JPH0239450A - Wafer transfer of single wafer processing device - Google Patents

Abstract

PURPOSE:To shorten time from carrying-in to carrying-out of a cassette to and from a device by providing trays for temporary storage of a wafer on the loading side and on the unloading side of a processing chamber in order to house a processed wafer in a cassette wherein the wafer was housed before being processed. CONSTITUTION:In A, an real cassette housing an unprocessed wafer is carried in from the outside of a device 6a to a cassette shed 1a, in B, wafers inside the real cassette on one hand are sent one after another to a processing chamber 5a for being sheet processed and transferred in order to a tray 3a. In the meantime, the wafers in the other real cassettes are transferred one after another on a tray 4a so as to transfer both emptied cassettes to the cassette shed 2a. Next, in C, the wafers in the tray 4a are transferred to the processing chamber 5a and during processing, the wafers in the tray 3a are housed one after another in one empty cassette of the cassette shed 2a. The wafers processed in the processing chamber 5a are housed in the remaining empty cassette. Next in D, the real cassette full of processed wafers is carried out from the cassette shed 2a outside the device 6.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a wafer transfer method in semiconductor manufacturing equipment, particularly in single-wafer processing equipment.

(Prior Art) Single wafer processing equipment is used in photolithographic exposure steps, dry etching steps, ion implantation steps, etc. during wafer processing in semiconductor manufacturing. The wafers to be processed used here are carried into and out of a predetermined location outside or inside the single wafer processing apparatus by a transport device in units of cassettes containing a plurality of wafers. Since the cassette moves up and down during transportation, negative resist adheres to the storage groove during, for example, a photolithography process. If, for example, a wafer coated with positive V Nost'l is transferred to the storage groove, the wafer will be contaminated and the yield will be reduced, so the cassettes are sorted by wafer. Furthermore, since the operating rate of a single wafer processing apparatus decreases if only a specific type of wafer is processed, several types of wafers are passed through the single wafer processing apparatus, and the conveying apparatus conveys a plurality of cassettes at the same time to improve productivity.

The entire wafer transfer method of a conventional single wafer processing apparatus will be explained below with reference to FIGS. 2A-Ei. However, in the present invention, there are two types of wafers, A and B types, and the case where two cassettes are carried in and transported at the same time by a transport device (not shown) will be described.

In addition, the cassette (in which the wafers are stored) can be used as a merit cent.
The unaccommodated cassette is defined as the f2 cassette and will be used below. Please refer to the legends in the drawings for indications on the drawings, such as the type of cassette and actual/aerodynamic cents.

1st. Second. Third cassette storage area (J b ) e (2
b).

(3b) and the single wafer processing equipment (
5b), the first cassette storage place (1b) is the device (5b).
A real cassette containing all unprocessed wafers is brought in from the outside of the processing chamber (
4b) and processed. When the actual cassette becomes empty, this empty cassette is transferred to the third cassette storage area (3b). The second cassette storage area (2b) is the third cassette storage area (3
Empty cassettes are transferred from b). When the empty cassette is filled with the processed weno material, the actual cassette is carried out to the outside of the apparatus (5b). Third
The cassette storage area (3b) has a space for placing a pair of cassettes for each type of cassette, and empty cassettes are placed at fixed locations. Then, when a certain type of wafer is washed away,
The same type of aerodynamic cent is transferred to the second cassette storage area (2b). Empty cassettes of the same type as the transferred empty cassettes are then transferred from the first cassette storage area (1b) to the empty space that has been further transferred.

First, in FIG. 2A, empty cassettes 7) (A tights) of the same type as the real cassettes (for example, type A) that are carried into the first cassette storage area (1b) prior to the subsequent process are transferred to the third cassette storage area (1b). 3b) to the second cassette storage area (2b). Next, in FIG. 2B, an actual cassette containing unprocessed wafers is carried into the first cassette storage area (1b) from outside the apparatus (5b). Next, in FIG. 2C, the wafers in either one of the actual cassettes in the first cassette storage area (1b) are sequentially sent to the processing chamber (4b) for single wafer processing, and all of the wafers are transferred to the second cassette storage area (1b). 2b) Store them in sequence in the aerodynamic cent. Next, in the second diagram, the wafers in the remaining capacity of the first cassette storage area (1b) are subjected to the same process as in the previous process. Then, when the actual cassette in the first cassette storage area (1b) becomes empty, preferably while all the last wafers are being processed, both empty cassettes in the first cassette storage area (1b) are transferred to the third cassette storage area (3b). Transfer to the A type cassette storage area. Next, in Figure 2 E, the second cassette storage area (2b)
From there, the actual cassette filled with processed wafers is carried out to the outside of the apparatus (5b).

Repeat the above steps.

In particular, here, the third cassette storage area (3b) is the device (5b).
), but it can also be outside.

(Problem to be Solved by the Invention) However, in the above method, as in the process shown in FIG. Since it is necessary to know the type of wafer in order to make the wafers the same, control of the transport device is correspondingly complicated. Furthermore, since empty cassettes are placed in the third cassette storage area for each type of wafer, there is a problem in that the third cassette storage area requires a large space when processing many types of wafers.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention provides storage containers V for temporary storage of wafers in a single wafer processing apparatus, one each on the loading side and unloading side of every processing chamber. To allow processed wafers to be stored in the same cassette as the cassette in which they were stored when unprocessed.

(Function) According to the present invention, as described above, processed wafers are stored in the same cassette as the cassette in which they were stored when unprocessed, so a third cassette storage area is not required. Therefore, the above problems can be solved.

(Example) An example of the present invention will be described using FIGS. 1A to 1D. However, in this description, a case will be described in which two cassettes are carried in and out at the same time by a conveyance device (not shown).

First, in FIG. 1A, all unprocessed wafers are loaded into the first cassette storage area (1a) from outside the apparatus (6a). Next, in FIG. 1B, the first cassette 714
The wafers in either one of the actual cassettes in the field (1a) are sent to the processing chamber (5a) for single wafer processing, and the wafers are sequentially transferred to the first tray (3a). Further, while the wafers are being processed, wafers in other actual cassettes in the first cassette storage area (1a) are sequentially transferred to the second tray (4a). Then, during the final processing of all the wafers, all empty rain cassettes in the first cassette storage area (1a) are transferred to the second cassette storage area (2a). Next, in Figure 1C,
2nd) The wafer to be processed first in L/I (4a) is sent to the processing chamber (5a), and while being processed, the wafer in L/I (4a) is
The processed wafers in ) are sequentially stored in one of the empty cassettes in the second cassette storage area (2a). The processed wafers are stored in the remaining empty cassettes in the second cassette storage area (2a). Thereafter, the wafers in the second tray (4a) are processed one after another. Next, in the first plan, the second cassette storage area (
2a) to the outside of the apparatus (6a). Repeat the above steps.

The processing time for one wafer varies depending on each process, but it is 60 seconds, and the time to transfer one wafer to the tray is 2.
Seconds, time to transport all two real or aerodynamic cents at the same time is 10
In seconds, 25 wafers are stored in one cassette. Also, 1st and 2nd ToVi (Ja), (4a)
is a cassette that temporarily stores wafers and does not transport them.
If the wafer is not being transferred, the wafer is passable.

(Effects of the Invention) As described above, according to the present invention, the number of empty cassettes to be transported can be reduced, so the time from loading the cassettes into the apparatus to unloading them can be shortened. Furthermore, the control of the transport device depending on the type of wafer is omitted, and the control of the transport device is simplified. Furthermore, since multiple types of wafers can be processed with two trays, space efficiency can be expected to improve.

[Brief explanation of the drawing]

1A to 1D are schematic diagrams showing a method for transferring wafers and cassettes in a single wafer processing apparatus according to an embodiment of the present invention, and FIGS. 2A to 2E are schematic diagrams showing a method for transferring wafers and cassettes in a conventional single wafer processing apparatus. FIG. 2a, 1b...first cassette storage area, 2a, 2b...
2nd cassette storage area, 3am 1st) L/A, 4a...
・Second tray, 5a, 4b...processing chamber, 6a, 5b・
...Single wafer processing equipment. 60 schools ■Power'! ! 1 equipment J mJq elT N <9'1 Figure 1 Procedural amendment (voluntary) l. Display of the case 1988 Patent Application No. 188133 Name of the invention Wafer transfer method for single wafer processing equipment 3, person making the amendment Address related to the case (〒105) Name (029) Representative 4 Agent address (〒108) )

Claims (1)

[Claims] A step of simultaneously transporting two actual cassettes containing unprocessed wafers from the outside of the single wafer processing apparatus into a first cassette storage area, and sequentially transporting the wafers in one of the actual cassettes in the first cassette storage area to the processing chamber. A step of processing the wafers and sequentially transferring them to a first primary storage tray, and while processing the wafers, sequentially transferring wafers in other actual cassettes in the first cassette storage area to a second primary storage tray. The process of
After the two cassettes in the first cassette storage area become empty, the two empty cassettes are simultaneously transferred to a second cassette storage area, and the first wafer to be processed in the second temporary storage tray is processed. a step of sequentially storing the wafers in the first temporary storage tray into one of the empty cassettes in the second cassette storage area while the wafers are being sent to the chamber for processing;
sequentially processing the wafers in the temporary storage tray and sequentially storing the wafers in the remaining empty cassettes in the second cassette storage area, and storing the processed wafers from the second cassette storage area outside the single wafer processing apparatus. A wafer transfer method for a single wafer processing apparatus, which comprises a process of simultaneously carrying out two wafer cassettes.