JP2002141394A - Inspection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inspection device capable of detecting whether or not a plurality of substrates housed in multiple stages inside a container are aligned and arranged. SOLUTION: This inspection device for detecting whether or not the plurality of the substrates 102 housed in the multiple stages inside the container 100 are aligned and arranged is provided with two sensors for outputting signal strings changed by the presence/absence of the substrates 102, and a moving unit for moving the two sensors in the direction of crossing the substrates 102. By comparing the data of the signal strings from the two sensors with the data of a prescribed comparison signal string, whether or not the substrates 102 are aligned and arranged is judged.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inspection apparatus,
In particular, wafers in the manufacture of semiconductors and liquid crystal display devices,
The present invention relates to an apparatus for inspecting the arrangement of a substrate such as a glass substrate.

[0002]

2. Description of the Related Art In the manufacture of semiconductors and liquid crystal display devices, when a substrate such as a wafer or a glass substrate to be processed is transferred to each processing facility, a container called a cassette or a pod is used. Have been.

FIG. 8 is an external view showing an example of such a container. In the container 100, a plurality of substrates 102 are locked in grooves 101 provided on the inner wall of the container 100, and a plurality of substrates 102 are provided. Are located in In each processing facility, the substrate is taken out of the container and subjected to necessary processing, and after the processing, the substrate is returned to the container again.

[0004]

Here, in order for each processing facility to properly acquire the substrate in the storage container, the substrate in the storage device needs to be always aligned. For example,
As shown in FIG. 9, the board in the container 100 is missing (111), a plurality of sheets are overlapped (112),
Alternatively, if it is arranged in an inclined manner (113), there will be a problem in each processing facility that the acquisition of the substrate 102 in the storage container 100 will be hindered, and the processing will be interrupted or the substrate will be damaged.

Accordingly, an object of the present invention is to provide an inspection apparatus capable of detecting whether or not a plurality of substrates accommodated in multiple stages in a container are aligned.

Another object of the present invention is to determine whether or not a board is missing in a container,
An object of the present invention is to provide an inspection apparatus capable of determining an abnormal state such as a tilt of a substrate with high reliability.

[0007]

According to a first aspect of the present invention, there is provided an inspection apparatus for detecting whether or not a plurality of substrates accommodated in multiple stages in a container are aligned. The two sensors that detect the presence or absence of the substrate and output a signal sequence that changes depending on the presence or absence of the substrate, and the two sensors relatively move in a direction crossing the plurality of substrates. Moving means for moving at least one of a container and the sensor; comparing the data of the signal train from the two sensors with the data of a predetermined comparison signal train to arrange and arrange the plurality of substrates; And a determining means for determining whether or not the inspection has been performed.

According to a second aspect of the present invention, there is provided an inspection apparatus for detecting whether or not a plurality of substrates accommodated in multiple levels in a container are aligned. And a moving means for reciprocating the sensor in a direction traversing the plurality of substrates, wherein the sensor is different in the forward path and the return path. Moving means for moving along a route; determining means for comparing the data of the signal sequence from the sensor with data of a predetermined comparison signal sequence to determine whether or not the plurality of substrates are arranged and arranged; And an inspection device characterized by comprising:

[0009]

In the first aspect of the present invention, the moving means may move only the two sensors.

[0010] The data of the comparison signal sequence may be of a plurality of types corresponding to the contents of the inspection.

The data of the comparison signal sequence includes at least one of data of a comparison signal sequence for inspecting the presence / absence of the substrate, for inspecting the overlap of the substrates, and for inspecting the inclination of the substrate. You can also.

[0012] The two sensors may each detect at a different position with respect to the substrate, and the moving means may simultaneously move the two sensors in parallel.

Further, before the determination, there may be provided means for correcting a deviation between the data of the signal train output from each of the two sensors.

Further, the apparatus may further include a position detecting means for detecting a relative position of the sensor with respect to the plurality of substrates.

[0015] The data of the comparison signal sequence may be created based on positional information of each of the boards when the plurality of boards are arranged and arranged in the container.

Further, in the second aspect of the present invention, it is possible to further comprise a position detecting means for detecting a position of the sensor with respect to the plurality of substrates.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a schematic diagram of an inspection apparatus A according to one embodiment of the present invention.

The inspection apparatus A is an apparatus for inspecting whether or not the substrates 102 such as wafers stored in the storage container 100 in multiple stages are arranged and arranged. 1 includes a moving unit 2 for moving the substrate 1 and a computer 3 for determining whether or not the substrates 102 are aligned.

The sensor 1 is, for example, a reflection-type photoelectric sensor that irradiates the end surface of the substrate 102 with light and detects the presence or absence of the substrate 102 based on the presence or absence of the reflected wave. The sensor 1 outputs a signal that changes depending on the presence or absence of the substrate 102. For example, + V when the substrate 102 is detected,
If no signal is detected, a rectangular wave signal sequence that outputs 0 V is output. FIG. 3B is a diagram illustrating a signal train output from the sensor 1 when the sensor 1 is moved with respect to the plurality of substrates 102 as illustrated in FIG. It becomes High when the substrate 102 is detected, and is Low when the substrate 102 is not detected.

FIG. 2 is a diagram showing the arrangement and function of the sensor 1 in detail. In the present embodiment, the sensor 1 is
(1a and 1b). These sensors 1a and 1b are arranged apart from each other in the direction of the substrate surface of the substrate 102 (substantially horizontal direction in the example of the drawing), so that two different positions are viewed with respect to one substrate 102. Make up. The reason why the two sensors 1 are provided to look at one substrate 102 in this manner is to accurately detect a lack, overlap, or inclination of the substrate 102 as described later.

The moving unit 2 is a unit for moving the sensor 1 using a ball screw mechanism, and includes a ball screw 21, a motor 22 for rotating and driving the ball screw 21,
The apparatus includes a nut 23 that moves on the ball screw 21 by the rotation of the ball screw 21, and a support member 24 that is connected to the nut 23 and supports the sensor 1.

In the moving unit 2 having such a configuration, the rotation of the motor 22 causes the nut 23 to move up and down (substantially vertically in the example in the figure), thereby connecting the sensor 1 a with the sensor 1 a via the support member 24. 1b are simultaneously moved in parallel so as to cross each substrate 102 (in a direction perpendicular to the substrate surface), and the sensors 1a and 1b can detect the presence or absence of each substrate 102.

The computer 3 controls the entire inspection apparatus A and determines whether or not the substrates 102 are aligned. The computer 3 controls the motor 22 and controls the movement of the sensor 1 based on a signal from an encoder 25 attached to the motor 22. Note that the movement position of the sensor 1 can be specified by a signal from the encoder 25. The computer 3 receives the signal trains from the sensors 1a and 1b, analyzes the signal trains, and inspects the arrangement state of the substrate 102.

Hereinafter, a specific inspection method will be described with reference to FIG. In the present embodiment, a case where the substrate 102 is accommodated in the container 100 according to the embodiment shown in FIG. 9 will be described as an example.

In the inspection, the computer 3 drives the motor 22 and the sensor 1 to translate the sensor 1a and the sensor 1b in a direction transverse to the substrate 102 as shown in FIG. As a result, based on the signal trains output from the sensors 1a and 1b and the signal from the encoder 25 (used as the movement position information of the sensor 1), the computer 3 detects the sensor 1a as shown in FIG. And the data of the output signal sequence of the sensor 1b. The data of this output signal sequence indicates the presence or absence of the substrate 102 at each position on the path along which the sensors 1a and 1b have moved.
It indicates that the substrate 102 was detected at the time of high and that the substrate 102 could not be detected at the time of low. The data of this output signal sequence can be stored in the memory of the computer 3.

Next, the computer 3 determines whether or not the respective substrates 102 are aligned by comparing the obtained data of the two output signal strings with the data of a predetermined comparison signal string. . In the present embodiment, as shown in FIG. 4, the lack, overlap, and inclination of the substrate 102 are determined using data (gates 1 to 5) of five types of comparison signal strings.

Here, the gate 1 is data at which the substrate 102 is normally disposed at the position where the substrate 102 is normally disposed, and is data for confirming that the substrate 102 is properly disposed. It is. The gate 2 is data obtained by shifting the signal sequence of the gate 1 by one sheet of the substrate 102, and is for determining whether or not the two boards 102 are arranged at the same place. Gate 3
And the gate 4 are for determining whether or not the substrate 102 is disposed at an angle. The gate 5 is an address gate and corresponds between the grooves 101 of the container 100. The gate 5 rises at the same position as the rise of the signal train of the gate 3, and falls at the same position as the fall of the signal train of the gate 4. ing. Note that the data of these comparison signal strings is obtained by determining the position of each board 102 when the boards 102 are normally aligned in the housing 100 based on the design data of the housing 100 and the measured data thereof. It can be calculated and created based on the information on the position, and the computer 3 can store these data in a memory in advance.

Then, at the position where the data of each comparison signal string is High, the computer 3 sets the data of the output signal strings of the sensors 1a and 1b to High or Lo.
It is determined whether or not each of the substrates 102 is aligned and determined based on a combination thereof. FIG. 5 is the determination table.

Referring to FIGS. 4 and 5, for example, FIG.
Of the uppermost substrate 102 (address 1) becomes High with respect to the gate 1 and the gate 5, and is determined to be normally arranged. Further, for example, at the position 111 (address 2) in FIG. 4, the data of the output signal trains of the sensors 1a and 1b are all Low, so that the gates 1 to 5 are all Low, and according to the determination table of FIG. , The substrate 102 is determined to be missing.

Further, for example, at the position 112 (address 3) in FIG. 4, the data of the output signal trains of the sensors 1a and 1b are both High for two substrates 102. The gate 2 and the gate 5 become High, and it is determined that the substrate 102 overlaps.

On the other hand, when the substrate 102 is tilted, determination is made based on two addresses. For example, in the vicinity of 113 on the upper side of FIG.
Is low for all gates, and gate 3 and gate 5 are high at address 6, but for sensor 1b, gate 4 and gate 5 are high at address 5 and any gate at address 6. Is also Low, it can be determined that the substrate 102 is tilted and tilted downward and to the right. Even in the case of tilting to the left, it can be determined in the same manner according to the determination table of FIG.

As described above, according to the inspection apparatus A of the present embodiment, it is possible to detect whether or not a plurality of substrates accommodated in multiple stages in a container are arranged and arranged. It is possible to determine with high reliability not only whether or not there is a defect, but also an abnormal state such as overlapping of the substrates and inclination of the substrates.

Hereinafter, another preferred embodiment of the present invention will be described.

With respect to the inspection apparatus A described above, the sensor 1a
There is no problem when the sensor 1b and the sensor 1b are arranged (horizontally) along the substrate surface of the substrate 102 on which the sensor 1a and the sensor 1b are normally arranged, as shown in FIG. It is also conceivable that they are arranged out of alignment with each other.
In this case, there may be a case where the signal train output from the sensor 1a or 1b does not correspond to the arrangement position of each substrate 102,
In some cases, this may affect the above-described determination and impair the accuracy of the inspection.

Therefore, on the computer 3, the sensor 1a
And 1b may be offset to correct the data of the output signal sequence. FIG. 6B is a diagram showing a mode in which the output signal sequence is offset. FIG. 6 (b)
The signal train on the left side of the sensor 1a as shown in FIG.
FIG. 4 shows output signal trains of the sensors 1a and 1b when the sensors 1a and 1b are arranged with a shift, and it can be seen that there is a shift in the output signal trains between the two. In this case, the computer 3 offsets the data of these output signal trains as shown in the signal train on the right side of FIG. 6 (b) to eliminate the displacement between the sensors 1a and 1b, thereby providing more accurate data. Inspection can be performed. If this offset is adopted, the sensors 1a and 1b do not always need to be moved at the same time.

Next, in the inspection apparatus A described above, the sensor 1
Is composed of two sensors 1a and 1b, but a similar inspection can be performed using one sensor. In this case, the sensor reciprocates in a direction crossing the substrate 102 and moves on different routes between the outward route and the return route.

FIG. 7 is a diagram showing the movement paths of the sensors when inspecting each substrate 102 shown in FIG. 9 using one sensor. The sensor, for example,
The computer 3 moves along the above-described movement path of the sensor 1a, and the computer 3 obtains data of the output signal train. Next, the sensor is moved in parallel, and as the return path, for example, is moved along the movement path of the sensor 1b described above and the computer 3
Obtains the data of the output signal sequence. Thereafter, the computer 3 can perform the above-described inspection based on the data of these output signal strings. Note that such a movement of the sensor can be realized by employing an apparatus in which the above-described moving unit 2 is provided with a mechanism for moving the sensor in parallel from the forward path to the backward path.

Next, in the inspection apparatus A described above, the sensor 1
Although only the movement is performed, the inspection according to the present embodiment can be realized by relatively moving the sensor 1 and the substrate 102 so that the sensor 1 crosses the substrate 102. Therefore, it is needless to say that the sensor 1 may be fixed and the container 100 may be moved, or both the sensor 1 and the container 100 may be moved.

Further, although five types of data are used as the data of the above-described comparison signal sequence, it goes without saying that the number of types is not limited to this.

[0041]

As described above, according to the present invention,
It is possible to detect whether or not a plurality of substrates accommodated in a container in multiple stages are aligned and arranged.In particular, whether or not a substrate is missing, an abnormal state such as overlapping of the substrates and inclination of the substrates Can be determined with high reliability.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of an inspection apparatus A according to an embodiment of the present invention.

FIG. 2 is a diagram showing the arrangement and functions of the sensor 1 in detail.

3A is a diagram illustrating a mode in which the sensor 1 is moved with respect to a plurality of substrates 102. FIG. 3B is a diagram illustrating an output signal sequence of the sensor 1 in this case. is there.

FIG. 4 is a diagram showing output signal trains of sensors 1a and 1b and data of a comparison signal train when the substrate 102 shown in FIG. 9 is inspected.

FIG. 5 is a diagram illustrating a determination table for determining whether the substrates are aligned.

FIG. 6A is a diagram illustrating an example in which the sensors 1a and 1b are displaced from each other, and FIG. 6B is a diagram illustrating data of output signal trains of the sensors 1a and 1b in such a case. FIG. 5 is a diagram showing a mode in which is offset.

FIG. 7 is a diagram illustrating a movement path of a sensor when an inspection is performed using one sensor.

FIG. 8 is an external view of a container 100 that accommodates a substrate 102.

FIG. 9 is a view showing various aspects of the substrate 102 accommodated in the container 100.

Claims (9)

[Claims] 1. An inspection device for detecting whether or not a plurality of substrates accommodated in a container in multiple stages are arranged and arranged, wherein the presence or absence of the substrate is detected, and the presence or absence of the substrate is detected. Two sensors for outputting a changing signal sequence; and moving means for moving at least one of the container and the sensor so that the two sensors relatively move in a direction crossing the plurality of substrates. Determining means for comparing the data of the signal train from the two sensors with the data of a predetermined comparison signal train to determine whether or not the plurality of substrates are arranged and arranged. An inspection apparatus characterized by the above-mentioned. 2. The inspection apparatus according to claim 1, wherein the moving unit moves only the two sensors. 3. The inspection apparatus according to claim 1, wherein a plurality of types of data of the comparison signal sequence correspond to inspection contents. 4. The data of the comparison signal sequence includes at least one of data of a comparison signal sequence for inspecting the presence or absence of the substrate, for inspecting the overlap of the substrates, and for inspecting the inclination of the substrate. The inspection device according to claim 1, wherein: 5. The inspection apparatus according to claim 1, further comprising means for correcting a deviation between the data of the signal train output from each of the two sensors before the determination. 6. The inspection apparatus according to claim 1, further comprising a position detection unit that detects a relative position of the sensor with respect to the plurality of substrates. 7. The data of the comparison signal sequence is created based on positional information of each of the plurality of substrates when the plurality of substrates are arranged and arranged in the container. The inspection device according to item 1. 8. An inspection device for detecting whether or not a plurality of substrates accommodated in a storage container in multiple stages are arranged and arranged, wherein the presence or absence of the substrate is detected, and the presence or absence of the substrate is determined. A sensor that outputs a changing signal sequence; a moving unit that reciprocates the sensor in a direction traversing the plurality of substrates; a moving unit that moves on a different path between the forward path and the return path; and Determining means for comparing the data of the signal sequence with the data of a predetermined comparison signal sequence to determine whether or not the plurality of substrates are arranged and arranged. apparatus. 9. The inspection apparatus according to claim 8, further comprising a position detection unit that detects a position of the sensor with respect to the plurality of substrates.