JPS61248839A - Takeout device for housed wafer - Google Patents

Abstract

PURPOSE:To prevent any damage to a wafer and a takeout arm from occurring at the time of takeout operation, by applying light to each wafer mounted on plural stages inside a carrier, while detecting the attitude. CONSTITUTION:Each of wafers 3a-3l is horizontally placed on plural stages 2a-2a'-2l-2l' of a carrier being mounted on a pallet 1 moving in an arrow A direction, and a front opening 2M and a rear opening 2N opposed to the former are set down to a takeout port of these wafers and each passage of light out of projectors 6a and 6b parallelly set up in horizontality. When these wafers 3a and so on are righteously mounted on these stages 2a-2a', each output of light receivers 7a and 7b is largely reduced together but, for example, when the wafer 3c is placed aslant between both third and fourth stages 2c and 2d, the output of the light receiver 7a is small while the output of the light receiver 7b is large whereby it judges that an attitude of the wafer 3c is not righteous, emitting a warning and stopping other motions, and an operator remounts it for a righteous attitude.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention relates to a wafer take-out device that takes out substrates one by one from a carrier that stores a plurality of substrates.

(Background of the Invention) Conventionally, it has been known to take out wafers (substrates) one by one from a carrier and supply them to a wafer inspection apparatus. However, if the wafer is not placed in the correct position on the carrier, there is a risk that the wafer itself or the arm used to take out the wafer may be damaged.

The present invention aims to eliminate these drawbacks and to prevent the wafer or the means for removing the wafer from being destroyed.

(Example) Figures 3 and 3 are block diagrams, and Figures 4 and 5 are flowcharts.

In FIG. 1, a pallet 1 is moved in a direction A by a transport mechanism (not shown). The wafer carrier 2 is placed on the pallet 1. As shown in FIG. 2, the carrier 2 has a plurality of stepped portions 2a-2a', 2b-2b', 2C-2C',
2d-2d' --- has one. wafer 3a,
3b, 3cm---3, 31 are the stepped portions 2a-2, respectively.
a', 2b-2b', 2cm2C' ---2 to -2', 2It-2ffi'. Each step is configured to horizontally place a wafer. On the front side of the carrier 2, wafers 3a, 3b---3, 3
An opening 2M is formed through which the item 1 can be taken out, and an opening 2N is also formed on the rear surface opposite to this. However, this opening 2N is for wafers 3a, 3b---
31 is large enough to prevent removal. The elevator 4 lifts the pallet 1 sent by the transport mechanism upwards (direction B).
It is driven by a motor 5 (see Figure 3). The projectors 5a and 5b are arranged horizontally side by side. The receivers 7a and 7b are also horizontally arranged side by side.

The projectors 6a and 6b face each other. The guide 8 and the male screw 9 are supported by a support plate 10.11 so as to be parallel to each other. The male screw 9 is connected to the support plate 1 by the motor 12.
Rotated on 0.11. The arm support stand 13 is the guide 8
and screw it onto the screw 9. Arm 14 is support base 13
It is rotatable in the C direction around the rotating shaft 13a. The arm 14 is driven by a motor 15 (see Figure 3). The contact sensor 16 is provided at the tip of the arm 14.

As shown in FIG. 3, the aforementioned motors 5, 12, and 15 are all controlled by a microcomputer 17 (hereinafter referred to as CPU) consisting of 5 arithmetic processing units, a part of memory, an I10 unit, etc. In addition, a contact sensor 16 and a warning means 1 to be described later.
8 is also connected to the CPU 17.

The operation of the embodiment apparatus will be described below with reference to the flowcharts of FIGS. 4 and 5.

First, the pallet 1 is driven in the A direction by the conveyance mechanism, and the pallet 1 is brought to a predetermined position.

The CPU 7 outputs a command to set the initial detection position. Then, the motor 5 is driven and the elevator 4 raises the pallet 1, and the wafer 3a placed on the uppermost stage 2a-2a'' of the carrier 2 is exposed to the openings 2N, 2 through the light emitting lights 6a+6b.
When the elevator 4 is positioned in the optical path leading to the light receivers 7a and 7b via M, the elevator 4 stops operating.
The output of 7b is taken in and the attitude of the wafer is determined.

In Fig. 2, 218.21b marked with a mark indicates the optical path from the emitter (ia, 5b) to the receivers 7a, 7b, that is, as shown in Fig. 2, the wafer 3a is placed on the step 2a-2a° If it is placed in the posture, the receiver 7a
, 7b both decrease significantly, and CP
The CPU 17 determines whether the wafer is placed in the correct orientation (X). When determining that the wafer is placed in the correct orientation, the CPU 17 (1) stores the determination output in the memory. Next, the CPU 7 determines whether all wafers have been checked. In this case, since the first wafer has just been checked, the 2nd determination output is an output indicating that not all wafers have been checked. Therefore, the CPU 17 operates the motor 5 to raise the elevator 4 by one step of the carrier set in advance, more specifically, by the distance from one step to another step adjacent to this step. And the second row 2b-
The wafer 3b placed on the wafer 2b' is positioned within the optical path from the light emitters 6a, 5b to the light receivers 7a, 7b. The marks 22a, 22b in FIG. 2 indicate the optical path at this time.

In this case, since the wafer 3b is placed in the correct posture on the stepped portions 2b-2b', the above-described steps 1 to 2 are performed again, and the elevator 4 is further raised by one stage of the carrier. The CPU 17 then proceeds to step (2). *mark 23a, 2 in Figure 2
3b is from the emitters 6a, 6b to the receivers 7a, 7b at this time.
Shows the optical path leading to. In this case, originally the third stage 2C-2C'
The wafer 3C that should have been placed on the third step 2C
diagonally between and the fourth step 2b'! ! It is placed. Therefore, is CPtJ17 a light receiver? a.

The output of 7a is smaller than the output of 7b.

From the large output of 7b, it is determined that the wafer 3C is not placed in the correct posture (y).

Then, the CPU 17 activates the warning means 18 to give a warning using the sounding body and visual display means, and stops other operations. In this case, the operator places the wafer 3C on the step 2.
All you have to do is reposition it so that it has the correct posture at cm2c'.

Next, the operation after remounting the wafer 3C will be described. When you press the start button (not shown).

The CPU 17 returns to the process of ■ again, and performs ■ to ■ in the same way as above.
Repeat the process to check whether the wafer 3a is placed in the correct posture on the second stage portion 2a-2a''.

It is determined whether or not the wafer 3b is placed in the correct posture on the stepped portion 2b-2b'. Then, return to step (■) again. Wafer 3C is already on step 2C-2C°.
Similar to a and 3b, it has been remounted in the correct posture.

Therefore, in this case as well, steps ① to ① are performed as in the case of wafers 3a and 3b. Then, the elevator 4 further rises by one stage of the carrier, and positions the wafer that should originally be placed on the nine stage portions 2d-2d' within the optical path from the light emitters 6a, 6b to the light receivers 7a, 7b. However, no wafer exists on this step portion 2ct-2a'.

Therefore, when the CPU 17 moves to the determination operation (2), since the outputs of the light receivers 7a and 7b are both large, the CPU 17 determines that there is no wafer on the stepped portions 2d-2d' (2), and the CPU 17 determines (2) Store the output in memory.

Next, the CPU 7 goes through the steps ① and ②, returns to the step ② again, and repeats the steps ② to ② to determine whether the wafer is placed in the correct posture on each stage. Then, the lowest wafer 31 is positioned in the optical path connecting the emitters 6a, 6b and the receivers 7a, 7b. The operation moves on to the flowchart shown in FIG.

As is clear from the above description, in the flowchart of FIG. 4, if it is determined in step (2) that the wafer orientation is correct (X), the process returns to (X) through steps (1) to (2). Further, if it is determined that the posture is incorrect (y), the process returns to ■ and a warning is issued. Furthermore, if it is determined that no wafer exists (2), the process returns to ■■■ and then returns to ■.

Next, the operation of the CPU 17 according to the flowchart in FIG. 5 will be explained. First, the CPU 17 (1) completes wafer inspection (later step) for all wafers stored in the carrier 2, and then determines whether all wafers have been stored in the carrier 2 or not. At this point, the wafer inspection is completed for all wafers, and if all the wafers are stored in the carrier 2, the flow shown in FIG. 5 ends. If all wafers have not been inspected and stored, the process moves to the next step @.

The CPU 7 determines whether or not the wafer to be taken out is present on the stepped portion based on the information stored in the memory of the CPU 17 (discrimination outputs of ■ and ■). If there is no wafer, the CPU 17 drives the [phase] motor 5 to lower the elevator 4 by one stage of the carrier. If the wafer to be taken out is present in the stepped portion, the process moves to step 0. Implement this. And the bottom row 27! A wafer exists at -2ffi'. Therefore, after the [phase] process,
When the CPU 17 issues a command to set the arm 14, the motor 12 is driven, and as the male screw 9 rotates, the support stand 13 is guided by the guide 8 and moves in the D direction. The arm 14 extends from the opening 3M to the lower nine steps 2 of the wafer 31.
It enters between 1 and 2ffi' and stops. At this time, there is still arm 14 and wafer 3j! is the non-contact zero-order CP
U17 issues a command to slightly move the elevator 4 downward, so the motor 5 is driven and the elevator 4 is activated)
The primary CPU 17, which moves the wafer 3E and the carrier 2 slightly downward (direction F), takes in a signal from the [phase] contact sensor 16 and determines whether or not the wafer 3E has contacted the sensor 16.

If there is no contact, return to [phase] and repeat the lowering of the elevator 4 until contact occurs. If it is determined that there has been contact, the CPU 17 issues a command to slightly move the elevator 4 further downward, and the motor 5 causes the wafer 31 to slightly float away from the stepped portion 2Il-211'. , and wafer 3
j! is such that it does not touch the step 2 above it. In this way, the wafer 31 is placed in the tube of the arm 14. Next, the CPU 17 issues a command to take out the 0 wafer, so the motor 12 is driven and the support base 13 is moved to the E
direction, and the wafer 3E is taken out. Then, the motor 15 is further driven, the arm 14 rotates in the C direction, and the wafer 3.1 is supplied to a wafer inspection device (not shown). A wafer inspection device (not shown) inspects the supplied wafer. [Phase] The CPU 17 determines whether or not the wafer inspection has been completed for the wafer supplied to the wafer inspection device.

If the wafer inspection has not been completed, this determination is repeated at predetermined time intervals, which is the standby state. When determining that the wafer inspection has been completed, the CPU 17 stores the [phase] wafer in its original position within the carrier 2. This behavior is @
Since the operation is completely opposite to that shown in .about.0, it will not be described in detail. The wafer 31, which has thus completed the wafer inspection, is returned to its original position (2j!-27!').Then, the CPU 17 drives the motor 5 at the end of the [phase], and moves the elevator 4 to carry A stages. After that, the CPU 17 returns to step O. By repeating the above-mentioned operation, the wafer 3j---1 wafer inspection is performed on the wafer 3. In this embodiment, the stepped portions 2d-2d' of the carrier are inspected. Since there is no wafer above, if it is determined in the step @ that there is no wafer, the elevator 4 is lowered by one step of the carrier 2 in step 0, and then returns to the step @ after passing through ■. It is determined that the wafer 3c is on the part 2cm2C', and the process from @ is repeated.Finally, the wafer inspection of the wafer 3a is completed, and the [phase]
When the step (2) is completed, the CPU 17 moves to the step (2), and determines that wafer inspection has been completed for all wafers stored in the carrier 2. In this way, the operation according to the flowchart of FIG. 5 is completed. After this, the elevator 4 is lowered, and the pallet 1 is transported in the A direction by the transport mechanism.

As described above (according to this embodiment, the posture of each wafer in the carrier is detected by the light emitter and the light receiver).

Since a warning is issued if the wafer is not in the correct position, each wafer can be adjusted to its correct position when taken out by the arm. Therefore, when a wafer is taken out by the arm, the tip of the arm comes into contact with the end surface of the wafer stored diagonally.

There is no possibility of damaging the wafer itself or the arm.

In this embodiment, two light emitters 6a and 6b and light receivers 7a and 7b are used.
and the CPU 17 constitute posture inspection means.

In the above-mentioned embodiment, when the judgment of y is made in the step of ■, the process moves to the step of ■ and the warning means 18 is activated, but when the judgment of y is made in the step of However, after that, the process may proceed to step (2). In this case, when confirming the presence of a wafer in the @ step, the same process as when the wafer does not exist may be performed.

In other words, the process may be shifted to [phase] after the process of [phase]. In this way, the arm will not take out a wafer with an incorrect orientation. Therefore, there is no risk that the wafer itself or the arm will be destroyed.

In the above-described embodiments, a case has been described in which the carrier stores a wafer, but the carrier may also store a reticle. In this specification, the term "substrate" includes the wafer and the reticle.

Further, in the above-described embodiment, the wafer taken out from the carrier is supplied to the wafer inspection apparatus, but it does not necessarily have to be supplied to the wafer inspection apparatus, that is, it may be supplied to another separate apparatus.

(Effects of the Invention) As described in detail above, according to the present invention, when the substrate is taken out from the carrier, the substrate itself or the means for taking out the substrate is not destroyed.

[Brief explanation of drawings]

1 to 5 show an embodiment of the present invention, FIG. 1 is a perspective view of the embodiment device, FIG. 2 is a sectional view of the carrier, FIG. 3 is a block diagram, and FIG. 4 is a diagram of each wafer. FIG. 5 is a flowchart when detecting the state of wafers, and FIG. 5 is a flowchart when taking out each wafer. [Explanation of symbols of main parts] 2 ----Carrier 2a
-2a', 2b-2b'----211-21'-
111 step section

Claims (1)

[Claims] A device for taking out stored wafers, comprising a posture inspection means for detecting the posture of each substrate by irradiating light onto each substrate placed in a plurality of stages within a carrier.