case, there is a problem that the equipment investment is high and the tack time is long.

In addition, the flip chip bonding technology is a technology for directly mounting a semiconductor chip on a mounting means by using a bump of conductive material, and it is a conventional technology of wire bonding and a tape automated bonding (TAB) ) Technology, it has an excellent effect in high speed, high integration and miniaturization. In this case, however, there is a problem that an expensive flip chip dedicated facility is required.

On the other hand, individual chips may be separated and then housed in a carrier tape and put into a surface mounting process.

Fig. 4 shows a general carrier tape 200. Fig. As shown in the figure, the carrier tape 200 includes a storage tape 210 having a plurality of pockets 211 capable of housing the semiconductor chips 110 and the like, And the upper surface is sealed with the cover tape 220. [ The carrier tape 200 is rolled in the form of a roll and is transported and supplied to a surface mounting facility.

5 shows a general taping device.

As shown in the drawing, a conventional taping apparatus 10 includes a feeder 13 having guide portions 13a and 13b formed therein to linearly feed a work such as a semiconductor chip, and a workpiece storage portion 12a, 12b, 12 A first and a second inspection means 15 and 16 provided on one side of the index table 11 and a conveying means 17 .

And a sensor for identifying whether or not the work has been transferred to the work storage section.

The first and second inspection means 15 and 16 include inspection portions 15a, 15b, 16a and 16b, respectively, and inspect the work stored in the work storage portion 12 positioned below.

The transfer means 17 is a component for transferring the work determined to be good to the carrier tape 20 through the first and second inspection means 15 and 16 and is provided with transfer portions 17a and 17b .

The carrier tape 20 has a plurality of receiving grooves 21 for receiving a work and a sprocket hole 20 for movement.

And a storage means (not shown) connected to one side of the feeder 13 for storing a work to be processed.

And a drive control unit (not shown) for controlling the inspection means and the conveying means to control the inspection and conveyance of the conveyed workpiece while intermittently rotating the index table when a workpiece is detected by the sensor by the sensor do.

The conventional taping apparatus constructed in this way is also expensive, and there is a problem in that the process time is long considering the taping time.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a semiconductor chip surface mounting method capable of performing a surface mounting process very simply by attaching a thermally debonding tape to a surface of a wafer on which bumps are formed, .

It is another object of the present invention to provide a semiconductor chip surface mounting method in which a semiconductor chip is housed in a tape carrier and a flip chip dedicated facility is not required.

According to an aspect of the present invention, there is provided a method for mounting a surface of a semiconductor chip, including: 1) attaching a UV curable tape to a back surface of a wafer on which bumps are formed; 2) attaching an adhesive tape to the surface of the wafer on which the bumps are formed; 3) inverting the wafer vertically; 4) curing the UV curable tape by irradiating UV; 5) removing the UV curable tape; 6) lowering the adhesive strength of the adhesive tape; And 7) separating the individual chips from the wafer and surface-mounting the chips on the substrate.

Further, it is preferable that the adhesive tape is a thermally releasable tape whose adhesive strength is lowered by applying a predetermined heat.

In the step 6), it is preferable to apply heat to the adhesive tape to lower the adhesive force.

According to the present invention, there is an effect that the surface packaging process can be performed very simply by attaching the heat-peeling tape to the surface of the wafer on which the bumps are formed and reversing.

Therefore, the process of storing the semiconductor chip in the tape carrier and the equipment for exclusive use of the flip chip are unnecessary.

Figure 1 shows a typical wafer.
2 shows a wafer frame.
3 shows a general surface mounting process.
4 shows a general carrier tape.
Figure 5 shows a taping machine.
6 and 7 show a process of separating a semiconductor chip according to the present invention.

Hereinafter, a semiconductor chip surface mounting method according to the present invention will be described in detail with reference to the accompanying drawings.

6 and 7, a method of mounting a semiconductor chip on a surface of a semiconductor chip according to the present invention includes attaching a UV-curing tape 120 to the back surface of a wafer 111 on which bumps of a wafer 111 are formed, (Fig. 6 (a), S10 in Fig. 7).

In a state of being fixed to the wafer frame 130, a gap between individual chips is enlarged by using a known hoop ring. This is because the picker 300 easily adsorbs the individual chips 110.

In this state, an adhesive tape is attached to the surface on which the solder balls (bumps) 112 are formed, as shown in Fig. 6B (S12 in Fig. 7). In this embodiment, it is preferable to use the heat-peeling tape 140 as the adhesive tape. Of course, it is fixed to the wafer frame 130 together with the heat-peelable tape 140 for fixing and transporting the wafer. However, unlike the present embodiment, an adhesive tape other than a thermally releasable tape can be applied to the adhesive tape. For example, it is also possible to use a UV-curable tape as the adhesive tape. In this case, it is preferable that the UV curable tape 120 has a different viscosity or curing condition than the UV curable tape 120 adhered to the back surface of the wafer on which the bumps are formed.

The UV-curable tape 120 is attached to the bottom surface of the wafer 111 and the wafer 110 is vertically inverted with the heat-peeling tape 140 adhered to the top surface (Fig. 6C, S14 in Fig. 7) . That is, the UV-curable tape 120 is positioned on the upper surface of the wafer and the heat-peelable tape 140 is positioned on the bottom surface.

Next, when the UV curable tape 120 is irradiated with UV using the UV lamp 400, the adhesive force is lowered to less than 10% and relatively weaker than the adhesive force of the heat-peelable tape (Fig. 6 (d) , S16 in Fig. 7).

When the UV curable tape 120 and the wafer frame 130 are removed in this state, individual chips in the wafer state are transferred to the heat-peelable tape (Fig. 6 (e), Fig.

Next, in a state of being fixed to the wafer frame 130, a gap between individual chips is once again extended by using a known hoop ring.

Next, the wafer is placed on a hot plate 500 and heated to a predetermined temperature for a predetermined time (FIG. 6 (f), S20 in FIG. 7).

By applying heat, the adhesive force of the heat-peelable tape 140 is lowered to less than 10%.

In this state, individual chips are picked up and transferred to the picker 300, and then individual chips can be surface-mounted on the land P formed on the substrate S (Fig. 6 (h), S22 in Fig. 7 ).

This configuration eliminates the need for complex taping facilities and processes, and allows the semiconductor chip to be surface-mounted simply without a dedicated flip chip facility.

111: wafer
112: Solder ball (bump)
120: UV curable tape
130: Wafer frame
140: Heat-resisting tape
300: Picker
400: UV lamp
500: Hot Plate

Claims

A method of mounting a semiconductor chip having a bump on a printed circuit board,
1) attaching a UV-curing tape to the back surface of the wafer on which bumps are formed;
2) attaching an adhesive tape to the surface of the wafer on which the bumps are formed;
3) inverting the wafer vertically;
4) curing the UV curable tape by irradiating UV;
5) removing the UV curable tape;
6) lowering the adhesive strength of the adhesive tape; And
7) separating individual chips from the wafer and surface-mounting the chips on the substrate,
The pressure-sensitive adhesive tape is a thermally releasable tape having a reduced adhesive strength when a predetermined heat is applied thereto,
In the step (6), heat is applied to the adhesive tape to lower the adhesive force,
Wherein a gap between the individual chips is expanded between the steps 1) and 2).

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