Time imparting method and laser device

Abstract

A time-imparting method for imparting a time to a plurality of pulse data of a laser device that causes burst oscillation of pulse laser light, the time-imparting method comprising: receiving, by a first processor including a real-time system, a first light emission trigger signal from a laser irradiation device; the second processor measures the time interval between the previously received second light emission trigger signal and the first light emission trigger signal by means of a real-time system, receives the time interval from the first processor, and when the time interval is less than a set value, gives the pulse data of the pulse laser light corresponding to the first light emission trigger signal a time point at which the pulse data of the pulse laser light corresponding to the first light emission trigger signal is less than the set value. The time is obtained by adding a time interval to a time given for pulse data of the pulsed laser light corresponding to the second light emission trigger signal.

Description

Technical Field

[0001] The present disclosure relates to a time assigning method and a laser device. Background Art

[0002] In recent years, in semiconductor exposure devices, as semiconductor integrated circuits become smaller and more highly integrated, there is a demand for improved resolution. Therefore, the wavelength of light emitted from an exposure light source has been shortened. For example, as a gas laser device for exposure, a KrF excimer laser device that outputs a laser with a wavelength of about 248nm and an ArF excimer laser device that outputs a laser with a wavelength of about 193nm are used.

[0003] The spectral line width of the natural oscillation light of the KrF excimer laser device and the ArF excimer laser device is relatively wide, at 350 to 400 pm. Therefore, when a projection lens is constructed using a material that allows ultraviolet light such as KrF and ArF lasers to pass through, chromatic aberration may sometimes occur. As a result, the resolution may be reduced. Therefore, it is necessary to narrow the spectral line width of the laser output from the gas laser device to a level where chromatic aberration is invisible. Therefore, in order to narrow the spectral line width, a narrowing module (Line Narrowing Module: LNM) containing narrowing elements (etalon, grating, etc.) is sometimes provided in the laser resonator of the gas laser device. Hereinafter, a gas laser device that narrows the spectral line width will be referred to as a narrowed gas laser device.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2021-124966 Summary of the invention

[0007] A timing assigning method according to one aspect of the present disclosure is to assign timing to multiple pulse data of a laser device that causes a pulse laser to perform burst oscillation, wherein a first processor including a real-time system receives a first light-emitting trigger signal from a laser irradiation device, and uses the real-time system to measure the time interval between a previously received second light-emitting trigger signal and the first light-emitting trigger signal, and a second processor receives the time interval from the first processor, and when the time interval is less than a set value, assigns the following timing to the pulse data of the pulse laser corresponding to the first light-emitting trigger signal, which timing is the timing obtained by adding the time interval to the timing assigned to the pulse data of the pulse laser corresponding to the second light-emitting trigger signal.

[0008] The moment assignment method of another aspect of the present disclosure assigns moments to a plurality of pulse data of a laser device that causes a pulsed laser to oscillate in bursts. Among them, a first processor including a real-time system receives a first light emission trigger signal from a laser irradiation device, measures the time interval between the previously received second light emission trigger signal and the first light emission trigger signal using the real-time system. A second processor receives the time interval from the first processor. When no moment assignment signal is received from the laser irradiation device, the second processor assigns a moment obtained by adding the time interval to the moment of the pulse data of the pulsed laser corresponding to the second light emission trigger signal to the pulse data of the pulsed laser corresponding to the first light emission trigger signal.

[0009] The laser device of another aspect of the present disclosure outputs a pulsed laser in response to a light emission trigger signal received from a laser irradiation device. The laser device includes: a first processor including a real-time system, the first processor receives a first light emission trigger signal from the laser irradiation device, and measures the time interval between the previously received second light emission trigger signal and the first light emission trigger signal using the real-time system; and a second processor, which receives the time interval from the first processor. When the time interval is less than a set value, the second processor assigns a moment obtained by adding the time interval to the moment of the pulse data of the pulsed laser corresponding to the second light emission trigger signal to the pulse data of the pulsed laser corresponding to the first light emission trigger signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Hereinafter, several embodiments of the present disclosure will be described as examples with reference to the drawings.

[0011] Figure 1 Schematically shows the structure of a laser device of a comparative example.

[0012] Figure 2 Shows an example of burst oscillation of a laser device.

[0013] Figure 3 It is a flowchart showing an example of the processing steps of a data collection processor of a comparative example.

[0014] Figure 4 It is a chart showing an example of pulse data received by a data collection processor.

[0015] Figure 5 It is a chart showing an example of pulse data stored by a data collection processor.

[0016] Figure 6 It is a chart showing an example of burst data.

[0017] Figure 7 It is a timing diagram of the transmission and reception of pulse data in a laser device of a comparative example.

[0018] Figure 8 It is a graph showing the oscillation start times of each of the bursts No. 470 to 490.

[0019] Figure 9 It is a timing chart of the transmission and reception of pulse data in the laser device of Embodiment 1.

[0020] Figure 10 It is a chart showing an example of the pulse data received by the data collection processor of Embodiment 1.

[0021] Figure 11 It is a flowchart showing an example of the processing steps of the data collection processor of Embodiment 1.

[0022] Figure 12 It is a graph showing the oscillation start times of each of the bursts No. 470 to 490 in the laser device of Embodiment 1.

[0023] Figure 13 It schematically shows the structure of the laser device of Embodiment 2.

[0024] Figure 14 It is a timing chart of the transmission and reception of pulse data in the laser device of Embodiment 2.

[0025] Figure 15 It is a flowchart showing an example of the processing steps of the data collection processor of Embodiment 2. Detailed Embodiment

[0026] -Table of Contents-

[0027] 1. Explanation of Terms

[0028] 2. Explanation of the Laser Device of the Comparative Example

[0029] 2.1 Structure

[0030] 2.2 Operation

[0031] 2.3 Problems

[0032] 3. Embodiment 1

[0033] 3.1 Structure

[0034] 3.2 Operation

[0035] 3.3 Function / Effect

[0036] 4. Embodiment 2

[0037] 4.1 Structure

[0038] 4.2 Operation

[0039] 4.3 Function / Effect

[0040] 5. Others

[0041] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The embodiments described below show several examples of the present disclosure and do not limit the content of the present disclosure. In addition, the structures and operations described in each embodiment are not necessarily all essential to the structures and operations of the present disclosure. In addition, the same reference numerals are assigned to the same structural elements and repeated descriptions are omitted.

[0042] 1. Explanation of Terms

[0043] A "real-time system" is an operating system (RTOS: RealTime OS), a programmable logic device (PLD), etc. that have functions and characteristics for executing processes with time constraints. Real-time systems are widely used for the control of embedded systems such as industrial equipment and transportation machinery.

[0044] A "non-real-time OS" is a non-critical OS (Operating System) with a margin in processing time, also known as a GPOS (General Purpose Operating System). Generally speaking, a non-real-time OS has sufficient functions and excellent flexibility, and it can build a system at a relatively low cost.

[0045] 2. Explanation of the Laser Device in the Comparative Example

[0046] 2.1 Structure

[0047] Figure 1 The structure of the laser device 10 in the comparative example is schematically shown. The comparative example of the present disclosure is a method known only to the applicant, and is not a publicly known example admitted by the applicant. The laser device 10 includes an LNM 12, an output coupler (OC) 14, a cavity 16, a charger 18, a pulse power module (PPM) 20, a monitor module 22, a laser processor 24, and a data collection processor 26.

[0048] The LNM 12 includes prisms 30, 31, and a grating 32. The prisms 30, 31 are configured to expand the beam output from the cavity 16 and make the expanded beam incident on the grating 32 at a specified angle. The wavelength dispersion direction of the grating 32 is configured to be perpendicular to the discharge direction between the electrodes 34a, 34b in the cavity 16. The grating 32 is configured in a Littrow configuration such that the incident angle and the diffraction angle of the beam are the same angle.

[0049] OC14 is a partial mirror and is configured to form an optical resonator together with LNM12. The reflectivity of OC14 can be, for example, 20% to 30%.

[0050] The cavity 16 is arranged on the optical path of the optical resonator and includes a pair of electrodes 34a and 34b, and windows 36 and 37 through which pulsed laser light passes. The electrodes 34a and 34b are arranged to face each other in a direction perpendicular to Figure 1 the plane of the paper. In addition, Figure 1 the direction perpendicular to the plane of the paper in [] is defined as the V direction. Further, the traveling direction of the pulsed laser light output from OC14 is defined as the Z direction, and the direction perpendicular to the Z direction and the V direction is defined as the H direction.

[0051] An excimer laser gas is filled in the cavity 16. The excimer laser gas includes, for example, a noble gas, a halogen gas, and a buffer gas. The noble gas can also be Ar or Kr gas. The halogen gas can also be F2 gas. The buffer gas can also be Ne gas.

[0052] The charger 18 is electrically connected so as to charge a charging capacitor (not shown) in the PPM20. The PPM20 includes a switch 39 and a charging capacitor (not shown) and is connected to the electrode 34a via a feedthrough (not shown). The electrode 34b is connected to the grounded cavity 16.

[0053] The monitor module 22 includes a beam splitter BS1, a beam splitter BS2, an energy detector 42, and a spectrum detector 44. The beam splitter BS1 is arranged on the optical path of the pulsed laser light output from OC14 and is configured to cause the pulsed laser light reflected by the beam splitter BS1 to be incident on the beam splitter BS2.

[0054] The beam splitter BS2 is configured to cause the pulsed laser light reflected by the beam splitter BS2 to be incident on the energy detector 42 and cause the pulsed laser light transmitted through the beam splitter BS2 to be incident on the spectrum detector 44.

[0055] The energy detector 42 includes a condenser lens (not shown) and a photosensor. The photosensor can also be a photodiode having excellent high-speed responsiveness and resistance to ultraviolet light. The spectrum detector 44 can also be a spectroscope including an etalon (not shown) and an image sensor that measures interference fringes generated by the etalon.

[0056] The laser processor 24 is a processing device including a CPU (Central Processing Unit), a main storage device, and an auxiliary storage device. The laser processor 24 is a real-time system. The laser processor 24 functions as the main control system of the laser device 10.

[0057] The data collection processor 26 is a processing device including a CPU, a main storage device, and an auxiliary storage device. The OS of the data collection processor 26 is a non-real-time OS. The data collection processor 26 performs the following processing: collecting data such as pulse data related to the pulsed laser output from the laser device 10 and burst data generated in burst units that oscillate suddenly. The data collection processor 26 is connected to an external monitoring device 52 via a communication network 50.

[0058] The external monitoring device 52 includes a CPU, a main storage device, an auxiliary storage device, a display device such as a liquid crystal display (LCD) or an organic electroluminescence (EL) display, and an input device such as a keyboard or a voice input device. The external monitoring device 52 acquires the data collected by the data collection processor 26 and performs processing such as monitoring the operation of the laser device 10, presenting information of various data, data analysis, and presenting the analysis information.

[0059] In addition, it is possible that the external monitoring device 52 is connected to a centralized management system (not shown) via the communication network 50, and it is also possible to send data from the external monitoring device 52 to the centralized management system. The external monitoring device 52 is not limited to being connected to the laser device 10 and can be connected to multiple laser devices including Figure 1 other laser devices not shown in the figure.

[0060] The communication network 50 is a communication network capable of transmitting information by wire, wirelessly, or a combination thereof. The communication network 50 can also be a wide area network or a local area network.

[0061] The laser device 10 is connected to laser irradiation devices such as an exposure device 60 and a laser processing device (not shown). An Figure 1 exposure device 60 is illustrated in the figure. In this case, the laser processor 24 is connected to an exposure device processor 62 of the exposure device 60. The exposure device processor 62 is a processing device including a CPU, a main storage device, and an auxiliary storage device, and controls the operation of the exposure device 60.

[0062] 2.2 Operations

[0063] The laser processor 24 receives a light emission trigger signal and target data such as a target pulse energy and a target spectral width from laser irradiation devices such as the exposure device 60 and the laser processing device. The laser processor 24 sets the charging voltage of the charger 18 so that the pulse energy of the pulsed laser output from the laser device 10 becomes the target pulse energy.

[0064] Then, the laser processor 24 sends a light emission trigger signal to the PPM 20. Synchronously with this light emission trigger signal, the switch 39 in the PPM 20 is turned on, and the charge of the charge capacitor charged with the charging voltage Vhv is transferred via a feedthrough portion (not shown) or the like to the electrode 34a.

[0065] When a discharge occurs between the electrode 34a and the electrode 34b in the cavity 16, the laser gas is excited, and pulsed laser light with an ultraviolet wavelength of 150 nm to 380 nm, which is narrowed by the optical resonator composed of the OC 14 and the LNM 12, is output from the OC 14.

[0066] The pulsed laser light output from the OC 14 is incident on the monitor module 22. Then, the pulsed energy of the pulsed laser light is detected by the energy detector 42. In addition, the spectral line width and the like of the pulsed laser light are detected by the spectral detector 44. The data detected by the energy detector 42 and the spectral detector 44 are respectively sent to the laser processor 24. The laser processor 24 receives the light emission trigger signal and the target data from the exposure device 60 in a real-time state, and sends data such as the pulsed energy to the data collection processor 26.

[0067] The pulsed laser light that has passed through the monitor module 22 is incident on the exposure device 60.

[0068] Figure 2 An example of burst oscillation based on the laser device 10 is shown. As Figure 2 shown, the laser device 10 performs burst oscillation in which an oscillation period and a rest period are repeated. The oscillation period is a period during which pulsed laser light oscillates continuously. The rest period is a period during which the oscillation is stopped. In addition, the lengths of the oscillation period and the rest period do not need to be fixed.

[0069] Figure 3 It is a flowchart showing an example of the processing steps of the data collection processor 26 in the comparative example. In step S10, the data collection processor 26 receives pulse data from the laser processor 24 corresponding to the timing of the light emission trigger signal. The pulse data received by the data collection processor 26 includes at least one of pulsed energy, wavelength, and spectral line width.

[0070] Figure 4 An example of the pulse data received by the data collection processor 26 is shown. The data collection processor 26 receives pulse data including pulsed energy, wavelength, and spectral line width for each pulse. In addition, Figure 4 the pulse number (Pulse No.) shown represents the number within the oscillation period.

[0071] In Figure 3 step S20, the data collection processor 26 assigns a reception time to the received pulse data. At this time, the reception time assigned to the pulse data is assigned by a non-real-time OS.

[0072] Then, in step S30, the data collection processor 26 saves the pulse data together with the assigned time. Figure 5 An example of the pulse data saved by the data collection processor 26 is shown. The data collection processor 26 associates and saves the reception time of the pulse data with each pulse of the burst oscillation. For each oscillation period of the burst oscillation, the pulse data as shown is saved. Figure 5 The pulse data as shown.

[0073] In step S40, the data collection processor 26 determines whether a burst interval is detected. The burst interval is when the pulse number (pulse No.) included in the pulse data is "1". This is because the pulse number of each burst starts from "1". That is, the pulse number "1" means the initial pulse at the start of the oscillation of each burst. Therefore, the data collection processor 26 determines that it is a burst interval when it receives the pulse data with a pulse number of 1.

[0074] When the determination result in step S40 is a "yes" determination, that is, when the data collection processor 26 detects a burst interval, the data collection processor 26 proceeds to step S42.

[0075] In step S42, the data collection processor 26 calculates, for each block of the pulse group during the oscillation period of the burst oscillation, the oscillation start time, oscillation end time, average value, maximum value, minimum value of the pulse energy, average value, maximum value and minimum value of the wavelength, etc. of the burst oscillation, creates burst data including these data, and saves the burst data in association with the burst number (burst No.) in the auxiliary storage device. Figure 6 An example of the burst data is shown.

[0076] The oscillation start time can be the time assigned to the pulse data of the initial pulse in the burst, that is, the pulse number "1". The oscillation end time can be the time assigned to the pulse data of the final pulse in the burst. The data collection processor 26 can be configured to create and save burst data including at least one of the multiple data as shown. In addition, the data collection processor 26 is not limited to creating the burst data as shown, and can also create burst data including the deviation of the pulse energy, the deviation of the wavelength, the average value, maximum value, minimum value and deviation of the spectral line width, etc. Figure 6 The multiple data as shown. Figure 6 The burst data as shown, and can also create burst data including the deviation of the pulse energy, the deviation of the wavelength, the average value, maximum value, minimum value and deviation of the spectral line width, etc.

[0077] In step S44, the data collection processor 26 determines whether a data acquisition request has been received from the external monitoring device 52.

[0078] In the case where the determination result in step S44 is "Yes", that is, when the data collection processor 26 receives a data acquisition request from the external monitoring device 52, the data collection processor 26 proceeds to step S46.

[0079] In step S46, the data collection processor 26 sends pulse data and burst data to the external monitoring device 52.

[0080] After step S46, it proceeds to step S48.

[0081] In the case where the determination result in step S40 is "No", that is, when the data collection processor 26 does not detect a burst interval, the data collection processor 26 skips steps S42 to S46 and proceeds to step S48.

[0082] In addition, in the case where the determination result in step S44 is "No", that is, when the data collection processor 26 does not receive a data acquisition request from the external monitoring device 52, the data collection processor 26 skips step S46 and proceeds to step S48.

[0083] In step S48, the data collection processor 26 determines whether to end data collection. In the case where the determination result in step S48 is "No", that is, when the data collection processor 26 does not end data collection, the data collection processor 26 returns to step S10 and repeats the processing from step S10 to step S48 until data collection ends.

[0084] In the case where the determination result in step S48 is "Yes", that is, when the data collection processor 26 is to end data collection, end Figure 3 the flowchart.

[0085] The external monitoring device 52 sends a data acquisition request to the data collection processor 26, and acquires and saves the pulse data and burst data from the data collection processor 26 at an arbitrary timing.

[0086] The external monitoring device 52 displays the data acquired from the data collection processor 26 on the display device and performs data analysis.

[0087] 2.3 Problems

[0088] Figure 7 A timing chart showing the transmission and reception of pulse data in the laser device 10 of the comparative example is shown. The laser processor 24 sends the pulse data of each pulsed laser oscillated according to the light emission trigger signal to the data collection processor 26 at a timing synchronized with the light emission trigger signal.

[0089] The data collection processor 26 assigns the reception time to the data received from the laser processor 24 for each pulse. At this time, since the OS of the data collection processor 26 is a non-real-time OS, a delay occurs in the time assigned in response to the processing performed at the time of reception of the pulse data, and thus the accuracy of the time assigned for each pulse is sometimes insufficient. The problem of the present disclosure is to assign a time close to the timing of the light emission trigger signal to each pulse data in a non-real-time OS.

[0090] Figure 8 Shows the oscillation start times of each burst of burst Nos. 470 to 490. In addition, Figure 8 The oscillation period and the rest period of each of the shown bursts are fixed. However, in Figure 8 In the graph of, the line connecting the oscillation start times of each burst number is not a straight line. This is because a delay has occurred in the time (reception time) assigned to the pulse data.

[0091] In addition, in Figure 8 In the example of, the oscillation start times of burst No. 480 and burst No. 481 are the same. In this case, when making a judgment at the oscillation start time, the order of the bursts may be mistaken. This error affects the data analysis performed by the external monitoring device 52. For example, when analyzing the exposure result in the exposure device 60, data of a pulsed laser different from the pulsed laser for exposure is used for analysis.

[0092] 3. Embodiment 1

[0093] 3.1 Structure

[0094] The structure of the laser device according to Embodiment 1 can be the same as the structure of the laser device 10 described in Figure 1 .

[0095] 3.2 Operation

[0096] In the laser device according to Embodiment 1, the content of the processing executed by the data collection processor 26 is different from the processing of the comparative example ( Figure 3 ).

[0097] Figure 9A timing chart showing the transmission and reception of pulse data in the laser device of Embodiment 1. The laser processor 24 receives a light emission trigger signal from the exposure device 60 and measures the time interval of the light emission trigger signal. Sometimes the time interval of the light emission trigger signal is referred to as the "light emission trigger signal interval". Since the laser processor 24 is a real-time system, the measurement error of the measured light emission trigger signal interval is a small value. The data collection processor 26 receives pulse data including the light emission trigger signal interval from the laser processor 24 corresponding to the timing of the light emission trigger signal. The data collection processor 26 receives pulse data for each pulse.

[0098] The laser processor 24 is an example of the "first processor" in the present disclosure. The data collection processor 26 is an example of the "second processor" in the present disclosure. Each of the laser processor 24 and the data collection processor 26 is specifically configured or programmed to execute various processes included in the present disclosure.

[0099] Figure 10 An example of the pulse data received by the data collection processor 26 in Embodiment 1 is shown. The data collection processor 26 receives the time interval of the light emission trigger signal, the pulse energy, the wavelength, and the spectral line width for each pulse number corresponding to the light emission trigger signal.

[0100] The data collection processor 26 compares the light emission trigger signal interval included in the pulse data with a predetermined set value and determines whether the light emission trigger signal interval is equal to or greater than the set value. If the light emission trigger signal interval included in the pulse data is equal to or greater than the set value, the data collection processor 26 assigns a reception time to the pulse data. This reception time is assigned by a non-real-time OS.

[0101] In addition, if the time interval of the light emission trigger signal included in the received pulse data is not equal to or greater than the set value, the data collection processor 26 assigns the time obtained by adding the time interval of the light emission trigger signal to the time of the previous (immediately preceding) pulse data to the pulse data. The set value is larger than the delay of the time assigned by the non-real-time OS. The set value is, for example, 2 seconds to 85 seconds.

[0102] That is, when the time interval of the light emission trigger signal is less than the set value, the data collection processor 26 assigns the following time to the received pulse data, which is the time obtained by adding the received time interval to the time assigned to the pulse data of the pulsed laser corresponding to the previous light emission trigger signal (see Figure 9 ).

[0103] For example, in the Figure 9 shown burst oscillation, assume that one light emission trigger signal received immediately before the first (leftmost) light emission trigger signal from the left is related to Figure 9The light emission trigger signal corresponding to the final pulse in the oscillation period immediately before the pause period (e.g., a pause period of 2 seconds or more) not shown in the figure.

[0104] In this case, when the data collection processor 26 receives the pulse data of the pulsed laser output in response to Figure 9 the first light emission trigger signal from the left, since the time interval between the first light emission trigger signal and the previous light emission trigger signal is equal to or greater than the set value, the data collection processor 26 assigns the reception time of the pulse data of the pulsed laser corresponding to the first light emission trigger signal through the non-real-time OS. In this case, the first light emission trigger signal is an example of the "first light emission trigger signal" in the present disclosure, and the previous light emission trigger signal not shown in the figure is an example of the "second light emission trigger signal" in the present disclosure.

[0105] Next, when the data collection processor 26 receives the pulse data of the pulsed laser output in response to Figure 9 the second light emission trigger signal from the left, since the time interval between the second light emission trigger signal and the previously received first light emission trigger signal is smaller than the set value, the data collection processor 26 assigns the time obtained by adding the time interval to the time of the previously received pulse data. In this case, the second light emission trigger signal is an example of the "first light emission trigger signal" in the present disclosure, and the first light emission trigger signal is an example of the "second light emission trigger signal" in the present disclosure. Thereafter, the same applies to the pulse data corresponding to each pulse in the oscillation period of the burst oscillation, and the time obtained by adding the time interval of the light emission trigger signal to the time of the previous pulse data is assigned.

[0106] The set value can also be specified in consideration of the time required to switch the wafer to be exposed. It is preferable to specify the set value of the wafer in such a way as to avoid assigning the time through the non-real-time OS in the middle of the process of exposing the same wafer. For example, in a normal semiconductor manufacturing process, the time interval of the light emission trigger signal when exposing the same wafer is less than 2 seconds. Therefore, by setting the set value to 2 seconds, it is possible to assign the reception time of the pulse data to the pulse data through the non-real-time OS at the timing of changing the wafer to be exposed.

[0107] Figure 11 is a flowchart showing an example of the processing steps of the data collection processor 26 according to Embodiment 1. Regarding Figure 11 , the differences from the Figure 3 flowchart will be described. Figure 11 The flowchart shown instead of Figure 3 step S10 includes step S11 and includes step S12 between step S11 and step S20. And, Figure 11The flowchart shown includes step S14 branched from the determination process of step S12.

[0108] In step S11, the data collection processor 26 receives pulse data including data on the emission trigger signal interval from the laser processor 24 at the timing corresponding to the emission trigger signal.

[0109] Then, in step S12, the data collection processor 26 determines whether the emission trigger signal interval is equal to or greater than a set value.

[0110] When the determination result in step S12 is "Yes", that is, when the emission trigger signal interval is equal to or greater than the set value, the data collection processor 26 proceeds to step S20.

[0111] When the determination result in step S12 is "No", that is, when the emission trigger signal interval is less than the set value, the data collection processor 26 proceeds to step S14.

[0112] In step S14, the data collection processor 26 assigns the time obtained by adding the time interval of the emission trigger signal to the time of the immediately preceding pulse data to the pulse data. After step S14, the data collection processor 26 proceeds to step S30.

[0113] Other operations can be the Figure 1 same.

[0114] Thus, instead of the Figure 5 "reception time" described, the time obtained by adding the time interval to the reception time or the time of the previous pulse data is assigned. Figure 10 and Figure 11 The time assignment method of Embodiment 1 described is an example of the "time assignment method" in the present disclosure.

[0115] 3.3 Function / Effect

[0116] Figure 12 Shows the oscillation start times of each burst of Burst No. 470 to 490 in the laser device of Embodiment 1. As Figure 12 shown, the line connecting the oscillation start times for each burst number forms a straight line. With such oscillation start times, the order of the bursts will not be mistaken.

[0117] In addition, in Embodiment 1, the case where the data collection processor 26 assigns the pulse data received from the laser processor 24 at the reception time by the non-real-time OS is the case where the time interval of the light emission trigger signal is equal to or greater than the set value, and is the case where the time interval of the light emission trigger signal is greater than the delay of the time assigned by the non-real-time OS. Therefore, according to the time assignment method of Embodiment 1, the times assigned to the multiple pulse data are not the same, and the order of the bursts is not mistaken.

[0118] According to Embodiment 1, it is possible to assign to each pulse data a time close to the timing of the light emission trigger signal in a general-purpose OS, that is, a non-real-time OS. The data collection processor 26 that executes the time assignment method of Embodiment 1 can assign appropriate times to the pulse data of the pulsed laser output in response to the light emission trigger signal, and can collect and accumulate more accurate logs compared with the structure of the comparative example. This contributes to strengthening the monitoring function in the external monitoring device 52.

[0119] 4. Embodiment 2

[0120] 4.1 Structure

[0121] Figure 13 Schematically shows the structure of the laser device 10B of Embodiment 2. Regarding Figure 13 , Figure 1 the differences from the structure shown are described.

[0122] The laser device 10B of Embodiment 2 is different from that of Embodiment 1 in that a time assignment request is sent from a laser irradiation device such as an exposure device 60 or a laser processing device to the laser device 10B. Figure 13 Shows the transmission path of the signal of the time assignment request sent from the exposure device 60 to the data collection processor 26 via the laser processor 24. The signal of the time assignment request is called a time assignment signal. Other structures can be the same as Figure 1 .

[0123] 4.2 Operation

[0124] The time assignment signal is a signal sent when it is desired to re-obtain the time based on the non-real-time OS. The data collection processor 26 receives the time assignment signal from the exposure device 60 or the laser processor 24, and in response to the received time assignment request, assigns the time of the non-real-time OS to the pulse data. When the data collection processor 26 does not receive the time assignment signal, it assigns accurate times to each pulse data by adding the time interval of the light emission trigger signal to the time of the pulse data related to the previous reception.

[0125] Figure 14 Shows the timing chart of the transmission and reception of the pulse data in the laser device 10B of Embodiment 2. RegardingFigure 14 , differences from Embodiment 1 described in Figure 9 will be described. In Embodiment 1, the time interval of the light emission trigger signal is compared with the set value, and if the time exceeds the set value, the time of the non-real-time OS is automatically assigned. In contrast, in Embodiment 2, the difference from Embodiment 1 is that the time of the non-real-time OS is assigned in response to the reception of the time assignment signal.

[0126] In Figure 14 , examples of the case where the time assignment signal is received during the burst oscillation period and the case where the time assignment signal is received during the rest period are shown. In addition, even if the time assignment signal is received and the reception time is assigned to the data when the time interval of the light emission trigger signal is short, such as during the burst oscillation, there will be a delay in the assigned time, but the possibility of being assigned the same time as the immediately preceding data is small.

[0127] Furthermore, in the case where the time interval of the light emission trigger signal is short, such as during the burst oscillation, it is also possible to return an error and not accept the time assignment request. The case where the time interval of the light emission trigger signal is short can be, for example, a case where the time interval is 2 seconds or less.

[0128] Figure 15 is a flowchart showing an example of the processing steps of the data collection processor 26 in Embodiment 2. Regarding Figure 15 , differences from the Figure 11 flowchart will be described. Figure 15 The flowchart shown in Figure 11 includes step S13 instead of step S12.

[0129] In step S13, the data collection processor 26 determines whether a time assignment signal is received from the laser irradiation device. The exposure device 60 is an example of the laser irradiation device. The laser irradiation device is not limited to the exposure device 60 and can also be a laser processing device.

[0130] When the determination result in step S13 is "yes", that is, when the data collection processor 26 receives the time assignment signal, the data collection processor 26 proceeds to step S20. In step S20, the data collection processor 26 assigns the reception time to the next received pulse data. The data collection processor 26 can also receive the time assignment signal at the timing of the burst interval.

[0131] When the determination result in step S13 is "no", that is, when the data collection processor 26 does not receive the time assignment signal, the data collection processor 26 proceeds to step S14.

[0132] Other operations are the same as those in the Figure 11 flowchart.

[0133] 4.3 Function / Effect

[0134] According to Embodiment 2, the same effects as those of Embodiment 1 can be obtained. Further, according to Embodiment 2, by designating the time of the non-real-time OS to the pulse data by a laser irradiation device such as the exposure device 60, it is possible to assign a correct time with real-time property within an arbitrary range of the light emission instruction from the laser irradiation device.

[0135] 5. Others

[0136] The above description is not restrictive but merely illustrative. Therefore, those skilled in the art will understand that modifications can be made to the embodiments of the present disclosure without departing from the claims. In addition, those skilled in the art will also understand that the embodiments of the present disclosure can be used in combination.

[0137] Unless otherwise clearly stated, the terms used throughout this specification and the claims should be construed as "non-limiting" terms. For example, terms such as "comprising," "having," "including," and "possessing" should be construed as "not excluding structural elements other than those recited." In addition, the modifier "a" should be construed to mean "at least one" or "one or more than one." Further, a term such as "at least one of A, B, and C" should be construed as "A," "B," "C," "A + B," "A + C," "B + C," or "A + B + C." And it should be construed to also include combinations with parts other than A, B, and C.

Claims

1. A moment assignment method for assigning moments to a plurality of pulse data of a laser device that causes pulsed laser to perform burst oscillation, wherein a first processor including a real-time system receives a first light emission trigger signal from a laser irradiation device, and measures a time interval between the previously received second light emission trigger signal and the first light emission trigger signal using the real-time system, a second processor receives the time interval from the first processor, and when the time interval is less than a set value, assigns a moment to the pulse data of the pulsed laser corresponding to the first light emission trigger signal, and the moment is obtained by adding the time interval to the moment assigned to the pulse data of the pulsed laser corresponding to the second light emission trigger signal.

2. The moment assignment method according to claim 1, wherein the second processor obtains the pulse data for each pulse.

3. The moment assignment method according to claim 1, wherein the pulse data includes at least one of pulse energy, wavelength, and spectral line width.

4. The moment assignment method according to claim 1, wherein the second processor receives the pulse data from the first processor.

5. The moment assignment method according to claim 1, wherein the second processor includes a non-real-time OS, the second processor receives the pulse data of the pulsed laser corresponding to the first light emission trigger signal from the first processor, and when the time interval is greater than or equal to the set value, assigns the moment when the non-real-time OS receives the pulse data to the pulse data of the pulsed laser corresponding to the first light emission trigger signal.

6. The moment assignment method according to claim 1, wherein the set value is 2 seconds to 85 seconds.

7. The moment assignment method according to claim 1, wherein the laser irradiation device is an exposure device or a laser processing device.

8. The moment assignment method according to claim 1, wherein when the second processor detects the burst interval of the burst oscillation, the second processor creates burst data including at least one of the oscillation start moment, oscillation end moment, average value of pulse energy, maximum value, minimum value, average value of wavelength, maximum value, and minimum value of the pulse group during the oscillation period of the burst oscillation based on the pulse data of the pulse group during the oscillation period of the burst oscillation.

9. A moment assignment method for assigning moments to a plurality of pulse data of a laser device that causes pulsed laser to perform burst oscillation, wherein a first processor including a real-time system receives a first light emission trigger signal from a laser irradiation device, and measures a time interval between the previously received second light emission trigger signal and the first light emission trigger signal using the real-time system, a second processor receives the time interval from the first processor, and when no moment assignment signal is received from the laser irradiation device, the second processor assigns a moment to the pulse data of the pulsed laser corresponding to the first light emission trigger signal, and the moment is obtained by adding the time interval to the moment of the pulse data of the pulsed laser corresponding to the second light emission trigger signal.

10. The moment assignment method according to claim 9, wherein The second processor obtains the pulse data for each pulse.

11. The timing assignment method according to claim 9, wherein the pulse data includes at least one of pulse energy, wavelength, and spectral line width.

12. The timing assignment method according to claim 9, wherein the second processor receives the pulse data from the first processor.

13. The timing assignment method according to claim 9, wherein the second processor includes a non-real-time OS, the second processor receives the pulse data of the pulsed laser corresponding to the first light emission trigger signal from the first processor, and when the timing assignment signal is received, assigns the time when the non-real-time OS receives the pulse data to the pulse data of the pulsed laser corresponding to the first light emission trigger signal.

14. The timing assignment method according to claim 9, wherein the laser irradiation device is an exposure device or a laser processing device.

15. A laser device that outputs pulsed laser light in response to a light emission trigger signal received from a laser irradiation device, wherein, The laser device includes: a first processor including a real-time system, the first processor receives a first light emission trigger signal from the laser irradiation device, and measures the time interval between the previously received second light emission trigger signal and the first light emission trigger signal using the real-time system; and a second processor that receives the time interval from the first processor, and when the time interval is less than a set value, assigns the time obtained by adding the time interval to the time of the pulse data of the pulsed laser corresponding to the second light emission trigger signal to the pulse data of the pulsed laser corresponding to the first light emission trigger signal.

16. The laser device according to claim 15, wherein the second processor obtains the pulse data for each pulse.

17. The laser device according to claim 15, wherein the pulse data includes at least one of pulse energy, wavelength, and spectral line width.

18. The laser device according to claim 15, wherein the second processor includes a non-real-time OS, the second processor receives the pulse data of the pulsed laser corresponding to the first light emission trigger signal from the first processor, and when the time interval is greater than or equal to the set value, assigns the time when the non-real-time OS receives the pulse data to the pulse data of the pulsed laser corresponding to the first light emission trigger signal.

19. The laser device according to claim 15, wherein the set value is 2 seconds to 85 seconds.

20. The laser device according to claim 15, wherein the laser irradiation device is an exposure device or a laser processing device.

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