JP2005174959A - Lithographic system, program and information recording medium, support device and exposure method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable distortion matching between an original process and a current process even in the case of many-kind small-quantity production or the like in which a lot is divided after intermediate processes. <P>SOLUTION: A host 160 controlling a plurality of projection aligners 110<SB>1</SB>to 110<SB>N</SB>controls even original process information containing an image distortion correction value used in the case of the exposure of the original process. An arithmetic unit 130 computes adaptive devices using the difference of an image distortion between the original process and the current process as an allowable value and the image-distortion correction value in response to an inquiry from the host containing at least a part of the original-process information, and answers the information of the result of the computation to the host. Accordingly, the distortion matching between the original process and the current process by the selected projection aligner is enabled by imparting the image-distortion correction value by selecting one adaptive device without depending upon the discriminating information of the lot by the host. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a lithography system, a program and information recording medium, a support apparatus, and an exposure method. More specifically, the present invention relates to a lithography system that centrally manages a plurality of projection exposure apparatuses with a host computer system, and to the host computer system. The present invention relates to a program for causing a computer to execute a predetermined process, an information recording medium on which the program is recorded, a support apparatus used in a lithography system, and an exposure method performed in a system including the support apparatus.

  Conventionally, in a lithography process for manufacturing a semiconductor element, a liquid crystal display element or the like, a resist or the like is applied to a pattern formed on a mask or a reticle (hereinafter, collectively referred to as “reticle”) via a projection optical system. Projection exposure apparatuses that transfer images onto a substrate such as a wafer or a glass plate (hereinafter referred to as “wafer” where appropriate) are used. In manufacturing such a semiconductor element or the like, it is common to perform overlay exposure in order to form different circuit patterns stacked on a wafer in several layers.

  In recent years, in order to increase productivity, a plurality of projection exposure apparatuses are prepared, and a lithography system in which these projection exposure apparatuses are centrally managed by a host computer has been constructed. In such a system, the circuit pattern of each layer (layer) on one wafer is transferred using a different projection exposure apparatus in order to increase productivity. The projection exposure apparatus needs to be scheduled. For example, when the projection exposure apparatus used for exposure in the original process layer on the wafer (hereinafter also simply referred to as “original process”) is operating, another projection exposure apparatus that is not currently operating is displayed. If it is scheduled to be used for exposure of a process layer (current layer: hereinafter also referred to as “current process”), the entire exposure process can be shortened.

  A problem in executing such scheduling is distortion (distortion) of the transferred image between the projection exposure apparatuses. In order to ensure the overlay accuracy of images between layers, it is important to match such distortion between the projection exposure apparatuses.

  In response to increasing demands for higher overlay accuracy due to higher integration of semiconductor elements, this type of distortion matching system between multiple projection exposure systems is used as a system for image distortion correction capability between units and over time. Recently, a lithography system aimed at reducing the shot shape error between layers due to a change as much as possible has been proposed (for example, see Patent Document 1 below).

  The lithography system described in Patent Document 1 is a projection exposure apparatus in which distortion of a transfer image is brought close to an ideal value as much as possible in each projection exposure apparatus and exposure of one preceding layer (reference layer: original process) is performed. Adjusting the projection optical system of the projection exposure apparatus that exposes the subsequent layer (current process) so that the same distortion as that of the transferred image occurs, and aligning the transferred image with the original process (reference layer) It is. In the lithography system described in Patent Document 1, the distortion of the transfer image (projected image) in the current process is matched with the transfer image in the original process in the following procedure.

a. A lot history for each lot name is collected in advance from each exposure apparatus and stored in the centralized information server. In the lot history, data such as the name of the apparatus used for the exposure in the process, the distortion correction value used in the exposure, and the date and time when the exposure was performed are recorded. On the other hand, for each of all the exposure apparatuses constituting the system, image distortion (distortion) at the time of exposure of the apparatus is periodically measured, and the measurement result is stored in the central information server.

b. When a certain process (current process) is performed on a wafer of a certain lot, the host computer has an exposed layer (for example, a lot number) and an exposed layer that should ensure overlay accuracy for overlay exposure ( The information such as a reference layer (original process) is designated, and an image distortion calculation apparatus is inquired about an apparatus suitable for performing the process of the current process.

c. The image distortion calculation apparatus obtains the distortion data of the projection image related to the exposure of the original process from the exposure history in the centralized information server based on the received lot information (lot identifier and reference layer, etc.), and performs various calculation processes. A candidate list of compatible devices is transmitted to the host computer.

d. The host computer selects an apparatus that can carry out the lithography process most efficiently from the received candidate list, and performs wafer exposure for overlay exposure on the machine controller (MC) of the selected exposure apparatus. The lot identifier is designated and an exposure execution instruction is issued.

e. The MC that has received the instruction to execute the exposure designates the identifier of the lot of the wafer to be subjected to the overlay exposure and the identifier of the exposure apparatus controlled by itself, and distorts the projection image when the wafer of the lot is exposed. The adjustment parameter value is inquired of the image distortion arithmetic unit and a response is obtained. The MC sends the adjustment parameter value obtained as a response to the exposure apparatus. In the exposure apparatus, the image formation characteristic correction apparatus is controlled in accordance with the adjustment parameter value to adjust the distortion of the projected image, and then overlay exposure is executed.

  However, in the lithography system described in Patent Document 1, a lot identifier (and lot history) such as a lot number is required, and if the lot identifier is changed, information on the original process cannot be obtained. Even when a lot name is used, the lot name cannot be changed on the way. For this reason, in high-mix low-volume production that divides a lot from an intermediate process (for example, when a lot of 25 wafers are divided one after another in the intermediate process to produce various products), A conventional lithography system such as the system described in Patent Document 1 cannot be used.

  Further, in a conventional lithography system such as the lithography system described in Patent Document 1, the adjustment parameter value of the distortion of the projected image is acquired as an answer to the inquiry by the MC inquiring to the image distortion arithmetic unit immediately before the exposure. It was. For this reason, if the image distortion calculation device is down, the process cannot be processed using the optimum adjustment parameter value, and it is difficult to produce a good product even if the product production is continued under such circumstances. For some reason, production was suspended.

JP 2000-36451 A

The present invention has been made under the circumstances described above. From the first viewpoint, a plurality of projection exposure apparatuses (110 _{1 to} 110 _N) including at least one projection exposure apparatus capable of adjusting the distortion of a projected image. And a host computer system (160) for managing the plurality of projection exposure apparatuses and managing original process information including an image distortion correction value used in the exposure of the original process; In response to an inquiry from the host computer system including at least a part, the difference in the projection image distortion at the exposure of the current process with respect to the distortion of the projection image at the exposure of the original process is an allowable value. An image distortion correction value to be used in at least one adapting apparatus of the projection exposure apparatus and a projection exposure apparatus capable of adjusting the distortion of the projected image of the adapting apparatus is calculated, and information on the calculation result is calculated by the host calculation. Image distortion computing device to answer system (130); a first lithography system comprising a.

  Here, the “original process” means one preceding layer (reference layer) to be superposed or a processing process of the reference layer, and the “current process” means that the superposition with respect to the reference layer is performed. It means a processing step of a subsequent layer or a subsequent layer. In this specification, the terms “original process” and “current process” are used in this sense.

  According to this, the host computer system that manages a plurality of projection exposure apparatuses also manages the original process information including the image distortion correction value used in the exposure of the original process. Then, in response to an inquiry from the host computer system including at least a part of the original process information, the image distortion calculation device causes the distortion of the projection image at the exposure of the current process to the distortion of the projection image at the exposure of the original process. An image distortion correction value to be used in an adapting apparatus in which the difference between them is an allowable value and a projection exposure apparatus capable of adjusting the distortion of the projected image of the adapting apparatus is calculated, and information on the calculation result is returned to the host computer system. To do. As a result, the host computer system obtains the information on the image distortion correction value to be used by the image distortion calculation apparatus from the image distortion calculation apparatus and the projection exposure apparatus that can adjust the distortion of the projected image, out of the apparatus, regardless of the lot identification information. Based on the information, if one of the adaptive devices is selected and the selected adaptive device is a projection exposure device capable of adjusting the distortion of the projection image, the image distortion corresponding to the projection exposure device is obtained. A correction value is given to the adaptation device. Thus, exposure is performed in a state where the distortion of the projection image is corrected in accordance with the original process based on the image distortion correction value given by the matching apparatus. Therefore, even in the case of multi-product small-quantity production such as lot division from the middle, it is possible to perform distortion matching between the original process and the current process.

  In this case, the host computer system makes the inquiry to the image distortion arithmetic apparatus prior to exposure in the current process, and the information acquired from the image distortion arithmetic apparatus as a reply to the inquiry Until the exposure is started, it can be stored in an apparatus other than the image distortion calculation apparatus.

According to a second aspect of the present invention, there are provided a plurality of projection exposure apparatuses (110 _{1 to} 110 _N ) including at least one projection exposure apparatus capable of adjusting distortion of a projection image; and the plurality of projection exposure apparatuses. A host computer system (160) for managing the identification information of the projection exposure apparatus that performed the exposure of the original process and the date and time of exposure; and specifying the identification information of the exposure apparatus and the date and time of exposure In response to the inquiry from the host computer system, the exposure history information including the name of the projection exposure apparatus, the date and time when the exposure was performed, and the distortion of the projection image at the time of exposure, and the image distortion data for each projection exposure apparatus At least one of the plurality of projection exposure apparatuses in which a difference between the distortion of the projection image at the exposure of the current process and the distortion of the projection image at the exposure of the current process is an allowable value. And an image distortion calculation device (130) that calculates an image distortion correction value to be used in a projection exposure apparatus capable of adjusting the distortion of the projected image among the compatible devices, and returns information of the calculation result to the host computer system; A second lithography system comprising:

  According to this, in response to an inquiry from the host computer system that specifies the identification information of the projection exposure apparatus that performed the exposure in the original process and the date and time when the exposure was performed, the image distortion calculation apparatus performs exposure history information (of the original process). (Including the name of the exposure apparatus used for the exposure, the distortion correction value of the projection image used, and the date and time when the exposure was performed), and the image distortion data for each projection exposure apparatus. An adaptive apparatus in which the difference in distortion of the projected image during exposure in the current process with respect to the distortion of the projected image is an allowable value, and an image distortion correction value to be used in a projection exposure apparatus capable of adjusting the distortion of the projected image of the adaptive apparatus And the information of the calculation result is returned to the host computer system. As described above, the image distortion calculation device identifies the information at the time of the original process exposure of the lot from the device name and the date and time without using the lot identification information such as the lot name, and projects the matching device and the matching device. An image distortion correction value to be used in the projection exposure apparatus capable of adjusting the image distortion is calculated, and the information is returned to the host computer system. When the host computer system selects one adapting apparatus from the adapting apparatuses based on the information, and the selected adapting apparatus is a projection exposure apparatus capable of adjusting the distortion of the projected image. The image distortion correction value corresponding to the projection exposure apparatus is given to the adapting apparatus. Thus, exposure is performed in a state where the distortion of the projection image is corrected in accordance with the original process based on the image distortion correction value given by the matching apparatus. Therefore, even in the case of multi-product small-quantity production such as lot division from the middle, it is possible to perform distortion matching between the original process and the current process.

According to a third aspect of the present invention, there are provided a plurality of projection exposure apparatuses (110 _{1 to} 110 _N ) including at least one projection exposure apparatus capable of adjusting distortion of a projection image; and the plurality of projection exposure apparatuses. In response to an inquiry from the host computer system, the difference between the distortion of the projection image at the exposure of the current process and the distortion of the projection image at the exposure of the current process becomes an allowable value in response to an inquiry from the host computer system. Calculating an image distortion correction value to be used in at least one of the plurality of projection exposure apparatuses, and a projection exposure apparatus capable of adjusting the distortion of the projected image among the adaptation apparatuses, An image distortion calculation device (130) for replying information to the host computer system, and the host computer system makes the inquiry to the image distortion calculation device prior to exposure in the current process. And the information acquired from the image distortion calculation device as an answer to the inquiry is stored in a device other than the image distortion calculation device until exposure in the current process is started. Lithographic system.

  According to this, the host computer system makes an inquiry to the image distortion calculation device prior to the exposure in the current process, and information acquired from the image distortion calculation device as an answer to the inquiry (the matching device and the matching device) Among them, information on the calculation result of the image distortion correction value to be used in the projection exposure apparatus capable of adjusting the distortion of the projected image) is stored in an apparatus other than the image distortion calculation apparatus until the exposure in the current process is started. Therefore, even if the image distortion calculation device is down after the acquisition of the inquiry and before the exposure of the current process is performed, the host computer system uses the matching device stored in the device other than the image distortion calculation device and the matching device. Using the information of the calculation result of the image distortion correction value to be used in the projection exposure apparatus capable of adjusting the distortion of the projection image among the apparatuses, one of the adaptation apparatuses is selected, and the selected adaptation apparatus uses the distortion of the projection image. If the projection exposure apparatus is capable of adjusting the image, the image distortion correction value to be used in the projection exposure apparatus is given, and the adaptation apparatus processes the process using the image distortion correction value optimum for the current process. It becomes possible.

  In this case, the host computer system can store the inquiry and the information acquired as an answer to the inquiry while exposure is being performed by any of the projection exposure apparatuses.

  In the third lithography system of the present invention, the host computer system can make the inquiry immediately after the exposure of the process immediately before the current process is completed.

  In the first to third lithography systems of the present invention, the information on the answer from the image distortion calculation device includes a list of compatible devices sequentially arranged from a projection exposure apparatus having a small difference in distortion of the projection image. can do.

  From the fourth viewpoint, the present invention manages a plurality of projection exposure apparatuses including at least one projection exposure apparatus capable of adjusting the distortion of the projection image, and also uses the image distortion used in the exposure of the original process. A program for causing a computer connected to a host computer system that manages original process information including a correction value to execute predetermined processing, in response to an inquiry from the host computer system that includes at least part of the original process information, At least one of the plurality of projection exposure apparatuses, wherein a difference between the distortion of the projection image in the exposure of the current process with respect to the distortion of the projection image in the exposure of the original process is an allowable value; A procedure for calculating an image distortion correction value to be used in a projection exposure apparatus capable of adjusting the distortion of the projected image in the compatible apparatus; and a method of replying the calculation result information to the host computer system When; it is the first program to be executed by the computer.

  From the fifth viewpoint, the present invention manages a plurality of projection exposure apparatuses including at least one projection exposure apparatus capable of adjusting the distortion of the projection image, and identifies the projection exposure apparatus that has performed the exposure in the original process. A program for causing a computer connected to a host computer system for managing information and date and time of exposure to execute predetermined processing, wherein the host specifies identification information of the projection exposure apparatus and date and time of exposure In response to an inquiry from the computer system, using the exposure history information including information on the projection exposure apparatus name, the date and time when the exposure was performed, and the distortion of the projection image at the time of exposure, and the image distortion data for each projection exposure apparatus, At least one of the plurality of projection exposure apparatuses in which a difference in distortion of the projection image at the exposure of the current process with respect to the distortion of the projection image at the exposure of the original process is an allowable value. A procedure for calculating an image distortion correction value to be used in a projection exposure apparatus capable of adjusting distortion of a projection image among the combination apparatus and the adapting apparatus; and a procedure for returning information of the calculation result to the host computer system; A second program to be executed by the computer.

  The first and second programs of the present invention can be recorded on a computer-readable information recording medium. The first and second programs recorded on the information recording medium are installed in the computer, and the main program is recorded. By loading into the memory, the computer can execute the first and second programs of the present invention. Therefore, from the sixth point of view, the present invention can be said to be an information recording medium that can be read by a computer in which the first or second program of the present invention is recorded.

  From a seventh aspect, the present invention manages a plurality of projection exposure apparatuses including at least one projection exposure apparatus capable of adjusting distortion of a projected image, and controls the plurality of projection exposure apparatuses. A lithography system support apparatus connected via a communication line to a host computer system that manages original process information including an image distortion correction value used at the time of exposure, and at least a part of the original process information In response to an inquiry from the host computer system including the above, the plurality of projection exposure apparatuses in which a difference in distortion of the projection image at the exposure of the current process with respect to the distortion of the projection image at the exposure of the original process becomes an allowable value An image distortion correction value to be used in at least one of the adaptive apparatuses and a projection exposure apparatus capable of adjusting the distortion of the projected image among the adaptive apparatuses is calculated, and information on the calculation result is calculated as the above-described information. A first support device of a lithography system comprising a computing device to answer preparative computer system.

  According to this, the host computer system obtains the information on the image distortion correction value to be used in the projection apparatus that can adjust the distortion of the projected image from the matching apparatus and the matching apparatus from the calculation apparatus, regardless of the lot identification information. Based on the information, if one of the adaptive devices is selected and the selected adaptive device is a projection exposure device capable of adjusting the distortion of the projection image, the image distortion corresponding to the projection exposure device is obtained. A correction value is given to the adaptation device. Thus, exposure is performed in a state where the distortion of the projection image is corrected in accordance with the original process based on the image distortion correction value given by the matching apparatus. Therefore, even in the case of multi-product small-quantity production such as lot division from the middle, it is possible to perform distortion matching between the original process and the current process.

  From an eighth aspect, the present invention manages a plurality of projection exposure apparatuses including at least one projection exposure apparatus capable of adjusting distortion of a projected image, and controls the plurality of projection exposure apparatuses. Identification information of a projection exposure apparatus that has performed exposure and a support apparatus of a lithography system that is connected via a communication line to a host computer system that manages the date and time when the exposure was performed, the identification information of the projection exposure apparatus In response to an inquiry from the host computer system designating the date and time when the exposure was performed, the exposure history information including the projection exposure apparatus name, the date and time when the exposure was performed and the distortion of the projected image at the time of exposure, and the projection Using the image distortion data for each exposure apparatus, the difference between the projection image distortion at the exposure of the current process and the distortion of the projection image at the exposure of the original process is an allowable value. An image distortion correction value to be used in at least one adapting apparatus of the projection exposure apparatus and a projection exposure apparatus capable of adjusting the distortion of the projected image of the adapting apparatus is calculated, and information of the calculation result is used as the host computer. It is a 2nd assistance apparatus of a lithography system provided with the arithmetic unit which answers a system.

  According to this, information at the time of the original process exposure of the lot is specified from the device name and date and time without using the lot identification information such as the lot name, and the matching device and the projection image of the matching device. The image distortion correction value to be used in the projection exposure apparatus capable of adjusting the distortion is calculated, and the information is returned to the host computer system. When the host computer system selects one adapting apparatus from the adapting apparatuses based on the information, and the selected adapting apparatus is a projection exposure apparatus capable of adjusting the distortion of the projected image. The image distortion correction value corresponding to the projection exposure apparatus is given to the adapting apparatus. Thus, exposure is performed in a state where the distortion of the projection image is corrected in accordance with the original process based on the image distortion correction value given by the matching apparatus. Therefore, even in the case of multi-product small-quantity production such as lot division from the middle, it is possible to perform distortion matching between the original process and the current process.

  According to a ninth aspect of the present invention, there are provided a plurality of projection exposure apparatuses including at least one projection exposure apparatus capable of adjusting distortion of a projected image, and a host computer system that manages the plurality of projection exposure apparatuses. Lithography system support devices connected via communication lines, respectively, and in response to an inquiry from the host computer system made prior to the exposure of the current process, the current distortion to the projected image during the exposure of the original process At least one adapting apparatus of the plurality of projection exposure apparatuses, and a projection capable of adjusting the distortion of the projected image among the adapting apparatuses, wherein a difference in distortion of the projected image at the time of exposure in the process is an allowable value. In order to calculate an image distortion correction value to be used in the exposure apparatus and store the information of the calculation result in an apparatus other than the own apparatus until exposure of the current process is started, the host computer A third support device of a lithography system comprising a computing device to answer the stem.

  According to this, information obtained from the computing device as an answer to the inquiry (the calculation result of the image distortion correction value to be used in the adapting device and the projection exposure apparatus capable of adjusting the distortion of the projected image of the adapting device) Information) is stored in an apparatus other than the support apparatus until exposure in the current process is started. Therefore, even if the support device goes down after the response to the inquiry is acquired and before the exposure of the current process is performed, the host computer system projects the matching device stored in the device other than the support device and the matching device among the matching devices. Using the information of the calculation result of the image distortion correction value to be used in the projection exposure apparatus capable of adjusting the image distortion, one of the matching apparatuses is selected, and the selected matching apparatus can adjust the distortion of the projection image. In the case of a projection exposure apparatus, by giving an image distortion correction value to be used in the projection exposure apparatus, it is possible to process the process using the image distortion correction value optimum for the current process by the adapting apparatus. Become.

  From a tenth aspect, the present invention manages a plurality of projection exposure apparatuses including at least one projection exposure apparatus capable of adjusting distortion of a projected image, and controls the plurality of projection exposure apparatuses, A host computer system for managing original process information including an image distortion correction value used at the time of exposure; and a plurality of projection exposure apparatuses and a support apparatus connected to the host computer system via a communication line. An exposure method used in a system comprising: a current process for distortion of a projected image during exposure of an original process in response to an inquiry from the host computer system including at least part of the original process information At least one adaptable apparatus capable of adjusting the distortion of the projected image of the plurality of projection exposure apparatuses, wherein the difference in distortion of the projected image at the time of exposure is an allowable value. Calculating an image distortion correction value to be used in the apparatus, and returning information of the calculation result to the host computer system; and the host computer system performs exposure of the current process from the adapting apparatus according to the response. Selecting a projection exposure apparatus to be executed, and giving an exposure instruction including designation of the image distortion correction value to the selected projection exposure apparatus; and the selected projection exposure apparatus is based on the image distortion correction value. A step of performing exposure in the current step in a state in which the distortion of the projected image of the apparatus is adjusted.

  According to this, exposure is performed in a state where the distortion of the projection image is corrected in accordance with the original process based on the given image distortion correction value by the selected exposure apparatus. Therefore, even in the case of multi-product small-quantity production such as lot division from the middle, it is possible to perform distortion matching between the original process and the current process.

  According to an eleventh aspect of the present invention, a plurality of projection exposure apparatuses including at least one projection exposure apparatus capable of adjusting distortion of a projected image, and managing the plurality of projection exposure apparatuses, A host computer system that manages the identification information of the projection exposure apparatus that has performed the exposure and the date and time when the exposure was performed; and a support apparatus that is connected to each of the plurality of projection exposure apparatuses and the host computer system via communication lines In response to an inquiry from the host computer system that specifies the identification information of the projection exposure apparatus and the date and time when the exposure was performed, the support apparatus uses the projection exposure apparatus name, the exposure method The exposure of the original process using the exposure history information including information on the date and time when the exposure was performed and the distortion of the projection image at the time of exposure, and the image distortion data for each projection exposure apparatus At least one adaptable device capable of adjusting the distortion of the projected image among the plurality of projection exposure apparatuses, wherein a difference in the distortion of the projected image at the time of exposure in the current process with respect to the distortion of the projected image is an allowable value A step of calculating an image distortion correction value to be used in the adapting device and returning information of the calculation result to the host computer system; the host computer system responding to the answer from the adapting device to the current step A step of selecting a projection exposure apparatus that performs the exposure, and giving an exposure instruction including designation of the image distortion correction value to the selected projection exposure apparatus; and the selected projection exposure apparatus performs the image distortion correction. And a step of performing exposure in the current step in a state in which the distortion of the projection image of the device itself is adjusted based on the value.

  According to this, exposure is performed by the selected projection exposure apparatus in a state where the distortion of the projection image is corrected according to the original process based on the given image distortion correction value. Therefore, even in the case of multi-product small-quantity production such as lot division from the middle, it is possible to perform distortion matching between the original process and the current process.

  According to a twelfth aspect of the present invention, a plurality of projection exposure apparatuses including at least one projection exposure apparatus capable of adjusting the distortion of a projected image, a host computer system that manages the plurality of projection exposure apparatuses, An exposure method used in a system including the plurality of projection exposure apparatuses and a support apparatus connected to the host computer system via a communication line, which is performed before exposure of the current process from the host computer system. In response to the received inquiry, the support apparatus determines whether a difference in the distortion of the projection image at the exposure of the current process with respect to the distortion of the projection image at the exposure of the original process is an allowable value. At least one adapting device capable of adjusting the distortion of the projected image, an image distortion correction value to be used by the adapting device, and information of the calculation result as the host computer system A step of replying; a step of storing information of the calculation result in a device other than the support device after the host computer system receives the information of the calculation result from the support device until exposure of the current process is started; When the host computer system starts exposure in the current process, the host computer system selects a projection exposure apparatus that performs exposure in the current process from the matching apparatuses included in the information of the calculation result, and the selected projection exposure apparatus An exposure instruction including designation of the image distortion correction value; and the selected projection exposure apparatus adjusts the distortion of the projection image of the apparatus itself based on the image distortion correction value. A third exposure method comprising: performing exposure of the process.

  According to this, even if the support device goes down after the response to the inquiry is acquired and before the exposure of the current process is performed, the host computer system uses the adapting device stored in a device other than the support device and the adapting device. Is used to select one of the adapting devices using the information of the calculation result of the image distortion correction value to be used in the projection exposure apparatus capable of adjusting the distortion of the projected image, and the selected adapting device determines the distortion of the projected image. In the case of an adjustable projection exposure apparatus, the image distortion correction value to be used in the projection exposure apparatus is given to process the process using the image distortion correction value optimum for the current process by the adapting apparatus. Is possible.

  From another viewpoint, the present invention is a device manufacturing method including a lithography process in which any one of the first to third exposure methods of the present invention is performed.

<< First Embodiment >>
A first embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 schematically shows the configuration of a lithography system 100 according to the first embodiment of the present invention. The lithography system 100 includes N projection exposure apparatuses 110 _{1 to} 110 _N , an SDM server (Super Distortion Matching Server) 130 as an image distortion calculation apparatus, a storage device 140, a terminal server 150, a host computer system 160, and the like. Yes.

Among these, each projection exposure apparatus 110 _i (i = 1, 2,..., N), the SDM server 130 and the terminal server 150 are connected to a local area network (LAN) 170. In addition, the storage device 140 is connected to the SDM server 130 via a communication path 180 such as a skazy (SCSI). The host computer system 160 is connected to the LAN 170 via the terminal server 150. That is, on the hardware configuration, each projection exposure apparatus 110 _i (i = 1, 2,..., N), SDM server 130 (and storage device 140), terminal server 150, and host computer system 160 are mutually connected. A communication path is secured.

Each of the projection exposure apparatuses 110 _{1 to} 110 _N may be a step-and-repeat projection exposure apparatus, a so-called stepper (hereinafter referred to as “static exposure apparatus”), or a step-and-repeat system. It may be a scanning projection exposure apparatus, that is, a scanning stepper (hereinafter referred to as “scanning exposure apparatus”). In the following description, for convenience of explanation, it is assumed that N is an even number, and all of the N projection exposure apparatuses 110 _{1 to} 110 _N have the ability to adjust the distortion of the projected image, and the odd-numbered projection exposure. 110 _1, 110 _3, ..., a 110 _N-1 is a scanning type exposure apparatus, and the even-numbered projection exposure apparatus 110 _2, 110 _4, ..., is assumed 110 _N is a static exposure apparatus .

Figure 2 shows a schematic arrangement of a projection exposure apparatus 110 ₁ is one of a scanning type exposure apparatus in FIG 1 is shown. As shown in FIG. 2, the projection exposure apparatus 110 ₁ includes an illumination system IOP, a reticle stage RST that holds a reticle R as a mask, a projection optical system PL, a wafer stage WST on which a wafer W as an object is mounted, and the like. I have.

The illumination system IOP includes a light source and an illumination uniformizing optical system including an optical integrator (such as a fly-eye lens, an internal reflection type integrator (lot integrator), or a diffractive optical element), a relay lens, a variable ND filter, and a reticle blind ( A field stop called a masking blade), and an illumination optical system including a relay optical system including a condenser lens (both not shown). A configuration of an illumination system similar to that of the present embodiment is disclosed in, for example, JP-A-6-349701. In this illumination system IOP, a slit-shaped (long and narrow rectangular shape extending in the X-axis direction) illumination region defined by a reticle blind on a reticle R on which a circuit pattern or the like is drawn is illuminated with substantially uniform illuminance by illumination light IL. . As the illumination light IL, for example, far ultraviolet light such as KrF excimer laser light (wavelength 248 nm), vacuum ultraviolet light such as ArF excimer laser light (wavelength 193 nm), F ₂ laser light (wavelength 157 nm), or the like is used. Note that as the illumination light IL, an ultraviolet bright line (g-line, i-line, etc.) from an ultra-high pressure mercury lamp may be used.

  On reticle stage RST, reticle R is fixed, for example, by vacuum suction. Here, the reticle stage RST is moved in the XY plane perpendicular to the optical axis of the illumination optical system (coincided with the optical axis AX of the projection optical system PL described later) by a reticle stage drive unit (not shown) composed of a linear motor or the like. It can be driven in the axial direction, the Y-axis direction, and the θz direction (rotation direction around the Z-axis) and can be driven at a scanning speed specified in a predetermined scanning direction (here, the Y-axis direction). Yes. The position of the reticle stage RST in the stage moving surface is always detected by a reticle laser interferometer (hereinafter referred to as “reticle interferometer”) 16 through the moving mirror 15 with a resolution of about 0.5 to 1 nm, for example. Position information of reticle stage RST from reticle interferometer 16 is sent to main controller 50, which controls reticle stage RST via the reticle stage drive unit based on the position information of reticle stage RST. .

The projection optical system PL is disposed below the reticle stage RST in FIG. 2, and the direction of the optical axis AX is the Z-axis direction. As the projection optical system PL, here, for example, double-sided telecentric composed of a plurality of lens elements 27 and 29 and a plurality of other lens elements arranged at predetermined intervals along the optical axis AX in the lens barrel 32. A refraction system is used. The projection magnification of the projection optical system PL is, for example, 1/5 (or 1/4), and a reduced image of the circuit pattern is projected onto an exposure area conjugate with the illumination area described above with respect to the projection optical system PL. For this reason, when the illumination region on the reticle R is illuminated by the illumination light IL from the illumination system IOP, the illumination light IL that has passed through the reticle R causes the circuit of the reticle R in the illumination region to pass through the projection optical system PL. A reduced image (partial inverted image) of the pattern is formed on the wafer W having a resist (photosensitive agent) coated on the surface. This projection exposure apparatus 110 ₁ is provided with an image formation characteristic correction apparatus that corrects distortion (including magnification) of a projection image by the projection optical system PL.

  Next, the imaging characteristic correction device will be described. This imaging characteristic correction device corrects changes in imaging characteristics of the projection optical system PL itself due to changes in atmospheric pressure, absorption of illumination light, and the like, and shot regions (for example, the previous layer) of a preceding specific layer on the wafer W ( It functions to distort the projected image of the pattern of the reticle R in accordance with the distortion of the pattern image transferred to the partition area. As the imaging characteristics of the projection optical system PL, there are projection magnification, focal position, field curvature, distortion, astigmatism, coma aberration, spherical aberration, etc., and mechanisms for correcting them are conceivable. The imaging characteristics other than the position can be corrected, for example, by moving the lens element of the projection optical system PL. In the following description, the imaging characteristics correction device mainly relates to distortion (including magnification) of the projection image. Only correction will be performed.

  In FIG. 2, the lens element 27 that is closest to the reticle R (closest to the object plane) and that constitutes the projection optical system PL is held by an annular holding member 28. The holding member 28 is provided with a plurality of extendable (here, three) drive elements, for example, piezo elements 11a, 11b, and 11c (however, the drive element 11c on the back side in FIG. 2 is not shown). The lens element 29 is supported on the upper surface of an annular holding member that holds the lens element 29. The drive voltage applied to the drive elements 11a, 11b, and 11c is independently controlled by the imaging characteristic control unit 12, whereby the lens element 27 is arbitrarily inclined and optical axis with respect to the plane orthogonal to the optical axis AX. It is configured to be movable in the AX direction.

  Similarly to the lens element 27, the lens element 29 following the lens element 27 is arbitrarily tilted and driven in the direction of the optical axis AX with respect to a plane orthogonal to the optical axis AX by a plurality of drive elements. The remaining lens elements are fixed to the lens barrel 32 of the projection optical system PL.

  In the present embodiment, only the lens elements 27 and 29 are movable independently in the lens barrel 32 of the projection optical system PL, but three or more lens elements may be movable, or at least two lenses. The lens group holding the elements integrally may be movable.

  The positions of the lens elements 27 and 29 are strictly measured by a position sensor (not shown), and the drive amount of each drive element is controlled by the imaging characteristic control unit 12 in accordance with an instruction from the main controller 50 based on the measurement result. As a result, the positions of the lens elements 27 and 29 are maintained at the target positions.

In the projection exposure apparatus 110 ₁ , the holding member 28 of the lens element 27, the holding member of the lens element 29, a plurality of driving elements (11 a, 11 b, 11 c, etc.), and an imaging characteristic control unit that controls the driving voltage for each driving element. 12 constitutes an imaging characteristic correction device (having a magnification adjustment function). Note that the optical axis AX of the projection optical system PL indicates the common optical axis of the lens elements fixed to the lens barrel 32.

  The imaging characteristic control unit 12 not only controls driving of the lens element via the driving element described above but also controls the light source to shift the center wavelength of the illumination light IL, thereby forming the imaging characteristics of the projection optical system ( (Distortion of the projected image) is adjusted.

  Wafer stage WST is arranged below projection optical system PL in FIG. 2, and is levitated and supported on a base (not shown) via a predetermined clearance by a static gas bearing (not shown) provided on the bottom surface of linearly linear linear stage. A wafer stage drive unit (not shown) including an actuator such as a motor is driven freely in the X-axis direction and the Y-axis direction, and also in the Z-axis direction, θz direction, θx direction (rotation direction around the X axis), and θy direction. It is finely driven in the direction of rotation around the Y axis.

  A substantially circular wafer holder 9 is provided on wafer stage WST, and wafer W is vacuum-sucked by this wafer holder 9 and flattened and held. The wafer holder is made of a low thermal expansion material in order to suppress expansion deformation due to heat accumulation during exposure of the wafer W.

  The position of wafer stage WST in the XY plane is always detected by a wafer laser interferometer (hereinafter referred to as “wafer interferometer”) 18 through moving mirror 17 with a resolution of, for example, about 0.5 to 1 nm. Position information (or speed information) of wafer stage WST is sent to main controller 50, which controls wafer stage WST via the wafer stage drive unit based on the position information (or speed information). To do.

  In practice, the moving mirror is provided with an X moving mirror having a reflecting surface orthogonal to the X axis and a Y moving mirror having a reflecting surface orthogonal to the Y axis. An X laser interferometer for measuring the axial position and a Y laser interferometer for measuring the Y axial position are provided. In FIG. 2, these are shown as a movable mirror 17 and a wafer interferometer 18 as representatives. Yes. For example, the end surface of wafer stage WST may be mirror-finished to form a reflecting surface (corresponding to the reflecting surface of movable mirror 17). The X laser interferometer and the Y laser interferometer are multi-axis interferometers having a plurality of measurement axes, and in addition to the X and Y positions of the wafer stage WST, rotation (yawing (θz rotation that is rotation around the Z axis)) , Pitching (θx rotation that is rotation around the X axis), and rolling (θy rotation that is rotation around the Y axis)) can also be measured. Therefore, in the following description, it is assumed that the position of wafer stage WST in the X, Y, θz, θy, and θx directions of five degrees of freedom is measured by wafer laser interferometer 18. Further, the multi-axis interferometer irradiates the laser beam on the reflecting surface installed on the gantry (not shown) on which the projection optical system PL is placed via the reflecting surface installed on the wafer stage WST with an inclination of 45 °. The relative position information regarding the optical axis direction (Z-axis direction) of the projection optical system PL may be detected.

  Further, a reference mark plate FM whose surface is set at substantially the same height as the surface of wafer W is fixed to the upper surface of wafer stage WST. On the surface of the reference mark plate FM, a reference mark for baseline measurement of an alignment sensor, which will be described later, a reference mark for reticle alignment, and the like are formed in a predetermined positional relationship.

  On the side surface of the projection optical system PL, an off-axis type alignment detection system for detecting the position of an alignment mark (wafer mark) attached to each shot area on the wafer W, for example, an image processing type imaging type An alignment sensor 8 is provided. The alignment sensor 8 irradiates the target mark with a broadband detection light beam that does not sensitize the resist on the wafer W, and forms an image of the target mark formed on the light receiving surface by reflected light from the target mark and an index image (not shown). Is an image processing type FIA (Field Image Alignment) type sensor that outputs an image pickup signal using an image pickup device (CCD or the like). In addition to the FIA system, a target mark is irradiated with coherent detection light, and scattered light or diffracted light generated from the target mark is detected, or two diffracted lights (for example, of the same order) generated from the target mark. Of course, it is possible to use an alignment sensor that detects the interference by interfering with each other alone or in combination. The detection result of the alignment sensor 8 is output to the main controller 50 through an alignment signal processing system (not shown).

The projection exposure apparatus 110 _{1 also} includes an irradiation system 13 for supplying an imaging light beam for forming a plurality of slit images toward the best imaging surface of the projection optical system PL from an oblique direction with respect to the optical axis AX direction. An oblique incidence type multipoint focal point detection system is provided which includes a light receiving system 14 for receiving each reflected light beam of the imaging light beam on the surface of the wafer W through a slit. As this multipoint focal position detection system (13, 14), for example, one having the same configuration as that disclosed in Japanese Patent Laid-Open No. 6-283403 is used. Wafer position information detected by the multipoint focal position detection system (13, 14) is supplied to the main controller 50. Main controller 50 drives wafer stage WST in the Z-axis direction and the tilt direction via the wafer stage drive unit based on the wafer position information, and performs focus / leveling control of wafer W.

The main controller 50, for example, a microcomputer, generally controls each component of the projection exposure apparatus 110 ₁ as described above. Further, in the present embodiment, the main controller 50, coater developer (not shown) which are parallel in the projection exposure apparatus 110 ₁ (hereinafter, referred to as "C / D") is also controlled. The main control device 50 is connected to the LAN 170.

Next, the operation of the exposure process in the projection exposure apparatus 110 ₁ configured as described above, with reference to FIG. 2 will be briefly described.

  In main controller 50, while monitoring position information from interferometers 16 and 18, wafer stage WST is moved to a scan start position (acceleration start position) for exposure of the first shot region on wafer W, and The reticle stage RST is moved to the scanning start position (acceleration start position), and scanning exposure of the first shot area is performed.

  In other words, main controller 50 starts relative scanning of reticle stage RST and wafer stage WST in the opposite directions in the Y-axis direction. When both stages RST and WST reach their respective target scanning speeds, reticle R is exposed by exposure light IL. The pattern area starts to be illuminated, and scanning exposure is started.

  In main controller 50, particularly during the above-described scanning exposure, movement speed Vr of reticle stage RST in the Y-axis direction and movement speed Vw of wafer stage WST in the Y-axis direction have a speed ratio corresponding to the projection magnification of projection optical system PL. The reticle stage RST and wafer stage WST are synchronously controlled so as to be maintained.

  Then, different areas of the pattern area of the reticle R are sequentially illuminated with the exposure light IL, and the illumination of the entire pattern area is completed, thereby completing the scanning exposure of the first shot area on the wafer W. Thereby, the circuit pattern of the reticle R is reduced and transferred to the first shot area on the wafer W through the projection optical system PL.

  Thus, when the scanning exposure (transfer of the circuit pattern of the reticle R by the scanning exposure method) to the first shot area on the wafer W is completed, the wafer stage WST is used to expose the second shot area on the wafer W. A stepping operation between shots to be moved to the scanning start position is performed. Then, the scanning exposure for the second shot area is performed in the same manner as described above. Thereafter, the same operation is performed after the third shot area.

  In this way, the stepping operation between shots and the scanning exposure operation for the shot area are repeated, and the pattern of the reticle R is transferred to all the shot areas on the wafer W by the step-and-scan method.

Projection exposure apparatuses 110 ₃ , 110 ₅ ,..., 110 _N−1 , which are other scanning exposure apparatuses, are configured in the same manner as the projection exposure apparatus 110 ₁ .

Further, the projection exposure apparatuses 110 ₂ , 110 ₄ ,..., 110 _N composed of a static exposure apparatus are basically configured in the same manner as the projection exposure apparatus 110 _{1 of} FIG. However, these projection exposure apparatuses 110 ₂ , 110 ₄ ,..., 110 _N are configured such that each reticle stage can only be slightly driven in the X, Y, and θz (rotation about the Z axis) directions in the XY plane. 2 and the irradiation area of the illumination light IL within the circular field of view of the projection optical system PL (corresponding to the above-described illumination area and exposure area) is larger than that of the scanning exposure apparatus of FIG. The difference is that it has the same size as the scanning exposure range. In these projection exposure apparatuses, exposure is performed with both the wafer stage and the reticle stage stationary.

Returning to FIG. 1, the above-described main controller 50 constituting each projection exposure apparatus 110 _i communicates with the host computer system 160 via the LAN 170 and the terminal server 150, and instructs from the host computer system 160. Various control operations are executed according to the above.

Returning to FIG. 1, the SDM server 130 is a support device for a lithography system configured by a medium-sized computer system (for example, a minicomputer system or an engineering workstation system) having excellent computing power. The SDM server 130 communicates with the host computer system 160 via the LAN 170 and the terminal server 150 in addition to the communication with the projection exposure apparatuses 110 _{1 to} 110 _N via the LAN 170.

In addition, the SDM server 130 reads / writes data from / to the storage device 140 as necessary when communicating with the projection exposure apparatuses 110 _{1 to} 110 _N and the like. The SDM server 130 is provided with an input / output device 131 including a display that is a man-machine interface for an operator and a pointing device such as a keyboard and a mouse. The SDM server 130 is externally connected with a drive device 132 for an information recording medium such as a CD (compact disc), DVD (digital versatile disc), MO (magneto-optical disc) or FD (flexible disc). ing. An information recording medium (hereinafter referred to as a CD) set in the drive device 132 includes a program corresponding to a processing algorithm shown in the flowchart of FIG. 6 (hereinafter referred to as “first program” for convenience). Other programs, and databases attached to these programs are recorded.

The SDM server 130 registers in a database in the storage device 140 distortion data (distortion data) of a projection image, which will be described later, sent periodically from each projection exposure apparatus 110 _i (i = 1 to N).

The terminal server 150 is configured as a gateway processor for absorbing the difference between the communication protocol in the LAN 170 and the communication protocol of the host computer system 160. With the function of the terminal server 150, communication between the host computer system 160 and the projection exposure apparatuses 110 _{1 to} 110 _N and the SDM server 130 connected to the LAN 170 becomes possible.

  The host computer system 160 is a manufacturing management system (MES: Manufacturing Execution System) including a large computer. Here, the manufacturing management system (MES) manages and analyzes all processes, equipment, conditions, and work data of each product flowing on the production line with a computer, thereby improving quality, improving yield and reducing work errors. It is a system that supports more efficient production.

  The host computer system 160 may be other than the MES, and for example, a dedicated computer may be used.

  As the LAN 170, either a bus type LAN or a ring type LAN can be used. In this embodiment, a carrier type medium access / contention detection (CSMA / CD) type bus type LAN of IEEE802 standard is used. ing.

Here, in order to obtain image distortion data sent from the main controller 50 of each projection exposure apparatus 110 _i (i = 1 to N) to the SDM server 130, a pattern periodically performed by each projection exposure apparatus 110 _i is obtained. Measurement of distortion (distortion) of a projected image and calculation of image distortion data (distortion data) based on the measurement result will be described. Here, the measurement of the distortion of the projection image and the like are performed periodically in consideration of changes in the imaging characteristics of the projection optical system over time.

  The measurement of the distortion of the projected image is performed in two stages: exposure using a test reticle and measurement of a resist image (transfer image) on the wafer after exposure.

First, light exposure using the test reticle, the case of the projection exposure apparatus 110 ₁ as an example. Here, as an example, a test reticle R1 as shown in FIG. 3 is used. The test reticle R1 of FIG. 3 has a pattern area PA1 having a width D1 (D1 is, for example, 125 mm) and a length L1 (L1 is, for example, 165 mm) at the center thereof, and the reticle is within the pattern area PA1. Centering on the center, n (n is, for example, 11 × 15 = 165) measurement marks M _{1 to} M _n are formed at a predetermined interval Δd (Δd is, for example, 10 mm) in the XY two-dimensional direction.

  When a test exposure instruction (distortion measurement instruction) is issued by the operator or the host computer system 160, the reticle R1 is conveyed by a reticle conveyance system (not shown), and is sucked and held on the reticle stage RST at the loading position. Thereafter, the above-described scanning exposure is performed on the first shot area on the wafer W, and the pattern of the pattern area PA1 of the reticle R1 is transferred by the scanning exposure method. Thereby, the exposure under the first exposure condition using the test reticle R1 is completed.

  Next, the main controller 50 changes the exposure conditions, such as the illumination conditions, in accordance with a predetermined procedure, and the second shot on the wafer W in the same manner as described above under the changed second exposure conditions. The pattern of the pattern area PA1 of the reticle R1 is transferred to the area. In the projection exposure apparatus of the present embodiment, for example, a plurality of diffractive optical elements that are replaceably arranged between the light source and the optical integrator in the illumination optical system and movable along the optical axis of the illumination optical system. An optical unit (molding optical system) including a prism and a zoom optical system is included. In the projection exposure apparatus of this embodiment, the optical unit can change the light amount distribution (the size and shape of the secondary light source) of the illumination light IL on the pupil plane of the illumination optical system, that is, the illumination condition of the reticle R. ing.

  In this way, when the transfer of the pattern of the pattern area PA1 of the reticle R1 to a different shot area on the wafer W under all the set exposure conditions is completed while changing the exposure conditions, this is indicated by the SDM server 130. Is displayed on the display of the input / output device 131 provided in FIG.

  Next, when a measurement instruction is given by the operator or the host computer system 160, the main controller 50 transfers the wafer W on the wafer holder to a C / D (not shown) using a wafer transfer system (not shown). Then, the wafer W is developed by C / D, and after the development, a resist image corresponding to the test reticle R1 is formed on the wafer W.

Next, in main controller 50, after the development of wafer W is loaded again onto the wafer holder using the wafer transfer system, the measurement mark in pattern area PA1 formed in the first shot area on wafer W is displayed. The resist images M _{1 to} M _n are sequentially detected using the alignment sensor 8. Then, based on the respective measured value and the measurement value of the corresponding wafer interferometer 18, sequentially calculates the position of the resist image of the measurement mark M ₁ ~M _n, their operation results, i.e. the measurement mark M ₁ The position coordinates of the resist images of .about.M _n on the stage coordinate system are stored in the internal memory in association with each measurement mark.

Thereafter, similarly, the position coordinates on the stage coordinate system of the resist images of the measurement marks M _{1 to} M _n in the pattern area PA1 formed in the second shot area, the third shot area,... On the wafer W are obtained. The position coordinates on the stage coordinate system are stored in the internal memory in association with each measurement mark.

In this way, the position coordinates of the resist images of the measurement marks M _{1 to} M _n formed under all the set different exposure conditions are stored in the internal memory.

Next, main controller 50 determines the position coordinates on the stage coordinate system of the registration images of the measurement marks M _{1 to} M _n stored in the internal memory, the reference point of each shot area, for example, the center point of the shot area. Each is converted into coordinate data in an ideal coordinate system (shot coordinate system) as the origin. Then, based on the difference between the coordinate data of the resist image of each measurement mark M _{1 to} M _n and the design position coordinate of the corresponding resist image, the position of the resist image of M _{1 to} M _n of each measurement mark. The shift amount is obtained for each shot area (that is, for each exposure condition).

  Then, main controller 50 generally performs the following processing for each shot area. That is, abnormal value data exceeding a predetermined allowable value is removed from the positional deviation amount data (raw data), and the average value of positional deviation amounts after the abnormal value data is removed is considered as a center shift amount. Remove from the total displacement (center shift correction). Next, the reticle manufacturing error (including pattern drawing error) is removed from the misalignment amount for which the center shift correction is completed in this way (reticle manufacturing error correction). Then, the alignment mark manufacturing error is removed from the misalignment amount corrected for the reticle manufacturing error (alignment mark manufacturing error correction). Next, the reticle rotation amount is removed from the misalignment amount corrected for the alignment mark manufacturing error (reticle rotation correction).

  The positional deviation amount data thus obtained is referred to as image distortion data in the following description. Main controller 50 obtains this image distortion data for each exposure condition, and transmits it to SDM server 130 together with each measurement time data. The SDM server 130 registers these data in the database in the storage device 140. Of course, the operator may input the image distortion data to the SDM server 130 via the input / output device 131.

Measurement of image distortion data similar to that described above is also periodically performed in the other projection exposure apparatuses 110 ₂ , 110 ₃ ,..., 110 _N , and the measurement results are sent to the SDM server 130, and the SDM server. 130, the data is registered in the database in the storage device 140. That is, the image distortion data is registered in the database of the storage device 140 for each projection exposure apparatus, each measurement time, and each exposure condition. Here, since the exposure condition is registered in the database with an ID for each exposure condition, the ID for each exposure condition is described as an exposure ID in the following description.

In the static exposure apparatuses 110 ₂ , 110 ₄ ,..., 110 _N , for example, a test reticle R2 as shown in FIG. 4 is used. The test reticle R2 shown in FIG. 4 has a pattern area PA2 having a width D2 (D2 is 110 mm, for example) and a length L2 (L2 is 110 mm, for example) at the center thereof, and the reticle is within the pattern area PA2. Centering on the center, m (m is, for example, 9 × 9 = 81) measurement marks M _{1 to} M _m are formed at a predetermined interval Δd (Δd is, for example, 10 mm) in the XY two-dimensional direction.

Further, the processing after the calculation of the position coordinates of the resist images of the measurement marks M _{1 to} M _m formed under all the different exposure conditions set in each projection exposure apparatus described above is not necessarily performed. There is no need for the main controller 50, and the SDM server 130 may be used. The image distortion data may be obtained using a reference wafer method.

In the lithography system 100, communication is performed between the main controller 50 of each projection exposure apparatus 110 _i and the host computer system 160 via the LAN 170 and the terminal server 150 at the end of the exposure process, and the main controller 50. The exposure history data of the corresponding projection exposure apparatus 110 _i is sent to the host computer system 160 together with the notification of the end of exposure, and is registered in a database in a storage device (not shown) by the host computer system 160. The exposure history data includes the name of the process program when the exposure command is processed, the name of the apparatus that performed the exposure process of the process corresponding to the process program (that is, the identification information of the projection exposure apparatus 110 _i ), the exposure ID, and the image. Information such as the distortion correction value and the date and time of exposure processing is included.

  Next, the operation of each part during the exposure of the wafer W by the lithography system 100 of the present embodiment configured as described above will be described with reference to FIGS. FIG. 5 shows a flowchart showing the processing algorithm of the host computer system 160, and FIG. 6 shows a flowchart showing the processing algorithm of the SDM server 130.

Incidentally, as a premise, the wafer W subject to exposure is already one or more layers of exposure is performed by the projection exposure apparatus 110 _1. It is assumed that the exposure history data of the wafer W is stored in the internal storage device of the host computer system 160. In addition, it is assumed that image distortion data information regarding each projection exposure apparatus 110 _i is stored in the storage device 140.

  The processing algorithm of the host computer system 160 shown in the flowchart of FIG. 5 starts when the preparation for exposure processing corresponding to a certain process program is started.

First, in step 204 in FIG. 5, inquiry information including a part of exposure history data of an exposed layer (reference layer: original process) for which overlay accuracy should be ensured in overlay exposure is sent via the terminal server 150 and the LAN 170. The SDM server 130 is inquired about a projection exposure apparatus suitable for performing exposure of the wafer W to be exposed. Here, a part of the above-described exposure history data includes the name of the process program when the exposure command is processed, and the apparatus that performed the exposure process of the process (original process) corresponding to the process program (here, projection as an example) the exposure apparatus 110 ₁ to) the device name, exposure ID and the image distortion correction value at the time of exposure of the original process of the apparatus, as well as information of the exposure processing date and time of the process corresponding to the process program.

  Then, the process proceeds to step 206 and waits for an answer to the inquiry from the SDM server.

  On the other hand, when receiving the above inquiry information, the SDM server 130 starts the processing (processing algorithm) of the first program shown in the flowchart of FIG. Prior to this, the CD storing the first program is set in the drive device 132, and the first program is loaded from the CD into the main memory of the SDM server 130.

First, in step 302 in FIG. 6, each projection exposure apparatus 110 _i stored in the storage device 140 is stored based on the name, the processing date and time, and the exposure ID of the original process in the received inquiry information. The image distortion data at the time of the original process exposure (image distortion data after the reticle rotation correction corresponding to the exposure apparatus, exposure ID, and date / time) is acquired.

In the next step 304, the image distortion data at the time of the original process exposure acquired in step 302 and an image distortion correction parameter (here, expressed by the following equation (1)) as an image distortion correction value included in the received inquiry information. The actual image distortion data at the time of exposure in the original process is calculated based on the values of the coefficients k _{1 to} k ₂₀ ) of the third-order model and the lens parameter file of the apparatus that performed the exposure process in the original process. Here, the lens parameter file means, for example, a table data file composed of an image distortion displacement amount (amount of change in the position of each measurement mark image) with respect to a unit drive amount (adjustment amount) for each drive element that drives the movable lens. To do.

  Here, when calculating the actual image distortion data at the time of exposure in the original process, the correction amount is put on all measurement points regardless of the definition of the comparison coordinates. Thereby, image distortion data after correction based on the image distortion correction parameter designated at the time of exposure (considered as distortion shape data by the projection optical system at the time of exposure) is obtained.

  In the next step 306, only the data of the coordinates defined in the comparison coordinate definition file are extracted from the image distortion data calculated in step 304. Here, the comparison coordinate definition file is determined in advance in consideration that the required exposure area is different for each finally manufactured semiconductor device and it is not always necessary to optimize the maximum area of the projection optical system. It has been.

  In the next step 307, a counter i indicating the number of the projection exposure apparatus is initialized to 1 (i ← 1).

In the next step 308, the latest image distortion data (corresponding to the exposure ID of the current process) of the i-th (here, the first) projection exposure apparatus 110 _i (here, 110 ₁ ) is searched in the storage device 140. And only the coordinate data defined in the comparison coordinate definition file is extracted from the acquired image distortion data.

By the above steps 302 to 308, it is assumed that the original process and the i th projection exposure apparatus 110 _i (here, the first projection exposure apparatus 110 ₁ ) are used as the current process processing apparatus. The image distortion (distortion) data for each coordinate (measurement point) defined in the comparison coordinate definition file is obtained. If there is no measurement data corresponding to the coordinates defined in the comparison coordinate definition file, the parameters in the tertiary model are calculated from the original image distortion data, and the estimated error amount at the coordinates without measurement data is calculated. Just do it.

In the next step 310, the image distortion data of the original process and the i-th projection exposure apparatus 110 _i (here, the first projection exposure apparatus 110 ₁ ) at the coordinates defined in the comparison coordinate definition file obtained as described above. Is calculated as a difference (image distortion difference data) from the image distortion data of the current process when it is assumed to be used as the current process processing apparatus.

In the next step 312, the shot shape error of the i-th projection exposure apparatus (here, the first projection exposure apparatus 110 ₁ ) is based on the image distortion difference data calculated in step 310 and the lens parameter file described above. That is, an adjustment amount that minimizes the amount of positional deviation of each measurement mark image as a whole (the amount of drive and inclination of the lens elements 27 and 29 of the imaging characteristic correction device in the optical axis direction, that is, the applied voltage to each drive element, etc.) Is obtained by a statistical operation such as a least square method. At this time, the image plane inclination amount of the i-th projection exposure apparatus may be calculated together.

  In the next step 314, it is determined whether or not the adjustment amount (and the image plane inclination amount) obtained above is within an allowable value. If this determination is affirmative, the process proceeds to step 316, and after calculating the amount of change in image distortion data when the projection optical system PL is actually adjusted using the adjustment amount calculated in step 312. Go to step 318.

  Note that the calculation of the above-described adjustment amount and the calculation of the change amount of the image distortion data based on the calculated adjustment amount are performed only for parameters that can be controlled by each projection exposure apparatus. Therefore, it is necessary to distinguish between a “batch exposure” type projection exposure apparatus and a “scanning exposure type” projection exposure apparatus.

In step 318, the value of the coefficient (image distortion correction parameters k _{1 to} k ₂₀ ) of the third-order model of the above equation (1) is minimized with respect to the change amount of the image distortion data of the i-th projection exposure apparatus obtained above. Each of the values is calculated by the square method, and the calculated image distortion correction parameter value is set as an image distortion correction value to be used by the i-th projection exposure apparatus during the exposure in the current process.

  In the next step 320, the final residual error after correction at each coordinate in the shot is obtained by subtracting the amount of change obtained in step 316 from the image distortion difference data obtained previously for the i-th projection exposure apparatus. After obtaining the data, the process proceeds to step 322.

  In step 322, it is determined whether or not the residual error data is within an allowable value at all coordinates. If the determination is affirmative, the process proceeds to the next step 324, and the i-th projection exposure apparatus is temporarily stored in the internal memory as the compatible apparatus, and then the process proceeds to step 326.

In step 326, it is determined whether or not the processing has been completed for all projection exposure apparatuses by determining whether or not the count value i of the counter i is N or more. Here, since i = 1 and only the processing for the first projection exposure apparatus 110 ₁ is completed, the determination here is denied, and after the counter i is incremented by 1 in step 328, the process returns to step 308, and thereafter The processing after step 308 is repeated until the determination at step 326 is affirmed. Thereby, the same processing as that of the projection exposure apparatus 110 ₁ described above is performed for each of the projection exposure apparatuses 110 _{2 to} 110 _N.

On the other hand, if the determination in step 314 or step 322 is negative, the i-th projection exposure apparatus 100 _i should not be an adapting apparatus, and jumps to step 326 without performing the subsequent processing. To do.

When the process for the last projection exposure apparatus 110 _N is completed and the determination in step 326 is affirmed, the process proceeds to step 330, and one or more temporarily stored as compatible devices in the internal memory in step 324 above. The host computer system 160 uses an image distortion correction value (calculated in step 318) and a residual error (calculated in step 320) to be used in each of the projection exposure apparatuses and the respective adaptive apparatuses as an answer to the inquiry. After the transmission to the LAN 170 and the terminal server 150, the series of processing ends.

  On the other hand, the host computer system 160 waits for an answer at step 206 in FIG. 5 while the process of the SDM server 130 is being performed, but the process of step 330 (answer to the inquiry) is performed. The determination at step 206 is affirmed, and the routine proceeds to step 208.

  In step 208, the current operation status, future operation schedule, and residual error of each received calibration apparatus are referred to, and the processing efficiency and exposure accuracy in the lithography system are comprehensively taken into consideration. A projection exposure apparatus that performs overlay exposure is selected. For example, when a plurality of compatible apparatuses are not currently operating, the host computer system 160 ensures processing efficiency by selecting an exposure apparatus that has the smallest residual error among them as an exposure apparatus that performs exposure in the current process. In addition, the exposure accuracy can be increased. Of course, when there is only one projection exposure apparatus that is an adapted apparatus, the projection exposure apparatus is selected as an exposure apparatus that performs exposure in the current process.

  Further, for example, when there are a plurality of projection exposure apparatuses that are adapted apparatuses, and the host computer system 160 is operating all of the adapted apparatuses, the current exposure operation is the earliest from the viewpoint of giving priority to throughput, for example. The projection exposure apparatus scheduled to be completed may be selected from the compatible apparatuses. If there is only one projection exposure apparatus that is not currently in operation, the projection exposure apparatus is selected from the same viewpoint. You may do it.

In the following description the case where the projection exposure apparatus 110 ₃ is selected as an example.

Then, in step 209, it is determined whether or not the selected apparatus (in this case, the projection exposure apparatus 110 ₃ ) has finished its operation. If this determination is negative, the operation waits for its operation to end. On the other hand, if the determination in step 209 is affirmative, that is, if the selected apparatus (in this case, the projection exposure apparatus 110 ₃ ) has been in operation from the beginning (not in operation) or has been in operation. In step 210, the main controller 50 of the selected apparatus (here, the projection exposure apparatus 110 ₃ ) is instructed to execute exposure including designation of an image distortion correction value. Thereafter, the process proceeds to step 212 and waits for notification of the end of exposure.

When the above-described exposure execution instruction is given, the main controller 50 of the selected projection exposure apparatus (here, the projection exposure apparatus 110 ₃ ) corrects its own imaging characteristics based on the received image distortion correction value. The apparatus is controlled to adjust the distortion of the projected image. Specifically, an applied voltage to each drive element corresponding to the image distortion correction value received from the host computer system 160 is calculated, and the applied voltage is applied to each drive element via the imaging characteristic control unit 12. Each lens element that can be driven is driven to adjust the distortion of the projection optical system.

Thereafter, an inside maximum allowable range of the difference between the distortion of the projection exposure apparatus 110 ₁ and the projection image of the original process, and the distortion of the projected image is adjusted, the projection exposure apparatus (here chosen is a projection exposure The apparatus 110 ₃ ) performs the exposure in the current process by the above-described scanning exposure method, and the pattern formed on the reticle R is transferred onto each shot area on the wafer W in an overlapping manner. Prior to the start of exposure, reticle alignment, baseline measurement of alignment sensor 8 and wafer alignment (EGA method, etc.) preparation work are performed. Position information of each shot area obtained as a result of wafer alignment and It goes without saying that the wafer W (wafer stage WST) is moved to the acceleration start position (scanning start position) for exposure of each shot area based on the measured baseline.

When the exposure of the current process by the selected projection exposure apparatus (here, the projection exposure apparatus 110 ₃ ) is completed, the main controller 50 to the LAN 170 and the terminal of the projection exposure apparatus (here, the projection exposure apparatus 110 ₃ ). The exposure history data is sent to the host computer system 160 via the server 150 together with the exposure completion notification.

On the other hand, the host computer system 160 is in the waiting state of step 212 in FIG. 5 while the exposure of the current process is being performed, but the determination of step 212 is affirmed by the notification of the end of exposure, Proceeding to step 214, the exposure history data received together with the notification of the end of exposure from the main controller 50 of the projection exposure apparatus selected here (projection exposure apparatus 110 ₃ ) in step 212 is stored in the database in the internal storage device. After registering, the series of processing ends.

As described above, according to the lithography system 100 according to the present embodiment, the host computer system 160 that manages the plurality of projection exposure apparatuses 110 _{1 to} 110 _N performs the image distortion correction used in the exposure of the original process. It also manages source process information including values. Then, in response to an inquiry from the host computer system 160 including at least a part of the original process information (see step 204 in FIG. 5), the SDM server 130 determines the current process for the distortion of the projection image during the exposure of the original process. One or a plurality of adapting apparatuses and the image distortion correction value to be used in each adapting apparatus in which the difference in distortion of the projected image at the time of exposure is an allowable value are calculated, and information on the calculation result is returned to the host computer system 160. (See steps 302 to 330 in FIG. 6). As a result, the host computer system 160 determines one or a plurality of (usually a plurality of) adapting devices and image distortion correction values to be used in each adapting device from the SDM server 130 regardless of lot identification information such as a lot name. get information. Then, the host computer system 160 selects one of the matching devices based on the information, and gives an image distortion correction value corresponding to the selected matching device to the matching device (see steps 208 and 210 in FIG. 6). ). As a result, exposure is performed in a state where the distortion of the projection image is corrected according to the original process based on the given image distortion correction value by the adaptive apparatus.

  As described above, in this embodiment, it is possible to perform distortion matching (distortion matching) of the projection image between the original process and the current process regardless of the lot identification information. Even in the case of a large variety of low-volume production, it is possible to perform distortion matching between the original process and the current process. As a result, the pattern of the original process and the pattern of the current process can be transferred with high accuracy to a plurality of shot areas on the wafer.

<< Second Embodiment >>
Next, a second embodiment of the present invention will be described. The lithography system of the second embodiment is partially configured in the same manner as the first embodiment described above, although the functions of the host computer system 160 and the SDM server 130 as a support device are partially different. Yes. Therefore, in the following, the above differences will be mainly described in order to avoid redundant description. For the same purpose, the same reference numerals are used for the same or equivalent components as those in the first embodiment described above, and detailed description thereof is omitted.

In the lithography system of the second embodiment, the LAN 170 and the terminal server 150 are connected between the main controller 50 of each projection exposure apparatus 110 _i (i = 1 to N) and the SDM server 130 at the end of the exposure process. Thus, the exposure history data of the corresponding projection exposure apparatus 110 _i is sent from the main controller 50 to the SDM server 130 and registered in the database in the storage device 140 by the SDM server 130. The exposure history data includes the name of the process program when the exposure command is processed, the name of the apparatus that performed the exposure process of the process corresponding to the process program (that is, the identification information of the projection exposure apparatus 110 _i ), the exposure ID, and the image. Information such as the distortion correction value and the date and time of exposure processing is included.

At the end of the exposure process, communication is performed between the main controller 50 of each projection exposure apparatus 110 _i and the host computer system 160 via the LAN 170 and the terminal server 150, and the exposure process ends from the main controller 50. The name of the process program when the exposure command is processed by the host computer system 160 that has been notified and received the notification, and the name of the apparatus that performed the exposure process of the process (original process) corresponding to the process program (ie, projection exposure apparatus) 110 _i identification information) and information such as the exposure processing date and time of the process corresponding to the process program are registered in a database in the internal storage device.

  Next, the operation of each part when the wafer W is exposed by the lithography system of the second embodiment will be described with reference to FIGS. FIG. 7 shows a flowchart showing the processing algorithm of the host computer system, and FIG. 8 shows a flowchart showing the processing algorithm of the SDM server 130.

Incidentally, as a premise, the wafer W subject to exposure is already one or more layers of exposure is performed by the projection exposure apparatus 110 _1. In addition, information such as the process program name of the process that becomes the original process, the name of the apparatus that performed the exposure process of the process corresponding to the process program (identification information of the projection exposure apparatus 110 _i ), and the date and time of the exposure process are as follows: It is assumed that it is stored in 160 internal storage devices. Further, it is assumed that image distortion data regarding each projection exposure apparatus 110 _i and exposure history data of the wafer W are stored in the storage device 140.

  The processing of the host computer system 160 shown in the flowchart of FIG. 7 starts when the preparation for exposure processing corresponding to a certain process program is started.

First, in step 404 of FIG. 7, the host computer system 160 determines information (process program name when processing the exposure command) on the exposed layer (reference layer: original process) whose overlay accuracy should be ensured in overlay exposure. , the apparatus was subjected to exposure processing step corresponding to the process program (based on step) (here, the projection exposure apparatus 110 ₁ as an example) of exposure processing date and time of steps corresponding to the apparatus name and the process program Inquiry information including information) is transmitted via the terminal server 150 and the LAN 170 to inquire the SDM server 130 about a projection exposure apparatus suitable for performing exposure of the wafer W to be exposed. Thereafter, the process proceeds to step 406 and waits for an answer to the inquiry from the SDM server.

  On the other hand, when receiving the above inquiry information, the SDM server 130 starts processing (processing algorithm) of a program (hereinafter referred to as “second program”) shown in the flowchart of FIG. Prior to this, the CD storing the second program is set in the drive device 132, and the second program is loaded from the CD into the main memory of the SDM server 130.

  First, in step 502 of FIG. 8, a database of exposure history data stored in the storage device 140 is searched based on the device name and processing date and time of the original process in the received inquiry information, Information on the exposure ID and the used image distortion correction value in the original process is acquired.

In the next step 503, a database of image distortion data related to each projection exposure apparatus 110 _i in the storage device 140 is searched based on the apparatus name, the processing date and time in the received inquiry information, and the exposure ID acquired in step 502. Then, image distortion data at the time of the original process exposure (image distortion data after reticle rotation correction corresponding to the apparatus that performed the exposure of the original process, the exposure ID and the date / time) is acquired.

In the next step 504, the acquired image distortion data at the time of the original process exposure and the image distortion correction parameter (here, the third order represented by the above-described equation (1)) as the image distortion correction value acquired in step 502 above. Based on the values of the model coefficients k _{1 to} k ₂₀ ) and the lens parameter file of the apparatus that performed the exposure process of the original process, actual image distortion data at the exposure of the original process is calculated.

  Also in this case, for the same reason as in step 304 described above, when calculating the actual image distortion data at the time of exposure in the original process, the correction amount is put on all the measurement points regardless of the comparison coordinate definition.

  In the next step 506, only the data of the coordinates defined in the comparison coordinate definition file are extracted from the image distortion data calculated in step 504.

  In the next step 507, a counter i indicating the number of the projection exposure apparatus is initialized to 1 (i ← 1). Thereafter, the processing (including determination) in steps 508 to 528 is repeated until the determination in step 526 is affirmed. Here, the processing (including determination) of step 508 to step 528 is the same as that of the above-described steps 308 to 328, and therefore detailed description of each step is omitted.

Thereby, in step 514 and step 522, each projection exposure apparatus 110 _i is judged step by step as to whether or not it is a compatible apparatus, and in step 514 and step 522 a positive judgment is made. Only the matching device will be stored in the internal memory at step 524.

Then, when the processing for the last projection exposure apparatus 110 _N is completed and the determination in step 526 is affirmed, the process proceeds to step 530, and one or more temporarily stored as compatible devices in the internal memory in step 524 above. An image distortion correction value (calculated in step 518) and residual error data (calculated in step 520) to be used in each projection exposure apparatus and each adaptive apparatus are used as a response to the inquiry, and the host computer system After transmitting the data to 160 via the LAN 170 and the terminal server 150, the series of processing ends.

  On the other hand, the host computer system 160 waits for an answer at step 406 in FIG. 7 while the process of the SDM server 130 is being performed, but the process of step 530 (answer to the inquiry) is performed. The determination at step 406 is affirmed, and the routine proceeds to step 408.

  In step 408, similarly to step 208 described above, a projection exposure apparatus that performs overlay exposure is selected from the received matching apparatuses.

In the following description the case where the projection exposure apparatus 110 ₃ is selected as an example.

Then, in step 409 and step 410 immediately if not running projection exposure apparatus 110 ₃ selected, and when the projection exposure apparatus 110 ₃ selected a running after completion of exposure operation, the selected the main control unit of the projection exposure apparatus 110 _3, and instructs the exposure execution including designation of the image distortion correction value. Thereafter, the process proceeds to step 412 to wait for notification of completion of exposure.

When the above exposure execution instruction is given, the main controller 50 of the selected exposure apparatus (here, the projection exposure apparatus 110 ₃ ), based on the received image distortion correction value, in the same manner as described above. The distortion of the projected image is adjusted by controlling the imaging characteristic correction apparatus.

Thereafter, the maximum value of the difference between the distortion of the projection exposure apparatus 110 ₁ and the projection image of the original process is within the allowable range, and the projection exposure apparatus 110 ₃ distortion of the projected image is adjusted, the scanning exposure method described above The exposure in the current process is performed, and the pattern formed on the reticle R is transferred onto each shot area on the wafer W in an overlapping manner. In this case as well, preparation operations for reticle alignment, baseline measurement of the alignment sensor 8, and wafer alignment (such as EGA method) are performed prior to the start of exposure, and each shot area obtained as a result of wafer alignment is performed. Of course, the wafer W (wafer stage WST) is moved to the acceleration start position (search start position) for exposure of each shot area based on the position information and the measured baseline.

When the exposure of the current process by the projection exposure apparatus 110 ₃ ends, the main control apparatus 50 of the projection exposure apparatus 110 ₃ notifies the host computer system 160 via the LAN 170 and the terminal server 150 of the end of exposure. The

On the other hand, while the host computer system 160 is in the waiting state of step 412 while the exposure of the current process is being performed, the determination of step 412 is affirmed by the notification of the end of exposure, and the process proceeds to step 414. willing, the device name and the process time of the projection shadow exposure apparatus 110 ₃ with process program name, after registering in a database in the storage device (not shown), and ends the series of processes.

  As described above, according to the lithography system of the second embodiment, the SDM server 130 determines the device name (a type of identification information) of the projection exposure apparatus that performed the exposure in the original process and the date and time when the exposure was performed. In response to an inquiry from the designated host computer system 160 (step 404 in FIG. 7), exposure history data (exposure name used for exposure in the original process, distortion correction value of the projection image used, and exposure) as exposure history information The difference between the projection image distortion at the exposure of the current process and the distortion of the projection image at the exposure of the original process is allowed using the image distortion data of each projection exposure apparatus and the image distortion data of each projection exposure apparatus. The adaptive device to be a value and the image distortion correction value to be used in each adaptive device are calculated, and information on the calculation result is returned to the host computer system 160 (steps 502 to 530 in FIG. 8).

  As described above, the SDM server 130 includes at least the distortion correction value of the projection image used at the time of the original process exposure from the exposure history data based on the apparatus name and the date and time without using the lot identification information such as the lot name. Using this information and the image distortion data for each projection exposure apparatus, the matching apparatus and the image distortion correction value to be used in each matching apparatus are calculated, and the information is returned to the host computer system 160. The

  Then, when there are a plurality of adapting apparatuses based on the information, the host computer system 160 selects one adapting apparatus (projection exposure apparatus) among them (step 408), and corresponds to the selected adapting apparatus. The image distortion correction value to be applied is given to the adapting device (step 410). Thus, exposure is performed in a state where the distortion of the projected image is corrected in accordance with the original process based on the image distortion correction value given by the selected matching apparatus. Therefore, in the present embodiment, it is possible to perform distortion matching between the original process and the current process even in the case of multi-product small-quantity production such as lot division from the middle, regardless of lot identification information. As a result, the pattern of the original process and the pattern of the current process can be transferred with high accuracy to a plurality of shot areas on the wafer.

<< Third Embodiment >>
Next, a third embodiment of the present invention will be described. The lithography system of the third embodiment is partially configured in the same manner as the first embodiment described above, although the functions of the host computer system 160 and the SDM server 130 as a support device are partially different. Yes. Therefore, in the following, in order to avoid redundant explanation, the explanation will be focused on the differences. For the same purpose, the same reference numerals are used for the same or equivalent components as those in the first embodiment described above, and detailed description thereof is omitted.

In the lithography system of the third embodiment, communication is performed between the main controller 50 of each projection exposure apparatus 110 _i and the host computer system 160 via the LAN 170 and the terminal server 150 at the end of the exposure process. The exposure history data of the corresponding projection exposure apparatus 110 _i is sent to the host computer system 160 together with the exposure end notification from the main controller 50, and is registered in the database in the internal storage device by the host computer system 160. . The exposure history data includes the name of the process program when the exposure command is processed, the name of the apparatus that performed the exposure process of the process corresponding to the process program (that is, the identification information of the projection exposure apparatus 110 _i ), the exposure ID, and the image. Information such as the distortion correction value and the exposure process date and time of the process is included.

  Next, processing of the host computer system 160 and the SDM server 130 configuring the lithography system of the third embodiment will be described with reference to FIGS. FIG. 9 shows a flowchart showing the processing algorithm of the host computer system, and FIG. 10 shows a flowchart showing the processing algorithm of the SDM server 130.

As a premise, it is assumed that the exposure history data of the wafer W to be exposed is stored as a database in the internal storage device of the host computer system 160. Further, it is assumed that image distortion data information regarding each projection exposure apparatus 110 _i is stored as a database in the storage device 140.

First, in step 602 of FIG. 9, the host computer system 160, the corresponding projection exposure apparatus 110 _k (k together with the notification of the end of exposure from the main control unit 50 of any of the projection exposure apparatus 110 _k is any 1~N By monitoring the exposure history data of (a), the process waits for the exposure of the process corresponding to the specific process program to end.

Then, the completion of the exposure step (former step) corresponding to the process program, the corresponding projection exposure apparatus 110 k _(k together with the notification of the end of exposure from the main controller 50 of the projection exposure apparatus 110 _k is, 1 to N When the exposure history data is sent via the LAN 170 and the terminal server 150, the process proceeds to step 604, and the sent exposure history data is stored in a database in an internal storage device (not shown). register.

In the next step 604, a part of the exposure history data of an exposed layer (reference layer: original process) for which overlay accuracy should be ensured in overlay exposure, and projection exposure that may be used in the next process. Inquiry information including an apparatus list (apparatus list) is transmitted via the terminal server 150 and the LAN 170 to inquire the SDM server 130 about an appropriate projection exposure apparatus for performing exposure of the wafer W to be exposed. Here, a part of the exposure history data, process the program name upon treatment of exposure command devices (here for performing exposure processing of the corresponding step in the process program, a projection exposure apparatus 110 ₁ as an example Information on the exposure process date and time of the process corresponding to the process program, and the exposure ID and image distortion correction value at the time of exposure of the original process of the apparatus.

  Then, the process proceeds to step 608 and waits for an answer to the inquiry from the SDM server 130.

  On the other hand, when receiving the above inquiry information, the SDM server 130 starts processing (processing algorithm) of a program (hereinafter referred to as “third program”) shown in the flowchart of FIG. Prior to this, the CD storing the third program is set in the drive device 132, and the third program is loaded from the CD into the main memory of the SDM server 130.

  In steps 702 to 728, the same processing as in steps 302 to 328 in the first embodiment described above is performed. Also in this case, the processing of the loop in steps 708 to 728 is repeated until the determination in step 726 is affirmed. However, in the present embodiment, since the above-described apparatus list is included in the inquiry information from the host computer system 160, the processing target after step 707 is the next of the N projection exposure apparatuses. There are M (M ≦ N) projection exposure apparatuses that may be used in the process. For this reason, identification numbers j of M projection exposure apparatuses that may be used in the next process are set to 1 to M, and a counter indicating the identification numbers is set to j. In this case, for example, the device of j = 1 does not necessarily match the device of i = 1.

  In addition, since the process of each step of the said step 702-step 728 is the same as the process of each step of the above-mentioned step 302-step 328, detailed description is abbreviate | omitted.

  Then, for the M projection exposure apparatuses that may be used in the next process, when the processing of Steps 707 to 728 is completed and the determination in Step 726 is affirmed, the process proceeds to Step 730.

  In step 730, the one or a plurality of projection exposure apparatuses temporarily stored in the internal memory as the matching apparatus in step 724 are sorted in ascending order of residual error data of each matching apparatus calculated in step 720. (Rearrange).

  In the next step 732, the list of matching devices after sorting and the image distortion correction value (calculated in step 718) to be used in each matching device are sent to the host computer system 160 as a response to the inquiry to the LAN 170 and the terminal. After the transmission through the server 150, the series of processing ends.

  On the other hand, the host computer system 160 waits for an answer at step 608 in FIG. 9 while the above-described processing of the SDM server 130 is being performed, but the processing at step 732 (answer to the inquiry) is performed. The determination at step 608 is affirmed, and the routine proceeds to step 610.

  In step 610, the received matching device list and the image distortion correction value of each matching device are stored in the internal memory, and then the process proceeds to step 612, where the exposure of the next process (current process) should be started. Wait for.

  Then, when it is time to start the exposure of the next process, the determination in step 612 is affirmed, and the process proceeds to step 614, where the current operation status and future operation schedule, etc., for each compatible device in the received compatible device list. The projection exposure apparatus that performs overlay exposure is selected from the received matching apparatuses in consideration of processing efficiency and exposure accuracy in the lithography system. At this time, since the compatible devices are listed in ascending order of the residual error data, in the host computer system 160, if there are a plurality of compatible devices that are not currently operating or will be exposed soon, the list of compatible devices is included. By selecting the upper projection exposure apparatus, it is possible to select a projection exposure apparatus that satisfies both the throughput and the overlay accuracy at the same time. As a result, the exposure accuracy can be improved while ensuring the processing efficiency. it can.

In the following description the case where the projection exposure apparatus 110 ₃ is selected as an example.

Then, in step 616, immediately if not running projection exposure apparatus 110 ₃ selected, and when the projection exposure apparatus 110 ₃ selected a running after completion of exposure operation, the selected projection exposure apparatus the main control unit 110 _3, and instructs the exposure execution including designation of the image distortion correction value. Thereafter, the process returns to step 602 and waits for the exposure of the process corresponding to the specific process program to be completed.

When the above exposure execution instruction is given, the main controller 50 of the selected exposure apparatus (here, the projection exposure apparatus 110 ₃ ), based on the received image distortion correction value, in the same manner as described above. The distortion of the projected image is adjusted by controlling the imaging characteristic correction apparatus.

Thereafter, the maximum value of the difference between the distortion of the projection exposure apparatus 110 ₁ and the projection image of the original process is within the allowable range, and the projection exposure apparatus 110 ₃ distortion of the projected image is adjusted, the scanning exposure method described above In the next process (current process), exposure is performed, and the pattern formed on the reticle R is transferred onto each shot area on the wafer W in a superimposed manner. Also in this case, prior to the start of exposure, the preparatory work for the wafer alignment (such as the EGA method) is performed, and based on the position information of each shot area obtained as a result of the wafer alignment and the measured baseline. Of course, the wafer W (wafer stage WST) is moved to the acceleration start position (search start position) for exposure of each shot area.

Thereafter, the exposure is completed, the exposure history data of the projection exposure apparatus 110 ₃ corresponding with the notification of the exposure completion from the main controller 50 of the projection exposure apparatus 110 _3, transmitted via the LAN170 and terminal server 150 The host computer 160 repeats the processing from step 604 onward.

  Here, in the processing of the host computer system 160 described above, in order to simplify the description, the description has been given focusing on a specific process program. However, in practice, a series of processing according to each of the plurality of process programs is performed. Are done in parallel. That is, processing similar to that shown in the flowchart of FIG. 9 corresponding to each process program is executed in parallel by the host computer system 160. The simultaneous and parallel processing in this case may be so-called time division processing or multitask processing.

  As described above, according to the lithography system of the third embodiment, the host computer system 160 makes an inquiry to the SDM server 130 after completion of exposure in a certain process (step 606) and answers to the inquiry. Information acquired from the SDM server 130 (information on the matching device list and the calculation result of the image distortion correction value to be used in each matching device) until the next process (current process) starts exposure. The data is stored in a device (not shown) (steps 610 and 612).

  In this case, the host computer system 160 uses the matching device list stored in the internal storage device and the information of the calculation result of the image distortion correction value to be used in each matching device when the exposure of the next process is to be started. Then, when one of the adaptation devices is selected (step 614) and the selected adaptation device is instructed to execute exposure (step 616), an image distortion correction value to be used by the adaptation device can be given. . As a result, the process is processed using the image distortion correction value optimum for the current process by the selected matching apparatus.

  Therefore, according to the lithography system of the third embodiment, even if the SDM server 130 goes down until the next process exposure is performed after obtaining the inquiry response, it is optimal for the next process (current process). It is possible to process the process using a correct image distortion correction value.

  In the third embodiment, the case has been described in which the host computer system 160 stores the information acquired from the SDM server 130 as an answer to the inquiry in its internal storage device. However, the present invention is not limited to this, and the SDM server 130 is not limited thereto. Any other device may be stored in any device connected to the LAN. In this way, the stored information can be retrieved even if the SDM server 130 goes down.

  In the first and second embodiments, as in the third embodiment, the SDM server 130 sorts the conforming devices in ascending order of residual error data as an answer to the inquiry from the host computer system 160. The compatible device list may be created, and the compatible device list may be used as a part of the answer information to the inquiry. In the first and second embodiments, similarly to the third embodiment, the host computer system 160 displays a list (projection list) of projection exposure apparatuses that may be used in the next step. Of course, it may be included in the inquiry information for the SDM server 130.

In each of the above embodiments, all the projection exposure apparatuses 110 _{1 to} 110 _N are grouped in advance into a group of projection exposure apparatuses in which the maximum value of the difference in distortion between the projection images is within an allowable range. The host computer system 160 includes at least a part of the projection exposure apparatuses in the group including the projection exposure apparatuses that have performed exposure in the original process as a list of projection exposure apparatuses that may be used in the next process. The list may be included in the inquiry information.

In each of the above embodiments, all of the projection exposure apparatuses 110 _{1 to} 110 _N have a function of correcting the distortion of the projected image. However, the present invention is not limited to this, and only a part of the projection exposure apparatuses 110 _{1 to} 110 _N. However, the distortion of the projected image may be adjustable. In this case, the SDM server 130 calculates an image distortion correction value to be used for the exposure in the current process only for such a projection exposure apparatus that can adjust the distortion of the projected image. When the host computer system 160 selects one of the projection exposure apparatuses capable of adjusting the distortion of the projection image as the adaptation apparatus (projection exposure apparatus) for performing the exposure in the current process, the selected adaptation An image distortion correction value is sent to the apparatus as part of the exposure command.

  In the case of a scanning exposure apparatus, the image distortion data at each measurement point described above includes the position of the stage system due to a shift in the speed ratio between the reticle stage RST and the wafer stage WST, a shift in the angle formed in the scanning direction, or the like. In some cases, a linear distortion component of control, that is, a so-called stage component is included. Therefore, when performing overlay exposure by removing such stage components, it is desirable to compare the image distortion data with each other after removing the stage components from the measured image distortion data.

  In addition, if there is a bend including unevenness, inclination, and curvature of an interferometer reflecting surface (the reflecting surface of the movable mirror in the above embodiment) provided on the reticle stage or wafer stage, this component is included in the image distortion data. Since it is contained, it is preferable to remove the bending component similarly.

  Also, an extended lens parameter file that is expanded by including the above-described stage component in the adjustment amount of the lens parameter file described above is created in advance, and the same processing as in each of the above embodiments is performed using the extended lens parameter file. It's also good. In this case, when the control amount of the non-zero stage component is calculated based on the calculated image distortion correction value, the main controller 50 determines the reticle stage according to the control amount when exposing each shot area. At least one of the speed ratio between the RST and the wafer stage WST and the angle formed by the scanning direction are adjusted.

  In each of the above embodiments, the distortion of the pattern image in each projection exposure apparatus is measured by actually transferring the pattern formed on the test reticle onto the wafer and measuring the pattern transferred onto the wafer. However, instead of this, the distortion of the pattern image in each projection exposure apparatus may be obtained based on the measurement result of the aerial image (projected image) of the pattern formed on the test reticle using the aerial image measuring device. good. In each of the above embodiments, the distortion of the original process is calculated based on the transfer image formed on the wafer. However, the present invention is not limited to this, and there are a plurality of marks that allow the distortion to be known on the layer. It is good also as calculating | requiring the distortion of an original process by arrange | positioning beforehand and measuring those marks.

  In the above embodiment, in order to obtain image distortion data of the scanning exposure apparatus, the pattern of the test reticle is transferred onto the wafer by the scanning exposure method, so that the image distortion data (dynamic Distortion data) was obtained, but the test reticle pattern was transferred onto the wafer by the static exposure method, and the rectangular exposure area of the projection optical system (that is, on the wafer) It is only necessary to obtain image distortion data (static distortion data) within the illumination light irradiation region.

  In each of the above embodiments, the case where the first, second, and third programs are loaded from the information recording medium such as a CD set in the drive device 132 to the main memory of the SDM server 130 and executed is described. Depending on the format of the program, the program may be temporarily installed in the storage device from the information recording medium, and the installed program may be loaded into the main memory and executed. Further, for example, the Internet may be used to download each of the above programs to the SDM server 130 via a communication network such as the LAN 170, and then the programs may be installed in a storage device or the like.

  In each of the above embodiments, the case where the first, second, and third programs are executed by the SDM server 130 that is a support device of the lithography system has been described. The microcomputer constituting the main controller 50 of one of the projection exposure apparatuses connected to the LAN 160 via the LAN 160 adopts a configuration for executing the first, second and third programs. Also good. That is, a configuration in which the main control device 50 of the single projection exposure apparatus also serves as the main role of the SDM server 130 of the above embodiment (the role of the support device of the lithography system) may be adopted. Such a configuration can be realized by connecting a drive device similar to the drive device 132 to the main control device 50 of the one projection exposure apparatus. In this case, the storage device 140 may be directly connected to the main control device 50 or may be connected via the LAN 170.

In each of the above embodiments, each projection exposure apparatus 110 _i (i = 1, 2,..., N), SDM server 130 and storage device 140, terminal server 150 and host computer system 160 are connected to a local area network ( (LAN) 170 has been described. However, the present invention is not limited to this, and the projection exposure apparatuses 110 _i (i = 1, 2,..., N), the SDM server 130, and the host computer system 160 are not limited thereto. A configuration may also be adopted in which persons communicate with each other via a wireless line.

  As the storage device 140, a magnetic storage device (magnetic disk, magnetic tape, etc.), an electrical storage device (semiconductor memory such as a battery / backup RAM), a magneto-optical storage device ( Needless to say, various storage forms such as a magneto-optical disk and the like (such as a digital audio tape (DAT)) can be employed.

In each of the above embodiments, the case where the scanning exposure apparatus and the static exposure apparatus are mixed in the plurality of projection exposure apparatuses 110 _{1 to} 110 _N constituting the lithography system has been described. It may be a scanning exposure apparatus or a static exposure apparatus. Further, exposure apparatuses having different resolving power or exposure apparatuses having different wavelengths of the illumination light IL may be mixed in the plurality of projection exposure apparatuses 110 _{1 to} 110 _N constituting the lithography system.

  In addition, the exposure target of the projection exposure apparatus is not limited to the wafer for semiconductor manufacturing as in the above-described embodiment, and for example, a square type for manufacturing a display apparatus such as a liquid crystal display element, a plasma display, and an organic EL. It can be widely applied to substrates for manufacturing glass plates, thin film magnetic heads, image sensors (CCDs, etc.), masks or reticles.

  In the projection exposure apparatus of the above embodiment, the magnification of the projection optical system may be not only a reduction system but also an equal magnification and an enlargement system, and the projection optical system PL is not only a refraction system but also a reflection system and a catadioptric system. Either of them may be used, and the projected image may be either an inverted image or an erect image.

As the projection optical system, when using far ultraviolet rays such as KrF or ArF excimer laser light, a material that transmits far ultraviolet rays such as quartz or fluorite is used as a glass material, and when using F ₂ laser light or the like, fluorite is used. It is necessary to use other fluoride crystals.

  In the above embodiment, the exposure illumination light of the projection exposure apparatus managed by the host computer system 160 is not limited to light with a wavelength of 100 nm or more, but light with a wavelength of less than 100 nm may be used. Absent. For example, in recent years, in order to expose a pattern of 70 nm or less, EUV (Extreme / Ultraviolet) light in a soft X-ray region (for example, a wavelength region of 5 to 15 nm) is generated using SOR or a plasma laser as a light source. Development of an EUV exposure apparatus using an all-reflection reduction optical system designed under the exposure wavelength (for example, 13.5 nm) and a reflective mask is underway. In this apparatus, since a configuration in which scanning exposure is performed by synchronously scanning the mask and the wafer using arc illumination is conceivable, such an apparatus can also be employed as a projection exposure apparatus constituting the lithography system of the present invention. Furthermore, an immersion type exposure apparatus or a step-and-stitch method disclosed in, for example, International Publication WO99 / 49504, in which a liquid (for example, pure water) is filled between the projection optical system PL and the wafer. Such an exposure apparatus can also be employed as a projection exposure apparatus constituting the lithography system of the present invention.

  An exposure apparatus using a charged particle beam such as an electron beam or an ion beam can also be used as a projection exposure apparatus constituting the lithography system of the present invention. The electron beam exposure apparatus may be any of a pencil beam method, a variable shaped beam method, a cell projection method, a blanking aperture array method, and a mask projection method.

  The semiconductor device includes a step of designing the function and performance of the device, a step of manufacturing a reticle based on the design step, a step of manufacturing a wafer from a silicon material, and each projection exposure apparatus ( It is manufactured through a step of transferring a reticle pattern to a wafer by a projection exposure apparatus selected as a conforming apparatus, a device assembly step (including a dicing process, a bonding process, and a packaging process), an inspection step, and the like.

  The lithography system, program and information recording medium, support apparatus, and exposure method of the present invention are suitable for superimposing and transferring a pattern onto a photosensitive object using a plurality of projection exposure apparatuses.

1 is a drawing schematically showing a configuration of a lithography system according to a first embodiment of the present invention. FIG. It is a diagram showing a schematic configuration of a projection exposure apparatus 110 ₁ in FIG. 1. It is a top view which shows an example of the test reticle used in the case of exposure for the measurement of image distortion with a scanning exposure apparatus. It is a top view which shows an example of the test reticle used in the case of the exposure for the measurement of image distortion with a static exposure apparatus. It is a flowchart which shows the processing algorithm of the host computer system which comprises the lithography system of 1st Embodiment. It is a flowchart which shows the processing algorithm of the SDM server which comprises the lithography system of 1st Embodiment. It is a flowchart which shows the processing algorithm of the host computer system which comprises the lithography system of 2nd Embodiment. It is a flowchart which shows the processing algorithm of the SDM server which comprises the lithography system of 2nd Embodiment. It is a flowchart which shows the processing algorithm of the host computer system which comprises the lithography system of 3rd Embodiment. It is a flowchart which shows the processing algorithm of the SDM server which comprises the lithography system of 3rd Embodiment.

Explanation of symbols

110 _{1 to} 110 _N ... projection exposure apparatus, 160 ... host computer system, 130 ... SDM server (image distortion calculation apparatus, support apparatus), 100 ... lithography system.

Claims (17)

A plurality of projection exposure apparatuses including at least one projection exposure apparatus capable of adjusting distortion of a projection image;
A host computer system for managing the plurality of projection exposure apparatuses and managing original process information including an image distortion correction value used in the exposure of the original process;
In response to an inquiry from the host computer system including at least part of the original process information, a difference between the projection image distortion at the current process exposure and the projection image distortion at the original process exposure is an allowable value. Calculating an image distortion correction value to be used in at least one of the plurality of projection exposure apparatuses, and a projection exposure apparatus capable of adjusting the distortion of the projected image among the adaptation apparatuses, A lithography system comprising: an image distortion calculation device that returns information to the host computer system.   The host computer system makes the inquiry to the image distortion arithmetic unit prior to the exposure of the current process, and the information acquired from the image distortion arithmetic device as a response to the inquiry starts the exposure of the current process. The lithography system according to claim 1, wherein the lithography system is stored in an apparatus other than the image distortion calculation apparatus until it is performed. A plurality of projection exposure apparatuses including at least one projection exposure apparatus capable of adjusting distortion of a projection image;
A host computer system that manages the plurality of projection exposure apparatuses and manages the identification information of the projection exposure apparatus that performed the exposure in the original process and the date and time when the exposure was performed;
In response to an inquiry from the host computer system that specifies the identification information of the projection exposure apparatus and the date and time of exposure, information on the name of the projection exposure apparatus, the date and time of exposure, and distortion of the projected image at the time of exposure Using the exposure history information including the image distortion data for each projection exposure apparatus, the difference in the distortion of the projection image at the exposure of the current process with respect to the distortion of the projection image at the exposure of the original process is an allowable value. An image distortion correction value to be used in at least one adapting apparatus of the plurality of projection exposure apparatuses and a projection exposure apparatus capable of adjusting the distortion of the projected image among the adapting apparatuses is calculated, and information on the calculation result A lithography system comprising: an image distortion calculation device that answers to the host computer system. A plurality of projection exposure apparatuses including at least one projection exposure apparatus capable of adjusting distortion of a projection image;
A host computer system for managing the plurality of projection exposure apparatuses;
In response to an inquiry from the host computer system, the difference in the distortion of the projection image at the exposure of the current process with respect to the distortion of the projection image at the exposure of the original process is an allowable value. An image for calculating an image distortion correction value to be used in at least one adapting apparatus and a projection exposure apparatus capable of adjusting the distortion of the projected image of the adapting apparatus, and returning information of the calculation result to the host computer system A strain calculation device;
The host computer system makes the inquiry to the image distortion arithmetic unit prior to the exposure in the current process, and the information acquired from the image distortion arithmetic device as a response to the inquiry starts the exposure in the current process. Until this is done, the information is stored in an apparatus other than the image distortion calculation apparatus.   5. The host computer system stores the inquiry and the information acquired as an answer to the inquiry during exposure by any of the projection exposure apparatuses. Lithography system.   6. The lithography system according to claim 4, wherein the host computer system makes the inquiry immediately after completion of exposure in a process immediately before the current process.   The information of the answer from the image distortion calculation device includes a matching device list sequentially arranged from a projection exposure device having a small difference in distortion of the projection image. A lithography system according to claim 1. A host for managing a plurality of projection exposure apparatuses including at least one projection exposure apparatus capable of adjusting distortion of a projected image and managing original process information including an image distortion correction value used in exposure of the original process A program for causing a computer connected to a computer system to execute predetermined processing,
In response to an inquiry from the host computer system including at least part of the original process information, a difference between the projection image distortion at the current process exposure and the projection image distortion at the original process exposure is an allowable value. Calculating an image distortion correction value to be used in at least one of the plurality of projection exposure apparatuses, and a projection exposure apparatus capable of adjusting distortion of the projected image among the adaptation apparatuses;
A program for causing the computer to execute a procedure for replying the calculation result information to the host computer system. Managing a plurality of projection exposure apparatuses including at least one projection exposure apparatus capable of adjusting the distortion of the projection image, and managing identification information of the projection exposure apparatus that performed the exposure in the original process and the date and time when the exposure was performed A program for causing a computer connected to a host computer system to execute predetermined processing,
In response to an inquiry from the host computer system that specifies the identification information of the projection exposure apparatus and the date and time of exposure, information on the name of the projection exposure apparatus, the date and time of exposure, and distortion of the projected image at the time of exposure Using the exposure history information including the image distortion data for each projection exposure apparatus, the difference in the distortion of the projection image at the exposure of the current process with respect to the distortion of the projection image at the exposure of the original process is an allowable value. A procedure for calculating an image distortion correction value to be used in at least one adaptation apparatus of the plurality of projection exposure apparatuses, and a projection exposure apparatus capable of adjusting distortion of a projection image among the adaptation apparatuses;
A program for causing the computer to execute a procedure for replying the calculation result information to the host computer system.   An information recording medium readable by a computer on which the program according to claim 8 is recorded. A plurality of projection exposure apparatuses including at least one projection exposure apparatus capable of adjusting the distortion of the projection image, and managing the plurality of projection exposure apparatuses, and image distortion correction values used in the exposure of the original process A lithography system support apparatus connected via a communication line to a host computer system for managing original process information including:
In response to an inquiry from the host computer system including at least part of the original process information, a difference between the projection image distortion at the current process exposure and the projection image distortion at the original process exposure is an allowable value. Calculating an image distortion correction value to be used in at least one of the plurality of projection exposure apparatuses, and a projection exposure apparatus capable of adjusting the distortion of the projected image among the adaptation apparatuses, An apparatus for supporting a lithography system, comprising: an arithmetic unit that returns information to the host computer system. A plurality of projection exposure apparatuses including at least one projection exposure apparatus capable of adjusting the distortion of the projected image, and the identification information of the projection exposure apparatus that has managed the plurality of projection exposure apparatuses and performed the exposure in the original process; A lithography system support apparatus connected via a communication line to a host computer system that manages the date and time when exposure was performed,
In response to an inquiry from the host computer system that specifies the identification information of the projection exposure apparatus and the date and time of exposure, information on the name of the projection exposure apparatus, the date and time of exposure, and distortion of the projected image at the time of exposure Using the exposure history information including the image distortion data for each projection exposure apparatus, the difference in the distortion of the projection image at the exposure of the current process with respect to the distortion of the projection image at the exposure of the original process is an allowable value. An image distortion correction value to be used in at least one adapting apparatus of the plurality of projection exposure apparatuses and a projection exposure apparatus capable of adjusting the distortion of the projected image among the adapting apparatuses is calculated, and information on the calculation result An apparatus for supporting a lithography system, comprising: an arithmetic unit that answers to the host computer system. A lithography system connected to each of a plurality of projection exposure apparatuses including at least one projection exposure apparatus capable of adjusting distortion of a projected image, and a host computer system managing the plurality of projection exposure apparatuses via a communication line Support device,
In response to an inquiry from the host computer system made prior to the exposure of the current process, a difference in the distortion of the projection image at the exposure of the current process with respect to the distortion of the projection image at the exposure of the original process becomes an allowable value. An image distortion correction value to be used in at least one adapting apparatus of the plurality of projection exposure apparatuses and a projection exposure apparatus capable of adjusting the distortion of the projected image among the adapting apparatuses is calculated, and information on the calculation result A lithography system support apparatus comprising an arithmetic unit that responds to the host computer system in order to store the information in an apparatus other than the own apparatus until exposure of the current process is started. A plurality of projection exposure apparatuses including at least one projection exposure apparatus capable of adjusting the distortion of the projection image, and managing the plurality of projection exposure apparatuses, and image distortion correction values used in the exposure of the original process An exposure method used in a system comprising: a host computer system that manages original process information including: a plurality of projection exposure apparatuses; and a support apparatus connected to each of the host computer systems via a communication line,
In response to an inquiry from the host computer system including at least a part of the original process information, the support apparatus determines a difference in the distortion of the projection image at the exposure of the current process with respect to the distortion of the projection image at the exposure of the original process. Of at least one adaptable device capable of adjusting the distortion of the projected image of the plurality of projection exposure apparatuses, and an image distortion correction value to be used in the adaptable apparatus, and information on the calculation result Replying to the host computer system;
In accordance with the answer, the host computer system selects a projection exposure apparatus that executes the exposure of the current process from the adaptive apparatuses, and exposure including designation of the image distortion correction value for the selected projection exposure apparatus Providing instructions; and
An exposure method including: a step in which the selected projection exposure apparatus adjusts the distortion of the projection image of the own apparatus based on the image distortion correction value, and performs exposure in the current process. A plurality of projection exposure apparatuses including at least one projection exposure apparatus capable of adjusting the distortion of the projected image, and the identification information of the projection exposure apparatus that has managed the plurality of projection exposure apparatuses and performed the exposure in the original process; An exposure method used in a system including a host computer system that manages the date and time when exposure was performed, and a plurality of projection exposure apparatuses and a support apparatus connected to the host computer system via a communication line, respectively. ,
In response to an inquiry from the host computer system that specifies the identification information of the projection exposure apparatus and the date and time when the exposure was performed, the support apparatus displays the projection exposure apparatus name, the date and time when the exposure was performed, and the projection image at the time of exposure. Using the exposure history information including information on the distortion of the image and the image distortion data for each projection exposure apparatus, the difference in the distortion of the projection image at the exposure of the current process with respect to the distortion of the projection image at the exposure of the original process is At least one adaptable device capable of adjusting the distortion of the projected image of the plurality of projection exposure apparatuses, which is an allowable value, and an image distortion correction value to be used in the adaptable apparatus are calculated, and information on the calculation result is obtained. Responding to the host computer system;
In accordance with the answer, the host computer system selects a projection exposure apparatus that executes the exposure of the current process from the adaptive apparatuses, and exposure including designation of the image distortion correction value for the selected projection exposure apparatus Providing instructions; and
An exposure method including: a step in which the selected projection exposure apparatus adjusts the distortion of the projection image of the own apparatus based on the image distortion correction value, and performs exposure in the current process. A plurality of projection exposure apparatuses including at least one projection exposure apparatus capable of adjusting the distortion of the projected image, a host computer system that manages the plurality of projection exposure apparatuses, the plurality of projection exposure apparatuses, and the host computer An exposure method used in a system including a support device connected to the system via a communication line,
In response to an inquiry made prior to the exposure of the current process from the host computer system, the support apparatus determines that the difference in the distortion of the projection image at the exposure of the current process with respect to the distortion of the projection image at the exposure of the original process. At least one adaptable device capable of adjusting the distortion of the projected image of the plurality of projection exposure apparatuses, which is an allowable value, and an image distortion correction value to be used in the adaptable apparatus are calculated, and information on the calculation result is obtained. Responding to the host computer system;
A step in which the host computer system stores the information of the calculation result in a device other than the support device after receiving the information from the support device until exposure of the current process is started;
When the host computer system starts exposure in the current process, the host computer system selects a projection exposure apparatus that performs exposure in the current process from the matching apparatuses included in the information of the calculation result, and the selected projection exposure apparatus Providing an exposure instruction including designation of the image distortion correction value to the image;
An exposure method including: a step in which the selected projection exposure apparatus adjusts the distortion of the projection image of the own apparatus based on the image distortion correction value, and performs exposure in the current process. The device manufacturing method including the lithography process in which the exposure method as described in any one of Claims 14-16 is performed.

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