JP2757664B2 - Die pickup method and collet - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an assembling method for assembling an elongated die such as a one-dimensional CCD line sensor, and more particularly to a die pickup method and a collet for picking up a die from a wafer sheet.

[0002]

2. Description of the Related Art Generally, a die pick-up is performed by individually positioning dies obtained by dividing a wafer stuck on a wafer sheet, holding the dies by suction with a collet, and pushing up from the lower side of the wafer sheet. Push up with a needle,
The die is peeled off from the sheet and transferred.

The collets used here are roughly classified into two types. One is a surface collet that contacts the die surface and sucks and holds the die, and the other is a taper part that is provided corresponding to two or four opposite sides of the die and contacts the edge of the die. A two-sided or four-sided (pyramidal) collet (hereinafter referred to as a tapered collet) that holds a die by suction.

Conventionally, in a one-dimensional CCD line sensor, light receiving portions are arranged on a die surface, and unlike other semiconductor elements such as a memory, a passivation film is not formed on the surface, so that wiring is exposed. However, there is a problem that the collet cannot adsorb the surface, and a tapered collet is used for the pickup.

In addition, at the time of picking up, the tapered portion of the collet needs to enter the gap between the dies so that the die is held by the tapered portion of the collet. When the wafer sheet is stretched, the distance between the dies is reduced. Of 25
Work to enlarge the size from about 70 μm to 200 to 400 μm was also performed.

[0006]

Recently, one-dimensional CCD line sensors have become longer and thinner in order to improve manufacturing technology and yield per wafer. For example, in the case of mass production, 0.65 mm wide x 35 mm long x
0.4mm thick, 0.8mm wide for those currently under consideration for commercialization
mm × length 80 mm × thickness 0.4 mm.

Therefore, when a die is picked up from a wafer sheet, the taper collet is used, so that the die, which is one of the conventional purposes of using the taper collet, slides at the tapered portion, the position of the die can be corrected, and the pickup can be stably performed. On the other hand, the advantage of being able to do so is that the die is slippery and rotates due to the narrow width of the die, so that it cannot be picked up stably.

Further, even if an area for contacting the surface collet is simply provided and the surface collet is used, if the area is provided on the short side, the width of the die is increased (for example, 400 mm per side).
If an area of μm is provided, the width will be 0.65mm → 1.45m
m, width 0.8 mm → 1.6 mm) The yield per die of the die is drastically reduced. Therefore, if the area is provided on the long side, the yield is almost the same, but since the die is thin and the strength is weak, the die is greatly deformed when picking up,
There is a problem that the light receiving portion of the die contacts the collet and causes a flaw.

SUMMARY OF THE INVENTION An object of the present invention is to provide a die pickup method and a collet for stably picking up a die which cannot be brought into direct contact with the surface, such as a one-dimensional CCD line sensor, from a wafer sheet.

[0010]

In order to achieve the above object, a die pickup method according to the present invention is a die pickup method for individually picking up an elongated die from a wafer sheet. A suction area in which a region is formed is provided, a collet is brought into contact with only this area, and a die is held and picked up.

In the above-mentioned suction area, wiring which becomes unnecessary after assembling the semiconductor device, such as a registration pattern and a wiring for inspection, is provided.

Further, the collet according to the present invention is a collet used for a die pick-up method for individually picking up an elongated die from a wafer sheet. And a tapered portion for receiving the edge of the central portion with a tapered surface when the central portion of the die rises due to the deformation of the die.

[0013]

A suction area of 400 μm or more is provided at both ends in the longitudinal direction of the die surface, and only the area is held in contact with a surface collet. When the die is deformed, the edge of the die is received by the tapered portion of the collet.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings.

(Embodiment 1) FIG. 1 is a sectional view showing a die pickup state in Embodiment 1 of the present invention.

In FIG. 1, a die 1 has four
It has a contact area of 00 μm, is affixed to the wafer sheet 3 and is individually divided, and is positioned at the pickup position by a wafer sheet holding ring and a die positioning mechanism (not shown).

A plurality of push-up needles 5 that push up the center of the short side of the die 1 are arranged in the direction of the long side of the die, are held by a needle holder 6, and are controlled to operate in synchronization with the collet 2. ing.

The sheet suction holders 4a and 4b hold the push-up needle 5 and the needle holder 6 in a vertically movable state, and are connected to a suction device so that the wafer sheet 3 can be suction-held by vacuum suction.

The collet 2 is 400 μm on each end of the die 1.
Corresponding to the contact area of the contact portion 2b,
The die 1 is sucked and held by the vacuum suction hole 2a provided in the nozzle b.

The collet 2 is provided with a relief 2c so that the collet 2 does not come into contact with the die 1 even if the die 1 is deformed into an arc shape during pickup. It is known that this clearance may be about 0.4 mm to 0.5 mm at the center based on the strength and deformation of the die.

Next, the pickup method will be described step by step. The die 1 is positioned at the pickup position, and the wafer sheet 3 is suction-held by the sheet suction holders 4a and 4b.

Thereafter, the collet 2 is moved, brought into contact with the die 1, and held by suction.

The collet 2 and the push-up needle 5, that is, the needle holder 6 are raised in synchronization with each other, and the die 1 is peeled off from the wafer sheet 3. At this time, the wafer sheet 3 is held by suction by the sheet suction holder.
In this case, only the portion where the push-up operation is performed is deformed, and the die 1 is supported at points, which has an effect that the die 1 is easily peeled off from the wafer sheet 3.

Here, contact areas at both ends of the die 1 include:
Circuits and wiring that become unnecessary after assembling as a semiconductor device, such as a pattern for alignment and a circuit for measuring electrical characteristics,
Providing a conventional arrangement in a die has the advantage that the contact area can be provided without substantially changing the size of the die.

In addition, the use of the surface collet eliminates the rotation of the die and allows stable pick-up.
There is no need to provide an interval like m, and there is an advantage that the work of expanding the sheet can be omitted.

(Embodiment 2) FIG. 2 is a sectional view of a collet used in Embodiment 2 of the present invention.

The collet 2 'has a contact portion 2'b and a vacuum suction hole 2'a, and also has a tapered portion 2'c at the center in the longitudinal direction. The edge of the die can be captured at 'c.

In this case, no escape is required on the lower surface of the collet, and the collet can be made flat, so that a plurality of vacuum suction holes for die suction can be provided in the longitudinal direction of the die. There is an advantage that it can be strengthened.

Further, the tapered portion 2'c does not need to be in contact with the die at the time of pickup, and may be provided above the die surface (preferably about 0.2 mm above), so that it can be used in the same manner as a surface collet. As in the first embodiment, sheet enlargement is not required.

[0030]

As described above, according to the present invention, the contact area of 400 μm or more is provided at both ends in the longitudinal direction of the die. It can be used and has an effect that it can be stably picked up.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a state of a die pickup according to a first embodiment of the present invention.

FIG. 2A is a sectional view showing a collet used in a second embodiment of the present invention, and FIG. 2B is a sectional view taken along the line BB ′ of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Die 2, 2 'collet 2a, 2'a Vacuum suction hole 2b, 2'b Contact part 2c Relief 2'c taper part 3 Wafer sheet 4a, 4b Sheet suction holder 5 Push-up needle 6 Needle holder

Claims (3)

(57) [Claims] 1. A die pick-up method for individually picking up an elongated die from a wafer sheet, wherein a suction area having an active area formed at both ends in a longitudinal direction of a die surface is provided, and a collet is brought into contact only with the area. A die pick-up method characterized by holding and picking up. 2. The die pickup method according to claim 1, wherein wiring that becomes unnecessary after assembling the semiconductor device, such as an alignment pattern and a wiring for inspection, is provided in the suction area. 3. A collet used in a die pick-up method for individually picking up an elongated die from a wafer sheet, wherein the collet has a portion for contacting and holding suction areas at both ends of the die and a die center portion due to die deformation at the time of pickup. A collet having a tapered portion that receives a central edge with a tapered surface when the bulges.