JP2014232263A - Orientation discrimination device for photomask blank and photomask production device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device capable of, when inputting a photomask blank to a production device, easily discriminating an orientation of the photomask and inputting in an optimal direction.SOLUTION: An orientation discrimination device for a photomask blank discriminates a direction or a front and back of a photomask blank. The orientation discrimination device includes: a stage for mounting a photomask blank; a sensor for detecting a processing portion of each corner part of the photomask blank; and an orientation discrimination part for referring to a pattern table which is information for discriminating an orientation of the photomask blank, according to a detection result of the sensor with regard to the processing portion of each corner part and a location of the processing portion. The sensor is a contact type sensor.

Description

  The present invention relates to a discriminating device for discriminating the top and bottom of a photomask or photomask blanks and a transport device for rotating and reversing the photomask or photomask blanks in a desired direction.

With the recent miniaturization of semiconductor processes, the quality required for photomasks that serve as the originals has become increasingly severe. The photomask is obtained by patterning a chromium thin film on a quartz substrate.

Conventionally, when putting a photomask or photomask blank into a production device, an operator prepares the photomask or photomask blank, distinguishes the top and bottom, changes the direction with a handler, etc. The direction was changed using a device such as.

However, only the conventional visual confirmation or the like causes variations in work by the operator, and sometimes the type and orientation are wrong.

Therefore, in recent years, as a method for discriminating the type of photomask blanks, a photomask blank using a light source device and a light receiver is used by using the processing location, number and shape of notches that are notches in the corners of the photomask blanks. Have been proposed (see, for example, Patent Document 1).

However, in this discriminating device, the angles of the light source device and the light receiver must be adjusted in accordance with the notch cutting angle. In addition, although the prior art can distinguish the front and back of the photomask blanks, it does not mention the top and bottom of the photomask blanks, and even today when using the photomask blanks in production equipment, use a transfer machine, There is a problem that the operator needs to change the direction with a handler or the like.

JP 2005-221705 A

  Accordingly, the present invention is intended to solve such problems of the prior art. When a photomask or photomask blank is inserted into a production apparatus, the direction is easily determined and the appropriate direction is inserted. It is an object of the present invention to provide a device that can be used.

As means for solving the above-mentioned problems, the invention of claim 1 is an orientation discriminating apparatus for discriminating the orientation and front and back of a photomask blank, comprising a stage for placing the photomask blank, and the photomask blank A pattern for detecting information on the front and back and the orientation of the photomask blanks according to the detection result of the sensor and the position of the processing part with respect to the processing part of each corner part. The photomask blank direction discriminating apparatus is characterized by comprising a direction discriminating unit that collates a table and discriminates the front and back sides and the direction, and the sensor is a contact type sensor.

  According to a second aspect of the present invention, in the photomask blank orientation determination apparatus according to the first aspect, the contact sensor is provided at every corner of the photomask blank.

  According to a third aspect of the present invention, the sensor is provided at one corner of the photomask blank, and each time the stage rotates 90 °, the sensor inspects each corner and rotates 360 °. 2. The photomask blank orientation determination apparatus according to claim 1, wherein the stage is rotated by 90 [deg.] To inspect all corners.

  According to a fourth aspect of the present invention, in the photomask blank orientation determination apparatus according to the first aspect, the sensor is provided at two opposite corners of the photomask blank.

  According to a fifth aspect of the present invention, there is provided the photomask blank orientation determination device according to any one of the first to fourth aspects and a device for rotating and reversing the photomask blank based on the determination result. It is the photomask production apparatus characterized.

  In the present invention, the sensor is in contact with an arbitrary position of the photomask or photomask blanks placed on the stage and regulated by the position regulating pin, and the machining location can be recognized by the machining location detected by the sensor. The top and bottom of the mask or photomask blanks can be discriminated and put into each production apparatus in an appropriate direction.

It is a schematic top view which shows an example of the direction discrimination | determination apparatus of the photomask or photomask blanks of this invention. It is a schematic sectional drawing which shows an example of the direction discrimination | determination apparatus of the photomask or photomask blanks of this invention. It is explanatory drawing which shows the interface of the orientation determination apparatus of the photomask or photomask blanks of this invention. It is a figure which shows an example of a pattern table. It is explanatory drawing which shows the concept of corner circulation. It is a flowchart which shows an example of the processing flow of the orientation discrimination | determination apparatus of a photomask or a photomask blank. It is a flowchart which shows an example of the process flow of direction determination of a photomask or a photomask blank. It is a schematic top view which shows an example of the orientation discrimination | determination apparatus of the photomask which concerns on Embodiment 2, or a photomask blank. It is a schematic sectional drawing which shows an example of the orientation discrimination | determination apparatus of the photomask which concerns on Embodiment 2, or a photomask blank. It is a schematic top view which shows an example of the orientation discrimination | determination apparatus of the photomask which concerns on Embodiment 3, or a photomask blank. It is a schematic sectional drawing which shows an example of the direction discrimination | determination apparatus of the photomask which concerns on Embodiment 3, or a photomask blank.

Embodiments of the photomask or photomask blank orientation determination device of the present invention will be described below.
[Embodiment 1]
(Device configuration)

The orientation of the photomask or photomask blank according to claim 2, comprising a stage 4 on which the photomask or photomask blank is placed, a positioning pin 3 for regulating the position of the photomask, and a contact sensor 5 for the processing location 2. A discrimination device will be described (see FIGS. 1 and 2). With this configuration, the contact sensor 5 comes into contact with an arbitrary position of the photomask or photomask blanks regulated by the positioning pins 3, and the orientation can be determined based on whether or not the processing location 2 is detected.

FIG. 1 is a schematic top view illustrating an example of a photomask or photomask blank orientation determination apparatus. FIG. 2 is a schematic cross-sectional view of a photomask or photomask blank orientation determination apparatus. In the figure, 1 is a photomask or photomask blanks, 2 is a processed portion where a corner portion of the photomask or photomask blanks is chamfered to form a notch, 3 is a positioning pin, 4 is a photomask or photomask blank placed Stages 5 and 5 indicate contact sensors for inspecting and detecting whether or not each corner portion is processed.

The operation of the photomask or photomask blank orientation determination apparatus of the present invention configured as described above will be described below.

First, the positioning pins 3 are installed on the stage 4, and the photomask or the photomask blanks 1 is placed on the stage so as to contact the positioning pins 3 (see FIG. 2).

A contact sensor 5 is installed at an arbitrary position of the stage 1 (see FIG. 2). The contact-type sensor 5 is fixed at a position where it can come into contact with the processing location 2 of the photomask or photomask blank. By recognizing the presence / absence of the processed portion 2 in contact with each contact type sensor 5, the orientation of the photomask or photomask blank can be determined.
(Determination part)

In the following, the orientation discriminating unit of the photomask or photomask blank orientation discriminating apparatus will be described. The orientation determination unit of the photomask or the photomask blank can be configured by a computer, for example. However, the present invention is not limited to this, and other arithmetic devices may be used.

  FIG. 3 is an explanatory diagram showing an interface of a photomask or photomask blank orientation determination unit. The photomask or photomask blank orientation determination unit inputs a detection result from the contact sensor 5 shown in FIG. 2 and performs processing. The detection result is the presence / absence of the processing portion 2 in a state of contact with the contact sensor 5. At the time of processing, the detection result is collated with the information in the pattern table as shown in FIG. 4, and the result of determining the orientation of the photomask or photomask blank is output.

  FIG. 4 is a diagram illustrating an example of a pattern table. In this example, since the contact points of the contact sensor 5 are four corners, one contact sensor 5 is provided at each corner, and a total of four contact sensors 5 are provided. For each orientation of the photomask or photomask blank, the detection result of the contact sensor 5 at the first corner (corresponding to the processing location 1), the detection result of the contact sensor 5 at the second corner (corresponding to the processing location 2), A pattern composed of the detection result of the contact sensor 5 at the three corners (corresponding to the processing location 3) and the detection result of the contact sensor 5 at the fourth corner (corresponding to the processing location 4) is defined and stored. The pattern table is configured to be read by a photomask or photomask blank orientation determination unit. For example, it is stored in a storage area in the computer.

  In FIG. 4, the top is described as celestial, for example, in the case of a photomask, the state where the formed pattern is upright when viewed from the film surface on which the thin film is formed, and the bottom is described as celestial. What is being formed is a state in which the formed pattern is inverted or rotated by 180 °, and the right is described as celestial, because the formed pattern is upright from the state in which it is upright. It can be defined that the state in which it is rotated and the left side is described as celestial is the state in which the formed pattern is upright from 270 ° to the right or 90 ° to the left. Photomask blanks can also be defined in the same manner as a photomask by assuming a pattern to be formed.

However, since the photomask or the photomask blank 1 is not necessarily installed in a predetermined direction, the detection pattern of the relationship (corner circulation) obtained by rotating the above detection pattern by 90 degrees, 180 degrees, and 270 degrees is also suitable. This is handled as a detection pattern (see FIG. 5).

  FIG. 5 is a diagram showing the concept of corner circulation. The detection result of the first corner is treated as the detection result of the second corner, the detection result of the second corner is treated as the detection result of the third corner, the detection result of the third corner is treated as the detection result of the fourth corner, and the fourth By treating the corner detection result as the first corner detection result, a detection pattern having a relationship rotated by 90 degrees is obtained.

Also, the detection result of the first corner is treated as the detection result of the third corner, the detection result of the second corner is treated as the detection result of the fourth corner, the detection result of the third corner is treated as the detection result of the first corner, By treating the detection result of the fourth corner as the detection result of the second corner, a detection pattern having a relationship rotated by 180 degrees is obtained.

Also, the detection result of the first corner is treated as the detection result of the fourth corner, the detection result of the second corner is treated as the detection result of the first corner, the detection result of the third corner is treated as the detection result of the second corner, By treating the detection result of the fourth corner as the detection result of the third corner, a detection pattern having a relationship rotated by 270 degrees is obtained.

Regardless of this example, all of the detected patterns rotated 90 degrees, 180 degrees, and 270 degrees may be stored in the pattern table.
(Discrimination process)

  FIG. 6 is a flowchart illustrating an example of a processing flow of the photomask or photomask blank orientation determination apparatus. The detection result of each sensor is input, and the photomask or photomask blank orientation determination processing is performed by the photomask or photomask blank orientation determination unit.

  FIG. 7 is a flowchart showing an example of a processing flow for determining the orientation of a photomask or photomask blank. It is determined whether the detection result of each contact sensor matches the pattern in the pattern table. The detection result is handled as the presence of a machining location when the contact sensor detects the machining location. If it matches any of the patterns, the direction corresponding to the matched pattern is output.

If they do not match any pattern, they are rotated in order 90 degrees, 180 degrees, 270 degrees as described above. If they still do not match, the photomask or photomask blank is inverted and rotated in the same manner. Matching is also performed for the detection pattern of the relationship.

As described above, the orientation of the photomask or photomask blank is determined by touching an arbitrary position of the photomask or photomask blank and comparing the pattern with the presence / absence of the processing location 2 and corresponding to the pattern when matching. The photomask or photomask blank direction is output.

By processing in this way, the orientation of the photomask or photomask blank can be determined from the detection result.
[Embodiment 2]

In the first embodiment, four contact sensors 5 are provided at each corner, and the direction of the photomask or photomask blanks is distinguished depending on which of the contact sensors detects, but one contact sensor is used. In addition, it is possible to distinguish a processing place by contacting an arbitrary position and distinguishing the detected place. In the second embodiment, one contact type sensor is provided, the contact points are four corners, the stage is rotated by 90 degrees, and the contact is made each time the rotation is performed.

  FIG. 8 is a schematic top view showing an example of the orientation determination device for the photomask or photomask blank 1 according to the second embodiment. FIG. 9 is a schematic cross-sectional view showing an example of the orientation determination device for the photomask or photomask blank 1 according to the second embodiment. The rotation shaft 6 is rotated by a control motor or the like, and the stage can be stopped at a predetermined angle.

First, in a non-rotating state (0 degree state), the first corner is contacted to obtain a detection result. Subsequently, it is rotated 90 degrees (90-degree state), contacts the second corner, and a detection result is obtained. Next, it is further rotated 90 degrees (180 degree state), and contacts the third corner to obtain a detection result. Finally, it is further rotated 90 degrees (270 degree state), and contacts the fourth corner to obtain a detection result. If the processed portion 2 is still not detected, the photomask or photomask blank 1 is reversed and rotated in the same manner as described above to obtain a detection result. As described above, a detection result similar to that of the first embodiment can be acquired.
[Embodiment 3]

In the third embodiment, an embodiment according to claim 4 will be described in which the position of one contact-type sensor is rotated by 90 degrees and contact is made each time the rotation is performed. In this example as well, the direction is distinguished according to the detected machining location in the same manner as described above.

  FIG. 10 is a schematic top view showing an example of the orientation determination device for the photomask or photomask blank 1 according to the third embodiment. FIG. 11 is a schematic cross-sectional view showing an example of a photomask or photomask blank orientation determination apparatus according to the third embodiment. By rotating the rotating shaft 6 with a control motor or the like, the sensor installation base 9 can be stopped at a predetermined angle.

First, in a non-rotating state (0 degree state), the first corner is contacted to obtain a detection result. Subsequently, it is rotated 90 degrees (90-degree state), contacts the second corner, and a detection result is obtained. Next, it is further rotated 90 degrees (180 degree state), and contacts the third corner to obtain a detection result. Finally, it is further rotated 90 degrees (270 degree state), and contacts the fourth corner to obtain a detection result. If the processed portion 2 is still not detected, the photomask or photomask blank 1 is reversed and rotated in the same manner as described above to obtain a detection result. Thereby, the detection result similar to Embodiment 2 is acquirable.

  It is desirable that a part or all of the material constituting the contact sensor described in Embodiments 1 to 3 is a material that does not damage the photomask or the photomask blank 1 and does not attach and generate foreign matter.

Examples of the present invention will be specifically described below, but the present invention is not limited thereto.
<Example 1>
An example of the present invention using the first embodiment described in claim 2 will be described in the case where photomask blanks are used.
(sensor)
A total of four contact sensors 5 were installed, one at each corner of the photomask blank. Each contact-type sensor 5 was installed so that it could contact | connect perpendicularly with the chamfered surface which is a process location in a corner.
(Configuration of photomask blanks)
A round corner type notch was formed as a processing location 2 at one location on the back side of the corner of a 6-inch square, 3 mm thick quartz substrate for photomask blanks. The notch is a chamfered portion formed on the back surface of the corner of the quartz substrate for photomask blanks.

  An example will be described in which photomask blanks are introduced into a photomask production apparatus equipped with the orientation discrimination device of the present invention. In this example, when the film surface faces upward and the notch is on the upper right, the top of the photomask blank is set as the top. By deliberately changing the photomask blanks into a direction with the film surface up and the celestial right, and with the film surface down and the celestial down direction, the photomask blanks are loaded into the photomask production equipment, respectively. The direction to enter the mask production equipment was investigated.

When the film surface is on and the top is on the right side, the contact sensor does not detect the processing location at the first contact, the photomask blank is inverted by the reversing device, and the processing location is detected at the second contact. Then, the photomask blank was rotated and inverted in an appropriate direction registered in advance in the apparatus. When the film surface is below and the top is below, the processing location is detected by the first contact, and in this case as well, the photomask blanks are rotated and inverted in the appropriate orientation registered in the photomask production device in advance. It was thrown in.
<Example 2>

The Example of this invention using Embodiment 2 of Claim 3 is demonstrated. The used photomask blanks are the same as those in Example 1.
(Contact type sensor)
A contact sensor was installed at one corner of the photomask blank. The contact type sensor was installed so that it could contact perpendicularly to the chamfered surface, which is the processing location at the corner.
(stage)
The stage on which the photomask blanks are placed is provided with positioning pins so that the photomask blanks are always placed at the same position on the stage. The stage can be rotated 90 ° at a time in the clockwise direction.

The direction of the photomask blank was intentionally changed in the same manner as in Example 1, and the photomask blank was put into a photomask production apparatus, and the direction into the apparatus was examined.

When the film surface is on top and the top is on the right, the stage is rotated 90 ° four times with the film surface facing up, and the processing location is detected by the contact sensor after each 90 ° rotation. The contact type sensor after the 7th rotation which did not detect the processing part, but reversed the photomask blanks by the reversing device to bring the film surface down, and rotated the photomask blanks 90 ° twice more The machining location was detected by detection by. The photomask blanks were rotated and inverted in an appropriate direction registered in advance in the apparatus. When the film surface was down and the top was down, the photomask blank was rotated, and the processing location was detected by contact of the contact sensor for the second time. Also in this case, the photomask blanks were rotated and reversed in an appropriate direction registered in advance in the apparatus.

In Example 2, the rotation direction of the stage was clockwise. Similarly, when the rotation direction of the stage was counterclockwise, the photomask blank was rotated and reversed in an appropriate direction to the apparatus. .
<Example 3>

The Example of this invention using Embodiment 3 of Claim 4 is demonstrated. The used photomask blanks are the same as those in Example 1.
(sensor)
A contact sensor was installed at one corner of the photomask blank. The contact type sensor was installed so that it could contact perpendicularly to the chamfered surface, which is the processing location at the corner. Initially, it was installed in contact with the first corner of FIG. The contact sensor can be rotated 90 ° around the stage in a clockwise direction at a time.

The direction of the photomask blanks was intentionally changed in the same manner as in Example 1, and the photomask blank was put into a photomask production apparatus, and the direction into the apparatus was examined.

When the film surface is on the top and the top is on the right, the contact surface sensor is rotated 90 ° four times around the stage and the machining location is detected. Inverting the photomask blanks with a reversing device to bring the film surface down, and detecting the processing location by rotating the contact sensor twice 90 ° and detecting the processing location The photomask blanks were rotated and inverted in an appropriate direction registered in advance in the apparatus. When the film surface is below and the top is below, the contact sensor rotates to detect the processing location by the second detection, and the photomask blank is also in the appropriate orientation registered in advance in this case. It was rotated and reversed.

In Example 3, the rotation direction of the contact sensor was clockwise. Similarly, when the rotation direction of the contact sensor is counterclockwise, the photomask blank is rotated and reversed in a direction suitable for the apparatus. It was thrown in.

The photomask blank has been described above as an example, but the same result is obtained when a photomask is used.

DESCRIPTION OF SYMBOLS 1 Photomask or photomask blank 2 Processing location 3 Positioning pin 4 Stage 5 Contact type sensor 6 Rotating shaft 7 Stage rotation direction 8 Sensor rotation direction 9 Sensor installation stand

Claims (5)

  An orientation discriminating apparatus for discriminating the orientation and front / back of a photomask blank, a stage for placing the photomask blank, a sensor for detecting a processing portion of each corner portion of the photomask blank, and An orientation discriminating unit that discriminates the front and back sides and the orientation by collating a pattern table that is information for discriminating the front and back sides and the orientation of the photomask blanks according to the detection result of the sensor and the position of the machining location on each corner part An apparatus for discriminating the orientation of photomask blanks, wherein the sensor is a contact sensor.   The photomask blank orientation determination apparatus according to claim 1, wherein the contact sensor is provided at every corner of the photomask blank.   The sensor is provided at one corner of the photomask blank. Each time the stage rotates 90 °, the sensor inspects each corner and the stage rotates 90 ° until it rotates 360 °. 2. The photomask blank orientation determination apparatus according to claim 1, wherein all corners are inspected.   2. The photomask blank orientation determination apparatus according to claim 1, wherein the sensor is provided at two opposite corners of the photomask blank.   5. A photomask production apparatus comprising: a photomask blank orientation determination device according to claim 1; and a photomask blank rotation / reverse device based on the determination result.

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