JPH0648851Y2 - Wafer changer - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a wafer changer for transferring wafers between carriers and boats, which is used in a wafer processing process in semiconductor device manufacturing.

Conventional technology Conventionally, as a semiconductor wafer transfer machine,
What is called a batch type money-return machine as shown in the figure is generally used. That is, in FIG. 4, when transferring from a carrier 2 in which a large number of wafers 1 are arranged upright to, for example, a boat 3 for heat treatment, the carrier is moved to the replacement position A in advance, and the carrier is moved from below the position. ,
The pusher 4 is pushed up, and only the wafer 1 is taken in and retracted to the holder 5 standing by above B. Then, the empty carrier 2 is returned to the original position D, and this time the empty boat 3 is transferred to the replacement position A and made to stand by, and the pusher is again pushed to the holder 5 in which the wafer 1 is taken in and retracted. 4 is pulled up, the wafer 1 is received, and it is descended and transferred to the boat 3. After that, the boat 3 on which the wafer has been mounted is returned to the original position C.

Problems to be Solved by the Invention By the way, a holder 5 for taking in and retracting the wafer 1
As shown in FIG. 5, vertical taper grooves 6, 6 ... Are provided in order to keep the wafer 1 at a predetermined pitch. However, there are the following problems. That is, the wafer 1
A soft metal such as Al or a material such as a photoresist that is easily peeled off is attached to the surface of the. Therefore, when the pusher 4 receives the wafer 1 from the lower side and moves it up and down for wafer attachment / detachment, the holders 5 and 5 are stationary at this time, so that the peripheral edge of the wafer 1 and the groove 6 are The inner surface 6i causes sliding friction, and soft metal, photoresist, etc. are generated as fine powdered dust.

This problem is inferred from the above description, but the pusher 4 not only limited to the holder 5 but also pushes up the wafer 1 from below or receives and lowers and transfers the wafer 1 held by the holder 5 is shown in FIG. As shown in the drawing, since the holding groove 4a for supporting the wafer 1 is provided, there is a problem that dust is generated / attached / accumulated in the groove. Means for Solving the Problems The present invention aims to solve the above problems. Is what you propose,
Set the wafer holding groove pitch of the pusher and holder to
As an integer fraction of the holding groove pitch of the carrier or holder, when storing the wafer in the holder from the pusher, when receiving the wafer from the holder to the pusher, when transferring from the carrier to the boat, and from the boat to the carrier In order to make it possible to select and change the holding groove to be used in a process such as when transferring, the pusher and the holder are slightly moved so as to be displaced by one to several pitches.

The present invention provides that the pusher and the holder use, for example, even-numbered holding grooves from one end when the wafer is pushed up by the pusher and temporarily stored in the holder by providing the means for solving the above problems. Then, when the holder is supported by the pusher and taken out, and when it is transferred to another carrier or a boat, it can be selectively made different by using an odd-numbered holding groove with a gap of one pitch.

Therefore, when the wafer is taken out of the holder and transferred, the probability that dust adheres or accumulates is significantly reduced.

Embodiment FIG. 1 is a perspective view showing a holder and a pusher of a wafer sorter showing an embodiment of the present invention, and the same reference numerals as those in the conventional example shown in FIGS. 4 to 6 are the same. In this embodiment, the structure is different from the conventional case in that the indenting drive units 10b and 11b are arranged in the wafer alignment pitch interval direction, that is, in the arrow 10a and 11a directions in the drive units 10 and 11 of the holder 5 and pusher 4.
Is provided. This inching drive unit 10b, 11b
As a specific mechanism, as shown in FIG. 2, it is possible to perform positioning that exactly matches the wafer alignment pitch interval, that is, the interval between the taper groove 6 of the holder 5 and the holding groove 4a of the pusher 4. Plates 10c, 11c with rack teeth formed at wafer alignment pitch intervals as required
The pinion gears 10d and 11d which are driven by a motor and mesh with the rack teeth are suitable. Further, the pitch interval P between the taper groove 6 and the holding groove 4a is set to 1/2 of the pitch interval Pc of the wafer carrier 9 shown in FIG. 3, for example. In other words, the number of pitches of the taper groove 6 and the holding groove 4a is twice the number of pitches of the holding groove 9a of the carrier 9.

When the wafer 1 is pushed up from the carrier 9 to the holder 5 by the pusher 4 and stored in the above-mentioned wafer sorter,
A group of grooves in which the holding groove 4a of the pusher 4 is an odd number from one end side
The wafer 4 is positioned so that the wafer 1 is pushed up and taken out.
Therefore, by positioning the holder 5 in the same manner, the holder 5 can be housed in the odd-numbered taper groove group 6.
Then, when the wafer 1 is taken out from the holder 5 and is received by another carrier or a boat, the holding groove group 4a of the pusher 4 is designated as an even number this time. In this case, the empty holder 5 that has been received uses the even number when returning the taper groove group 6 to the original carrier even if the taper groove group 6 is changed to the even number at this point.

As described above, in this embodiment, the wafer 1 is held by the holder 5
Since the holding groove 4a and the taper groove 6 of the pusher and the holder are used differently when storing and receiving, the probability that dust adheres to and accumulates in the groove is 50
It can be reduced to about%.

In the above embodiment, the wafer holding groove pitch of the pusher and the holder is set to twice the holding groove pitch of the carrier or the boat, but it may be set to an integer multiple of 3 or 4, if possible. As the multiple of the pitch is increased, dust adhesion / accumulation can be further reduced.

Effect of the Invention By implementing the present invention, it is possible to reduce the degree of adhesion and accumulation of dust on the pusher and the holder when the wafer is temporarily stored in the holder and when it is received and taken out from the holder. It not only contributes to the prevention of contamination and improves the processing reliability, but also improves the maintainability of the wafer sorter.

[Brief description of drawings]

FIG. 1 is a perspective view showing a holder and a pusher of a wafer sorter showing an embodiment of the present invention, FIG. 2 is a schematic side view thereof, FIG. 3 is a perspective view of a carrier for arranging wafers vertically, and FIG. Is a conceptual diagram explaining a conventional wafer changer,
FIG. 5 is a perspective view of the holder, and FIG. 6 is a perspective view of the pusher. 1 ... Wafer, 4 ... Pusher, 4a ... Holding groove, 5 ... Holder, 6 ... Tapered groove (holding groove), 9 ... Carrier, 10b, 11b.

Claims (1)

[Scope of utility model registration request] 1. An apparatus for transferring semiconductor wafers between carriers or boats on which a large number of semiconductor wafers are mounted by temporarily pushing and pushing the semiconductor wafers into a holder arranged above the carrier or boat and transferring the semiconductor wafers. The pitch dimension of the wafer holding groove of the pusher and the holder is set to be an integer fraction of the pitch of the holding groove of the carrier or boat, and when the wafer is once stored in the holder and after it is taken out from the holder by the pusher, it is removed from the carrier. A wafer changer in which a pusher and a holder can be moved by inching so that a holding groove to be used is different depending on a process of transferring to a boat and a process of transferring from a boat to a carrier.