JP2001118908A - Wafer transfer equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To offer a wafer transfer equipment which enables the transfer of wafers to a cassette without causing cracks in the wafers even if there is produced a disaccord between a pitch of the substrate placed on a lift and a pitch of a chuck part. SOLUTION: A wafer transfer equipment in a semiconductor manufacture process comprises a lift 5 for taking out wafers from cassettes 2a and 2b while placing the wafers on it, and a chuck part 6 for holding the wafers above the cassettes 2a and 2b. The lift 5 consists of a elevating member 4 comprising a part 3 where the wafers are placed on its upper end, the part 3 can be separated from the elevating member 4, and additionally the chuck part 6 grasps the part 3 to hold the wafer 1 above.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a substrate transfer device. More specifically, the present invention relates to a substrate transfer apparatus that lifts and takes out a substrate (semiconductor wafer) in a cassette and stores it in another cassette.

[0002]

2. Description of the Related Art In a semiconductor manufacturing process, a substrate such as a semiconductor wafer is accommodated in a cassette and transported, and is transferred from a cassette transported for each manufacturing process to another cassette used in the process. Processing is performed.

FIG. 4 is a schematic view sequentially showing a method of using a conventional substrate transfer apparatus. Cassette 3 containing substrate 31
2a and an empty cassette 32b are set in the substrate transfer device. Below these cassettes 32a and 32b, there is provided a lift 35 composed of an elevating member 34 having a substrate mounting portion 33 at its upper end. A chuck 36 for holding the substrate 31 is provided above the cassettes 32a and 32b. Each of the cassettes 32a and 32b is a frame body whose top and bottom surfaces are open. For example, twenty-five substrates 31 can be housed side by side between the side plates perpendicular to the drawing.

[0004] The lift 35 is inserted into the cassette and moves up and down. The substrates in the cassette are all placed on the substrate mounting portion 33 at the same time as the lift 35 rises, and are held by the chuck portion 36 at the raised position. The chuck portion 36 is provided with grooves (not shown) having a constant pitch arranged in the vertical direction in the drawing corresponding to the pitch of the 25 substrates 31 accommodated in the cassettes 32a and 32b.

As shown in FIG. 1A, the cassettes 32a and 32b set in the substrate transfer device are slid in the direction of the arrow q to a lift position where the lift 35 is disposed immediately below the cassette 32a.

Next, as shown in FIG. 2B, with the cassette 32a stopped at this lift position, the lift 35 is
In the direction, and all the substrates 31 in the cassette are placed on a substrate mounting portion (lift claw) having substrate locking claws 33a on both sides.
33. Further, the lift 35 is connected to the cassette 32a.
To lift the substrate 31 out of the cassette 32a.

Next, as shown in FIG. 1C, when the lift 35 on which the substrate 31 is placed is raised to a predetermined upper position, the lift 35 stops. At this position, the chuck portion 36 moves in the direction of the arrow s, sandwiches the substrate 31 from both sides, and holds each substrate engaged with each groove of the chuck portion 36. When the chuck portion 36 holds the substrate 31, the substrate 31
The lift 35 holds the substrate mounting portion 3 while holding the
3 and descends in the direction of arrow t.

Next, as shown in FIG. 3D, in a state where the lowering of the lift 35 is completed and the cassette 32a and 32b are located below the cassette, the cassettes
2b is arranged at the lift position. Thereafter, the lift 35 is raised, penetrates the cassette 32b, and is raised to the chuck position.

Next, as shown in FIG.
Is moved in the direction of the arrow x to release the holding of the substrate, and the substrate 31 held by the chuck portion 36 is placed on the substrate placing portion 33 of the lift 35. The lift 35 on which the substrate 31 is placed descends in the direction of arrow y, and the substrate 31
To store.

As a result, as shown in FIG.
The transfer from the cassette 32a to the cassette 32b is completed. Thereafter, the cassette 32b is transported to the next process position.

[0011]

However, when the chuck itself holds the substrate itself so as to be directly sandwiched between the chucks as in the conventional substrate transfer apparatus, the 25 substrates mounted on the substrate mounting portion of the lift at a constant pitch are used. If at least one of the substrates is displaced from the groove at a position deviated from the pitch of the chuck portion, a large pinching force acts on the substrate to cause cracking of the substrate.
When the substrate cracks, the broken pieces affect the surrounding substrates. In addition, since the substrate is held in direct contact with the substrate itself, the substrate is easily scratched.

The present invention has been made in consideration of the above-mentioned prior art, and suppresses scratches on a substrate taken out of a cassette and mounted on a lift, and a pitch of the substrate and a chuck for holding the substrate above the cassette. It is an object of the present invention to provide a substrate transfer apparatus that can transfer a substrate to a cassette without causing a substrate crack even when a mismatch occurs between the pitch of the substrate and the unit.

[0013]

In order to achieve the above object, according to the present invention, in a semiconductor manufacturing process, a lift for placing and taking out a substrate from a cassette and holding the taken out substrate above the cassette. In a substrate transfer device having a chuck portion, wherein the lift includes an elevating member having a substrate mounting portion at an upper end, the substrate mounting portion is separable from the elevating member, and the chuck portion includes a substrate mounting portion. Provided is a substrate transfer device characterized by holding a substrate upward by holding a mounting portion.

According to this structure, the chuck holds the substrate mounting portion that can be separated from the elevating member and holds the substrate mounting portion together with the substrate above the cassette in a state where the substrate mounting portion is separated from the elevating member. Not directly held by the chuck,
Does not receive pinching force from the chuck. Therefore, even if the substrate on the substrate mounting portion is displaced from the pitch of the chuck portion with respect to the substrate, the substrate does not crack.

In a preferred embodiment, positioning and fixing means comprising a projection and a recess which are fitted between the chuck portion and the substrate mounting portion and between the substrate mounting portion and the elevating member are provided. It is characterized by.

According to this configuration, the chuck portion and the substrate mounting portion can be securely connected to each other, and can be accurately fixed at a predetermined fixed position, and the same can be applied between the substrate mounting portion and the elevating member. Can be reliably fixed at the connection position, so that positional deviation due to separation from each other can be prevented.

In a preferred configuration example, a vacuum suction means for holding the substrate mounting portion on an elevating member is provided.

According to this configuration, the substrate placing portion and the elevating member can be more securely and closely connected to each other, and the substrate placing portion is securely fixed and held without falling off from the upper end of the elevating member.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram showing in order a method of using a substrate transfer device according to the present invention. A cassette 2a containing one lot (for example, 25) substrates (semiconductor wafers) 1 (only one is shown in the figure) and an empty cassette 2b are set in the substrate transfer device. Cassette 2a,
Below 2b, there is provided a lift 5 composed of a lifting member 4 having a substrate mounting portion 3 at its upper end. These cassettes 2a,
Above 2b, a chuck unit 6 for holding the substrate mounting unit 3 is provided. Each of the cassettes 2a and 2b is a frame body whose top and bottom surfaces are open. For example, twenty-five substrates 1 can be housed side by side between side plates perpendicular to the drawing. The lift 5 moves up and down by passing through the cassette.

As shown in FIG. 1A, the cassettes 2a and 2b set in the substrate transfer device are slid in the direction of arrow q to a lift position where the lift 5 is disposed immediately below the cassette 2a.

Next, as shown in FIG. 2B, with the cassette 2a stopped at this lift position, the lift 5 is raised in the direction of arrow r, and all the substrates 1 in the cassette are held on both sides by the substrate locking means. It is placed on a substrate placing section (lift pawl) 3 having claws 3a. Further, the lift 5 is raised by penetrating the cassette 2a, and the substrate 1 is lifted and taken out of the cassette 2a. At this time, the substrates 1 in the cassette are all placed on the substrate placing portion 3 at the same time as the lift 5 is raised.

Next, as shown in FIG. 2C, when the lift 5 on which the substrate 1 is placed is raised to a predetermined upper position, the lift 5
Rise stops. At this position, the chuck unit 6 moves in the direction of the arrow s, and holds the substrate mounting unit 3 on which the substrate 1 is mounted, sandwiching the substrate mounting unit 3 from both sides. The substrate mounting part 3 and the elevating member 4 are separable, and when the chuck part 6 holds the substrate mounting part 3, the elevating member of the lift 5 is held in a state where the substrate mounting part 3 is held upward together with the substrate 1. Only the substrate 4 separates from the substrate mounting part 3 and descends.

Next, as shown in (D), when the elevating member 4 is lowered to the lower side of the cassette, the cassettes 2a and 2b are slid in the direction of arrow w so that the cassette 2b is located at the lift position. Thereafter, the elevating member 4 is raised, penetrates the cassette 2b, and is raised to the chuck position. Here, the elevating member 4 is coupled to the substrate mounting portion 3 held by the chuck 6.

Next, as shown in FIG.
Is moved in the direction of the arrow x to release the holding of the substrate mounting portion 3. Subsequently, in a state where the substrate placing portion 3 on which the substrate 1 is placed and the elevating member 4 are connected, the lift 5 descends in the direction of the arrow y, and stores the substrate 1 in the cassette 2b.

This completes the transfer of the substrate 1 from the cassette 2a to the cassette 2b, as shown in FIG. Thereafter, the cassette 2b containing the substrates 1 is transported to the next process position.

FIG. 2 is a detailed view of a main part of the substrate transfer apparatus according to the present invention. As shown, a projection 7 is provided at the tip of the elevating member 4, and the substrate mounting portion 3 is provided with a recess 8 into which the projection 7 fits. Similarly, a projection 7 and a recess 8 are provided on the joint surface between the chuck section 6 and the substrate mounting section 3.

As a result, the chuck section 6 is moved to the substrate placing section 3.
When gripping and holding the substrate, the chuck portion securely holds the substrate mounting portion at a fixed position without causing a positional shift.
Therefore, the elevating member that moves up and down at a certain position is securely aligned and connected to the substrate mounting portion. Also,
Similarly, since the lifting member and the substrate mounting portion can be securely fixed at the connection position, it is possible to prevent a positional shift due to separation from each other.

FIGS. 3A and 3B are schematic views of the lifting member of the lift according to the present invention, wherein FIG. 3A is a top view and FIG. 3B is a side view. As shown in the drawing, the upper surface of the elevating member 4 (the substrate
And two projections 7 are formed on
An O-ring 10 is mounted along the outer peripheral edge. Inside the O-ring 10, a plurality of vacuum holes 9 communicating with a vacuum device (not shown) are provided. By performing vacuum evacuation through these vacuum holes 9, the substrate mounting portion 3 bonded to the upper surface is vacuum-sucked, and the substrate mounting portion 3 is securely placed on the elevating member.
Can be fixedly held. In this case, it is desirable to provide a vacuum sensor, connect it to the lift drive device, and provide an interlock so that the lift does not operate unless the vacuum pressure exceeds a set value.

[0029]

As described above, according to the present invention, the chuck portion for holding the wafer upward during the movement of the cassette grasps the substrate mounting portion which can be separated from the elevating member,
Since the substrate mounting portion is held together with the substrate (wafer) above the cassette in a state where the substrate mounting portion is separated from the elevating member, the substrate is not directly clamped by the chuck portion and does not receive a pinching force from the chuck portion. Therefore, even if the substrate on the substrate mounting portion is displaced from the pitch of the chuck portion with respect to the substrate, the substrate does not crack. As a result, the wafer can be smoothly transferred while being mounted on the substrate mounting portion, and there is no scratch on the wafer because it is not in contact with the wafer. In addition, since scratches are not formed, it is not necessary to regenerate a resist or the like. Also, cracks due to the pinching force of the chuck are eliminated, dust and the like are suppressed, yield is improved, and troubles of the transfer device and the transport device due to cracks are reduced, and man-hours for dealing with this are reduced. As a result, the operation rate and the productivity are improved.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view sequentially showing a method of using a substrate transfer device according to the present invention.

FIG. 2 is a main part configuration diagram of a substrate transfer device according to the present invention.

FIG. 3 is a schematic configuration diagram of a lifting member.

FIG. 4 is a schematic explanatory view sequentially showing a method of using the conventional substrate transfer device.

[Explanation of symbols]

1: substrate, 2a, 2b: cassette, 3: substrate mounting portion,
4: lifting member, 5: lift, 6, chuck, 7: projection, 8: recess, 9: vacuum hole, 10: O-ring

Claims (3)

[Claims] 1. A semiconductor manufacturing process comprising: a lift for mounting and removing a substrate from a cassette; and a chuck unit for holding the extracted substrate above the cassette, wherein the lift has a substrate mounting unit at an upper end. In the substrate transfer device including the elevating member having: the substrate mounting portion is separable from the elevating member, and the chuck portion grasps and holds the substrate mounting portion separated from the elevating member upward. A substrate transfer device characterized by the above-mentioned. 2. A positioning and fixing means comprising a projection and a recess which are fitted to each other between said chuck portion and said substrate mounting portion and between said substrate mounting portion and said elevating member. The substrate transfer device according to claim 1. 3. The substrate transfer apparatus according to claim 1, further comprising vacuum suction means for holding said substrate mounting portion on an elevating member.