JP2013106026A - Separation device and method of semiconductor wafer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide efficient device and method of separating wafers fixed to a frame therefrom and housing the wafers one by one in a cassette and which, in particular, facilitate cleaning of the wafer.SOLUTION: A wafer group bonded to a frame is disposed while locating the frame above so that the entirety is immersed into the water in a water tank. Adhesive strength of an adhesive at the bonding part of the frame and the wafer is lowered by heating the adhesive, and then the wafer is peeled. The dropping wafer is received in the water tank and transported. Heating of the adhesive is carried out by means of a slit nozzle for ejecting hot-water thus shortening the processing time per wafer.

Description

  The present invention relates to an apparatus and a method for separating a semiconductor wafer used for a solar cell or the like.

A semiconductor wafer is produced by cutting a semiconductor material into a wafer using a wire saw or the like. Immediately after cutting, the edge of the wafer is fixed to the gantry with an adhesive.
Conventionally, the following method has been performed in order to change each wafer into a state where it is stored in a cassette. (1) Immerse the adhesive in the solution and remove the wafer from the mount. (2) Collect and clean the wafers to remove cutting debris and the like. The cleaned wafers are attached to each other in a wet state. (3) Separate the stuck wafers and store them in a cassette. Conventionally, the process (3) has been performed manually by an operator.
Various methods for improving the efficiency by performing the process (3) without human intervention have been proposed. (For example, Patent Documents 1, 2, and 3).

On the other hand, it is more effective to improve the efficiency of the processes (1) to (3) as a whole than to improve the efficiency by separating the process (3). Patent Document 4 discloses a method of separating a wafer from a gantry by a separating means and efficiently storing the wafer in a cassette instead of the process (1). However, the method disclosed in Patent Document 4 separates the wafers one by one from the gantry and drops them toward the storage cassette, and does not perform the cleaning (2). (FIG. 2 and FIG. 5 of Patent Document 4 disclose a state in which a plurality of wafers are accommodated in one cassette. Cleaning in this state is difficult.)
In addition, specific separation means disclosed in Patent Document 4 are those using a blade-like flat plate, those for injecting a solution, and those for cutting a part of the pedestal by laser light. Have. In the case of the blade-shaped flat plate, there is a possibility that the wafer is damaged (wafer cracking or cracking) due to the pressure when the flat plate contacts. In the case of spraying the solution, the remaining solution may be harmful if it is not washed after that. The laser beam equipment for cutting a part of the pedestal with the laser beam is expensive.
As described above, an inexpensive and efficient method and apparatus for separating wafers fixed to a gantry from the gantry and storing them one by one in a cassette, particularly those that are easy to clean the wafer, are known. It was not done.

JP 2011-061121 A JP 2011-044681 A JP 2011-029652 A JP 2010-103417 A

  The problem to be solved is to provide an efficient apparatus and method for separating wafers fixed to a gantry from the gantry and storing them one by one in a cassette.

The semiconductor wafer separation apparatus of the present invention comprises:
A semiconductor wafer separating apparatus for separating each wafer from a group of gantry-bonded wafers whose edges are fixed to the gantry by an adhesive and the wafers are laminated,
A guide device for guiding the gantry bonding wafer group with the gantry up so that the whole is immersed in the water of the aquarium,
Heating and peeling means for heating the adhesive at the bonding portion between the gantry and the wafer to reduce the adhesive force of the adhesive and peeling the wafer;
And a transfer means for receiving and transferring a wafer falling by reducing the adhesive force of the adhesive by the heat peeling in the water tank.
FIG. 1 is a view showing a semiconductor wafer separating apparatus. The gantry bonded wafer group 1 is formed by stacking wafers fixed to the gantry 2, supported by a guide device 3, and controlled in position. The entire gantry bonded wafer group 1 is immersed in water in the water tank 4.
A slit nozzle (hereinafter, abbreviated as “hot water injection slit nozzle”) 5 for injecting hot water heats the adhesive on the first wafer (the wafer on the leftmost side in the figure) of the gantry bonded wafer group 1 to heat the wafer. Is easily peeled off. The roller 6 is for facilitating peeling of the wafer and dropping the peeled wafer directly below. The guide device 3 moves the gantry-bonded wafer group 1 to the left side of the drawing by one wafer every time one wafer falls due to this separation.
The dropped wafers 8 are transferred one by one to the outside of the water tank 4 by the transfer means 7 and stored in a cassette.

The semiconductor wafer separation apparatus of the present invention comprises:
The heating and peeling means is a slit nozzle that simultaneously jets hot water to the entire bonding portion edge of the first wafer among the stacked wafers.
The adhesive strength of the adhesive on the first wafer is lowered to peel the wafer, and the wafer is separated. As the adhesive, an adhesive whose adhesive strength is weakened by heating to 60 ° C. to 90 ° C. may be used. For example, an epoxy or acrylic material may be used.
By using a slit nozzle that jets hot water to the entire edge of the bonded portion of the wafer, the adhesive force of the adhesive on the entire edge can be reduced and the wafer can be separated in a short time. Separation is possible with a processing time of several seconds or less per wafer.
FIG. 2 is a diagram illustrating a method of using the hot water injection slit nozzle. Wafers 8a, 8b,. . . Are laminated and bonded to the gantry 2. The hot water emitted from the slit nozzle 5 is sprayed simultaneously on the entire edge bonded to the gantry 2 at the front wafer 8a, so that the adhesive force of the adhesive on the entire edge is lowered and the wafer is separated in a short time. It becomes possible.
If the wafer does not easily peel off by the above operation, it is also effective as a second best means to apply a slight force to the wafer to promote separation.

The method for separating a semiconductor wafer of the present invention comprises:
A method for separating a semiconductor wafer, in which each wafer is separated from a group of gantry-bonded wafers whose edges are fixed to the gantry by an adhesive and the wafers are laminated,
Place the gantry adhesive wafer group so that the whole is immersed in water in the aquarium,
Heat the adhesive at the bond between the gantry and the wafer,
It is characterized in that the adhesive force of the adhesive is lowered and peeled off by the heating, and the falling wafer is received and transported in the water tank.

  The semiconductor wafer separation apparatus of the present invention provides an efficient apparatus and method for separating wafers fixed to a gantry from the gantry and storing them one by one in a cassette. Since the adhesive is efficiently heated and the wafer is separated from the gantry, the processing time per sheet is short. Further, the wafer stored in the cassette can be easily cleaned.

FIG. 1 is a view showing a semiconductor wafer separating apparatus. FIG. 2 is a diagram illustrating a method of using the hot water injection slit nozzle.

    Example 1 using a hot water jet slit nozzle is shown below.

FIG. 1 is a view showing a semiconductor wafer separating apparatus. The gantry 2 of the gantry bonding wafer group 1 is positioned by the guide device 3. A hot water jet slit nozzle 5 is provided at one end of the guide device 3. An auxiliary roller 6 is provided at a position in contact with the lower part of the top wafer in the gantry bonded wafer group 1 in the water tank 4. The auxiliary roller 6 is made of urethane.
The water tank 4 is filled with water containing a surfactant, and the lower end of the gantry bonded wafer group 1 is immersed in water.
A transfer means 7 (conveyor) is provided at a position for transferring the wafer 8 from below the hot water injection slit nozzle 5 to the outside of the water tank 4.

The guide device 3 is moved by the control means (not shown) to the position where the edge (the upper side in FIG. 2) of the leading wafer 8a of the gantry bonded wafer group 1 receives the hot water from the hot water jet slit nozzle 5.
When hot water is jetted from the hot water jet slit nozzle 5 for a predetermined time, the adhesive force of the adhesive at the edge of the leading wafer 8a is reduced, and the wafer 8a falls. The dropped wafer is transferred out of the water tank 4 by the transfer means 7.
After the fall, the control means moves to a position where the edge of the next wafer 8b receives the hot water from the hot water jet slit nozzle 5.
Here, the time (turnaround) from the time when one wafer moves to a position where the hot water spray slit nozzle 5 receives the hot water jet to the position where the next wafer moves to the position where the hot water jet slit nozzle 5 receives the hot water jet. It is important to shorten the time. A method for this will be described below.

FIG. 2 is a diagram illustrating a method of using the hot water injection slit nozzle.
The hot water sprayed from the rod-shaped hot water spray slit nozzle 5 heats the entire edge where the leading wafer 8a is bonded to the gantry 2 at the same time. As a result, the adhesive on the entire edge is heated in a short time, and the adhesive force is reduced.
As the adhesive, an epoxy or acrylic adhesive whose adhesive strength decreases at 60 ° C. or higher is used.
Wafers can be peeled off in a short time of several seconds or less per wafer.

By rotating the auxiliary roller 6 clockwise in FIG. 1, separation of the wafer 8a from the adjacent wafer 8b is promoted. Since the auxiliary roller 6 is made of urethane, a sufficient frictional force is generated between the auxiliary roller 6 and the wafer to promote separation, and the wafer is not damaged.
As described above, the wafer 8a falls immediately after the adhesive is dissolved.

The dropped wafer is transported in the water tank by the transport means 7. As a result, the wafer is kept in a wet state. Moreover, the cleaning effect by the surfactant in the water tank can be expected.
The dropped wafers are then transferred to the outside of the water tank and stored one by one in a cassette by means not shown.

  The applicant adjusts the position of the hot water jet slit nozzle, the hot water jet amount, and the hot water temperature of the jet so that the bonded portion of the wafer 8a can be heated to 60 to 90 ° C., and selects the adhesive type for several seconds or less. The turnaround time was realized.

  It is an efficient method and apparatus for separating wafers fixed on a gantry from the gantry and storing them one by one in a cassette. The semiconductor wafers, particularly those used for solar cells, can be used by producers. I can expect.

DESCRIPTION OF SYMBOLS 1 Base adhesion wafer group 2 Base 3 Guide apparatus 4 Water tank 5 Hot water injection slit nozzle 6 Auxiliary roller 7 Conveying means 8 Separated wafer

Claims (4)

A semiconductor wafer separating apparatus for separating each wafer from a group of gantry-bonded wafers whose edges are fixed to the gantry by an adhesive and the wafers are laminated,
A guide device for guiding the gantry bonding wafer group with the gantry up so that the whole is immersed in water in a water tank;
Heating means for heating the adhesive at the bonding portion between the gantry and the wafer to reduce the adhesive strength of the adhesive;
A semiconductor wafer separating apparatus, comprising: a transport unit that receives and transports a wafer that falls due to a decrease in adhesive force of the adhesive by the heating unit in the water tank.   2. The semiconductor wafer separation apparatus according to claim 1, wherein the heating and melting means is a slit nozzle that simultaneously sprays hot water over the entire edge of the first wafer among the stacked wafers. A method for separating a semiconductor wafer, in which each wafer is separated from a group of gantry-bonded wafers whose edges are fixed to the gantry by an adhesive and the wafers are laminated,
Place the gantry adhesive wafer group so that the whole is immersed in the water of the aquarium,
Heat the adhesive at the bond between the gantry and the wafer,
A method for separating a semiconductor wafer, wherein a wafer that falls by reducing the adhesive force of the adhesive by heating and melting is received and transported in the water tank.   5. The method of separating a semiconductor wafer according to claim 4, wherein the heating is performed by a slit nozzle that simultaneously jets hot water over the entire edge of the first wafer among the stacked wafers.

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