JPH0951028A - Photomask management system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To automatically manage storage and inspection of reticule. SOLUTION: A storage room 11 wherein reticules 1 are identified with identification codes attached to an individual reticle for storing in a specified place, respectively, a foreign matter inspection device 20 inspecting a foreign matter of each reticule and then outputting the result, and a delivery device 35 which communicates both 11 and 20 with a communication passage 36 for delivering the reticules, are provided, and, the storage room, the foreign matter inspection device and the delivery device are so constituted as to be generalize-controlled with a generalization controller 40. So that, at the foreign matter inspection of reticules stared in the storage room, since the reticules are transferred from the storage room to the foreign matter inspection device with the delivery device, the foreign matter inspection of the stored reticules is automatically perforated with precision without interposition of a person, so that the reticules are always maintained normal. By staring foreign matter inspection data, and collating data of the same reticules, the data are utilized, so that precision of inspection of the foreign matter inspection device is raised.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photomask management system, and more particularly to a photomask management system in the case where a large number of types of photomasks are used while being frequently replaced on the same production line. In the process, a desired pattern is formed on a semiconductor wafer (hereinafter,
It is called a wafer. A) effective to manage the reticle as a magnifying photomask used to transfer to.

[0002]

2. Description of the Related Art A reticle, which is an enlarged photomask, is widely used as a photomask used for transferring a desired pattern onto a wafer in a manufacturing process of a semiconductor device which is highly integrated and miniaturized. . Since this reticle is a photomask obtained by enlarging a part of a desired pattern, a plurality of types of reticles will be used to manufacture the same semiconductor device. In addition, since the recent semiconductor device production mode has been progressing in high-mix low-volume production, the types and number of reticles managed on the production line are extremely large. Therefore, each reticle is provided with a unique identification code for identifying each reticle.

On the other hand, in a semiconductor device manufacturing factory, a stepper, which is an exposure device for transferring the pattern of a reticle onto a wafer, is extremely expensive, and therefore one stepper cannot be prepared for each enormous reticle. Therefore, the reticle is frequently replaced with the stepper, and a large number of waiting reticles are stored in the storage. In the conventional reticle storage, a storage rack and a transfer robot are installed in a clean bench that maintains a high degree of cleanliness. The transfer robot is configured to store each reticle in a designated location on the storage rack, and is also configured to retrieve the reticle designated by the identification code from the designated storage location.

If foreign matter adheres to the reticle,
Since the image of the foreign matter is transferred to the wafer as a defect,
Generally, a reticle stored in a storage is inspected for foreign matter regularly or irregularly by a foreign matter inspection apparatus as a defect inspection apparatus. A conventional foreign matter inspection apparatus is configured to detect a foreign matter attached to a reticle by irradiating a reticle with a laser and detecting scattered light from the foreign matter.

Conventionally, when a foreign substance inspection device performs a foreign substance inspection on a reticle stored in a storage, the worker designates the reticle to be subjected to the foreign substance inspection with an identification code and leaves the storage. And put it in the foreign matter inspection device. When the result of the foreign matter inspection is normal, the reticle is put into the storage by the worker and stored at the designated place in the storage.

[0006] As an example in which a reticle foreign matter inspection device is described, Japanese Patent Laid-Open No. 4-45863 and Hit,
achi Review Vol. 40 (1991) N
o. 6 P395-P400 and Hitachi
Hyoron68 P731-P736.

[0007]

However, in the conventional reticle management system, when the foreign substance inspection device performs the foreign substance inspection on the reticle stored in the storage, the reticle which should be subjected to the foreign substance inspection is operated. Since the person specifies the identification code and puts it out of the storage cabinet and puts it in the foreign substance inspection apparatus, not only the efficiency of the inspection work is low, but also a damage accident etc. when transferring the reticle from the storage cabinet to the foreign matter inspection apparatus. It has been clarified by the present inventor that there is a problem that the period of the periodic inspection varies and that the inspection result data is not fully utilized in the management of the reticle.

An object of the present invention is to provide a photomask management system capable of automatically managing storage and defect inspection of photomasks.

The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

[0010]

The outline of a typical invention among the inventions disclosed in the present application is as follows.

That is, the photomask management system is
A storage box that identifies a plurality of photomasks by the identification code attached to each photomask and stores each in a predetermined place, a defect inspection device that inspects each photomask for defects and outputs the inspection result, and a storage The storage device, the defect inspection device, and the delivery device for delivering the photomask to each other are provided. The storage device, the defect inspection device, and the delivery device are connected to a general controller and are configured to be integrally controlled. It is characterized by being

[0012]

According to the above-mentioned means, when the defect inspection of the photomask is carried out, the desired photomask identification code is designated in the storage. The storage takes out the photomask of the specified identification code from a predetermined storage location and automatically carries it into the defect inspection device by the delivery device. When the defect inspection device performs a defect inspection on the photomask, the inspection result data is transmitted to the overall controller. The overall controller stores the transmission data in the memory and manages it. For example, if the inspection result of the photomask is normal, the general controller causes the delivery device to store the photomask in the storage and store it in the original designated place of the storage.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 schematically shows a reticle management system which is an embodiment of the present invention, (a) is a perspective view of a defect,
(B) is a perspective view of a main part. 2 is a plan sectional view thereof, and FIG. 3 is a front sectional view thereof. FIG. 4 is a flow chart for explaining the operation. FIG. 5 is an explanatory diagram showing an example of how to utilize the inspection data.

In the present embodiment, the photomask management system according to the present invention is constructed as a reticle management system that stores and automatically manages a reticle that is an enlarged photomask. Reticle 1 that is the object of storage management
The pattern forming surface is protected by a pellicle (not shown), and in order to prevent contamination due to adhesion of foreign matter, the pellicle is housed in each case 2 and conveyed between the processes. . Further, each reticle 1 is provided with a unique identification code (not shown) for uniquely identifying each reticle 1, and the unique identification code is assigned to each reticle 1 depending on the form such as a numeral, an alphabetic character or a bar code. It is displayed on the surface of Case 2.

Incidentally, the reticle 1 is a substantially square plate-like object in which a pattern is formed on a blank made of quartz glass by using a metal material such as chrome, and the case 2 for housing the reticle 1 is made of resin or the like. A material having an appropriate rigidity, such as metal, is used, and has a square flat box shape slightly larger than the reticle 1. The case 2 is formed as an airtight box that can prevent foreign matter such as dust from entering, and is configured so that the reticle 1 can be stored in and taken out freely.

Reticle management system 10 according to the present embodiment
Is a storage box 11 for identifying a plurality of reticles 1 by their respective identification codes and storing them in predetermined places.
A foreign matter inspection device 20 as a defect inspection device for performing a foreign matter inspection of each reticle and outputting the inspection result; and a delivery device 35 for handing over the reticle 1 between the storage 11 and the foreign matter inspection device 20. , The storage 11, the foreign substance inspection device 20, and the delivery device 35. The storage box 11 and the foreign matter inspection apparatus 20 are installed next to each other, and a space between them is connected by a delivery apparatus 35.

The storage 11 is equipped with a clean bench 12 whose cleanliness is kept constant.
2 has a plurality of storage shelves 13 and a transfer robot 1 in the room.
4 are installed. Each of the storage shelves 13 is configured to horizontally store and store a plurality of reticles 1, which are storage objects, in a state of being stored in the case 2. In this embodiment, the transfer robot 14 is configured by using an articulated robot, and the grip 16 of the arm 15 is used.
With this, the case 2 is gripped and the reticle 1 is conveyed while being stored in the case 2. Also,
The transfer robot 14 includes a controller (not shown) constructed from a computer or the like. The controller is configured to store the case 2 accommodating each reticle 1 in a designated location on the storage shelf 13, and to retrieve the reticle 1 designated by the identification code from the designated storage location. Has been done.

An inlet / outlet port 17 is opened on the front wall of the clean bench 12 so as to communicate with the inside and outside of the clean bench 12, and the inlet / outlet port 17 is an air curtain for preventing dust and the like from entering during the in / out operation. A dustproof device (not shown) such as is installed. A storage / receipt receiving rack 18 is installed at a portion of the clean bench 12 facing the storage / receipt / exit opening 17. Further, a communication port 19 is opened in the side wall of the clean bench 12 so as to communicate with the inside and outside of the clean bench 12, and the communication port 19 is provided with a communication passage described later.

The foreign matter inspection device 20 as a defect inspection device is provided with a clean bench 21 whose cleanliness is kept constant, and an optical inspection device and a transfer robot are installed in the room of this clean bench 21. The optical inspection device 22 is a table 23 that horizontally holds the reticle 1 as an inspection object and moves it in the XYZ and θ directions, and an irradiation device that irradiates the reticle 1 held on the table 23 with inspection light 24 such as a laser. 25 and the foreign matter 3 of the inspection light 24
And a photodetector 27 for detecting the scattered light 26 in FIG.
Further, the foreign matter inspection device 20 includes a controller 28 constructed from a computer or the like. The controller 28 is configured to determine a foreign substance based on an electric signal from the light receiver 27 and store the determination result in a memory (not shown) in association with the identification code given to the reticle 1. .

In this embodiment, the transfer robot 29 is constructed by using an articulated robot, and the arm 30 is used.
The case 2 is gripped by the grip 31 of the reticle 1
While being transported while being stored in the case 2,
The reticle 1 can be taken in and out of the case 2 by opening and closing the case 2.

An entrance / exit port 32 is also provided on the front wall of the clean bench 21 of the foreign matter inspection apparatus 20 so as to communicate with the inside and outside of the clean bench 21, and the entrance / exit port 32 allows dust and the like to enter during the entry / exit work. A dustproof device (not shown) such as an air curtain for preventing the above is installed. A storage / receipt receiving rack 33 is installed at a portion of the clean bench 21 facing the storage / receipt / exit 32. Also, clean bench 21
A communication port 34 is provided on a side wall of the storage chamber 11 opposite to the storage chamber 11 so that the inside and outside of the clean bench 21 communicate with each other.
It is continuously provided so as to communicate with the side communication port 19.

The delivery device 35 is provided with a communication passage 36 that connects the communication port 19 on the side of the storage 11 and the communication port 34 on the side of the foreign matter inspection device 20 which are adjacent to each other and face each other. The communication passage 36 is airtight. It is configured so that it can be maintained and dust and the like can be prevented from entering. The communication passage 36 is provided with a delivered article detection device 37 including a light projector 38 and a light receiver 39, and the detection device 37 is configured to transmit a detection signal to the overall controller 40. The overall controller 40 is constructed from a computer or the like, and includes the transfer robot 14 of the storage 11, the foreign matter inspection device 2
It is electrically connected to the controller 28 of 0 and the delivered article detection device 37 of the delivery device 35, etc., and controls the storage 11, the foreign substance inspection device 20, and the delivery device 35 based on signals from them. Is configured.

Next, the operation will be described. For example, when a new reticle is received at a semiconductor device manufacturing factory, the new reticle 1 is stored in the foreign matter inspection apparatus 20 through the storage / reception port 32 while being stored in the case 2. The transfer robot 29 of the foreign matter inspection device 20 takes out the reticle 1 from the case 2 placed on the receiving / delivering receiving rack 33 and transfers the reticle 1 onto the table 23 of the optical inspection device 22. The irradiation device 25 of the optical inspection device 22 irradiates the reticle 1 with the inspection light 24. At this time, the table 23 scans the inspection light 24 relative to the reticle 1 by moving the reticle 1 in the XY directions. Inspection light 24 is foreign matter 3
When the foreign substance 3 is irradiated with the scattered light 26, the scattered light 26 is received by the light receiver 27. Based on the relationship between the reception of the scattered light 26 and the scanning of the table 23, the controller 28 identifies the adhesion position of the foreign matter 3 on the reticle 1 by coordinates and stores it in the memory in association with the identification code of the reticle 1. Further, the controller 28 determines whether the foreign matter inspection of the reticle 1 is normal or abnormal.

The reticle 1 which has been judged to be normal by the foreign matter inspection as the defect inspection as described above,
It is returned to the case 2 by the robot 29. The reticle 1 stored in the case 2 is transferred to the communication passage 36 of the delivery device 35 by the robot 29. When the reticle 1 is carried into the communication passage 36 from the communication port 34 on the foreign substance inspection device side, the delivered article detection device 37 detects the carry-in, and the detection signal is transmitted to the overall controller 40. The general controller 40 commands the transfer robot 14 of the storage 11 to receive the work.

The transfer robot 14, which has received the instruction of the receiving work, receives the reticle 1 in the communication passage 36 of the delivery device 35 in the case 2 as it is and stores it in the storage box 11.
It is transferred to a designated place on the storage shelf 13 of. The transport robot 14 stores the identification code of the reticle 1 and the storage location in a memory (not shown) in association with each other.

Next, the reticle 1 stored in the storage 11
The case where the periodical foreign substance inspection is performed will be described with reference to the flowchart shown in FIG.

For example, when a predetermined period has passed after storage,
The identification code of the reticle 1 to be regularly inspected is designated from the general controller 40 to the transfer robot 14 of the storage 11. The transport robot 14 searches the place where the reticle 1 designated for the periodic inspection is stored, takes out the designated reticle 1 in the case 2 and transports it to the communication passage 36 of the delivery device 35.

When the case 2 accommodating the reticle 1 is transferred to the communication passage 36 of the delivery device 35 and a detection signal is transmitted from the delivered article detection device 37, the general controller 40 causes the transfer robot of the foreign matter inspection device 20 to operate. 29 is instructed to carry to the table 23. The transfer robot 29 transfers the case 2 to the storage / reception tray 33, and
The reticle 1 is taken out from the table and transferred to the table 23.
When the reticle 1 is transferred to the table 23, the foreign substance inspection work as the defect inspection work is performed by the optical inspection device 22 in the same manner as described above.

Foreign matter inspection apparatus 2 for this reticle 1
When the foreign matter inspection of this time by 0 is completed, the general controller 40 calls the foreign matter inspection result of this time from the memory of the foreign matter inspection device 20, and also the previous inspection result data regarding this reticle 1 stored in the memory of the overall controller 40. Search and perform the operations shown in FIG. That is, the previous foreign matter data shown in (b) and (c) is subtracted from the current foreign matter data shown in (a). The difference in the overall controller 40 is
If it is an increase as shown in (d), it is determined as a failure, and if it is not an increase as shown in (e), it is determined as a pass.

When the overall controller 40 determines that the reticle 1 has passed, it updates the foreign matter inspection data for the reticle 1 and stores the reticle 1 in the case 2 by the transfer robot 29 of the foreign matter inspection apparatus 20 and transfers it to the delivery apparatus 35. Transport.

When the case 2 accommodating the reticle 1 is transferred to the communication passage 36 of the delivery device 35 and the detection signal is transmitted from the delivered article detection device 37, the general controller 40 causes the transfer robot 14 of the storage box 11 to move. Storage shelves 13
To transfer to. The transport robot 14 transports the inspected normal reticle 1 to the original designated place of the storage shelf 13 and stores the reticle 1 in the state of being housed in the case 2.

On the other hand, if the general controller 40 determines that the reticle 1 is rejected, the reticle 1 is stored in the case 2 of the receiving / receiving rack 33 of the foreign substance inspection device 20 by the transfer robot 29 of the foreign substance inspection device 20. The rejected reticle 1 of the storage / receipt receiving rack 33 is stored in the case 2 by the operator from the storage / accommodation port 32, and the confirmation test of the rejection is executed. By the way, this confirmation inspection is carried out by visual inspection using an optical microscope or the like.

When it is determined by this confirmation inspection that the previous automatic foreign matter inspection is an erroneous detection, the reticle 1 is stored in the case 2 and the entrance / exit port 3 of the foreign matter inspection apparatus 20 is stored.
Returned to 2.

On the other hand, if it is determined by this confirmation inspection that the previous automatic foreign matter inspection is not an erroneous detection, the reticle 1
Are sent to the cleaning process and cleaned. The cleaned reticle 1 is returned to the loading / unloading port 32 of the foreign matter inspection apparatus 20 while being housed in the case 2.

If it is determined that the reticle 1 is rejected even if this reject routine is repeated several times, the overall controller 40 determines that the reticle 1 is defective, and issues an instruction to remake the reticle 1.

By sequentially performing the above-mentioned work for each reticle 1 stored in the storage 11,
For all the reticles 1 stored in the storage 11, a foreign matter inspection as a defect inspection is regularly carried out.

According to the above embodiment, the following effects can be obtained. (1) By installing a delivery device between the storage and the foreign substance inspection device, the reticle can be transferred from the storage device to the foreign substance inspection device by the delivery device when the reticle stored in the storage is regularly or irregularly inspected. Therefore, the reticle stored in the storage can be automatically inspected for foreign matter because it can be automatically transferred.

(2) By centrally controlling the storage, the foreign matter inspection device and the delivery device by the general controller, periodical foreign matter inspection of the reticle can be automatically and accurately performed without human intervention. Because you can
The reticle stored in the storage can always be maintained in a normal state, and as a result, the manufacturing yield of semiconductor devices and the productivity can be improved.

(3) Further, by changing the control conditions for the overall controller, it is possible to easily change the period for carrying out the periodic inspection and to carry out the irregular sampling inspection. It can be maintained even more normal.

(4) The inspection result data of the foreign substance inspection device can be fully utilized by storing the inspection result data of the foreign substance inspection device and comparing the present data with the past data by the general controller. At the same time, the accuracy of the inspection of the foreign substance inspection apparatus can be further enhanced, so that the reticle to be stored in the storage and the reticle currently stored in the storage can be maintained more normal.

The invention made by the present inventor has been specifically described based on the embodiments, but the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the invention. Needless to say.

For example, the specific configurations of the storage shelves, the transfer robots, the loading / unloading ports, etc. in the storage are not limited to those in the above-mentioned embodiment, but can be appropriately changed according to the storage conditions, the loading / unloading conditions, and the like.

The defect inspection apparatus is not limited to be configured to perform only foreign matter inspection, but may be configured to perform appearance defect inspection, dimension inspection, etc. for white defects and black defects of a pattern.

The specific structure of the delivery device is not limited to the above embodiment.

In the above description, the case where the invention made by the present inventor is mainly applied to the reticle management system which is the background field of application has been described.
The invention is not limited to this, and can be applied to a one-to-one photomask management system. Further, the invention can be applied not only to a semiconductor device manufacturing factory but also to a photomask management system in a photomask manufacturing factory.

[0046]

The effects obtained by typical aspects of the invention disclosed in the present application will be briefly described as follows.

A delivery device is installed between the storage and the defect inspection device, and the storage controller, the defect inspection device, and the delivery device are centrally controlled by a general controller, so that the photomask stored in the storage can be stored. In case of regular inspection or irregular inspection of the photomask, the photomask can be transferred from the storage to the defect inspection device by the delivery device, and the periodical inspection of the photomask can be automatically and accurately performed without human intervention. Therefore, the photomask stored in the storage can be always maintained in a normal state, and as a result, the manufacturing yield of semiconductor devices and the productivity can be improved.

Further, by storing the inspection result data of the defect inspection apparatus and comparing the present data with the past data by the general controller, the inspection result data of the defect inspection apparatus can be utilized and the defect can be utilized. Since the accuracy of the inspection of the inspection device can be further improved, the photomask to be stored in the storage and the photomask currently stored in the storage can be maintained more normally.

[Brief description of drawings]

FIG. 1 schematically shows a reticle management system that is an embodiment of the present invention, in which (a) is a defect perspective view and (b) is a perspective view of a main part.

FIG. 2 is a plan sectional view thereof.

FIG. 3 is a front sectional view thereof.

FIG. 4 is a flowchart for explaining the operation.

5 (a), (b), (c), (d), and (e) are explanatory views showing an example of a method of utilizing inspection data.

[Explanation of symbols]

1 ... Reticle (photomask), 2 ... Case, 3 ... Foreign matter, 10 ... Reticle management system (photomask management system), 11 ... Storage box, 12 ... Clean bench, 13
… Storage rack, 14… Transport robot, 15… Arm, 16…
Grip, 17 ... entrance / exit, 18 ... entry / exit receiving rack, 19
... Contact port, 20 ... Foreign matter inspection device (defect inspection device), 21
... clean bench, 22 ... optical inspection device, 23 ... table, 24 ... inspection light, 25 ... irradiation device, 26 ... scattered light,
27 ... Light receiver, 28 ... Controller of foreign matter inspection device, 2
9 ... Transport robot, 30 ... Arm, 31 ... Grip, 3
2 ... Entry / Exit Port, 33 ... Entry / Exit Rack, 34 ... Contact Port, 3
5 ... Delivery device, 36 ... Communication passage, 37 ... Delivery object detection device, 38 ... Projector, 39 ... Photoreceiver, 40 ... General controller.

Claims (3)

[Claims] 1. A storage cabinet for identifying a plurality of photomasks by an identification code attached to each photomask and storing each in a predetermined location, and a defect for inspecting each photomask for defects and outputting the inspection result. The storage device, the defect inspection device, and the delivery device are connected to a general controller and are integrally controlled by the inspection device and the delivery device for mutually passing the photomask between the storage device and the defect inspection device. A photomask management system characterized by being configured as follows. 2. The delivery device is configured to perform the delivery work of the photomask in a sealed communication passage that connects the inside of the storage and the machine frame of the defect inspection device. The photomask management system according to claim 1. 3. The overall controller stores each inspection result of the defect inspection device and its inspection time in association with an identification code of the photomask, and collates stored data relating to each photomask with each other based on the identification code. The photomask management system according to claim 1, wherein the photomask management system is configured to: