Semiconductor processing equipment

Abstract

A semiconductor processing apparatus includes a controller configured to receive a determination signal representative of a first position at which a laser beam is expected to irradiate a first droplet; calculating a second position at which the laser beam irradiates the first droplet; and generate a measurement signal representative of the second position; generating at least one of a first error signal and a second error signal according to the determination signal and the measurement signal; generating a feed-forward signal according to at least one of the first error signal and the second error signal; generating a feedback signal according to the feed-forward signal and a first position difference between the first position and the second position in the first direction; and determining a second emission time point for a second specific period of time to which the second droplet is supplied by adding the feedback signal to the reference signal.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to Korean Patent Application No. 10-2024-0091589, filed on July 11, 2024, with the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] The exemplary embodiments of this disclosure relate to a semiconductor processing apparatus. Background Technology

[0004] Semiconductor processing can include photolithography, etching, deposition, and other processes to form multiple layers on a substrate, and multiple patterns can be formed in each of the multiple layers. As the linewidths of the multiple patterns become finer and the spacing between them becomes narrower, photolithography processes using relatively short wavelength bands of light (such as extreme ultraviolet (EUV) light) have been proposed. Semiconductor processing equipment that performs photolithography using EUV light can include a light source system that generates EUV light. To improve and consistently maintain the yield and productivity of semiconductor processing performed in the semiconductor processing equipment, it may be necessary to increase the energy of the EUV light generated by the light source system. Summary of the Invention

[0005] An exemplary embodiment of this disclosure provides a semiconductor processing apparatus that can generate extreme ultraviolet light with improved energy levels by controlling the timing at which a laser beam irradiates a droplet.

[0006] According to one aspect of this disclosure, a semiconductor processing apparatus includes a droplet supplier configured to form a first droplet and supply the first droplet into a chamber along a first direction during a first specific time period; a light source generator configured to emit a laser beam in a second direction perpendicular to the first direction at a first emission time point, such that extreme ultraviolet light is generated from the first droplet; a position sensor configured to be adjacent to the chamber; and a controller configured to receive a determination signal including first information indicating a first position where the laser beam is expected to irradiate the first droplet; calculate a second position where the laser beam irradiates the first droplet using the output of the position sensor; generate a measurement signal including second information indicating the second position; generate at least one of a first error signal and a second error signal based on the determination signal and the measurement signal; generate a feedforward signal based on at least one of the first error signal and the second error signal; generate a feedback signal based on the feedforward signal and a first position difference in the first direction between the first position and the second position; and determine a second emission time point of a second specific time period by adding the feedback signal to a reference signal, during which the droplet supplier supplies the second droplet into the chamber, the reference signal including information indicating a reference time point in the first specific time period.

[0007] According to one aspect of this disclosure, a semiconductor processing apparatus includes: a droplet feeder configured to form a droplet and supply the droplet into a chamber along a first direction; a light source generator configured to emit a laser beam in a second direction perpendicular to the first direction at a first emission time point, such that extreme ultraviolet light is generated from the droplet; a position sensor configured to be adjacent to the chamber; and a controller configured to receive a determination signal and determine a second emission time point, the determination signal including information indicating a first position where the droplet is expected to be irradiated by the laser beam. The controller is further configured to use the output of the position sensor to calculate a measurement signal including information indicating a second position where the laser beam irradiates the droplet, and to generate an error signal including information indicating a difference between the first position of the determination signal and the second position of the measurement signal. The determination signal, the measurement signal, and the error signal include position values ​​in the first direction, the second direction, and a third direction perpendicular to the first and second directions, respectively, within a specific time period. The controller is further configured to use at least one of the position value of the error signal in the second direction and the position value of the error signal in the third direction to calculate a position compensation value in the first direction. The second transmission time point is determined by determining the position value of the signal in the first direction, measuring the position value of the signal in the first direction, and the position compensation value in the first direction.

[0008] According to one aspect of this disclosure, a semiconductor processing apparatus includes: a droplet supplier configured to form a droplet and supply the droplet into a chamber in a first direction; a light source generator configured to emit a laser beam in a second direction perpendicular to the first direction at a first emission time point, such that extreme ultraviolet light is generated from the droplet; a position sensor configured to be adjacent to the chamber; and a controller configured to receive a determination signal and determine a second emission time point, the determination signal including information indicating a first position where the droplet is expected to be irradiated by the laser beam. The controller is further configured to use the output of the position sensor to calculate a measurement signal including information indicating a second position where the droplet is irradiated by the laser beam, and to calculate an error signal including information indicating a difference between the first position of the determination signal and the second position of the measurement signal. The determination signal, the measurement signal, and the error signal include position values ​​in the first direction, the second direction, and a third direction perpendicular to the first and second directions, respectively, within a specific time period. The position value of the determination signal in the first direction is controlled such that, by using the position values ​​of the error signal in the first direction to the third direction to determine the second emission time point, the energy of the extreme ultraviolet light increases at the position value of the measurement signal in the second direction and at the position value of the measurement signal in the third direction. Attached Figure Description

[0009] The above and other aspects, features and advantages of this disclosure will become more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

[0010] Figure 1 This is a diagram illustrating a semiconductor processing apparatus according to an exemplary embodiment of the present disclosure;

[0011] Figure 2 This is a diagram illustrating a light source system according to an exemplary embodiment of the present disclosure;

[0012] Figure 3 It is shown Figure 2 An enlarged view of area "A" shown;

[0013] Figure 4 This is a block diagram illustrating a semiconductor processing apparatus according to an exemplary embodiment of the present disclosure;

[0014] Figure 5 This is a flowchart illustrating the process of controlling the oscillation timing of a semiconductor processing apparatus according to an exemplary embodiment of the present disclosure;

[0015] Figure 6 This is a diagram illustrating the position values ​​in the first direction to the third direction according to an exemplary embodiment of this disclosure;

[0016] Figure 7 and Figure 8 This is a block diagram illustrating a semiconductor processing apparatus according to an exemplary embodiment of the present disclosure;

[0017] Figure 9 This is a diagram illustrating a compensation function included in a feedforward compensator according to an exemplary embodiment of the present disclosure;

[0018] Figure 10 This illustrates the provisions of this disclosure. Figure 9 A diagram illustrating the application of the compensation function in the example embodiment shown in the figure;

[0019] Figure 11 This illustrates the provisions of this disclosure. Figure 9 The diagram shows the energy dispersion of extreme ultraviolet light output from a light source generator including a compensation function, representing an example embodiment.

[0020] Figure 12 This is a diagram illustrating a compensation function included in a feedforward compensator according to an exemplary embodiment of the present disclosure;

[0021] Figure 13 This illustrates the provisions of this disclosure. Figure 9 A diagram illustrating the application of the compensation function in the example embodiment shown in the figure;

[0022] Figure 14 This is a diagram illustrating the energy dispersion of extreme ultraviolet light output from a light source generator including a compensation function according to an exemplary embodiment of the present disclosure;

[0023] Figure 15This is a block diagram illustrating a semiconductor processing apparatus according to an exemplary embodiment of the present disclosure;

[0024] Figure 16 This is a diagram illustrating the magnitude of the energy of extreme ultraviolet light according to an exemplary embodiment of the present disclosure; and

[0025] Figure 17 This is a diagram illustrating the calculation of oscillation time points according to an example embodiment of the present disclosure. Detailed Implementation

[0026] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings.

[0027] Figure 1 This is a diagram illustrating a semiconductor processing apparatus according to an example embodiment.

[0028] Reference Figure 1 The semiconductor processing apparatus 10 according to the example embodiment can be implemented as an apparatus for performing a photolithography process and may include an illumination unit 11, a mask stage 14, a projection optics system 16, a substrate stage 17, and a controller 19.

[0029] The illumination unit 11 may include a light source system 12 and an illumination optics system 13, and the light source system 12 may generate and output extreme ultraviolet light with high energy density in a wavelength band ranging from a few nanometers to tens of nanometers. In an example embodiment, the light source system 12 may generate and output extreme ultraviolet light with high energy density in a wavelength band of 13.5 nm. The light source system 12 may include a plasma-based light source or a synchrotron radiation source.

[0030] As an example, the light source system 12 can use plasma-output extreme ultraviolet light. The light source can operate in laser-generated plasma (LPP) mode, discharge-generated plasma (DPP) mode, or master oscillator power amplifier (MOPA) mode. In LPP mode, a high-output laser beam irradiates droplets formed from one of the materials such as tin, lithium, and xenon to generate plasma.

[0031] Plasma can be formed by irradiating droplets supplied by a droplet supplier with a laser beam. Therefore, the light source system 12 may include a condenser mirror and an illumination mirror for refocusing the extreme ultraviolet light formed by the plasma. The condenser mirror can function as a reflector and can be positioned close to the droplets to increase refocusing efficiency. The energy density of the extreme ultraviolet light output by the light source system 12 can be increased by using the illumination mirror and the condenser mirror.

[0032] The illumination optics system 13 may include a plurality of illumination mirrors. In the semiconductor processing apparatus 10 according to the example embodiment, the illumination optics system 13 may include two or more illumination mirrors. The illumination optics system 13 may transmit extreme ultraviolet light emitted by the light source system 12 to the mask stage 14. The extreme ultraviolet light emitted by the light source system 12 may be reflected by the illumination mirrors included in the illumination optics system 13 and may be incident on the mask 15 located on the mask stage 14.

[0033] In an example embodiment, mask 15 may be a reflective mask including non-reflective regions and / or intermediate reflective regions as well as reflective regions. Mask 15 may include a reflective multilayer film for reflecting extreme ultraviolet light on a substrate formed of a low thermal expansion coefficient material (LTEM) such as quartz, and an absorption layer pattern formed on the reflective multilayer film. The reflective multilayer film may have a structure in which layers formed of different materials are stacked. The absorption layer may be formed of TaN, TaNO, TaBO, Ni, Au, Ag, C, Te, Pt, Pd, Cr, etc. However, the material of the absorption layer is not limited to the above-mentioned materials, and the absorption layer portion may correspond to the aforementioned non-reflective regions and / or intermediate reflective regions.

[0034] The mask 15 can reflect the extreme ultraviolet light incident on it and can allow the extreme ultraviolet light to be incident on the projection optics system 16. The projection optics system 16 can be implemented as an imaging optics system disposed between the mask stage 14 and the substrate stage 17. For example, the extreme ultraviolet light passing through the illumination optics system 13 can be structured according to the pattern shape of the substrate in the mask 15, including a reflective multilayer film and an absorption layer, and can be incident on the projection optics system 16.

[0035] Extreme ultraviolet (EUV) light can be structured to include at least second-order diffraction light based on a pattern on mask 15. The structured EUV light can be incident on projection optics 16 while retaining information about the shape of the pattern included in mask 15, and can pass through projection optics 16 to illuminate substrate 18 situated on substrate stage 17, such that an image corresponding to the shape of the pattern included in mask 15 can be formed. For example, structured EUV light can illuminate a photoresist layer coated on substrate 18, and a specific pattern can be formed in the photoresist layer. However, in an example embodiment, the structured EUV light passing through projection optics 16 can be incident on a processing target other than substrate 18.

[0036] Extreme ultraviolet light reflected from mask 15 and passing through projection optics system 16 can be incident on the upper surface of substrate 18 at a specific slope. For example, projection optics system 16 can adjust the path of extreme ultraviolet light so that extreme ultraviolet light can be incident on the upper surface of substrate 18 at an incident angle of about 6 degrees.

[0037] Mask 15 may be located on mask stage 14, and substrate 18 may be located on substrate stage 17. For example, mask stage 14 and substrate stage 17 may be controlled by controller 19. In the initial state where mask 15 and substrate 18 are respectively located on mask stage 14 and substrate stage 17, and when the upper surfaces of mask 15 and substrate 18 are defined as the xy plane, mask stage 14 and substrate stage 17 may be moved by controller 19. In an example embodiment, controller 19 may cause mask stage 14 and substrate stage 17 to rotate relative to the Z-axis in the xy plane, or to rotate relative to an axis in the xy plane in the yz plane or xz plane. By moving mask stage 14 and / or substrate stage 17 as described above, mask 15 and / or substrate 18 may move or rotate along the X, Y, and Z axes in three-dimensional space.

[0038] The projection optical system 16 may include a plurality of projection mirrors. Each of the plurality of projection mirrors included in the projection optical system 16 may include a mirror body and a reflective layer attached to the surface of the mirror body. As described above, extreme ultraviolet light that passes through the illumination optical system 13 and is reflected by the mask 15 may be structured and incident on the projection optical system 16, and therefore, each of the plurality of projection mirrors may reflect the structured extreme ultraviolet light.

[0039] According to an example embodiment, the controller 19 can use the position of the droplet illuminated by the laser beam to control the oscillation time of the laser beam. For example, the oscillation time of the laser beam may correspond to the reference point. Figure 2 The laser source generator 140 described emits a laser beam to irradiate a droplet at a time that can be referred to as the laser beam emission time or the laser beam emission point. Therefore, the distance between the droplet and the central axis of the laser beam can be controlled at the point in time when the laser beam irradiates the droplet. In this case, the distance between the droplet and the central axis of the laser beam can be related to the emission direction of the droplet.

[0040] Therefore, the average energy of the generated extreme ultraviolet (EUV) light can be increased, and the energy dispersion of the EUV light can be reduced. This can shorten semiconductor processing time, thereby increasing productivity.

[0041] Figure 2 This is a diagram illustrating a light source system according to an example embodiment. Figure 3 It is shown Figure 2 An enlarged view of region "A" shown in the image.

[0042] Reference Figure 2 , Figure 2 The light source system 100 in the example embodiment shown can generate and output extreme ultraviolet light B. The light source system 100 can operate in an LPP manner to generate plasma P by irradiating a droplet DP with a laser beam L. However, its example embodiment is not limited to this.

[0043] The light source system 100 according to an example embodiment may include a chamber 110, a droplet feeder 120, a trap 130, a light source generator 140, a position sensor 150, a laser beam curtain generator 160, and a laser beam curtain sensor 170.

[0044] Chamber 110 can be filled with hydrogen (H2 gas) and oxygen (O2 gas) at ultra-low pressure. To prevent the extreme ultraviolet light B generated in chamber 110 from being absorbed by the gas in chamber 110, the interior portion of chamber 110 can be maintained at ultra-low pressure. The focal point F, which provides a path for emitting extreme ultraviolet light B, can be located on one side of chamber 110.

[0045] Chamber 110 may include a condenser lens 112. The condenser lens 112 can focus extreme ultraviolet light B to a focal point F. The condenser lens 112 may be a long-axis ellipsoidal mirror with a first focal point and a second focal point, the first focal point being located in the region where the droplet DP is irradiated by the laser beam L or in a region adjacent to that region, and the second focal point being located at the focal point F.

[0046] A light source generator 140, configured to emit a laser beam L, can be disposed on one surface of a condenser lens 112. An optical aperture can be disposed in the central portion of the condenser lens 112, thereby controlling the amount of illumination from the laser beam L emitted from the light source generator 140. A reflective layer can be formed on another surface of the condenser lens 112 to enhance the reflectivity of extreme ultraviolet light B, and the reflective layer may include multiple thin film layers in which molybdenum-silicon (Mo-Si) are stacked in a cross-stacking manner.

[0047] The droplet supplier 120 can supply droplets DP for generating extreme ultraviolet light B in the chamber 110. The droplet supplier 120 may include a droplet supply source 121 and a droplet discharge section 122.

[0048] The droplet supply source 121 can be used to apply a target material to form the droplet DP. The target material can be formed from materials such as tin, lithium, and xenon. The droplet DP can be formed by liquefying the target material, or the liquid material can contain solid particles of the target material.

[0049] By pressurizing the target material stored in the droplet supply source 121, the droplet DP can be discharged through the droplet discharge section 122. In this case, the droplet DP can be discharged along the first direction ( Figure 2 and Figure 3 Discharged along the X-axis direction, and specifically, the droplets DP can be discharged along... Figure 2 and Figure 3 The droplets DP emitted through the droplet emission section 122 can reach the internal region of the chamber 110 at a speed of approximately 20 m / s to 70 m / s and a time interval of approximately 20 μs. However, the speed and period of the droplet DP are not limited to these.

[0050] The light source generator 140 can emit a laser beam L that illuminates the droplet DP. The light source generator 140 can be a driving light source and can be positioned in a second direction ( Figure 2 and Figure 3 A laser beam L is emitted along the Z-axis direction. The laser beam L can be provided in the form of a pulse wave.

[0051] Refer to together Figure 2 and Figure 3 The laser beam L may include a first laser beam L1 and a second laser beam L2. For example, the first laser beam L1 may correspond to a pre-pulse, and the second laser beam L2 may correspond to a main pulse. Before the second laser beam L2 is absorbed and interacts with the droplet DP, the first laser beam L1 may pre-increase the surface area of ​​the droplet DP, thereby increasing the conversion efficiency. In this case, the conversion efficiency may be the ratio of the input power of the laser beam L emitted from the light source generator 140 to the output power of the emitted extreme ultraviolet light B.

[0052] As Figure 3 In the illustrated example embodiment, after the droplet DP is discharged from the droplet discharge section 122, the droplet DP can be irradiated with a first laser beam L1 and can expand into a pancake shape. Then, the droplet DP can be irradiated with a second laser beam L2, and the droplet DP irradiated with the second laser beam L2 explodes and can emit plasma P. The extreme ultraviolet light (not shown) omnidirectionally radiated from the plasma P can be collected by the condenser lens 112 as extreme ultraviolet light B.

[0053] Reference Figure 2 The collector 130 may be configured to face the droplet feeder 120 and to receive droplets DP discharged from the droplet feeder 120. The collector 130 may include a nozzle portion 131 and a vacuum source 132. The nozzle portion 131 may be configured to face the droplet discharge portion 122. The vacuum source 132 may provide a vacuum pressure below atmospheric pressure in the chamber 110, such that droplets DP can be drawn through the nozzle portion 131.

[0054] Position sensor 150 can be configured to be adjacent to chamber 110. Figure 2 In the example embodiment shown, the position sensor 150 may also be configured to be adjacent to the droplet feeder 120. The position sensor 150 may correspond to at least one of a four-element sensor and an image sensor. However, the position and / or type of the position sensor 150 are not limited thereto.

[0055] The position sensor 150 can be used to measure the position of a droplet DP illuminated by a laser beam L. Figure 1The controller 19 can use the output of the position sensor 150 to calculate a measurement signal indicating the position where the droplet DP is irradiated by the laser beam L. For example, the measurement signal may include information indicating the position where the laser beam L irradiates the droplet DP and where plasma light is generated. The measurement signal may include a first direction, a second direction, and a third direction within a specific time period. Figure 2 and Figure 3 The position value (in the Y-axis direction). In this case, the specific time period can be the period during which the droplet DP is emitted. In the embodiment, a single droplet is emitted during the specific time period.

[0056] The laser beam curtain generator 160 can generate a laser beam curtain LC. As... Figure 2 In the example embodiment shown, the laser beam curtain LC can be formed to extend into a plane defined by a second direction and a third direction. Figure 2 (The YZ plane in the image). A laser beam curtain LC can be formed between the droplet feeder 120 and the laser beam L. When the droplet DP passes through the laser beam curtain LC, the laser beam curtain LC can be reflected from the droplet DP.

[0057] The laser beam curtain sensor 170 can sense the reflected laser beam curtain LC. The time point at which the laser beam curtain sensor 170 senses the reflected laser beam curtain LC can correspond to a reference time point. According to an example embodiment, the time point at which the light source generator 140 emits the laser beam L can be calculated based on the reference time point.

[0058] According to an example embodiment, the oscillation timing can be controlled using the position values ​​of the first, second, and third directions of the measured signal during a specific time period. Therefore, the distance between the droplet and the laser beam in the first direction can be controlled at the point when the laser beam irradiates the droplet. This increases the average energy of the generated extreme ultraviolet light and reduces its energy dispersion. Consequently, semiconductor processing time can be shortened, and thus productivity can be increased.

[0059] Figure 4 This is a block diagram illustrating a semiconductor processing apparatus according to an example embodiment. Figure 5 This is a flowchart illustrating the process of controlling the oscillation timing of a semiconductor processing device according to an example embodiment. Figure 6 This is a diagram illustrating the position values ​​in the first direction to the third direction according to an example embodiment.

[0060] Semiconductor processing apparatus 200 may be an apparatus for performing photolithography processes and may include an illumination unit, a mask stage, a projection optics system, a substrate stage, and a controller 260. The illumination unit may include light source systems 210 to 250 and an illumination optics system. Light source systems 210 to 250 may generate and output extreme ultraviolet light. Specific example embodiments of the semiconductor processing apparatus 200 may be similar to those described in the reference document. Figure 1Example of the description.

[0061] First, refer to Figure 4 The light source systems 210 to 250 according to the example embodiments may include a chamber (not shown), a droplet supplier 210, a light source generator 220, and a position sensor 230. The light source systems 210 to 250 may also include a laser beam curtain generator 240 and a laser beam curtain sensor 250. Specific example embodiments of the light source systems 210 to 250 can be found with reference to... Figure 2 and Figure 3 The examples described are similar.

[0062] The droplet feeder 210 can form droplets and supply them to the interior region of the chamber along a first direction. The light source generator 220 can emit a laser beam along a second direction perpendicular to the first direction at an oscillation time point, thereby generating extreme ultraviolet light from the droplets. The position sensor 230 can be positioned adjacent to the chamber. However, the position of the position sensor 230 is not limited to this.

[0063] The laser beam generator 240 can emit a laser beam in a second direction. The laser beam sensor 250 can sense the laser beam reflected from the droplet as it passes through the laser beam. The controller 260 can determine the time point at which the laser beam sensor 250 senses the reflected laser beam as a reference time point, and can generate a reference signal that includes the reference time point within a specific time period.

[0064] The controller 260 can use a determination signal indicating the location where the droplet is expected to be irradiated by the laser beam to determine the oscillation time point. For example, the determination signal may include information indicating the location where the laser beam is expected to irradiate the droplet DP. Referring below... Figure 4 and Figure 5 Describe the processing of oscillation timing points by controller 260.

[0065] The controller 260 can receive a determination signal indicating the position where the droplet is expected to be irradiated by the laser beam (S100). The controller 260 can use the determination signal to calculate the oscillation time point at which the laser beam is emitted (S110). The oscillation time point can be calculated based on the distance between the droplet DP and the laser beam L in a first direction.

[0066] The droplet supplier 210 can generate droplets and supply droplets to the interior region of the chamber in a first direction (S120). Specifically, the droplet supplier 210 can discharge droplets via the discharge section by pressurizing the received target material, and the droplets can be discharged in the first direction.

[0067] The controller 260 can control the light source generator 220, and the controller 260 can control the light source generator 220 to emit a laser beam at a calculated oscillation time point. In other words, the light source generator 220 can emit a laser beam in a second direction perpendicular to the first direction at the oscillation time point (S130).

[0068] A laser beam can be directed onto a droplet to generate extreme ultraviolet (EUV) light (S140). Specifically, the droplet can be supplied in a first direction, and a laser beam emitted in a second direction can be directed onto the droplet to generate plasma. EUV light radiated omnidirectionally from the plasma can be collected and output. The EUV light generated in the light source systems 210 to 250 can pass through an illumination optics system, a mask stage, and a projection optics system, and can be directed onto a substrate to perform semiconductor processing. In this case, according to an example embodiment, the semiconductor processing can be a process using EUV light, and can be, for example, a photolithography process.

[0069] After irradiating the droplet with a laser beam and emitting extreme ultraviolet light, it can be determined whether the semiconductor processing using extreme ultraviolet light has terminated (S150). If it is determined in operation S150 that the semiconductor processing using extreme ultraviolet light has terminated, operations S100 to S140 do not need to be repeated. If it is determined in operation S150 that the semiconductor processing using extreme ultraviolet light has not terminated, the oscillation time point can be modified (S160 to S190), and the process of generating extreme ultraviolet light at the modified oscillation time point by irradiating the droplet with a laser beam can be performed (S120 to S140).

[0070] The controller 260 can calculate a measurement signal and an error signal (S160). The controller 260 can use the output of the position sensor 230 to calculate a measurement signal indicating the position of the droplet irradiated by the laser beam. The controller 260 can calculate an error signal as the difference between the determination signal and the measurement signal. For example, the error signal may include information representing the difference between the position indicated by the determination signal and the position indicated by the measurement signal.

[0071] Each of the determination signal, measurement signal, and error signal may include a position value in a first direction, a position value in a second direction, and a position value in a third direction perpendicular to both the first and second directions during a specific time period. The specific time period may correspond to the period during which the droplet is discharged. The position values ​​of the determination signal, measurement signal, and error signal in the first direction to the third direction will be described below.

[0072] Reference Figure 6 The first direction may correspond to the direction of travel of the droplet DP emitted from the droplet supplier 210. For example, the first direction may be... Figure 6 The -X axis direction. The second direction may correspond to the direction of travel of the laser beam L emitted from the light source generator 220, and the second direction may be... Figure 6 The Z-axis direction. Specifically, the laser beam L can be emitted linearly, and the optical axis OA of the laser beam L can coincide with the Z-axis. The third direction can be... Figure 6 The Y-axis direction in the diagram.

[0073] Figure 6 The origin O in the diagram can be the point where the X-axis and Z-axis intersect. According to the example embodiment, Figure 6 The origin O in the diagram can be the intersection point where the direction of droplet DP emission intersects the direction of laser beam emission. Specifically, refer to... Figure 2 The origin O can coincide with the first focal point of the condenser lens 112. When the center of the laser beam L is the origin O, the diameter D of the laser beam L can be minimized.

[0074] The diameter D of the laser beam L can be larger than the size of the droplet DP. Therefore, the droplet DP can be irradiated with the laser beam L at points defined by different coordinates within the laser beam L.

[0075] The position value from the first direction to the third direction can be Figure 6 The relative distance from the origin O. According to the example embodiment, Figure 6 The location of the droplet DP illuminated by the laser beam L can be indicated. The location of the droplet DP illuminated by the laser beam L can be a relative distance from the origin O. The location of the droplet DP illuminated by the laser beam L can be defined by coordinates. In an embodiment, the location represented by the determined signal may initially correspond to a reference point. Figure 2 The described droplet supplier 120 sequentially generates multiple droplets, and the origin O of the first droplet supplied is determined. For laser irradiation of the next droplet, the position represented by the determined signal can be updated using the difference between the position represented by the measurement signal of the first droplet and the position of the determined signal (e.g., origin O). For example, it can control the reference... Figure 2 The described laser source generator 140 causes the laser to be emitted toward a newer position. For example, the direction of laser emission toward the current droplet can be determined using a measurement signal from the previous droplet.

[0076] The coordinates of the position of the droplet DP illuminated by the laser beam L may include a position value Xm in a first direction, a position value Zm in a second direction, and a position value Ym in a third direction. That is, the measurement signal may include the position value Xm in the first direction, the position value Zm in the second direction, and the position value Ym in the third direction during a specific time period. The position values ​​Xm, Zm, and Ym in the first direction and the third direction can be positive values, but the example embodiments are not limited thereto.

[0077] The signal can be determined to indicate the position where the droplet DP is expected to be irradiated by the laser beam L within a specific time period, and this position can be defined by coordinates. Although Figure 6Not shown, but the coordinates for determining the position of the droplet DP irradiated by the laser beam L may include a position value Xs in a first direction, a position value Zs in a second direction, and a position value Ys in a third direction. That is, the determining signal may include the position value Xs in the first direction, the position value Zs in the second direction, and the position value Ys in a third direction during a specific time period.

[0078] The error signal can be the difference between the deterministic signal and the measured signal. Although Figure 6 Not shown, but the error signal may include a position value Xe in a first direction, a position value Ze in a second direction, and a position value Ye in a third direction during a specific time period. During the specific time period, the position value Xe of the error signal in the first direction may be the error between the position value Xs of the determined signal in the first direction and the position value Xm of the measured signal in the first direction. The position value Ze of the error signal in the second direction may be the error between the position value Zs of the determined signal in the second direction and the position value Zm of the measured signal in the second direction. The position value Ye of the error signal in the third direction may be the error between the position value Ys of the determined signal in the third direction and the position value Ym of the measured signal in the third direction.

[0079] The controller 260 can use at least one of the position value Ze of the error signal in the second direction and the position value Ye of the error signal in the third direction to calculate a position compensation value in the first direction (S170). The position compensation value in the first direction can compensate for the position value Xs of the determination signal in the first direction. In other words, the position value Xs in the first direction can be changed using at least one of the position value Ze of the error signal in the second direction and the position value Ye of the error signal in the third direction.

[0080] The controller 260 can use the position value Xe of the error signal in the first direction and the position compensation value in the first direction to calculate the standby time (S180). Specifically, the standby time can be calculated using the position value Xs of the determination signal in the first direction, the position value Xm of the measurement signal in the first direction, and the position compensation value in the first direction. Figure 4 The light source generator 220 can emit laser light during a standby time after detecting that a droplet has entered a laser beam curtain formed on a plane defined by the Y and Z axes. For example, the light source generator 220 can emit laser light in pulses at a specific period.

[0081] The controller 260 can determine the time point after the standby time starting from the reference time point as the oscillation time point (S190), and can perform the process of irradiating the droplet with a laser beam and generating extreme ultraviolet light at the determined oscillation time point (S120 to S140).

[0082] Figure 7 and Figure 8This is a block diagram illustrating a semiconductor processing apparatus according to an example embodiment.

[0083] Semiconductor processing apparatus 300 and semiconductor processing apparatus 400 may include a light source generator 310, a light source generator 410, a position sensor 320 and a position sensor 420, and a controller 330 and a controller 430. Specific example embodiments of semiconductor processing apparatus 300 and 400 may be similar to those described above. Figures 1 to 6 Example of the description.

[0084] Controllers 330 and 430 can receive a determination signal indicating the location where the droplet is expected to be irradiated by the laser beam. The determination signal may include position values ​​Xs, Zs, and Ys respectively in a first direction to a third direction within a specific time period.

[0085] Controllers 330 and 430 can generate a reference signal tref, which can be a reference to the oscillation time point tfr. Specifically, the reference... Figure 2 Controllers 330 and 430 can determine the time point at which the laser beam curtain sensor 170 senses the reflected laser beam curtain LC as a reference time point. The reference signal tref may include a reference time point within a specific time period.

[0086] Controllers 330 and 430 can use the output signals of position sensors 320 and 420 to calculate measurement signals indicating the position of the droplet irradiated by the laser beam. The measurement signals may include position values ​​Xm, Zm, and Ym in a first direction to a third direction during a specific time period.

[0087] Controllers 330 and 430 can use the deterministic signal and the measurement signal to calculate the error signal. For example, the error signal may correspond to the difference between the deterministic signal and the measurement signal. The error signal may include position values ​​Xe, Ze, and Ye in a first direction to a third direction during a specific time period.

[0088] Each of the determination signal, reference signal, measurement signal, and error signal may correspond to a discrete-time signal having a position value in a first direction to a third direction at intervals of specific time periods. In this case, the specific time period may coincide with the time period for discharging the droplets. For example, the droplet feeder 120 may be controlled to sequentially discharge each of a plurality of droplets into the space defined by the chamber 110 within a specific time period. However, exemplary embodiments thereof are not limited thereto.

[0089] According to the example embodiments, semiconductor processing device 300 and semiconductor processing device 400 may include feedback controller 332 and feedback controller 432 that generate feedback signal tfb, and feedforward compensator 334 and feedforward compensator 434 that generate feedforward signal Xff.

[0090] According to an example embodiment, feedback controllers 332 and 432 can receive a feedforward signal Xff during a specific time period, a position value Xs of a determined signal in a first direction, and a position value Xm of a measured signal in the first direction, and can output a feedback signal tfb. In other words, feedback controllers 332 and 432 can generate the feedback signal tfb by performing feedback control on a first signal, wherein the first signal is obtained by adding the feedforward signal Xff to the difference between the position value Xs of the determined signal in the first direction and the position value Xm of the measured signal in the first direction during a specific time period. For example, feedback controllers 332 and 432 can receive the first signal and generate the feedback signal tfb based on the first signal and the droplet's travel speed. In this case, the feedback signal tfb can be a signal indicating the standby time during a specific time period.

[0091] According to the example embodiment, feedforward compensators 334 and 434 can receive the position value Ze of the error signal in the second direction or the position value Ye of the error signal in the third direction, and can output a feedforward signal Xff. In this case, the feedforward signal Xff can be a signal indicating a position compensation value in the first direction for compensating the position value Xs of the determined signal in the first direction during a specific time period.

[0092] First, refer to Figure 7 The feedforward compensator 334 can perform feedforward compensation on the position value Ye of the error signal in the third direction, and can generate and output a feedforward signal Xff. The feedforward signal Xff can be a value that changes the position value Xs of the determined signal in the first direction using the position value Ye of the error signal in the third direction. For example, the feedforward signal Xff can be a value generated based on the position value Ye of the error signal in the third direction, and can be added to the position value Xs of the determined signal to generate a new position value for the determined signal. The position value Xs and the new position value can be as follows: Figure 6 The x-coordinate value is shown as the distance from the origin O. Therefore, the position of the droplet in the first direction irradiated by the laser beam to be used in the next specific time period can be changed.

[0093] Reference Figure 8 The feedforward compensator 434 can perform feedforward compensation on the position value Ze of the error signal in the second direction, and can generate and output a feedforward signal Xff. The feedforward signal Xff can be a value that changes the position value Xs of the determined signal in the first direction using the position value Ze of the error signal in the second direction. For example, the feedforward signal Xff can be a value generated based on the position value Ze of the error signal in the second direction, and can be added to the position value Xs of the determined signal to generate a new position value for the determined signal. The position value Xs and the new position value can be as follows: Figure 6The x-coordinate value is shown as the distance from the origin O. Therefore, the position of the droplet in the first direction irradiated by the laser beam to be used for the next specified time period can be changed.

[0094] Reference Figure 7 and Figure 8 Controllers 330 and 430 can determine the oscillation time point tfr by adding the feedback signal tfb to the reference signal tref. In other words, the oscillation time point tfr can be a time point after the standby time starting from the reference time point.

[0095] Controllers 330 and 430 can control light source generators 310 and 410 to emit a laser beam at an oscillation time point tfr. Controllers 330 and 430 can repeat the previously described processes, such as calculating a measurement signal using the outputs of position sensors 320 and 420 when the droplet is irradiated with a laser beam.

[0096] Figure 9 This is a diagram illustrating a compensation function included in a feedforward compensator according to an example embodiment.

[0097] The semiconductor processing apparatus may include a droplet feeder, a light source generator, a position sensor, and a controller. The controller may include a feedback controller and a feedforward compensator. Specific example embodiments of the semiconductor processing apparatus may be similar to those described in the references. Figures 1 to 7 Examples of the description. In an embodiment, each of the feedback controller and the feedforward compensator may correspond to a software functional module running in the controller. In an embodiment, each of the feedback controller and the feedforward compensator may correspond to a functional circuit block that performs the operations described below. In an embodiment, each of the feedback controller and the feedforward compensator may be a hybrid functional block, wherein a portion of the operations performed by each of the feedback controller and the feedforward compensator are implemented using software functional blocks, while other portions are implemented as functional circuit blocks.

[0098] According to an example embodiment, the feedforward compensator may include a compensation function G. Figure 9 The compensation function G in the example embodiments shown may correspond to a linear function. That is, the feedforward compensator may be a linear system. However, the example embodiments are not limited to this, and the feedforward compensator may correspond to a nonlinear system, a static system, or a dynamic system.

[0099] Figure 9The extreme ultraviolet (EUV) light energy dispersion can indicate the position values ​​of the measurement signal in the X-axis direction and the position values ​​in the Y-axis direction. The EUV light energy dispersion can be shown in order of higher energies, in the sequence of first region E1, second region E2, third region E3, and fourth region E4. The EUV light energy dispersion can include multiple energy data points {Xi, Yi, Ei}, where i can be a positive integer representing each droplet supplied by the droplet supplier 120.

[0100] Figure 9 The compensation function G in the illustrated example embodiment can be calculated based on the energy dispersion of extreme ultraviolet light from a semiconductor processing device excluding a feedforward compensator. In other words, the semiconductor processing device can determine the oscillation time point by only performing feedback control on the position value of the error signal in the first direction, and can perform feedforward compensation on the position value of the error signal in the third direction without performing feedforward compensation.

[0101] exist Figure 9 In the example embodiment shown, multiple energy data points {Xi, Yi, Ei} can be divided into N groups, where N can be 20. For each of the N groups, multiple energy group data points {GXj, GYj} can be calculated, where j can be a positive integer corresponding to the order of the N groups. GXj can be calculated using Equation 1.

[0102] [Equation 1]

[0103]

[0104] The interval between the maximum and minimum values ​​of Xi in multiple energy data points can be divided into N X parts with equal intervals on the X-axis. For each of the N X parts, GXj can correspond to the median value of each of the N X parts. Gyj can be calculated using equations 2 to 4.

[0105] [Equation 2]

[0106]

[0107] [Equation 3]

[0108]

[0109] [Equation 4]

[0110] GYj = Yi | (i = Sj)

[0111] For each of the N X parts, Gyj can correspond to Yi, and Yi corresponds to the Xi with the maximum energy among the {Xi} included in each of the N X parts.

[0112] As Figure 9In the example embodiment shown, the compensation function G can be a primary function of Y relative to X, calculated by linearly fitting {GXj, Gyj}. In other words, the compensation function G can be a linear function that fits the position values ​​in the Y-axis direction, where the extreme ultraviolet light has the maximum energy relative to the position values ​​in the X-axis direction.

[0113] Figure 10 It shows the basis Figure 9 The diagram illustrates the application of the compensation function in the example embodiment shown.

[0114] The semiconductor processing apparatus may include a droplet feeder, a light source generator, a position sensor, and a controller. The controller may include a feedback controller and a feedforward compensator. The feedforward compensator may include a compensation function G. Specific example embodiments of the semiconductor processing apparatus may be similar to those described in the reference section. Figures 1 to 7 Example of the description.

[0115] Figure 10 Can represent and Figure 9 The relationship between the maximum energy at the position value in the Y-axis and the position value in the X-axis is shown by the corresponding compensation function G, and the compensation function G can be a linear function of the position value in the Y-axis direction, where the extreme ultraviolet light has the maximum energy relative to the position value of the measurement function in the X-axis direction.

[0116] Figure 10 The position value Xs of the determined signal in the X-axis direction and the position value Ys in the Y-axis direction can be shown together. Each of the position values ​​Xs and Ys of the determined signal in the X-axis direction can be positive and / or negative. Alternatively, at least one of the position values ​​Xs and Ys of the determined signal in the X-axis direction can be 0.

[0117] During a first specific time period, the laser beam can irradiate the first droplet at the first position M1. The measurement signal of the first droplet may include a position value Xm1 in the X-axis direction and a position value Ym1 in the Y-axis direction. The position value Xm1 of the measurement signal of the first droplet in the X-axis direction may be the same as the position value Xs of the determination signal in the X-axis direction.

[0118] The position value of the error signal of the first droplet in the Y-axis direction can be the difference between Ys and Ym1. In the position value Ym1 of the measurement signal of the first droplet in the Y-axis direction, the position value where the extreme ultraviolet light has the maximum energy in the X-axis direction can be Xm1'. The feedforward compensator can calculate and determine the difference between the signal Xs and Xm1' in the X-axis direction as the position compensation value in the first direction.

[0119] During a second specific time period, a laser beam can be used to illuminate the second droplet at the second position M2. The measurement signal of the second droplet may include a position value Xm2 in the X-axis direction and a position value Ym2 in the Y-axis direction. The position value Ym2 of the measurement signal of the second droplet in the Y-axis direction may be the same as the position value Ys of the determination signal in the Y-axis direction.

[0120] The position value of the error signal of the second droplet in the Y-axis direction can be 0. In other words, the extreme ultraviolet light has maximum energy at the position value Ym2 of the measurement signal of the second droplet in the Y-axis direction. That is, the feedforward compensator can calculate the position compensation value in the first direction as 0.

[0121] During the third specific time period, the laser beam can irradiate the third droplet at the third position M3. The measurement signal of the third droplet can include the position value Xm3 in the X-axis direction and the position value Ym3 in the Y-axis direction.

[0122] The position value of the error signal of the third droplet in the Y-axis direction can be the difference between Ys and Ym3. Within the position value Ym3 of the measurement signal of the third droplet in the Y-axis direction, the position value where the extreme ultraviolet light has the maximum energy in the X-axis direction can be Xm3'. The feedforward compensator can calculate and determine the difference between the position values ​​Xs and Xm3' of the signal in the X-axis direction, as the position compensation value in the first direction.

[0123] Figure 11 It shows the basis Figure 9 The diagram shows the energy dispersion of extreme ultraviolet light output from a light source generator including a compensation function, representing an example embodiment.

[0124] Semiconductor processing equipment may include a light source generator and a controller. Specific example embodiments of the semiconductor processing equipment may be similar to those described in the reference section. Figures 1 to 6 The described embodiments.

[0125] According to an example embodiment, the controller can use the position value of the error signal in a third direction to calculate a position compensation value in a first direction. The controller can use the position value of the determination signal in the first direction and the position compensation value in the first direction to determine the oscillation time point. Specific example embodiments may be similar to those described above. Figure 7 , Figure 9 and Figure 10 Example of the description.

[0126] Figure 11 This could be a diagram illustrating the energy dispersion of extreme ultraviolet light according to an example embodiment. The diagram will be presented according to the example embodiment and comparative examples, and with reference to... Figure 9 Together, we describe the energy dispersion of extreme ultraviolet light. Figure 9This is a diagram showing the energy dispersion of extreme ultraviolet light according to a comparative example, and the energy dispersion of extreme ultraviolet light corresponding to the position compensation value in the first direction calculated without using an error signal in the position value in the third direction.

[0127] Figure 9 and Figure 11 The energy dispersion of extreme ultraviolet light can represent the position values ​​of the measured signal in the X-axis direction and the Y-axis direction. The energy of the extreme ultraviolet light can be shown in order of higher energy, in the sequence of first region E1, second region E2, third region E3, and fourth region E4.

[0128] The energy dispersion of the extreme ultraviolet light according to the exemplary embodiment is lower than that of the extreme ultraviolet light according to the comparative example. The average energy of the extreme ultraviolet light according to the exemplary embodiment is higher than that of the extreme ultraviolet light according to the comparative example. Therefore, semiconductor processing time can be shortened and productivity can be improved.

[0129] Figure 12 This is a diagram illustrating a compensation function included in a feedforward compensator according to an example embodiment.

[0130] The semiconductor processing apparatus may include a droplet feeder, a light source generator, a position sensor, and a controller. The controller may include a feedback controller and a feedforward compensator. Specific example embodiments of the semiconductor processing apparatus may be similar to those described in the references. Figures 1 to 6 and Figure 8 Example of the description.

[0131] According to an example embodiment, the feedforward compensator may include a compensation function G. Figure 12 The compensation function G in the example embodiments shown may correspond to a linear function. That is, the feedforward compensator may be a linear system. However, the example embodiments are not limited to this, and the feedforward compensator may correspond to a nonlinear system, a static system, or a dynamic system.

[0132] Figure 12 The energy dispersion of the extreme ultraviolet light relative to the measurement signal in the X-axis and Z-axis directions can be indicated. The energy dispersion of the extreme ultraviolet light can be shown in order of higher energies, in the sequence of first region E1, second region E2, third region E3, and fourth region E4. The energy dispersion of the extreme ultraviolet light can include multiple energy data points {Xi, Zi, Ei}, where i can be a positive integer representing each droplet supplied by the droplet supplier 120.

[0133] Figure 12The compensation function G in the illustrated example embodiment can be calculated based on the energy dispersion of extreme ultraviolet light from a semiconductor processing device excluding a feedforward compensator. In other words, the semiconductor processing device can determine the oscillation time point by only performing feedback control on the position value of the error signal in the first direction, and can perform feedforward compensation on the position value of the error signal in the second direction without performing feedforward compensation.

[0134] exist Figure 12 In the example embodiment shown, multiple energy data points {Xi, Zi, Ei} can be divided into N groups, where N can be 20. For each of the N groups, multiple energy group data points {GXj, GZj} can be calculated, where j can be a positive integer corresponding to the order of the N groups. GXj can be determined by referring to... Figure 9 Equation 1 described is calculated. GZj can be obtained by referring to... Figure 9 Calculate Equations 2, 3, and 5 as described.

[0135] [Equation 5]

[0136] GZj=Zi|(i=Sj)

[0137] For each of the N X parts, GZj can correspond to Zi, and Zi corresponds to the Xi with the maximum energy among the {Xi} included in each of the N X parts.

[0138] As Figure 12 In the example embodiment shown, the compensation function G can be a basis function of Z relative to X, calculated by linearly fitting {GXj, GZj}. In other words, the compensation function G can be a linear function that fits the position value of the extreme ultraviolet light in the Z-axis direction with the maximum energy to the position value in the X-axis direction.

[0139] Figure 13 It shows the basis Figure 9 The diagram illustrates the application of the compensation function in the example embodiment shown.

[0140] The semiconductor processing apparatus may include a droplet feeder, a light source generator, a position sensor, and a controller. The controller may include a feedback controller and a feedforward compensator. The feedforward compensator may include a compensation function G. Specific example embodiments of the semiconductor processing apparatus may be similar to those described in the reference section. Figures 1 to 6 and Figure 8 Example of the description.

[0141] Figure 13 Instructions as Figure 12 The compensation function G represents the relationship between the maximum energy at the position value on the X-axis and the position value on the X-axis. In an embodiment, the compensation function G can be a linear function of the position value in the Z-axis direction, where the extreme ultraviolet light has the maximum energy relative to the position value of the measurement function in the X-axis direction.

[0142] Figure 13 The position values ​​Xs and Zs of the determined signal in the X-axis direction and Z-axis direction can be shown together. The position values ​​Xs and Zs of the determined signal in the X-axis direction and Z-axis direction can be positive and / or negative, respectively. Alternatively, at least one of the position values ​​Xs and Zs of the determined signal in the X-axis direction and Z-axis direction can be 0.

[0143] During a first specific time period, the laser beam can irradiate the first droplet at the first position M1. The measurement signal of the first droplet may include the position value Xm1 in the X-axis direction and the position value Zm1 in the Z-axis direction.

[0144] The Z-axis position value of the error signal of the first droplet can be the difference between Zs and Zm1. Regarding the Z-axis position value Zm1 of the measurement signal of the first droplet, the position value where the extreme ultraviolet light has maximum energy in the X-axis direction can be Xm1'. The feedforward compensator can calculate and determine the difference between the X-axis position values ​​Xs and Xm1' of the signal, as the position compensation value in the first direction.

[0145] During a second specific time period, a laser beam can be used to irradiate the second droplet at the second position M2. The measurement signal of the second droplet may include a position value Xm2 in the X-axis direction and a position value Zm2 in the Z-axis direction. The position value Zm2 of the measurement signal of the second droplet in the Z-axis direction may be the same as the position value Zs of the determination signal in the Z-axis direction.

[0146] The position value of the error signal of the second droplet in the Z-axis direction can be 0. In other words, since the maximum energy of the extreme ultraviolet light is formed in the position value Zm2 of the measurement signal of the second droplet in the Z-axis direction, it is not necessary to change the oscillation point in a timely manner. That is to say, the feedforward compensator can calculate the position compensation value in the first direction as 0.

[0147] During the third specific time period, a laser beam can be used to irradiate the third droplet at the third position M3. The measurement signal of the third droplet may include a position value Xm3 in the X-axis direction and a position value Zm3 in the Z-axis direction. The position value Xm3 of the measurement signal of the third droplet in the X-axis direction may be the same as the position value Xs of the determination signal in the X-axis direction.

[0148] The position value of the error signal of the third droplet in the Z-axis direction can be the difference between Zs and Zm3. Regarding the position value Zm3 of the measurement signal of the third droplet in the Z-axis direction, the position value of the extreme ultraviolet light in the X-axis direction with maximum energy can be Xm3'. The feedforward compensator can calculate and determine the difference between the position values ​​Xs and Xm3' of the signal in the X-axis direction as the position compensation value in the first direction.

[0149] Figure 14This is a diagram illustrating the energy dispersion of extreme ultraviolet light output by a light source generator including compensation functions according to an example embodiment.

[0150] Semiconductor processing equipment may include a light source generator and a controller. Specific example embodiments of the semiconductor processing equipment may be similar to those described in the reference section. Figures 1 to 6 The described embodiments.

[0151] According to an example embodiment, the controller can use the position value of the error signal in the second direction to calculate the position compensation value in the first direction. The controller can use the position value of the determination signal in the first direction and the position compensation value in the first direction to determine the oscillation time point. Specific example embodiments may be similar to those described above. Figure 8 , Figure 12 and Figure 13 Example of the description.

[0152] Figure 14 This could be a diagram illustrating the energy dispersion of extreme ultraviolet light according to an example embodiment. The diagram will be presented according to the example embodiment and comparative examples, and with reference to... Figure 12 Together, we describe the energy dispersion of extreme ultraviolet light. Figure 12 This is a diagram showing the energy dispersion of extreme ultraviolet light according to a comparative example, and the energy dispersion of extreme ultraviolet light corresponding to the position compensation value in the first direction calculated without using an error signal in the second direction.

[0153] Figure 12 and Figure 14 It can indicate the energy dispersion of extreme ultraviolet light for the position values ​​of the measured signal in the X-axis direction and the Z-axis direction. The energy of the extreme ultraviolet light can be shown in the order of first region E1, second region E2, third region E3 and fourth region E4, with higher energies.

[0154] The energy dispersion of the extreme ultraviolet light according to the exemplary embodiment is lower than that of the extreme ultraviolet light according to the comparative example. The average energy of the extreme ultraviolet light according to the exemplary embodiment is higher than that of the extreme ultraviolet light according to the comparative example. Therefore, semiconductor processing time can be shortened and productivity can be improved.

[0155] Figure 15 This is a block diagram illustrating a semiconductor processing apparatus according to an example embodiment.

[0156] Semiconductor processing apparatus 500 may include a light source generator 510, a position sensor 520, and a controller 530. The controller 530 may receive a determination signal, use the output signal of the position sensor 520 to calculate a measurement signal indicating the position of the droplet irradiated by the laser beam, and calculate an error signal. Specific example embodiments may be similar to those described above. Figures 1 to 6 Example of the description.

[0157] According to an example embodiment, the semiconductor processing device 500 may include a feedback controller 532 that generates a feedback signal tfb and a feedforward compensator 534 that generates a feedforward signal Xff.

[0158] The feedback controller 532 can receive a feedforward signal Xff for a specific time period, a position value Xs of a determined signal in a first direction, and a position value Xm of a measured signal in the first direction, and can output a feedback signal tfb. In other words, the feedback controller 532 can generate the feedback signal tfb by performing feedback control on the signal, wherein the signal is obtained by adding the feedforward signal Xff and the difference between the position value Xs of the determined signal in the first direction and the position value Xm of the measured signal in the first direction within the specific time period. In this case, the feedback signal tfb can be a signal indicating the standby time within the specific time period.

[0159] The feedforward compensator 534 of the semiconductor processing device 500 can be connected with Figure 7 and Figure 8 The feedforward compensators 334 and 434 of the semiconductor processing devices 300 and 400 shown differ in that the feedforward compensator 534 can generate a feedforward signal Xff by using the position value Ze in the second direction and the position value Ye in the third direction using an error signal. In this case, the feedforward signal Xff can be a signal representing the position compensation value in the first direction during a specific time period.

[0160] Reference Figure 15 The feedforward compensator 534 can perform feedforward compensation on the position value Ze of the error signal in the second direction and the position value Ye in the third direction, and can generate and output a feedforward signal Xff. The feedforward signal Xff can be used to change the value of the position value Xs of the determination signal in the first direction by using the position value Ze of the error signal in the second direction and the position value Ye in the third direction. Therefore, the position of the droplet irradiated by the laser beam in the first direction can be changed.

[0161] and Figure 7 and Figure 8 compared to, Figure 15 The feedforward compensator 534 in the middle can use the position value Ze in the second direction and the position value Ye in the third direction of the error signal to change the position value Xs of the determination signal in the first direction, thereby precisely controlling the position of the droplet irradiated by the laser beam in the first direction. Therefore, the extreme ultraviolet light can be rapidly controlled to have maximum energy, and the energy dispersion of the extreme ultraviolet light can be rapidly reduced.

[0162] Figure 15The feedforward compensator 534 may include a compensation function, and for the position values ​​in the X-axis direction, Y-axis direction, and Z-axis direction with the maximum energy of extreme ultraviolet light, the compensation function may be a multivariable function or a multiple-input single-output system (MISO system).

[0163] The controller 530 can determine the oscillation time point tfr as the signal obtained by adding the feedback signal tfb to the reference signal tref. In other words, the oscillation time point tfr can be a time point after the standby time starting from the reference time point.

[0164] The controller 530 can control the light source generator 510 to emit a laser beam at the oscillation time point tfr. The controller 530 can repeat the above process, such as using the output of the position sensor 520 to calculate a measurement signal when the droplet is irradiated with the laser beam.

[0165] Figure 16 This is a diagram illustrating the magnitude of the energy of extreme ultraviolet light according to an example embodiment.

[0166] The semiconductor processing apparatus according to an example embodiment can calculate a position compensation value in a first direction using at least one of the position value of the error signal in a second direction and the position value of the error signal in a third direction. The semiconductor processing apparatus can determine the oscillation time point using the position value of the determined signal in the first direction, the position value of the measured signal in the first direction, and the position compensation value in the first direction. Therefore, the position value in the first direction of irradiating the droplet with a laser beam can be controlled.

[0167] The semiconductor processing apparatus according to the exemplary embodiments and comparative examples of this disclosure can use the position value of the error signal in a first direction to calculate the oscillation time point, and may not reflect the position value of the error signal in a second direction and the position value of the error signal in a third direction to the oscillation time point. In other words, the semiconductor processing apparatus may not calculate the position compensation value in the first direction.

[0168] Figure 16 This can represent the magnitude of extreme ultraviolet (EUV) energy over time. The unit of time can be seconds (s), and the unit of energy of EUV light can be millijoules (mJ).

[0169] The maximum energy of the extreme ultraviolet (EUV) light according to the exemplary embodiment is greater than the maximum energy of the EUV light according to the comparative example. The difference between the maximum and minimum energies of the EUV light according to the exemplary embodiment is less than the difference between the maximum and minimum energies of the EUV light according to the comparative example. The average energy of the EUV light according to the exemplary embodiment is greater than the average energy of the EUV light according to the comparative example. In other words, the energy dispersion of the EUV light according to the exemplary embodiment is less than the energy dispersion of the EUV light according to the comparative example. Therefore, semiconductor processing time can be shortened, thereby improving productivity.

[0170] Figure 17 This is a diagram illustrating the calculation of oscillation time points according to an example embodiment.

[0171] According to an example embodiment, a semiconductor processing apparatus may include a chamber, a droplet feeder, a light source generator, a position sensor, a laser beam curtain generator, and a laser beam curtain sensor, serving as an apparatus for performing photolithography. Specific example embodiments of the semiconductor processing apparatus may be similar to those described above. Figures 1 to 16 The described embodiments.

[0172] According to an example embodiment, the laser beam curtain generator can be along the second direction ( Figure 17 A laser beam curtain is emitted along the Z-axis direction. Unlike a light source generator that is configured to emit a laser beam at oscillation points, a laser beam curtain generator can continuously emit a laser beam curtain while performing semiconductor processing.

[0173] Reference Figure 2 The droplet feeder can form droplets, and can do so in the first direction ( Figure 17 The droplet is supplied to the interior region of the chamber along the X-axis direction. In other words, the droplet can move in the first direction. The laser beam curtain sensor can sense the laser beam curtain reflected from the droplet as it passes through it.

[0174] The point at which the droplet crosses the laser beam can be predetermined. During semiconductor processing, the point at which the droplet crosses the laser beam can be controlled to be constant. Figure 17 In the example embodiment shown, the point where the droplet passes through the laser beam can have a position value Xlc in a first direction.

[0175] For the position value of a droplet passing through the laser beam curtain in the first direction, the controller can determine the time point at which the laser beam curtain sensor senses the laser beam curtain reflected from the droplet as the reference time point tref.

[0176] The controller can calculate the time interval required for the droplet to reach the position value Xs of the determination signal in the first direction from the point where it passes through the laser beam, as the standby time tstb. The controller can calculate the waiting time tstb using the relationship between the distance between the position value Xlc of the droplet in the first direction and the position value Xs of the determination signal in the first direction and the droplet's moving speed.

[0177] The controller can calculate the time point after the standby time tstb starting from the reference time point tref as the oscillation time point tfr. The light source generator can emit a laser beam along a second direction at the oscillation time point tfr, so that the laser beam can irradiate the droplet and form extreme ultraviolet light.

[0178] The process of calculating the oscillation time point tfr can be repeated within a specific time period. For example, the specific time period could be the period during which droplets are emitted, but its example embodiments are not limited to this.

[0179] According to the above example embodiment, by controlling the oscillation time of the laser beam emitted by the light source generator in the light source system included in the semiconductor processing device, the position value of the droplet irradiated by the laser beam in a first direction can be controlled. Therefore, the average energy of the extreme ultraviolet light generated from the droplet can be increased, and the energy dispersion of the extreme ultraviolet light can be reduced.

[0180] Although exemplary embodiments have been described and illustrated above, it will be apparent to those skilled in the art that modifications and variations may be made without departing from the scope of this disclosure as defined by the appended claims.

Claims

1. A semiconductor processing apparatus comprising: a droplet supplier configured to form a first droplet and supply the first droplet to a chamber along a first direction for a first specific period; a light source generator configured to emit a laser beam along a second direction perpendicular to the first direction at a first emission time point such that extreme ultraviolet light is generated from the first droplet; a position sensor disposed adjacent to the chamber; and a controller configured to: receive a determination signal including first information representing a first position at which the laser beam is intended to irradiate the first droplet; calculate a second position at which the laser beam irradiates the first droplet using an output of the position sensor and generate a measurement signal including second information representing the second position; generate at least one of a first error signal and a second error signal from the determination signal and the measurement signal; generate a feedforward signal from the at least one of the first error signal and the second error signal; generate a feedback signal from the feedforward signal and a first positional difference between the first position and the second position in the first direction; and determine a second emission time point for a second specific period in which the droplet supplier supplies a second droplet into the chamber by adding the feedback signal to a reference signal, the reference signal including information representing a reference time point in the first specific period.

2. The semiconductor processing apparatus of claim 1, the controller is configured to calculate a positional difference between the first position and the second position to generate the at least one of the first error signal and the second error signal, wherein each of the first position of the determination signal and the second position of the measurement signal includes a first positional value in the first direction, a second positional value in the second direction, and a third positional value in a third direction perpendicular to the first direction and the second direction, wherein wherein the positional difference includes the first positional difference in the first direction, a second positional difference in the second direction, and a third positional difference in the third direction, and wherein the first error signal includes information representing the second positional difference, and the second error signal includes information representing the third positional difference.

3. The semiconductor processing apparatus of claim 1, the laser beam includes a first laser beam and a second laser beam, and wherein the second laser beam irradiates the first droplet after the first laser beam irradiates the first droplet. wherein 4. The semiconductor processing apparatus of claim 3, the determination signal includes the first information representing the first position at which the first laser beam is intended to irradiate the first droplet, and wherein the measurement signal includes the second information representing the second position at which the first laser beam irradiates the first droplet. wherein, 5. The semiconductor processing apparatus of claim 3, the determination signal includes the first information representing the first position at which the second laser beam is intended to irradiate the first droplet, and wherein the measurement signal includes the second information representing the second position at which the second laser beam irradiates the first droplet. wherein ​ The measurement signal includes the second information indicating the second position of the first droplet irradiated by the second laser beam.

6. The semiconductor processing apparatus of claim 1, wherein The feedforward signal includes a position compensation value in the first direction to adjust a position value of the determination signal in the first direction in the first specific period.

7. The semiconductor processing apparatus of claim 1, wherein The feedback signal includes information indicating a standby time in the first specific period.

8. The semiconductor processing apparatus of claim 7, wherein, The second emission time point is a time point after the standby time from the reference time point.

9. The semiconductor processing apparatus of claim 2, further comprising: a laser beam curtain generator configured to form a laser beam curtain at a plane defined by the second direction and the third direction; and a laser beam curtain sensor configured to sense the laser beam curtain reflected from the first droplet when the first droplet passes through the laser beam curtain.

10. The semiconductor processing apparatus of claim 9, wherein The controller is configured to determine a time point at which the laser beam curtain sensor senses the laser beam curtain reflected from the first droplet as the reference time point.

11. The semiconductor processing apparatus of claim 10, wherein The reference signal includes information indicating the reference time point in the first specific period.

12. The semiconductor processing apparatus of claim 1, wherein The first droplet is emitted within the first specific period.

13. The semiconductor processing apparatus of claim 1, wherein The position sensor includes at least one of a four-cell sensor and an image sensor.

14. A semiconductor processing apparatus comprising: a droplet supplier configured to form a droplet and supply the droplet to a chamber in a first direction; a light source generator configured to emit a laser beam in a second direction perpendicular to the first direction at a first emission time point such that extreme ultraviolet light is generated from the droplet; a position sensor disposed adjacent to the chamber; and a controller configured to receive a determination signal including information indicating a first position at which the droplet is expected to be irradiated by the laser beam, and the controller is configured to determine a second emission time point, wherein the controller is further configured to calculate a measurement signal including information indicating a second position of the droplet irradiated by the laser beam using an output of the position sensor, and generate an error signal including information indicating a difference between the first position of the determination signal and the second position of the measurement signal, wherein the determination signal, the measurement signal, and the error signal include position values in the first direction, the second direction, and a third direction perpendicular to the first direction and the second direction, respectively, within a specific period, wherein the controller is further configured to calculate a position compensation value in the first direction using at least one of a position value of the error signal in the second direction and a position value of the error signal in the third direction, and wherein the second emission time point is determined using a position value of the determination signal in the first direction, a position value of the measurement signal in the first direction, and a position compensation value in the first direction.

15. The semiconductor processing apparatus of claim 14, further comprising: a laser beam curtain generator configured to form a laser beam curtain at a plane defined by the second direction and the third direction; and a laser beam curtain sensor configured to sense the laser beam curtain reflected from the droplet when the droplet passes through the laser beam curtain.

16. The semiconductor processing apparatus of claim 15, wherein the controller is further configured to determine a time point at which the laser beam curtain sensor senses the laser beam curtain reflected from the droplet as a reference time point.

17. The semiconductor processing apparatus of claim 16, wherein, the controller is further configured to calculate a standby time using a moving speed of the droplet and a distance in the first direction between a first position of the droplet in the first direction at which the droplet passes through the laser beam curtain and a second position in the first direction, the second position in the first direction being obtained by adding the position value of the determination signal in the first direction to the position compensation value in the first direction.

18. The semiconductor processing apparatus of claim 17, wherein, the second emission time point is a time point after the standby time from the reference time point.

19. The semiconductor processing apparatus of claim 14, wherein the droplet is discharged in the certain period.

20. A semiconductor processing apparatus comprising: a droplet supplier configured to form a droplet and supply the droplet to a chamber in a first direction; a light source generator configured to emit a laser beam in a second direction perpendicular to the first direction at a first emission time point so that extreme ultraviolet light is generated from the droplet; a position sensor disposed adjacent to the chamber; and a controller configured to receive a determination signal including information representing a first position at which the droplet is expected to be irradiated by the laser beam, and the controller is configured to determine a second emission time point, wherein the controller is further configured to calculate a measurement signal including information representing a second position at which the laser beam irradiates the droplet using an output of the position sensor, and calculate an error signal including information representing a difference between the first position of the determination signal and the second position of the measurement signal, wherein the determination signal, the measurement signal, and the error signal include position values in a certain period in the first direction, the second direction, and a third direction perpendicular to the first direction and the second direction, respectively, and wherein the position value of the determination signal in the first direction is controlled such that the energy of the extreme ultraviolet light is increased at the position value of the measurement signal in the second direction and at the position value of the measurement signal in the third direction by determining the second emission time point using the position value of the error signal in the first direction to the third direction.

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