JP2000156394A - Carrier equipment and semiconductor manufacturing equipment using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To carry a wafer to a fixed position without depending on a projection amount of a wafer by comparing and operating a difference between a first address and an operated central position of a wafer, obtaining a displacement amount which is a difference between a load central position of a carrier and a central position of a wafer and correcting a fourth address according to the displacement amount. SOLUTION: A detection sensor 17 which detects an edge face of a wafer 12 is provided to a desired position, a carrier 1 is extended and moved to a first address, an extension movement amount of the carrier 1 is operated from a rotation amount of a driving source 8b when the carrier 1 is made to enter a cassette, a radius of a known wafer 12 is added to the extension movement amount, a difference between a central position of the wafer 12 loaded in a cassette and an operated central position of the wafer 12 is compared and operated, a displacement amount which is a difference between a load central position of the carrier 1 and a central position of the wafer 12 is obtained, a fourth address is corrected according to the displacement amount and the fourth address is stored in a controller 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for transferring objects and a semiconductor manufacturing device using the same, and more particularly to a device for transferring cassettes and wafers in a semiconductor manufacturing device in which a plurality of processing chambers of different types of atmosphere conditions are connected. Related to the device.

[0002]

2. Description of the Related Art As a semiconductor device manufacturing apparatus which requires a pattern rule of the order of submicrons, a cassette containing a plurality of wafers is used.
A transfer device placed on the atmosphere side generally called an arm type as described in No. 85, an introduction chamber, and an opening / closing gate valve capable of hermetically sealing around the transfer chamber adjacent to the introduction chamber. Preparing multiple processing chambers of different types for cleaning, film formation, etching, annealing, etc., and performing various processes consistently in an atmosphere isolated from the atmosphere to prevent contamination of semiconductor wafers and improve throughput A multi-process apparatus aiming at improvement has been proposed.

FIG. 5 is a plan view showing a transfer device and a cassette portion of a conventional semiconductor manufacturing apparatus. The supply of the semiconductor wafers to such a semiconductor manufacturing apparatus is performed via an automatic transfer device or manually by a cassette 18 accommodating a plurality of semiconductor wafers 12. In this case, the semiconductor wafer 12 in the cassette 18 often jumps out of the cassette 18 for some reason such as vibration during automatic conveyance or vibration during supply of the cassette 18 to the semiconductor manufacturing apparatus.

Conventionally, as shown in FIG. 5, a sensor 26 for detecting pop-out is disposed near the entrance of the semiconductor wafer 12 in the cassette 18. The semiconductor wafer 12 projecting from the cassette 18 is loaded as it is, for example, on the carrier 1 of a transfer device 21 generally called an arm type, and a stage (not shown) in a predetermined introduction chamber (not shown). ).

[0005] Generally, the teaching of the transfer device 21 in the straight and rotational directions excluding the teaching in the direction of gravity and the transfer of the semiconductor wafer 12 between the cassette 18 and the introduction chamber as an example are performed in the following steps.

The carrier 1 is inserted into the cassette 18, and a position where the center of storing the semiconductor wafers 12 in the cassette 18 and the loading center of the carrier 1 approximately match is set as a first address as viewed from the origin of the transfer device 21 by the controller (FIG. (Not shown). Next, the carrier 1 is moved straight so as to retreat from the cassette 18, and the position where the carrier 1 can be turned is stored in the controller as the second address. Then career
1 is stored in the controller as a third address with the position facing the stage to which the semiconductor wafer 12 is transferred. Next, the carrier 1 is made to enter the stage, and a position where the center of the semiconductor wafer 12 and the center of the stage substantially match is stored in the controller as a fourth address.

The carrier 1 extends to the center position of the cassette 18 which is the first address where the teaching has been performed, and then the carrier 1 moves in the direction of gravity to move the semiconductor wafer 12 in the cassette 18 onto the carrier 1. Put on. Next, the carrier 1 performs the degenerate movement to the second address, and then performs the rotational movement to the third address facing the introduction chamber. After that, the carrier 1 is extended and moved to a position near the center of the stage in the introduction chamber, which is the fourth address, and then the carrier 1 is moved in the direction of gravity, so that the semiconductor wafer 12 on the carrier 1 is moved.
Is transferred to the stage. After the transfer, the carrier 1 is degenerated and moved to the third address. Through the above steps, the semiconductor wafer 12 in the cassette 18 is transferred to the introduction chamber of the semiconductor manufacturing apparatus. In the reverse process, the semiconductor wafer 12 in the introduction chamber is transferred to the cassette 18.

The semiconductor wafer 12 transferred to the stage in the introduction chamber is transferred to a processing chamber by a vacuum transfer device.
The carrier 1 of the vacuum transfer device is loaded with the outer diameter of the semiconductor wafer 12 as a reference.
It was larger than 12 calibers.

[0009]

SUMMARY OF THE INVENTION Protrusion detection sensor 26
Detects that the semiconductor wafer 12 has jumped out, the control unit 27 of the semiconductor manufacturing apparatus determines that the transfer is impossible, and requests the operator to resupply the cassette 18. In this case, naturally, the operation of the apparatus is stopped, which causes a problem of lowering the operation rate and the reliability.

The setting of how far the detection area of the pop-out detection sensor 26 detects when it pops out is related to the loading diameter of the carrier 1 on the vacuum transfer device side.
was difficult. If the transfer is performed in an insufficiently adjusted state, the semiconductor wafer 12 transferred into the introduction chamber is not normally transferred to the carrier 1 of the vacuum transfer device, and the position of the semiconductor wafer 12 shifts during the vacuum transfer process, There is a problem that it may cause a transportation accident such as dropping.

Further, it is necessary to increase the loading diameter of the carrier 1 of the vacuum transfer apparatus in advance, assuming the amount of protrusion of the semiconductor wafer 12, so that the positional deviation of the semiconductor wafer 12 at the transfer destination cannot be tolerated with a considerable margin. There is a need to not. For this reason, in a single semiconductor manufacturing apparatus having a configuration in which a plurality of cassettes 18 are stacked as well as between apparatuses, there is a large number of transport accidents in the transport between apparatuses due to variations in the amount of protrusion of wafers. In addition, there is a problem that it is difficult to construct automatic transfer between apparatuses.

[0012]

In order to solve the above problems, in the present invention, a semiconductor wafer transfer process is performed as follows.

A detecting means for detecting the end surface of the semiconductor wafer when the carrier extends is provided at a known desired position from the loading center position of the carrier. The carrier is extended and moved to the first address. When the carrier enters the cassette, a detector provided on the carrier detects an end face of the semiconductor wafer to be unloaded. The amount of extension movement of the carrier at the time of detection is calculated from the amount of rotation of the drive source using Equation 1 described later.

The center position of the semiconductor wafer stored in the cassette is calculated by adding the radius of the known semiconductor wafer to the amount of extension movement obtained by the above calculation. Then, the difference between the first address and the calculated center position of the wafer is compared and calculated, and a displacement amount, which is the difference between the center position of loading the carrier and the center position of the wafer to be unloaded, is obtained. Next, a new fourth address obtained by correcting the fourth address according to the displacement amount is stored in the controller.

The carrier is extended and moved to the first address,
After loading the semiconductor wafer in the cassette on the carrier,
The carrier is retracted to the second address, and the carrier is rotationally moved to a third address facing the stage to which the carrier is to be transferred. The calculation operation and the moving step of the carrier to the third address are performed in parallel. Next, the carrier is extended and moved to a new fourth address, so that the semiconductor wafer is transferred to a position where the center of the semiconductor wafer substantially coincides with the loading center of the stage.

Conversely, the step of transferring the semiconductor wafer from the stage to the cassette can be obtained by taking the above-described steps in reverse. In other words, the fourth
And the end face of the semiconductor wafer on the stage is detected by a detector provided on the carrier. The amount of extension movement of the carrier at this time is calculated from the amount of rotation of the driving source using Equation 1, and the radius of the known semiconductor wafer is added to the amount of extension movement to calculate the center position of the wafer on the stage. Next, a difference between the fourth address and the calculated center position of the wafer is compared and calculated, and a displacement amount, which is a difference between the center position of loading the carrier and the center position of the wafer on the stage, is obtained. Next, a new first address obtained by correcting the first address according to the displacement amount is stored in the controller. The carrier is extended to the fourth address, and the semiconductor wafer on the stage is loaded on the carrier.

Next, the carrier is retracted to the third address, and the carrier is rotated to the second address facing the cassette. The above calculation is performed in parallel with the step of moving the carrier to the second address. By extending the carrier to the new first address, the semiconductor wafer is transferred to a position where the center of the semiconductor wafer on the carrier substantially matches the center of the cassette.

By this operation, the time required for transportation is
It can be executed in the same time as the step of transporting without correction, and can be reliably transferred to the loading center position of the transport destination.

[0019]

FIG. 1 is a side view of an arm-type transfer device according to a first embodiment of the present invention. FIG. 2 is a perspective view of a carrier showing a first embodiment of the present invention, and FIG. 3 is a perspective view of a carrier showing a second embodiment of the present invention. In the present specification, members using the same reference numerals indicate members having equivalent functions.

The transfer apparatus 21 according to the present embodiment includes a carrier 1 on which the semiconductor wafer 12 is loaded, an arm 2 having a plurality of arms for extending, retracting, and rotating the carrier 1, and a drive for driving the arm 2. Unit 3, drivers 4a and 4b for driving the driving unit 3, a controller 5 for controlling the drivers 4a and 4b,
The arithmetic unit 6 corrects the amount of extension movement of the carrier 1, and the sensor unit 7 detects the end surface of the wafer.

The first arm 8 is connected to a driving source 8b,
The second arm 10 is connected to the first arm 8 via a rotatable bearing 11, and the carrier 1 on which the semiconductor wafer 12 is loaded is connected to the second arm 10 via the rotatable bearing 11. ing. Pulleys 15 are coupled to the rotation shaft 13 of the second arm 10 and the output shaft 14 of the drive source 8a, and to the rotation shaft 13 of the carrier 1 and the rotation shaft 13 of the second arm 10, respectively. They are connected by a belt 16. The stretching and contracting movement of the carrier 1 is obtained by rotating the driving source 8b, and the rotating movement of the carrier 1 is obtained by rotating the driving source 8a. The semiconductor wafer 12 is located at a predetermined position from the loading center position of the carrier 1, that is, a predetermined position from the rotation shaft 13 of the carrier 1.
A pair of transmission-type detection sensors 17 for detecting the end surfaces of the light-receiving elements are provided.

In this embodiment, a transmission type optical sensor is used to improve the reliability of detection.
Similar effects can be obtained by using the reflection type detection sensor 17 or the capacitance type detection sensor as in the embodiment.

FIG. 4 shows an embodiment of a semiconductor manufacturing apparatus using the transfer apparatus according to the present invention. This apparatus includes a transfer device 21 for loading and unloading a cassette 18 and a semiconductor wafer 12 stored in the cassette 18 to and from a stage 20 in a load lock chamber, and a processing chamber 22 adjacent to the load lock chamber for performing various processes. A vacuum transfer device 23 for transferring a wafer to the processing chamber 22, a transfer chamber for housing the vacuum transfer device 23,
It consists of 24 and so on.

The transportation according to the present invention is performed as follows. Teaching is performed in the same manner as in the related art. Career
The drive source 8b is rotated from the controller 5 via the driver 4b so that 1 moves to the first address where the storage center of the cassette 18 and the loading center of the carrier 1 approximately match.
While the carrier 1 extends and enters the cassette 18, the detection sensor 17 provided on the carrier 1 detects the end face of the semiconductor wafer 12 and sends a detection signal to the sensor unit 7. The sensor unit 7 monitors the signal of the detection sensor 17 and the rotation amount of the drive source 8b, and calculates the extension movement amount of the carrier 1 from the rotation amount ΘS of the drive source 8b at the time of receiving the detection signal using Equation 2. I do.

Equation 1 indicates the driving source 8 in the arm-type transfer device 21.
6 shows the relationship between the rotation angle amount の b and the stretching movement amount L of the carrier 1. In Equation 1, r1 is the length between the joints of the first arm 8, r2 is the length between the joints of the second arm 10, and LS is the length from the rotation axis 13 of the carrier 1 to the detection position of the detection sensor 17. It is. In general, the length r1 of the first arm 8 and the length r2 of the second arm 10 in the arm-type transfer device 21 are equal, and in this case, Expression 1 is represented by simplified Expression 2.

[0026]

(Equation 1)

[0027]

(Equation 2)

An arm-type transfer device 21 described in the present embodiment will be described below.
Obeys this condition. The value obtained by adding the radius R of the semiconductor wafer 12 to the extension movement amount L calculated from Equation 2 is the extension movement amount LC required up to the center of the semiconductor wafer 12 to be unloaded, and the extension movement amount LC and a command from the controller 5. The extension movement amount X1 of the carrier 1 up to the first address is calculated, and the displacement amount, which is the difference between the center position of the semiconductor wafer 12 to be unloaded and the first address, is calculated by Expressions 3 and 4.
Calculate Xδ.

[0029]

(Equation 3)

[0030]

(Equation 4)

Next, the fourth address, which is the destination of the loaded semiconductor wafer 12, is corrected by the previously calculated displacement amount, and stored in the controller 5 as a new fourth address. The rotation angle amount ΔT of the drive source 8b required for the extension movement amount of the carrier 1 to the new fourth address after the correction is obtained by Expression 5. Where X
Reference numeral 4 denotes the extension movement amount of the carrier 1 to the old fourth address.

[0032]

(Equation 5)

The amount of extension movement of the carrier 1 when entering the cassette 18 follows the first address previously instructed by the controller 5. Therefore, the center of the semiconductor wafer 12 loaded on the carrier 1 and the loading center of the carrier 1 are necessarily shifted. Since the carrier 1 has a vacuum suction function 28 as shown in FIG. 2 or FIG. 3, the semiconductor wafer 12 can be held even when the loading position of the semiconductor wafer 12 is shifted.

Next, the carrier 1 is degenerated to the second address. Next, the carrier 1 is rotationally moved to a third address where the carrier 1 faces the introduction chamber 19. The above-described series of calculations can be performed during the process of moving the carrier 1 to the second and third addresses after the detection sensor 17 detects a wafer. Next, the drive source required to extend and move carrier 1 to the new corrected fourth address
The controller 5 instructs the driver 4b to drive the rotation angle amount ΔT of 8b to the driver 4b, and causes the carrier 1 to enter the stage 20 in the introduction chamber 19. At this time, the stop position of the carrier 1 is set at the loading center of the
Is not the position where the center position of stage 20 approximately matches,
It stops at a position where the center position of the semiconductor wafer 12 loaded on the carrier 1 and the center position of the stage 20 in the introduction chamber 19 approximately match.

With the above transport sequence, the cassette
Even if the amount of protrusion of the semiconductor wafer 12 stored in 18 varies, the position of the semiconductor wafer 12 loaded on the carrier 1 is grasped, and not the address where the movement amount of the carrier 1 of the transfer destination is taught, By controlling according to the newly calculated new address, the semiconductor wafer 12 can always be transferred to a position where the center of the semiconductor wafer 12 and the loading center of the transfer destination are approximated as much as possible.

Similarly, when carrying out from the introduction chamber 19 to the cassette 18, the operation can be performed in the reverse manner. In this case, it is necessary to replace X4 and X1 in Equations 3 and 5, respectively.

By adopting the transfer sequence according to the present invention, even if the semiconductor wafers 12 in the cassette 18 jump out at random, the transfer can be carried out to the vicinity of the center of the transfer destination without impairing the transfer throughput. Since the emergency stop of the equipment due to a transport accident is greatly reduced, continuous operation is possible and the operation rate is improved, and the equipment can be stored in the cassette 18 after processing, so the reliability of the equipment is improved. It can be greatly improved. In addition, since a wafer ejection sensor is not required, it is possible to contribute to the cost reduction of the equipment. In addition, it is possible to construct an automatic transfer system that can be performed between multiple semiconductor manufacturing equipment as well as a single semiconductor manufacturing equipment that is reliable and reliable. It will be easier. Further detection sensor 17
By also using the function as a wafer sensor for detecting the presence or absence of the semiconductor wafer 12, it is possible to detect that there is no semiconductor wafer 12 that should be at the transfer position for some reason, so that the reliability of the apparatus can be further improved.

In this embodiment, an arm-type transfer device is described. However, the present invention is not limited to the form of the transfer device, and can be similarly applied to a frog-type transfer device.

The application of the transfer device according to the present invention is shown in FIG.
However, the present invention is not limited to the embodiment, and can be applied to a semiconductor manufacturing apparatus using a transfer device for unloading and loading semiconductor wafers stored in a cassette one by one, for example, an electron beam drawing apparatus or a semiconductor polishing apparatus. Of course. Further, the transfer object is not limited to a semiconductor wafer, and can be used as a transfer device for a liquid crystal panel production line using a thin film transistor or a production line for a plasma display panel, for example. The same effect as the effect can be obtained.

[0040]

According to the present invention, the semiconductor wafer 12 can be transferred to a fixed position without impairing the transfer throughput without depending on the amount of the semiconductor wafer 12 protruding from the cassette 18. Therefore, the pop-out detection sensor 26 becomes unnecessary, and the emergency stop of the device due to a transport accident is reduced, so that the operation rate and reliability of the device are improved. Further, after the processing, the wafers can be housed together in the cassette 18, thereby facilitating the construction of the transfer system in a single semiconductor manufacturing apparatus and the construction of the automatic transfer system performed between a plurality of semiconductor manufacturing apparatuses. .

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a transport device according to a first embodiment of the present invention.

FIG. 2 is a perspective view of the carrier according to the first embodiment of the present invention.

FIG. 3 is a perspective view of a carrier according to a second embodiment of the present invention.

FIG. 4 is a plan view of the semiconductor manufacturing apparatus of the present invention.

FIG. 5 is a plan view illustrating a cassette and a transfer device of a conventional semiconductor manufacturing apparatus.

[Explanation of symbols]

1 ... Carrier, 2 ... Arm, 3 ... Driver, 4a ... Driver, 4b ... Driver, 5 ... Controller, 6 ... Calculator, 7 ...
Sensor unit, 8: first arm, 8a: drive source, 8b: drive source, 10
... second arm, 11 ... bearing, 12 ... semiconductor wafer, 13 ... rotary shaft, 14 ... output shaft, 15 ... pulley, 16 ... belt, 17 ... detection sensor, 18 ... cassette, 19 introduction chamber, 20 ... stage, twenty one…
Transfer device, 22 processing chamber, 23 vacuum transfer device, 24 transfer chamber, 25 pin, 26 protrusion detection sensor, 27 control unit,
28… Vacuum suction function.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Masafumi Kinyu 1-280 Higashi Koigakubo, Kokubunji-shi, Tokyo F-term in Central Research Laboratory, Hitachi, Ltd. 5F031 CA02 DA01 DA17 FA01 FA03 FA11 FA12 GA08 GA43 GA47 GA48 JA05 MA06

Claims (7)

[Claims] 1. An arm unit comprising at least one or more carriers for loading an object to be conveyed, a plurality of arms for extending, retracting, and rotating the carrier in a direction perpendicular to the direction of gravity, and power to the arm unit. In the transfer device configured by a drive unit that transmits the carrier, the predetermined extension movement amount of the carrier, according to the displacement amount of the center position of the transported object loaded on the carrier and the predetermined loading center position of the carrier A transport device for correcting. 2. A carrier device according to claim 1, further comprising a sensor for detecting an end face of said conveyed object in a process of extending said carrier by a predetermined moving amount, and extending said carrier from a detection position of said sensor. A calculating circuit for calculating a displacement amount between the center position of the transported object after the moving step and a predetermined loading center position of the carrier, and a correction means for correcting a predetermined extending movement amount of the carrier according to the displacement amount. A transfer device, comprising: 3. The transfer device according to claim 1, wherein the carrier is extended and moved by a first predetermined amount to receive the object to be transferred to the carrier, and the carrier is moved to a second predetermined position. A second step of reducing the amount of movement, a third step of rotating the carrier by a third predetermined amount of movement, and extending the carrier by a fourth predetermined amount of movement to move the object. A fourth step of transferring from the carrier to the destination, wherein the fourth step includes detecting the end face of the transported object by the sensor in the first step, and performing the second step and the second step. By performing the calculation of the displacement amount and correcting the fourth predetermined movement amount during the process of 3, and extending the carrier by the corrected fourth predetermined movement amount,
A transfer device for transferring the object to a transfer destination. 4. A semiconductor manufacturing apparatus comprising the transfer device according to claim 1, wherein the object to be transferred is a semiconductor substrate. 5. The semiconductor manufacturing apparatus according to claim 4, wherein
A semiconductor manufacturing apparatus, comprising: a cassette capable of storing a plurality of at least one semiconductor substrate disposed at a predetermined position; and a processing table for processing at least one semiconductor substrate in the cassette. . 6. The transport device according to claim 1, further comprising a detection function for detecting the presence or absence of the transported object on the carrier. 7. The semiconductor manufacturing apparatus according to claim 4, wherein the means for performing the processing includes means for forming a desired pattern on a semiconductor substrate using a desired gas, A means for processing a semiconductor substrate; a means for self-growing a desired pattern; a means for removing or processing a desired pattern; a means for depositing a desired pattern; and a means for flattening a semiconductor substrate A semiconductor manufacturing apparatus characterized by comprising means.