JPH10321703A - Apparatus for manufacturing semiconductor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus for manufacturing a semiconductor which does not require a highly skilled operator and can perform a re-teaching operation quickly automatically with constant accuracy. SOLUTION: Deviations for a new cassette 3 with which an old cassette 3 is replaced in the directions of x-, y-, z-axes are detected by a detecting means 10 and position data of a transfer unit 4 of the old cassette 3 stored in a memory 14 are compensated by the deviations. Then, the actual process of loading a wafer 1 into the loading groove of a cassette 3A is performed, based on the position data after the compensation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor manufacturing apparatus and, more particularly, to a semiconductor manufacturing apparatus for re-teaching the operation of a transfer machine for transferring a substrate to a substrate insertion position of a substrate storage.

[0002]

2. Description of the Related Art In a semiconductor manufacturing apparatus, a large number of wafers stored in a cassette (substrate storage unit) are loaded into a boat (substrate storage unit) by a transfer machine, and then loaded into a reaction furnace. Thus, these wafers are subjected to predetermined processing such as film formation and annealing. In addition, each wafer after processing,
From the boat discharged from the furnace, it is returned to the cassette by the transfer machine. By the way, in the transfer processing by such a transfer machine, it is necessary to accurately insert a wafer into a wafer insertion groove of a cassette or a boat. That is, the wafer is accurately positioned and inserted in the front-rear direction (X-axis direction), the left-right direction (Y-axis direction), and the up-down direction (Z-axis direction) by a tweezer, which is a wafer mounting portion of the transfer machine. There is a need. Therefore, prior to the actual transport process (actual process), the operation of the transfer machine is taught.

In the teaching of such a transfer machine, conventionally, for example, an operator manually operates the transfer machine to transfer a wafer and counts the moving distance by the number of pulses generated by a drive motor of the transfer machine. That is, it was performed by a task that was extremely dependent on the worker's sense. As a result, there is a problem that a high level of skill is required of the operator, and even if the operator is skilled, a considerable amount of time must be spent on teaching work. further,
There is a problem that it is difficult to perform a teaching operation with a constant accuracy for each semiconductor manufacturing apparatus.

Therefore, as a conventional technique for solving this problem,
For example, those described in the specification filed by the applicant of the present application earlier are known. Hereinafter, this conventional example will be described in detail with reference to FIGS. 1, 2, and 8. FIG. As shown in FIGS. 1 and 2, this semiconductor manufacturing apparatus has a boat 2 into which a large number of wafers 1 are inserted for performing predetermined processing in a reaction chamber, and a multi-stage insertion groove 3a. Then, a cassette 3 for accommodating a plurality of processed or unprocessed wafers 1, a transfer machine 4 for transporting the wafers 1 by 5 between the boat 2 and the cassette 3, and a wafer 1 by the transfer machine 4. And a controller 7 for controlling the transfer processing. The cassette 3 is mounted on a cassette shelf 6 provided in the semiconductor manufacturing apparatus. The transfer machine 4 has five tweezers 5.
Is provided.

In this semiconductor manufacturing apparatus, a detecting means 10 is provided on the front surface of the transfer machine 4 (near the tweezers 5), and the position data detected by the detecting means 10 is supplied to an analog / digital converter 11. External terminal (PC) 12 via
Is input to The detection unit 10 is a sensor that optically detects the position of the detection substrate (here, the jig 21) as described later, and this detection information is output to the external terminal 12 as position data. The controller 7 and the external terminal 12 constitute control means of the semiconductor device. Further, the semiconductor manufacturing apparatus is provided with communication control means 13 for controlling communication between the external terminal 12 and the controller 7. An operation command from the external terminal 12 is input to the controller 7 via the communication control means 13, and
The status and encoder value obtained by the controller 7 are input to the external terminal 12. The encoder value is the number of pulses generated by the drive motor of the transfer machine 4, and the operation can be controlled while detecting the movement distance of the transfer machine 4 (ie, the movement distance of the tweezers 5).

[0006] The external terminal 12 is provided with a memory 14, and the position data input from the detecting means 10 and the encoder value input from the controller 7 are stored in the memory 14. These position data and encoder values are data for controlling the operation of the transfer machine 4 as described later. In the transfer process of the wafer 1 in the actual process, the external terminal 12 and the controller 7 are stored in the memory 14. Transfer machine 4 based on data
To work.

In order to obtain the position data, in a teaching operation performed prior to the actual process, a jig 21 shown in FIG. 8 is used in place of the wafer 1 to be processed. The jig 21 includes a disk portion 21a having the same shape and the same size as the wafer 1 and a columnar pin 21b erected at the center of the disk portion 21a.

In the semiconductor manufacturing apparatus having the above-described structure, a teaching operation is performed as described below, and thereafter, a transport process of an actual process is performed. First, as shown in FIG. 2, in a teaching operation, an operator
And the right and left insertion grooves 3a of the jig 21 (see FIG. 5).
, The clearance between the jig 21 in the vertical direction with respect to the insertion groove 3a (clearance), and the clearance between the jig 21 with the insertion groove 3a at the back (clearance) so as to be a predetermined interval. adjust. The position of the jig 21 inserted into the cassette 3 with a predetermined clearance is detected by the detecting means 10 in a state where the transfer machine 4 is fixed at the home position serving as a reference position for the operation, and is obtained in this detection processing. Position data in memory 1
4 is stored.

That is, as shown in FIG. 8A, the detecting means 10 irradiates a laser beam R in the Y-axis direction (left-right direction) to detect the left and right ends of the pin 21b based on the presence or absence of reflected light. Its bisecting position (that is, the center of the jig 21)
Is detected as the position of the jig 21 in the Y-axis direction. Further, as shown in FIG. 8B, the laser beam R is vertically radiated from the detection means 10 in the Z-axis direction (vertical direction) to detect the edge of the disk portion 21a from the presence or absence of reflected light, and the position of the edge is detected. Jig 21
As a position in the Z-axis direction. Further, FIG.
As shown in (2), the detecting means 10 detects the pin 21b (that is, the center of the jig 21) based on the reflected light from the pin 21b.
(Ie, the distance between the center of the jig 21 and the transfer device 4) in the X-axis direction (front-back direction).

In the above detection processing, an optical displacement sensor is used as the detecting means 10, and this optical displacement sensor is configured by combining a light emitting element and a light position detecting element (PSD). In particular, the distance in the X-axis direction is detected by a method using triangulation. The detection processing by this sensor will be described in more detail. Light from a light emitting element, such as a light emitting diode or a semiconductor laser, is condensed by a light projecting lens and irradiated to a jig 21. A part of the light diffusely reflected from the jig 21 is condensed on the light position detecting element through the light receiving lens. The Y-axis position and the Z-axis position are detected based on the presence or absence of the collected light. At the same time, the distance in the X-axis direction is detected based on the spot position of the collected light.

That is, the light position detecting element is the sensor 10
A voltage corresponding to the distance between the tool and the jig 21 or the position of the formed spot is output, and the distance in the X-axis direction is detected based on the output voltage value. Thus, the sensor 10 as a whole has three functions of detecting the position in the Y-axis direction, the position in the Z-axis direction, and the distance in the X-axis direction. The above detection processing is performed by the transfer machine 4 and the tweezers 5.
In the home position. Also,
Even if the positional relationship between the sensor 10 and the tip of the tweezer 5 is detected and measured in advance and the operation is controlled based on the position data obtained by the sensor 10, the position of the tweezer 5 can be accurately controlled in an actual process.

In this manner, the position data at which the jig 21 (ie, the wafer 1) can be inserted into the cassette 3 in an appropriate state with a predetermined clearance is stored in the memory 1
4 is stored. Thereafter, in the actual process, the memory 14
Is output to the controller 7 and the transfer machine 4 is operated.
The cassette 3 is inserted into the insertion groove 3a of the cassette 3 with an appropriate clearance in the horizontal direction and the vertical direction. In this example, the wafer 1 is moved by the five tweezers 5 of the transfer machine 4.
Are transported five by five, and are inserted into the cassette 3 with a predetermined clearance.

By the way, the cassette 3 in which the wafers 1 are stored, for example, may be replaced to improve reliability and durability. When replacing the old cassette 3 with the new cassette 3A (see FIGS. 3 and 4), the old position data of the transfer machine 4 stored in the memory 14 is replaced with a new position suitable for the new cassette 3A after the replacement. Need to change to data. These cassettes 3 and 3A are provided by SEMI (Semiconductor Equipment).
t and Materials Institute). However, there are variations in dimensions even within this standard. In addition, when a new cassette 3A is set, the position is usually slightly shifted in each of the X, Y, and Z axis directions.

On the other hand, if the wafer 1 is not inserted into the insertion grooves 3a of the cassettes 3 and 3A with a predetermined clearance with high precision, the wafer 1 will be damaged. For this reason, after the replacement of the old and new cassettes 3 and 3A, it is necessary to perform a teaching operation with a large number of steps again. Less than,
With reference to FIGS. 9 and 10, a re-teaching operation using the conventional semiconductor manufacturing apparatus will be specifically described.

As shown in FIGS. 9 and 10, first, as in teaching, an operator places the jig 21 in a new cassette 3.
A and adjust the gap between the parts. Then, while the transfer machine 4 is fixed at the home position serving as a reference position for operation, the position of the jig 21 inserted into the new cassette 3A is detected by the detection means 10, and the position data obtained in this detection processing is obtained. It is stored in the memory 14.

More specifically, as shown in FIG. 9, the transfer device 4 at the home position is disposed below the mounting surface of the boat 2 and the transfer device 4 is irradiated with the laser beam R from the sensor 10. To rise. At this time, the jig 21 depends on the presence or absence of reflected light.
The edge position of the disk portion 21a is detected, and the height position H is detected as the position of the jig 21 in the Z-axis direction. Thereafter, this is compared with the position in the Z-axis direction at the time of the previous teaching to detect the amount of displacement of the jig 21 in the Z-axis direction. Next, as shown in FIG. 10, at the height position where the jig 21 is inserted, the sensor 10 irradiates the laser beam R in the Y-axis direction (left-right direction) by turning and irradiates the left and right ends of the pin 21b based on the presence or absence of reflected light. And the bisected position (ie, the center of the jig 21) is detected as the position of the jig 21 in the Y-axis direction. This position is compared with the position in the Y-axis direction at the time of the previous teaching, the position shift length Δl corresponding to the phase angle Δθ is measured, and this is detected as the position shift amount of the jig 21 in the Y-axis direction.

Next, the sensor 10 detects a position X (ie, the center of the jig 21 and the transfer machine) in the X-axis direction (front-back direction) of the pin 21b (ie, the center of the jig 21) based on the reflected light from the pin 21b. 4) is detected. The position X is compared with the position of the pin 21b in the X-axis direction at the time of teaching to detect the amount of displacement of the jig 21 inserted in the new cassette 3A in the X-axis direction.

[0018]

However, according to this conventional method, the jig 21 must be accurately inserted manually into the insertion groove 3a of the new cassette 3A after replacement. However, it is difficult to insert the jig 21 into an accurate position unless it is an expert, and it is difficult even for an expert to maintain a certain accuracy. there were.

The present invention has been made in view of the above-mentioned conventional circumstances, and does not require a high level of skill of an operator, and provides a semiconductor manufacturing apparatus capable of performing a re-teaching operation quickly and automatically with constant accuracy at all times. The purpose is to provide.

[0020]

In order to achieve the above object, a semiconductor manufacturing apparatus according to the present invention is directed to a semiconductor manufacturing apparatus for transferring a substrate to be processed to a substrate loading position of a substrate storage by a transfer machine. Detecting means for detecting the set position of the new substrate storage body after the replacement of the old and new substrates, and the transfer means for the substrate inserted with a predetermined clearance at the substrate insertion position of the old substrate storage body. Storage means for storing the position data of the mounting machine in advance, and storing the set position data of the new substrate storage body detected and processed by the detection means after the replacement of the new and old substrate storage bodies; and the storage means. After correcting the position data of the transfer machine with respect to the substrate insertion position of the old substrate container based on the set position data of the new substrate container, The substrate of elephant is characterized in that a control means for conveying process by the transfer unit.

According to the semiconductor manufacturing apparatus of the present invention, after the old and new substrate housings are replaced, the displacement of each of the X, Y, and Z axial directions at the set position of the new substrate housing is detected by the detecting means. Thereafter, the set position data of the new substrate storage body subjected to the detection processing is stored in the storage means. Then, the control means corrects the position data of the transfer device of the old substrate storage body stored in the storage means in advance based on the stored set position data. After that, based on the corrected position data, the transfer unit is operated by the control means to perform the actual process. As a result, the re-teaching operation can be performed quickly and automatically with constant accuracy without requiring a high level of skill of the operator.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a semiconductor manufacturing apparatus according to one embodiment of the present invention will be described with reference to the drawings. The same parts as those in the above-described conventional example are denoted by the same reference numerals, and description thereof will be omitted. As shown in FIGS. 3 and 4, the semiconductor manufacturing apparatus according to one embodiment can not only perform the automatic teaching of the operation of the transfer machine 4 at the start of operation, which is an advantage of the conventional means, but also for some reason. When the old cassette 3 in use is changed to the new cassette 3A, the transfer machine 4 is used to cope with the positional deviation at the time of setting the cassette 3A.
This device can also perform automatic re-teaching of the above operation.
The old cassette 3 and the new cassette 3A used here are SEMI standard products.

That is, as shown in FIG.
, The partial position of the new cassette 3A after replacement is detected, and the set positions of the cassette 3A in the X, Y, and Z directions are detected. After that, the detected cassette 3A
Is stored in the memory 14 through the A / D converter 11. As described above, the memory 14 stores the position data indicating the position of the jig in the old cassette 3. Therefore, this memory 14 constitutes storage means. Next, based on the set position data of the new cassette 3A stored in the memory 14, the transfer machine 4 with respect to each substrate insertion position of the old cassette 3
Correct the position data of. This is performed by the external terminal 12. Thereafter, in accordance with an operation command from the external terminal (PC) 12 based on the corrected position data, the transfer machine 4 is controlled via the controller 7 to transfer the wafer 1 to be processed in the actual process to a predetermined stage of the new cassette 3A. Is inserted with a predetermined clearance into the insertion groove 3a (see FIG. 5).

In addition to the position data of the transfer device 4 in the old cassette 3, the memory 14 stores the laser light R in the Y-axis direction (left and right) from the detecting means 10 toward the old cassette 3 before replacing the cassette. The reference angle θ between the two ends on the opening side of the cassette 3 when the irradiation is performed in the swirl direction.
0, the length a from the front end of the cassette 3A in the X-axis direction (front-back direction) to the insertion center of the wafer 1, and the lowermost insertion groove from the upper surface of the magazine plate 3b of the cassette 3A shown in FIG. The length b in the Z-axis direction (up-down direction) up to an intermediate position in the thickness direction of the wafer 1 inserted in 3a is:
Each is stored. Hereinafter, the automated re-teaching method will be described in detail with reference to FIGS.

First, a method of detecting a displacement of the new cassette 3A in the Y-axis direction will be described. That is, as shown in FIG. 6, a laser beam R is radiated from the detection means 10 in the Y-axis direction (left-right direction) to measure the angle θ1 between both ends on the opening side of the new cassette 3A. When there is a displacement in the Y-axis direction, the actually measured angle θ1 is smaller than the reference angle θ0 stored in the memory 14. The amount of displacement of the cassette 3A in the Y-axis direction can be calculated at the rate at which the angle is reduced. However, in this method, although the amount of displacement in the Y-axis direction is known, it is not possible to determine whether the displacement is left or right. Therefore, for example, another measurement reference point is provided on the opening side of the cassette 3A, and it is determined to which of the left and right sides the position is shifted by looking at the position of the reference point. When the wafer 1 is inserted, the wafer 1
May be used as a reference.

Next, a method for detecting a displacement of the new cassette 3A in the X-axis direction will be described. That is, as shown in FIG. 6, a laser beam R is radiated from the detection means 10 in the Y-axis direction, the shortest positions are detected at both ends on the opening side of the new cassette 3A, and the lengths L1 and L2 are determined. The calculation is performed based on the output voltage value of the laser light R. Next, the distance x from the detection means 10 to the end of the cassette 3A on the opening side is calculated based on the two lengths L1 and L2. Here, since the length a from the front end of the cassette 3A to the insertion center of the wafer 1 is stored in the memory 14 in advance,
By adding both, the distance from the detection means 10 to the insertion center of the wafer 1 can be determined. Then, by comparing this with the distance in the X-axis direction in the case of the old cassette 3, the amount of displacement in the X-axis direction is calculated.

Next, a method for detecting a displacement of the new cassette 3A in the Z-axis direction will be described. That is, as shown in FIG. 7, a laser beam R is radiated from the sensor 10 in the Z-axis direction and the height H of the new cassette 3A up to the upper surface of the magazine plate 3b is detected. Here, the memory 14 stores in advance the length b from the upper surface of the magazine plate 3b to the intermediate position in the thickness direction of the wafer 1 inserted in the lowermost insertion groove 3a. Therefore, if the two are added, the distance of the cassette 3A in the Z-axis direction can be determined. Thereafter, by comparing this value with the distance in the Z-axis direction of the old cassette 3 stored in the memory 14, the shift amount in the Z-axis direction is calculated. After that, the old cassette 3 stored in the memory 14 by the positional deviation of each of the X, Y, and Z axes.
The position data of the transfer device 4 is corrected, and the transfer device 4 performs the same actual process as described in the section of the prior art based on the corrected position data.

Although the above embodiment has been described by taking as an example the re-teaching of the wafer transfer processing on the cassette 3A side, the present invention is naturally applicable to the re-teaching of the wafer transfer processing to a new boat 2 after replacement. can do. Further, in the above embodiment, the transfer device 4 for simultaneously transporting five wafers 1 has been described as an example.
The number of wafers transferred by the transfer machine is not particularly limited.
Further, in the present invention, various optical sensors can be used as the detecting means 10, and for example, a sensor that detects a jig or a wafer as an image and detects the position thereof can be used. In addition to the optical sensor, for example, an ultrasonic sensor that emits an ultrasonic wave to an object and detects a distance from a time until the reflected wave returns can be used as the detection unit 10. The point is that the method is not particularly limited as long as the position of a jig or a wafer can be detected.

The technical idea of the present invention is not limited to the re-teaching of the operation of the transfer machine 4 due to the displacement of the set position of the new cassette 3A after the new and old exchanges.
For example, it can be applied to teaching an old cassette 3. That is, the sensor 10 detects the position data in the X, Y, and Z-axis directions of the respective reflectors 30 disposed on the upper and lower end plates of the old cassette 3 after the setting, and the detected position data of the respective reflectors 30 is processed. Then, the size and the set position of the cassette 3 are obtained, and the height position of the substrate insertion groove 3a of each stage disposed at a predetermined pitch is calculated.

[0030]

As described above, according to the present invention, the X, Y, and Z positional deviations of the new substrate storage body after the new and old exchanges are detected, and the positional deviations are stored in the storage means. Corrects the stored position data of the old substrate storage transfer machine and performs the actual process based on this.Therefore, it does not require a high level of skill of the operator, and it is always quick and automatic with constant accuracy. The re-teaching operation can be performed effectively.

[Brief description of the drawings]

FIG. 1 is an overall perspective view of a semiconductor manufacturing apparatus according to one embodiment of the present invention and a conventional example.

FIG. 2 is a configuration diagram of a semiconductor manufacturing apparatus according to an embodiment of the present invention and a conventional example.

FIG. 3 is a side view showing a cassette replacement operation prior to a re-teaching operation according to the present invention.

FIG. 4 is a plan view showing the cassette replacement operation.

FIG. 5 is an enlarged front view of the cassette.

FIG. 6 is a conceptual diagram illustrating a method of detecting a new cassette position in a Y direction and an X direction by a detecting unit.

FIG. 7 is a conceptual diagram illustrating a method of detecting a new cassette position in the Z direction by a detection unit.

FIG. 8 is a conceptual diagram illustrating a method of detecting a jig position by a detecting unit according to a conventional example.

FIG. 9 is a side view for explaining a method of detecting a jig arranged in a new boat in a Z-axis direction by a detecting means according to a conventional example.

FIG. 10 is a plan view for explaining a method of detecting a jig arranged in a new boat in the X and Y-axis directions by a detecting means according to a conventional example.

[Explanation of symbols]

 Reference Signs List 1 wafer, 2 boat, 3 cassette, 4 transfer machine, 5 tweezer, 7 controller (control means), 8 wafer insertion groove, 10 detection means (sensor), 12 external terminal (control means), 14 memory (storage means) ).

Claims (1)

[Claims] 1. A semiconductor manufacturing apparatus for transferring a substrate to be processed to a substrate insertion position of a substrate storage body by a transfer machine, wherein a new substrate storage body provided after the new and old exchanges is provided in the transfer machine. Detecting means for detecting the position, and the position data of the transfer machine with respect to the substrate inserted with a predetermined clearance at the substrate insertion position of the old substrate storage body are stored in advance, and after the replacement of the new and old substrate storage bodies Storage means for storing the set position data of the new substrate storage body detected by the detection means; and storing the old substrate storage body based on the set position data of the new substrate storage body stored in the storage means. Control means for correcting the position data of the transfer machine with respect to the substrate insertion position and then carrying out the transfer processing of the substrate to be processed in the actual process by the transfer machine. And a semiconductor manufacturing apparatus.