JPH0249715Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial field of application This invention is used when transferring semiconductor wafers from a wafer process carrier to a wafer boat during high-temperature heat treatment, chemical vapor deposition, etc. in the manufacturing process of semiconductor devices. and a wafer transfer device used when transferring a wafer from a wafer boat to a wafer process carrier.

BACKGROUND TECHNOLOGY AND PROBLEMS Generally, when semiconductor wafers are subjected to high-temperature heat treatment, diffusion, chemical vapor deposition, etc. in the manufacturing process of semiconductor devices, wafer process carriers are used to transport or temporarily store the wafers. The wafers are transferred to a wafer boat made of, for example, quartz that can withstand the furnace that performs this high-temperature heat treatment, diffusion, chemical vapor deposition, etc.; The wafer is transferred to a wafer process carrier. In order to perform this high-temperature heat treatment, diffusion, chemical vapor deposition, etc., the wafers may be pitch-converted and transferred to a wafer boat during the process.

Conventionally, when transferring pitch-converted wafers to a wafer boat in batches, the wafers are stored in a carrier that has been pitch-converted in advance, or the pitch is converted from a process carrier to a buffer carrier using an elevator mechanism, and then the wafers are transferred to a wafer boat. It was being transferred.

Such conventional batch-type pitch conversion is mechanically complex, and wafer transfer devices that do not have a pitch conversion mechanism require additional jigs and tools, resulting in an increase in the number of steps.

Purpose of the invention In view of the above, an object of the present invention is to enable pitch conversion to be performed satisfactorily with a simple configuration.

Summary of the invention This invention is a batch-type wafer transfer device that has a pair of chuck plates for wafer handling that can be opened and closed. and the plurality of grooves are arranged so that when the pair of chuck plates are closed, the distance between the troughs at the tips of the corresponding grooves of the pair of chuck plates is smaller than the diameter of the wafer, and the wafer is The distance between the first groove that can be captured and the trough at the tip of the corresponding groove of the pair of chuck plates when the pair of chuck plates is closed is larger than the diameter of the wafer, and the wafer is The first groove and the second groove are provided at a constant ratio and at a constant interval to facilitate pitch conversion of the wafer when transferring the wafer. According to the present invention, pitch conversion can be performed satisfactorily during wafer transfer with a simple configuration.

Embodiment An embodiment of the wafer transfer apparatus of the present invention will be described below with reference to the drawings.

FIG. 1 shows the main parts of a wafer transfer device installed in a heat treatment furnace for semiconductor wafers, for example, 1 is the main body of the wafer transfer device; It is configured to be disposed on a wafer boat 2 and a wafer process carrier 3. The wafer boat 2 in this example has three support rods 2a fixed by a fixing frame 2b, and the wafer boat 2 is designed to support an approximately 90° angle range of the approximately circular semiconductor wafer 4. The wafer boat 2 is configured such that, for example, 100 semiconductor wafers 4 can be placed on a 3/32 inch pitch. Further, this wafer process carrier 3 is constructed so as to be able to accommodate, for example, 25 semiconductor wafers 4 at a pitch of 3/16 inch.

In FIG. 1, reference numeral 5 indicates a wafer handling device, and this wafer handling device 5 is configured to be able to automatically move in the X-axis, Y-axis, and Z-axis directions over a predetermined range according to an operation.

As shown in FIGS. 2 and 3, this wafer handling device 5 consists of a pair of chuck plates 5a and 5b each having a plurality of, for example, 50 vertical grooves 6 with a pitch of 3/32 inch in the lower portions of opposing surfaces. The pair of chuck plates 5a and 5b are configured to be openable and closable in opposite directions by a well-known parallel opening and closing mechanism.
In this case, when the pair of chuck plates 5a and 5b are closed, the side edges of the wafer 4 are held between every other opposing vertical groove 6a of the 50 vertical grooves 6, and the other vertical grooves The groove 6b is configured so that it cannot capture the wafer 4 at this time.

In this example, every other vertical groove 6a of the pair of chuck plates 5a and 5b is formed along the inward curvature of the tips of the chuck plates 5a and 5b, as shown in FIGS. 2 and 4. Like, this chalkboard 5
Vertical groove 6a when a and 5b hold the wafer 4
For example, if the diameter of the wafer 4 is the curvature of the valley 6ab of
If the radius is 50mm when the wafer is 100mm, then this wafer 4
It is assumed that the curvature is the same as that of the trough 6ab of each vertical groove 6a of the chuck plates 5a and 5b.
The centers of curvature of each of the wafers 4 and 4 are arranged so that they are slightly closer to the center of the wafer 4. In addition, the remaining vertical grooves 6b of the vertical grooves 6 are formed so that their troughs 6bb are linear without following the curves of the tips of the chuck plates 5a and 5b, as shown in FIGS. 3 and 4. Even when the grooves 5a and 5b are in the closed state, the distance between the valleys 6bb and 6bb of the vertical grooves 6b and 6b facing each other is configured such that the diameter of the wafer 4 is, for example, 104 mm, which is larger than 100 mm.

Furthermore, the radius of the curvature of the crest 6t of the vertical groove 6 is 53 mm, which is approximately the same as the curvature of the wafer 4, and the curvature of the ridge 6t of each of the chuck plates 5a and 5b is set to 53 mm.
The centers of curvature of each of t and 6t are on this wafer 4.
chuck plates 5b and 5a slightly opposite to each other from the center of the
Place the chuck plates 5a and 5 so that they are on the side.
Center of curvature 7 of each peak 6t and 6t of b
b is positioned above the center of curvature 7a of the vertical grooves 6a and 6a. Furthermore, in this case, the distance between the uncurved portions of the chuck plates 5a and 5b when the chuck plates 5a and 5b are in the closed state is set to 104 mm, which is slightly larger than the diameter of the wafer 3, for example, 100 mm, and the vertical grooves of each of the chuck plates 5a and 5b are 6a valley 6ab
For example, 9mm from the inner tip of this non-curved part.
Make it stand out. Further, in this example, the longitudinal grooves 6a, 6b of the chuck plates 5a, 5b are
The widths of ab and 6bb are set to 0.8 mm, which is slightly larger than the thickness of the wafer 4, for example, 0.5 mm, and a V-groove is formed that widens on both sides at an angle of 9 degrees from this.

Since this example is configured as described above, the wafer process carrier 3 is housed with a 3/16 inch pitch.
When transferring a plurality of, for example, 25 semiconductor wafers 4 to the wafer boat 2 at a pitch of 3/16 inches,
The wafer handling device 5 is brought over and approached the process carrier 3 placed at a predetermined position, and the chuck plates 5a and 5b are opened, and every other vertical groove 6a is inserted into the semiconductor wafer 3.
In the closed state, the 25 semiconductor wafers 4 are held between the chuck plates 5a and 5b, and in this state, the wafer handling device 5 is placed on a predetermined position of the wafer boat 2, which is placed in a predetermined position. Then, with the wafer 4 held between the chuck plates 5a and 5b, insert it into every other groove, that is, at a 3/16 inch pitch, in the support rod 2a of the wafer boat 2, and then press the chuck plate 5a. , 5b is opened, and this wafer 4 is transferred.

Further, when transferring semiconductor wafers 4 that have been subjected to high-temperature heat treatment etc. from the wafer boat 2 to the wafer process carrier 3, the wafers 4 placed on the wafer boat 2 are transferred by chuck plates 5a and 5b of the wafer handling device 5 in the same manner as described above. holding the
In this state, the wafer handling device is brought onto the process carrier 3, and the wafer 4 is transferred onto the process carrier 3.

Next, when transferring the semiconductor wafers 4 of the wafer process carrier 3 stored in this 3/16-inch pitch to the wafer boat 2 with this 1/2-inch pitch, which is 3/32-inch pitch, the first time is the same as described above. The semiconductor wafers 4 are transferred to the wafer boat 2 at a pitch of 3/16 inch, and then the semiconductor wafers 4 from another wafer process carrier 3 are transferred to the chuck plates 5a and 5b of this wafer handling device 5.
The wafer 4 was held in the same manner as described above, and the wafer handling device 5 was brought onto the wafer boat 2 in this state.
Wafer boat 2 with a 32 inch pitch shift
Transfer it close to. In this case, the wafers 4 transferred for the first time correspond to the vertical grooves 6b of the chuck plates 5a and 5b, so that they can be transferred without any problem and are transferred at a pitch of 3/32 inch.

Also, when storing the wafers 4 of the wafer boat 2 transferred to this 3/32 inch pitch into the 3/16 inch pitch wafer process carrier 3, the first
In the first transfer, every other wafer 4 is transferred while being held between the chuck plates 5a and 5b, and then the wafers 4 on the remaining wafer boats 2 are transferred in the same manner as described above.

Next, in the above embodiment, when it is desired to place the wafers 4 on the wafer boat 2 at a pitch of 3/8 inches, which is twice the pitch of 3/16 inches, the pitch of the vertical grooves 6 of the chuck plates 5a and 5b is set to a pitch of 3/16 inches. Similarly to the above, every other vertical groove 6a and 6
The configuration b may be used. In this case, every other wafer 4 is clamped from the wafer process carrier 3 by the chuck plates 5a and 5b of the wafer handling device 5, transferred to the wafer boat 2 in this state, and then transferred to the wafer process carrier 3. If the wafer 4 is sandwiched between the chuck plates 5a and 5b with a 3/16 inch pitch shift and is placed successively on the wafer 4 previously placed on the wafer boat 2 in this state, the wafer 4 will be placed at a 3/8 inch pitch. It can be transferred to the wafer boat 2. When storing wafers 4 from the 3/8 inch pitch wafer boat 2 into the 3/16 inch pitch wafer process carrier 3, first transfer the wafers 4 at a 3/8 inch pitch in the same manner as described above, and then transfer the remaining 3/8 The wafers 4 held between the chuck plates 5a and 5b at an inch pitch are stored in the wafer process carrier 3 with a pitch shifted by 3/16 inch from the previous time.

In this case, if the grooves 6a and 6b of the above-mentioned structure are provided in the chuck plates 5a and 5b of the wafer handling device 5 at a constant ratio and at a constant interval as described above, the desired pitch can be changed when transferring the wafer 4. can.

It goes without saying that the present invention is not limited to the above-described embodiments, and that various other configurations may be adopted without departing from the gist of the present invention.

Effects of the Invention According to the present invention, pitch conversion can be performed satisfactorily when transferring wafers 4 by simply changing the structure of chuck plates 5a and 5b of wafer handling device 5. Further, according to the present invention, there is an advantage that a complicated mechanism for pitch conversion and a pitch conversion jig are not required. Further, since the present invention has a simple structure as described above, the transfer device is inexpensive, and the reliability of pitch conversion during wafer transfer is improved, and maintainability is also improved.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway perspective view showing an embodiment of the wafer transfer device of the present invention, FIGS. 2 and 3 are cross-sectional views showing examples of the main parts of the present invention, and FIG. FIG. 3 is an enlarged cutaway diagram showing an example of a main part. 1 is a wafer transfer device main body, 2 is a wafer boat, 3 is a wafer process carrier, 4 is a semiconductor wafer, 5 is a wafer handling device, 5a
and 5b are chuck plates, 6a and 6b are longitudinal grooves, 6ab and 6bb are valleys of the longitudinal grooves, and 6t are peaks of the longitudinal grooves.

Claims (1)

[Scope of utility model registration request] In a batch-type wafer transfer device having a pair of chuck plates for wafer handling that can be opened and closed, the chuck plate has grooves wider than the thickness of a plurality of wafers at equal intervals on the inside, and The grooves are formed such that when the pair of chuck plates are closed, the distance between the troughs at the tips of the corresponding grooves of the pair of chuck plates is smaller than the diameter of the wafer, and the center of curvature of the peaks of the pair of chuck plates is is a first groove capable of capturing the wafer, which is located above the center of curvature of the trough at the tip of the corresponding groove of the pair of chuck plates; The gap between the troughs at the tips of the corresponding grooves is larger than the diameter of the wafer, and a second groove cannot capture the wafer,
A wafer transfer device characterized in that the first groove and the second groove are provided at a constant ratio and at a constant interval to facilitate pitch conversion of the wafer during wafer transfer.