JP2007248596A - Opc inspection system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical proximity effect correction (OPC) inspection system which is good in facility efficiency. <P>SOLUTION: An OPC correction/verification server 1 is connected to a plurality of user terminals 2 through an FTP server 31 and a mail server 32 which are connected through a communication line 4. One of a plurality of parameters for OPC correction stored in a library 13, a lithography model, a recipe or rule for OPC verification is instructed by an OPC correction/verification execution instruction section 21 and read out to an OPC correction/verification control section 12, and when the start of execution is instructed, an OPC correction/verification execution section 11 executes OPC verification of an OPC-corrected layout pattern and stores an execution result in an execution result storage section 16. An execution monitor section 15 reports the end of the execution to an execution state display section 22. If an error occurs, the execution result is transferred to a verification result storage section 23 and displayed at an OPC verification result display section 24 while superposed on the pattern before OPC processing. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an OPC inspection system that inspects a layout pattern subjected to OPC (Optical Proximity Correction) processing.

  With the miniaturization of LSI, the optical proximity effect becomes more prominent in optical exposure of mask patterns. Therefore, when generating the drawing mask pattern, an OPC process for correcting the layout pattern in the design is performed in consideration of the optical proximity effect in advance.

  One of the OPC methods is model-based OPC. In model-based OPC, a lithography model based on lithography simulation is generated, and correction is performed using the lithography model so that an exposure image close to the original layout pattern is formed on the wafer.

  A file in which layout pattern data and various parameters for OPC are described is input to the OPC correction tool that performs such OPC processing. The OPC correction tool outputs the OPC processed layout pattern after the OPC processing is completed.

  OPC verification using an exposure simulation is performed on the OPC processed layout pattern. By this OPC verification, an OPC-processed layout pattern that is considered to have a deviation of an exposure image with respect to a desired pattern larger than a specified value is detected.

  The OPC verification tool that performs such OPC verification includes a recipe that describes what deviation should be detected, a rule that describes the allowable value of the deviation, various parameters used in OPC correction, and model-based OPC correction. The lithography model used is input. The OPC verification tool inspects the OPC-processed layout pattern according to the input rule, and outputs the coordinates or the like where a pattern causing an error in the manufacturing process occurs (file).

  For the layout pattern in which an error has occurred, the OPC correction parameters and the lithography model are corrected and the OPC process is performed again, the OPC verification recipe is corrected as necessary, and the OPC verification process is performed again. .

  Alternatively, the layout pattern for the error is corrected for the layout pattern in which an error has occurred, and OPC correction and verification are performed again.

  Such OPC correction and OPC verification processing is usually performed by an LSI designer. In view of this, a layout design support apparatus is provided to support execution of OPC correction and OPC verification by LSI designers (see, for example, Patent Document 1). The LSI design person repeatedly executes OPC correction and OPC verification until a desired correction result is obtained using such a layout design support apparatus.

  Conventionally, the layout design support apparatus as described above is often provided as a stand-alone EWS (Engineering Work Station), and each LSI designer in charge uses an EWS prepared for the OPC correction and the EWS correction. Verification of the OPC result was performed.

However, with the recent miniaturization of LSIs, the amount of computation required for OPC correction and verification of OPC results has become enormous, and expensive high-performance EWS is required to perform processing in a practical execution time. It is a burden on capital investment to prepare a high-performance EWS for each LSI designer.
JP 2000-260879 A (page 3-4, FIG. 1)

  Therefore, an object of the present invention is to provide an OPC inspection system with high equipment efficiency.

  According to one aspect of the present invention, an OPC correction / verification server, a plurality of user terminals, and a communication unit that connects the OPC correction / verification server and the plurality of user terminals via a communication line. An OPC inspection system, wherein the OPC correction / verification server executes OPC correction for an input layout pattern and performs OPC verification for an OPC processed layout pattern, and the OPC correction. OPC correction / verification control means for controlling execution of OPC correction and OPC verification in the verification execution means, parameters and lithography model for OPC correction given to the OPC correction / verification control means, and recipes and rules for OPC verification And an OPC correction in the OPC correction / verification executing means. And execution monitoring means for monitoring the execution status of the OPC verification, and execution result storage means for storing the execution results of the OPC correction and the OPC verification output from the OPC correction / verification means. Each of the OPC correction / verification control means designates an OPC correction parameter, a lithography model, or a recipe and rule for OPC verification to be read from the library via the communication means, and the OPC correction / verification The execution status of the OPC correction and the OPC verification transmitted from the execution monitoring means via the communication means and the OPC correction / verification execution instructing means for instructing the start of the execution of the OPC correction or the OPC verification in the verification execution means. The execution status display means for displaying and the execution result storage means are transmitted via the communication means. An OPC inspection system comprising: an OPC verification result storage unit that stores the OPC verification result; and an OPC verification result display unit that displays the OPC verification result stored in the OPC verification result storage unit. Provided.

  According to the present invention, by providing an OPC correction / verification server commonly used by users and a plurality of user terminals connected to the OPC correction / verification server through communication means, each user can use each of them. The operator terminal can instruct the OPC correction / verification server to execute OPC and OPC verification, receive the OPC verification result from the OPC correction / verification server, and confirm the OPC verification result. Accordingly, it is not necessary to prepare expensive and high-performance equipment for OPC correction / verification processing for each user, and equipment efficiency for inspection of an OPC processed layout pattern can be improved.

  Embodiments of the present invention will be described below with reference to the drawings.

  The OPC inspection system according to the embodiment of the present invention transfers data between the OPC correction / verification server 1, the plurality of user terminals 2, and the OPC correction / verification server 1 and the plurality of user terminals 2. An FTP server 31 and a mail server 32 that transmits an email from the OPC correction / verification server 1 to a plurality of user terminals 2, and the FTP server 31 and the mail server 32 connected to the OPC correction / verification server 1 are The communication lines 4 are connected to a plurality of user terminals 2.

  FIG. 1 is a block diagram illustrating only one of a plurality of user terminals 2 and illustrating an example of a basic configuration of an OPC inspection apparatus according to the present embodiment.

  The OPC correction / verification server 1 executes an OPC on the input layout pattern and an OPC correction / verification execution unit 11 for executing an OPC verification on the OPC processed layout pattern, and an OPC correction in the OPC correction / verification execution unit 11. And an OPC correction / verification execution control unit 12 for controlling the execution of OPC verification, a parameter and a lithography model for OPC correction given to the OPC correction / verification execution control unit 12, and a recipe and rule for OPC verification 13, an execution monitoring unit 14 that monitors the execution status of OPC correction and OPC verification in the OPC correction / verification OPC verification unit 11, and an execution result storage unit that stores the OPC verification result output from the OPC correction / verification execution unit 11 15 and the layout pattern for OPC processing are stored And a design data storing section 16 that.

  The user terminal 2 designates the OPC correction parameters and lithography model to be read from the library 13 and the recipe and rules for OPC verification to the OPC correction / verification execution control unit 12 via the FTP server 31. The OPC correction / verification execution instructing unit 21 instructing the start of execution of OPC correction and OPC verification in the OPC correction / verification executing unit 11 and the OPC correction transmitted from the execution monitoring unit 14 via the mail server 32. The execution status display unit 22 that displays the execution status of OPC correction and OPC verification in the verification execution unit 11, and the OPC correction / verification execution unit 11 transmitted from the execution result storage unit 15 via the FTP server 31. The OPC verification result storage unit 23 that stores the OPC verification result, and the OPC verification result stored in the OPC verification result storage unit 23 It includes an OPC verification result display unit 24 which displays superimposed on the PC pretreatment layout pattern, and a design data storing section 25 for storing the inputted pre-OPC layout pattern.

  The library 13 of the OPC correction / verification server 1 includes parameters and lithography models for OPC correction and recipes for OPC verification that are assumed to be used by users who perform OPC and OPC verification by the user terminal 2. Rules are stored.

  The registered contents of the library 13 are disclosed to the user, and the user selects an OPC correction parameter and a lithography model that he / she wants to use, and a recipe and rule for OPC verification.

  The execution monitoring unit 14 of the OPC correction / verification server 1 monitors the execution status of the OPC correction and the OPC verification in the OPC correction / verification execution unit 11, and when an abnormality occurs in the execution of the OPC correction or OPC verification, a warning message is displayed. Is sent to the user terminal 2 via the mail server 32. When the OPC verification is normally completed, an e-mail of an end message is transmitted to the user terminal 2 via the mail server 32. In this end message, an outline of the OPC verification result is also described.

  The user terminal 2 displays the received warning message and end message on the execution status display unit 22. Thereby, the user of the user terminal 2 can confirm the contents of the warning message and the end message.

  In the execution result storage unit 15 of the OPC correction / verification server 1, when an error is detected by executing the OPC verification in the OPC correction / verification execution unit 11, an error occurrence position marker indicating an error occurrence position, and an error The generated OPC processed pattern is stored. The data stored in the execution result storage unit 15 is transmitted to the user terminal 2 via the FTP server 31 and stored in the execution result storage unit 23 of the user terminal 2.

  In the user terminal 2, the error occurrence position marker stored in the execution result storage unit 23 is displayed on the OPC verification result display unit 24. At this time, the OPC verification result display unit 24 can read the pre-OPC processing layout pattern stored in the design data storage unit 25 and display the error occurrence position marker on the pre-OPC processing layout pattern. Further, the OPC verification result display unit 24 can also display the OPC processed pattern in which an error has been read out from the execution result storage unit 23 in addition to these.

  In the design data storage unit 16 of the OPC correction / verification server 1, the pre-OPC layout pattern stored in the design data storage unit 25 of the user terminal 2 is transferred and stored via the FTP server 31.

  FIG. 2 is an example of an execution instruction input screen used in the OPC correction / verification execution instruction unit 21 of the user terminal 2. On this execution instruction input screen, target data, target layer and target area are specified, and target conditions and exposure conditions are specified, so that one of the library data registered in the library 13 is selected. In addition, on the execution instruction input screen, the output destination of the OPC verification result for the FTP server 31 and the e-mail transmission destination for the mail server 32 are also specified.

  On the execution instruction input screen, the OPC correction / verification execution instructing unit 21 instructs the OPC correction / verification execution control unit 12 of the OPC correction / verification server 1 to start execution of OPC correction and OPC verification. .

  In this embodiment, it is assumed that there are two execution modes for execution of OPC correction and OPC verification. One is an OPC correction mode in which OPC correction and OPC verification are successively executed (OPC correction + verification), and the other is an OPC verification mode in which only OPC verification is executed independently.

  Here, the (OPC correction + verification) mode is used, for example, when the OPC correction is executed for the first time. The OPC verification mode has already been subjected to the OPC processing pattern, and the OPC verification recipe or rule is changed, and the OPC verification is performed again. This is used when executing. This mode is also selected on the execution instruction input screen shown in FIG.

  FIG. 3 is a flowchart showing an example of an inspection flow for the OPC processed pattern in the OPC inspection apparatus of the present embodiment.

  In starting the inspection for the OPC processed pattern, first, the data to be read from the library 13 is specified from the OPC correction / verification execution instruction unit 21 of the user terminal 2 to the OPC correction / verification execution control unit 12 of the OPC correction / verification server 1. (Step S01).

  The OPC correction / verification control unit 12 reads the designated OPC correction parameters and lithography model, and the recipe and rules for OPC verification from the library 13 and sends them to the OPC correction / verification execution unit 11.

  Subsequently, after specifying either the (OPC correction + verification) mode or the OPC verification mode, the OPC correction / verification execution instructing unit 21 instructs the OPC correction / verification control unit 12 to start execution ( Step S02). Upon receiving this instruction, the OPC verification control unit 12 determines whether the execution mode is the (OPC correction + verification) mode or the OPC verification mode, and instructs the OPC correction / verification execution unit 11 to (OPC correction). When in the (+ Verification) mode, the execution of OPC correction is instructed, and when in the OPC verification mode, the execution of OPC verification is instructed (step S03).

  When receiving an instruction for OPC correction, the OPC correction / verification execution unit 11 executes OPC correction for the layout pattern stored in the design data storage unit 16 (step S04). When the execution of the OPC correction is started, the execution monitoring unit 15 monitors the execution status of the OPC correction / verification execution unit 11 and checks whether the OPC correction has been normally completed (step S05).

  If an abnormality occurs during the OPC correction and the OPC correction / verification execution unit 11 ends abnormally (NO), the execution monitoring unit 15 displays the execution status of the user terminal 2 via the mail server 32. An abnormality warning is transmitted to the unit 22 to notify that the OPC correction has ended abnormally (step S06). FIG. 4A shows an example of an abnormal warning e-mail. The user who receives such an abnormal warning e-mail takes measures to eliminate the cause and re-executes the OPC correction.

  Returning to FIG. 3, when the OPC correction is normally completed in step S05 (YES), the execution result of the OPC correction is stored in the execution result storage unit 15 (step S07).

  When the execution of the OPC correction ends normally in this way, or when the execution of the OPC verification is instructed in step S03, the OPC correction / verification execution unit 11 is stored in the execution result storage unit 15. OPC verification is performed on the OPC processed layout pattern (step S08).

  When the execution of the OPC verification is started, the execution monitoring unit 14 monitors the execution status of the OPC correction / verification execution unit 11 and checks whether the OPC verification is normally completed (step S09).

  If an abnormality occurs during the OPC verification and the OPC correction / verification execution unit 11 ends abnormally (NO), the execution monitoring unit 14 displays the execution status of the user terminal 2 via the mail server 32. As in the case of OPC correction, an abnormal warning as shown in FIG. 4A is transmitted to the unit 22 to notify that the OPC verification has ended abnormally (step S06). The user who receives the abnormal warning e-mail takes measures to eliminate the cause and re-executes the OPC verification.

  Returning to FIG. 3, when the OPC verification ends normally in step S <b> 09 (YES) and the execution result of the OPC verification is stored in the execution result storage unit 15 (step S <b> 10), the execution monitoring unit 14 sends the mail server 32. Is sent to the execution status display unit 22 of the user terminal 2 to notify that the OPC verification has been completed normally (step S11). This end notification describes the outline of the OPC verification result.

  If the number of errors due to the OPC verification check is 0 as shown in FIG. 4B in this end notification (NO in step S12), the user does not need to check the OPC verification result. This work is finished as it is.

  On the other hand, as shown in FIG. 4C, when the number of errors is described in the end notification (YES in step S12), the user needs to confirm the OPC verification result. At this time, since the summary of the error is described in the notified mail, the user can know the summary of the type of error.

  Returning to FIG. 3, if there is an error in the OPC verification result in step S <b> 12 (YES), the user sends an FTP transfer of the OPC verification result to the OPC correction / verification server 1 in order to confirm the details. Request. In response to this request, the OPC correction / verification server 1 transfers the OPC verification result stored in the execution result storage unit 15 to the user terminal 2 via the FTP server 31 (step S13).

  The user terminal 2 stores the transferred OPC verification result in the OPC verification result storage unit 23 (step S14).

  The user displays the OPC verification result stored in the OPC verification result storage unit 23 on the display screen of the OPC verification result display unit 24 (step S15). Thereby, an error generated by the OPC process can be visually confirmed. At this time, the layout pattern before the OPC processing stored in the design data storage unit 25 is read out and displayed on the OPC verification result so as to easily know where the error has occurred in the design data. This makes it easier to take measures to eliminate errors.

  There are the following three methods for overlaying the OPC verification result on the layout pattern before the OPC processing. That is, the first is to superimpose only the error occurrence position marker, the second is to superimpose the error occurrence position marker and the OPC processed pattern in which the error has occurred, and the third is the error occurrence position marker and the OPC in which the error has occurred. There are three ways of superimposing only around the error occurrence position marker in the processed pattern. Examples of these three superposition methods are shown in FIGS.

  FIG. 5 is an example of a display screen of the OPC verification result display unit 24 when only the error occurrence position marker is displayed superimposed on the layout pattern before the OPC process.

  With such a display, the user can visually grasp where the error has occurred on the design data.

  FIG. 6 is an example of a display screen of the OPC verification result display unit 24 when the error occurrence position marker and the OPC processed pattern in which an error has occurred are superimposed and displayed on the layout pattern before the OPC processing.

  With such a display, the user can check what shape the OPC processed pattern in which an error has occurred has.

  FIG. 7 shows the display of the OPC verification result display unit 24 when only the error occurrence position marker and the vicinity of the error occurrence position marker of the OPC processed pattern in which an error has occurred are superimposed and displayed on the layout pattern before the OPC process. It is an example of a screen.

  In this case, the display data amount can be reduced by displaying the OPC processed pattern only around the error occurrence position marker.

  As described above, a series of operations from the execution of the OPC verification to the OPC processed pattern to the confirmation of the result is completed.

  According to such a present Example, since the OPC correction | amendment / verification server which a user uses in common, and the some user terminal connected to this OPC correction | amendment / verification server through a communication means, each user is provided. Each user terminal can instruct the OPC correction / verification server to execute OPC correction and OPC verification, receive the OPC verification result from the OPC correction / verification server, and confirm the OPC verification result. Accordingly, it is not necessary to prepare expensive and high-performance equipment for OPC correction / verification processing for each user, and equipment efficiency for inspection of an OPC processed layout pattern can be improved.

  Further, according to the present embodiment, a standardized library is provided in the OPC correction / verification server, so that each user creates parameters and lithography models for OPC correction, and recipes and rules for OPC verification. This is unnecessary, and the OPC verification for the OPC processed pattern can be executed efficiently.

  In addition, since the end of the OPC verification is notified by electronic mail, the user can immediately know the end of the OPC verification. Further, when the OPC verification is completed normally, an outline of the detected error can be known by the notification.

  In addition, since the execution result of the OPC verification can be displayed superimposed on the layout pattern before the OPC process, the user can easily grasp where the error has occurred in the design data.

  FIG. 8 is a block diagram illustrating an example of the configuration of the OPC correction / verification server in the OPC inspection apparatus according to the second embodiment of the present invention.

  The OPC correction / verification server 1A of the present embodiment is obtained by adding an administrator authentication unit 17 to the OPC correction / verification server 1 of the first embodiment shown in FIG. 8, blocks having the same functions as those shown in FIG. 1 are denoted by the same reference numerals as those in FIG. 1, and detailed description thereof is omitted here.

  The administrator authenticating unit 17 permits only the library administrator having the administrator ID issued in advance to register the OPC correction parameters and the lithography model and the recipe and rules for OPC verification in the library 13.

  Since the library 13 is commonly used by all users, it is important to keep the contents accurate. In addition, version management must be strictly performed when contents are updated. Therefore, the administrator authentication unit 17 manages access to the library 13 and ensures the reliability of the library 13.

  The library 13 is updated when, for example, a new manufacturing process is developed or a new manufacturing apparatus is introduced. In such a case, parameters and lithography models for OPC correction and recipes and rules for OPC verification tailored to the process and apparatus are created, and after sufficient verification, they are registered in the library 13 by the administrator. Is done. At that time, the administrator authentication unit 14 requests the administrator to input an administrator ID, and permits registration of new data in the library 13 only when the correct administrator ID is input.

  According to the present embodiment, since the library installed in the OPC correction / verification server is strictly managed, any user can execute the inspection of the OPC processed layout pattern, and the result is constant. Quality can be kept.

1 is a block diagram illustrating an example of a basic configuration of an OPC inspection apparatus according to Embodiment 1 of the present invention. The figure which shows the example of the operation screen of the execution instruction | indication part of the user terminal of the OPC inspection apparatus which concerns on Example 1 of this invention. The flowchart which shows the example of the processing flow in the OPC inspection apparatus which concerns on Example 1 of this invention. The figure which shows the example of the display screen of the OPC verification status display part of the user terminal of the OPC inspection apparatus which concerns on Example 1 of this invention. The figure which shows the example of the display screen of the OPC verification result display part of the user terminal of the OPC inspection apparatus which concerns on Example 1 of this invention. The figure which shows the example of the display screen of the OPC verification result display part of the user terminal of the OPC inspection apparatus which concerns on Example 1 of this invention. The figure which shows the example of the display screen of the OPC verification result display part of the user terminal of the OPC inspection apparatus which concerns on Example 1 of this invention. The block diagram which shows the example of a structure of the OPC correction | amendment / verification server of the OPC inspection apparatus which concerns on Example 2 of this invention.

Explanation of symbols

1, 1A OPC correction / verification server 11 OPC correction / verification execution unit 12 OPC correction / verification execution control unit 13 Library 14 execution monitoring unit 15 execution result storage unit 16 design data storage unit 17 administrator authentication unit 2 user terminal 21 OPC Correction / Verification Execution Instruction Unit 22 Execution Status Display Unit 23 OPC Verification Result Storage Unit 24 OPC Verification Result Display Unit 25 Design Data Storage Unit 31 FTP Server 32 Mail Server 4 Communication Line

Claims (5)

An OPC inspection system comprising: an OPC correction / verification server; a plurality of user terminals; and communication means for connecting the OPC correction / verification server and the plurality of user terminals via a communication line,
The OPC correction / verification server
OPC correction / verification executing means for executing OPC correction for an input layout pattern and executing OPC verification for an OPC processed layout pattern;
OPC correction / verification control means for controlling execution of OPC correction and OPC verification in the OPC correction / verification execution means;
A library storing parameters and lithography models for OPC correction to be given to the OPC correction / verification control means, and recipes and rules for OPC verification;
Execution monitoring means for monitoring the execution status of OPC correction and OPC verification in the OPC correction / verification execution means;
Execution result storage means for storing execution results of OPC correction and OPC verification output from the OPC correction / verification means;
Each of the plurality of user terminals is
Via the communication means, the OPC correction / verification control means designates an OPC correction parameter, a lithography model, or an OPC verification recipe and rule to be read from the library, and the OPC correction / verification execution means. OPC correction / verification execution instructing means for instructing start of execution of OPC correction or OPC verification in
Execution status display means for displaying the execution status of the OPC correction and OPC verification transmitted from the execution monitoring means via the communication means;
OPC verification result storage means for storing the OPC verification result transmitted from the execution result storage means via the communication means;
OPC verification result display means for displaying the OPC verification result stored in the OPC verification result storage means;
An OPC inspection system comprising:   The OPC verification result display means displays both the error occurrence position marker and the error occurrence pattern included in the OPC verification result or only the error occurrence position marker on the layout pattern before the OPC process. The OPC inspection system according to claim 1.   The execution monitoring unit transmits a warning message when an abnormality occurs in the execution of the OPC verification, and transmits an end message when the execution of the OPC verification is completed to the user terminal that has instructed the execution of the OPC verification. The OPC inspection system according to claim 1.   4. The OPC inspection system according to claim 3, wherein the execution monitoring unit describes an outline of the OPC verification result in the end message.   The OPC inspection system according to claim 1, wherein the OPC correction / verification server further includes an administrator authentication unit that permits only a library administrator to update the library.

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