EUV exposure apparatus, overlay correction method, and semiconductor device manufacturing method

Abstract

An EUV exposure apparatus, a overlay correction method, and a semiconductor device manufacturing method are provided. The EUV exposure apparatus includes: an EUV light source; a first optical system configured to transmit EUV light from the EUV light source to an EUV mask; a second optical system configured to transmit EUV light reflected from the EUV mask to a wafer; a mask stage; a wafer stage; and a control unit configured to control the mask stage and the wafer stage, wherein, based on a correlation between a first overlay parameter and a second overlay parameter, the first overlay parameter is corrected by correcting the second overlay parameter, the first overlay parameter being one of parameters of overlay errors between layers on the wafer, the second overlay parameter being another of the parameters of the overlay errors.

Description

TECHNICAL FIELD

[0001] The present inventive concept relates to an exposure apparatus and an overlay correction method, and more particularly, to an exposure apparatus using extreme ultraviolet (EUV) light and an overlay correction method using the same. BACKGROUND

[0002] Recently, as the line width of a semiconductor circuit becomes finer, it has been necessary to use an exposure light source that emits a shorter wavelength during patterning of a circuit. For example, EUV light has been used as an exposure light source. Due to the absorption characteristics of EUV light, a reflective EUV mask is generally used in an EUV exposure process. A plurality of mirrors can be included in an illumination optical system for transmitting EUV light to the EUV mask and a projection optical system for projecting EUV light reflected from the EUV mask to an object to be exposed. As the difficulty of the exposure process increases, a small error occurring in the EUV mask and / or the mirror can cause a serious error in forming a pattern on a wafer. SUMMARY

[0003] The present inventive concept provides an extreme ultraviolet (EUV) exposure apparatus for improving an overlay error in an EUV exposure process, and an overlay correction method using the same and a semiconductor device manufacturing method.

[0004] According to an aspect of the present inventive concept, an EUV exposure apparatus includes an EUV light source configured to emit EUV light, a first optical system configured to transmit the EUV light from the EUV light source to an EUV mask, a mask stage configured to place the EUV mask thereon, a second optical system configured to transmit the EUV light reflected from the EUV mask to a wafer stage, and a control unit configured to control the mask stage and the wafer stage, and correct a first overlay parameter related to an overlay error between layers on a wafer by correcting a second overlay parameter based on a correlation between the first overlay parameter and the second overlay parameter, wherein the first overlay parameter is a parameter related to the overlay error between the layers on the wafer, and the second overlay parameter is another parameter related to the overlay error between the layers on the wafer.

[0005] According to another aspect of the present inventive concept, an EUV exposure apparatus includes an EUV light source, a mask stage configured to place an EUV mask thereon, and a control unit configured to control the mask stage and correct a first overlay parameter among overlay parameters between layers on a wafer by correcting a second overlay parameter, wherein the first overlay parameter is related to an error that increases three-dimensionally on both sides of an axis in a first direction perpendicular to a scanning direction of an EUV exposure process, and the second overlay parameter is related to an error that increases two-dimensionally in the scanning direction as a distance from the axis in the first direction increases.

[0006] According to another aspect of the present inventive concept, there is provided a method of overlay correction performed by an extreme ultraviolet (EUV) exposure apparatus, the method comprising: obtaining data on a first overlay parameter among parameters of overlay errors between layers on a wafer on which an EUV exposure process is performed, the first overlay parameter being related to an error that increases three-dimensionally on both sides of an axis in a first direction perpendicular to a scanning direction of the EUV exposure process; calculating a correction value of a second overlay parameter among the parameters of overlay errors based on a correlation between the first overlay parameter and the second overlay parameter, the second overlay parameter being related to an error that increases two-dimensionally in the scanning direction as a distance from the axis in the first direction increases; feeding back the correction value of the second overlay parameter within the EUV exposure apparatus; and correcting the first overlay parameter by correcting the second overlay parameter based on the correction value of the second overlay parameter.

[0007] According to another aspect of the present inventive concept, a semiconductor device manufacturing method using an extreme ultraviolet (EUV) exposure apparatus comprises: obtaining, by the EUV exposure apparatus, data on a first overlay parameter among parameters of overlay errors between layers on a first wafer on which an EUV exposure process is performed, the first overlay parameter being related to an error that increases three-dimensionally as a distance from a center point to both sides in a first direction perpendicular to a scanning direction in the EUV exposure process increases; calculating, by the EUV exposure apparatus, a correction value of a second overlay parameter among the parameters of overlay errors based on a correlation between the first overlay parameter and the second overlay parameter, the second overlay parameter being related to an error that increases two-dimensionally in the scanning direction as a distance to the center point in the first direction increases; feeding back the correction value of the second overlay parameter within the EUV exposure apparatus; performing, by the EUV exposure apparatus, the EUV exposure process on a second wafer; patterning the second wafer; and performing a subsequent semiconductor process on the second wafer, wherein performing the EUV exposure process on the second wafer comprises correcting the first overlay parameter by correcting the second overlay parameter based on the correction value of the second overlay parameter. BRIEF DESCRIPTION OF DRAWINGS

[0008] Example embodiments of the present inventive concept will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, and

[0009] Figure 1 is a conceptual view schematically showing an extreme ultraviolet (EUV) exposure apparatus according to an example embodiment of the present inventive concept;

[0010] Figure 2 is a detailed block diagram of a control unit included in the EUV exposure apparatus of Figure 1 ;

[0011] Figure 3A and Figure 3B are cross-sectional views for explaining overlay errors;

[0012] Figures 4A-4C is a conceptual diagram for explaining a parameter of overlay error;

[0013] Figure 5A and Figure 5B is a vector diagram and a graph for explaining a parameter RK12 of overlay error;

[0014] Figure 6A and Figure 6B is a vector diagram and a graph for explaining a parameter RK13 of overlay error;

[0015] Figures 7A-7D is a graph for explaining correction of a parameter RK13 of overlay error by an EUV exposure apparatus according to an example embodiment of the present inventive concept;

[0016] Figure 8A and Figure 8B is a flowchart schematically showing an overlay correction method using an EUV exposure apparatus according to some example embodiments of the present inventive concept; and

[0017] Figure 9A and Figure 9B is a flowchart schematically showing a semiconductor device manufacturing method using an EUV exposure apparatus according to some example embodiments of the present inventive concept. DETAILED DESCRIPTION

[0018] Hereinafter, example embodiments of the present inventive concept will be described in detail with reference to the accompanying drawings. Like elements in the drawings are denoted by like reference numerals and hereinafter not repeatedly described.

[0019] When the term "about" or "substantially" is used in this specification, it is intended that the relevant value includes manufacturing tolerances (e.g. ±10%) around the stated value. Furthermore, when the words "typically" and "substantially" are used in relation to a geometric shape, it is intended that precision of the geometric shape is not required, but that latitude in the shape is within the scope of the present disclosure. Furthermore, whether a value or shape is modified by "about" or "substantially", it will be understood that these values and shapes should be interpreted as including manufacturing or operational tolerances (e.g. ±10%) around the stated value or shape.

[0020] Figure 1 is a conceptual diagram of an extreme ultraviolet (EUV) exposure apparatus according to an example embodiment of the present inventive concept. Figure 2 is a detailed block diagram of a control unit included in the EUV exposure apparatus of Figure 1

[0021] Referring to Figure 1 and​Figure 2 The EUV exposure apparatus 100 can include an EUV light source 110, a first optical system 120, a second optical system 130, a mask stage 140, a wafer stage 150, a control unit 160, and a measurement apparatus 180.

[0022] The EUV light source 110 can be configured to generate and output high-energy density EUV light L1 in a wavelength range of about 5 nm to 50 nm. For example, the EUV light source 110 can generate and output high-energy density EUV light L1 having a wavelength of about 13.5 nm. The EUV light source 110 can be a plasma-based light source or a synchrotron light source. Here, the plasma-based light source refers to a light source that generates plasma and uses light emitted by the plasma, and can include a laser-produced plasma (LPP) light source, a discharge-produced plasma (DPP) light source, and / or other similar light sources. However, the EUV light source 110 is not limited thereto.

[0023] The plasma-based light source can include a condensing mirror such as an elliptical mirror and / or a spherical mirror configured to concentrate EUV light and thus increase the energy density of the illumination light incident on the first optical system 120.

[0024] The first optical system 120 can include a plurality of mirrors. For example, the first optical system 120 can include two or three mirrors. However, the number of mirrors of the first optical system 120 is not limited to two or three. The first optical system 120 can be configured to transmit the EUV light L1 from the EUV light source 110 to the EUV mask M. For example, the EUV light L1 from the EUV light source 110 can be reflected by the mirrors of the first optical system 120 to be incident on the EUV mask M placed on the mask stage 140. The first optical system 120 can deform the EUV light L1 into a curved slit form to be incident on the EUV mask M. Here, the curved slit form of the EUV light L1 can refer to a parabolic two-dimensional (2D) curve projected onto an x-y plane. The curved slit form of the EUV light L1 and effects thereof will be described in greater detail below. Figures 7A-7D The curved slit form of the EUV light L1 and effects thereof will be described in greater detail below.

[0025] The EUV mask M can be a reflective mask having a reflective region, a non-reflective region, and / or an intermediate reflective region. The EUV mask M can include a reflective multilayer film on a substrate and a pattern of an absorption layer on the reflective multilayer film. The substrate can include a low thermal expansion material (LTEM) such as quartz. The reflective multilayer film can include alternatingly stacked molybdenum (Mo) layers and silicon (Si) layers. For example, the Mo layers and the Si layers can be stacked into tens or more layers. The absorption layer can be formed of, for example, TaN, TaNO, TaBO, Ni, Au, Ag, C, Te, Pt, Pd, Cr, or the like. However, the material of the reflective multilayer film and the material of the absorption layer are not limited to the above-described materials. Here, the pattern of the absorption layer can correspond to the non-reflective region and / or the intermediate reflective region.

[0026] The EUV mask M can reflect the EUV light L1 incident thereon via the first optical system 120 to be incident on the second optical system 130. For example, the EUV mask M reflects the EUV light L1 from the first optical system 120 so that the EUV light L1 is structured according to the shape of the pattern of the reflective multilayer film and the absorption layer on the substrate to be incident on the second optical system 130. The EUV light L1 can be structured to include at least second or higher order diffracted light based on the pattern on the EUV mask M. The structured EUV light L1 containing information about the shape of the pattern on the EUV mask M is incident on the second optical system 130 and projected to the EUV exposure object W by the second optical system 130 to form a pattern corresponding to the shape of the pattern. The EUV exposure object W can be a substrate containing a semiconductor material such as silicon, for example, a wafer. Hereinafter, the EUV exposure object W and the wafer should be understood as the same concept unless otherwise specified.

[0027] The EUV mask M can be on a mask stage 140. The mask stage 140 can be configured to move in an x-axis direction and / or a y-axis direction on an x-y plane and to move in a z-axis direction perpendicular to the x-y plane. The mask stage 140 can be configured to rotate about the z-axis on the x-y plane and / or to rotate about one axis (e.g., the x-axis or the y-axis) on the x-y plane on a y-z plane and / or an x-z plane. Due to the movement of the mask stage 140, the EUV mask M can move in the x-axis direction, the y-axis direction, and / or the z-axis direction, and / or rotate about the x-axis, the y-axis, and / or the z-axis.

[0028] The EUV exposure object W (e.g., a wafer) can be on the wafer stage 150. The wafer stage 150 can be configured to hold the EUV exposure object W during the EUV exposure. The wafer stage 150 can be configured to move in an x-axis direction and / or a y-axis direction on an x-y plane and configured to move in a z-axis direction perpendicular to the x-y plane. The wafer stage 150 can be configured to rotate on the z-axis in the x-y plane and / or rotate on one axis (e.g., the x-axis and / or the y-axis) on the x-y plane in the y-z plane and / or the x-z plane. Due to the movement of the wafer stage 150, the EUV exposure object W can move in the x-axis direction, the y-axis direction, and / or the z-axis direction, and / or rotate on the x-axis, the y-axis, and / or the z-axis.

[0029] The second optical system 130 can include a plurality of mirrors. Although, for ease of explanation, Figure 1 The second optical system 130 is shown to include two mirrors (the first mirror 132 and the second mirror 134), but the second optical system 130 can include more than two mirrors. For example, in the EUV exposure apparatus 100 of the present embodiment, the second optical system 130 can include four to eight mirrors. However, the number of mirrors of the second optical system 130 is not limited to four to eight.

[0030] As described above, the second optical system 130 can be configured to reflect the EUV light L1 reflected from the EUV mask M by the mirrors to transmit it to the EUV exposure object W. Further, the second optical system 130 can allow the EUV light L1 to be incident on the upper surface of the EUV exposure object W at a specific angle. For example, the second optical system 130 can allow the EUV light L1 to be incident on the upper surface of the EUV exposure object W at an incident angle of about 6° with respect to a normal line perpendicular to the upper surface of the EUV exposure object W.

[0031] The control unit 160 can be configured to control the mask stage 140 and the wafer stage 150. The control unit 160 will be described in more detail below with reference to Figure 2 The control unit 160 will be described in more detail.

[0032] The measurement apparatus 180 can be configured to measure a critical dimension (CD) and / or an overlay error of a pattern on a wafer. The measurement apparatus 180 can include an optical microscope and / or an electron microscope such as a scanning electron microscope (SEM) or a transmission electron microscope (TEM). The measurement apparatus 180 can be configured to use an ellipsometry method such as an imaging ellipsometry technique (IE) or a spectroscopic ellipsometry technique (SIE) as a measurement method. However, the measurement method used by the measurement apparatus 180 is not limited to the ellipsometry method.

[0033] In the present embodiment, the EUV exposure apparatus 100 includes the measurement apparatus 180, but in another embodiment, the measurement apparatus 180 can be implemented separately from the EUV exposure apparatus 100. The CD or overlay error of the pattern on the wafer can be measured by the measurement apparatus 180 through after-development inspection (ADI) and / or after-clean inspection (ACI).

[0034] Reference will now be made to Figure 2 The control unit 160 will be described in more detail. The control unit 160 can include a mask stage controller 162, a wafer stage controller 164, a main controller 166, and a data acquisition unit 168.

[0035] The mask stage controller 162 can be configured to control the movement of the mask stage 140. Here, the movement of the mask stage 140 can include movement in the x-axis direction, the y-axis direction, and / or the z-axis direction, and / or rotation around the x-axis, the y-axis, and / or the z-axis.

[0036] The wafer stage controller 164 can be configured to control the movement of the wafer stage 150. The movement of the wafer stage 150 can also include movement in the x-axis direction, the y-axis direction, and / or the z-axis direction, and / or rotation around the x-axis, the y-axis, and / or the z-axis.

[0037] The main controller 166 can include an alignment controller 166a and a feedback unit 166b. The alignment controller 166a can be configured to calculate correction values of parameters of overlay errors. The correction values of the parameters of the overlay errors can be calculated based on data on the parameters of the overlay errors and the correlation between the parameters of the overlay errors. Here, the parameters of the overlay errors can refer to parameters related to the overlay errors between the layers on the EUV exposure object W. The parameters of the overlay errors will be referred to as “overlay parameters” hereinafter.

[0038] For reference, the overlay error can refer to the difference in the overlap between the lower layer and the current layer as the upper layer. Generally, when performing an exposure process on the upper layer based on an overlay mark or the like on the lower layer, the overlay error is minimized by performing a shot to align with the lower layer as much as possible. When the overlay error is large (for example, when the difference in the relative position between the lower layer and the current layer is large), the performance of the semiconductor device can be adversely affected by the overlay error.

[0039] In the EUV exposure apparatus 100 of the present embodiment, for example, the alignment controller 166a can calculate the correction value of the second overlay parameter from the data of the first overlay parameter based on the correlation between the first overlay parameter and the second overlay parameter. Here, the first overlay parameter can be the parameter RK13 among the overlay parameters, and the second overlay parameter can be the parameter RK12 among the overlay parameters. Reference will be made to Figures 3A-6BParameters of overlay errors (e.g., overlay parameters) between layers on a wafer are described in more detail.

[0040] The feedback unit 166b can be configured to feed back the calculated correction value of the overlay parameter to the mask stage controller 162 and / or the wafer stage controller 164. The mask stage controller 162 and / or the wafer stage controller 164 can be configured to control the movement of the mask stage 140 and / or the wafer stage 150 based on the correction value of the overlay parameter. For example, the feedback unit 166b can feed back the calculated correction value of the second overlay parameter (parameter RK12) to the mask stage controller 162, and the mask stage controller 162 can control the rotation of the mask stage 140 around the x-axis based on the correction value of the second overlay parameter.

[0041] The main controller 166 can be configured to control the mask stage controller 162 and the wafer stage controller 164 as a whole. For example, the main controller 166 can be configured to control the mask stage controller 162 and the wafer stage controller 164 to be synchronized with each other in the scanning direction during the exposure process.

[0042] Although not shown in Figure 2 , the main controller 166 can further include various components for the control of the EUV exposure process. For example, the main controller 166 can include a focus controller, a data storage, an exposure processor, etc.

[0043] The focus controller can be configured to compare the measured focus offset with the required focus offset to obtain a focus correction value and transmit the focus correction value to the wafer stage controller 164 through the feedback unit 166b so that the wafer stage controller 164 can control the movement of the wafer stage 150. The data storage can store data such as the correction value of the overlay parameter calculated by the alignment controller 166a and / or the focus controller, the correlation between the overlay parameters, the focus correction value, etc. The exposure processor can be configured to perform the exposure process while the mask stage 140 and the wafer stage 150 are synchronized with each other in the scanning direction by the main controller 166 after the mask stage 140 is moved.

[0044] When the measurement device 180 is included in the EUV exposure apparatus 100, the main controller 166 can further include a measurement controller. The measurement controller can be configured to control and / or guide the measurement device 180 to measure data related to the required overlay parameter.

[0045] The data acquisition unit 168 can be configured to receive data on the overlay parameters by the measurement device 180 and transmit the data to the main controller 166. For example, an overlay error in a pattern on a wafer can be measured by the measurement device 180, and the data acquisition unit 168 can receive data on the overlay error from the measurement device 180. Thus, the data acquisition unit 168 can obtain data on the required overlay parameters from the measurement device 180 and transmit the data to the main controller 166. In the EUV exposure apparatus 100 of the present embodiment, the data acquisition unit 168 can obtain data on, for example, the first overlay parameter (e.g., the parameter RK13) by the measurement device 180 and transmit the data to the alignment controller 166a of the main controller 166. However, the data on the overlay parameters obtained by the data acquisition unit 168 is not limited to the data on the parameter RK13.

[0046] The control unit 160 and / or the controllers and units included in the control unit 160 (e.g., the mask stage controller 162, the main controller 166, the data acquisition unit 168, the wafer stage controller 164, the focus controller, and / or the exposure processor) can include a processing circuit such as hardware including a logic circuit, a hardware / software combination such as a processor executing software, or a combination thereof. For example, the processing circuit can more specifically include, but is not limited to, a central processing unit (CPU), an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable gate array (FPGA), a programmable logic unit, a microprocessor, an application specific integrated circuit (ASIC), a memory coupled to a processor, and the like.

[0047] The EUV exposure apparatus 100 of the present embodiment can adjust a second overlay parameter to correct a first overlay parameter related to the second overlay parameter, thereby greatly improving the EUV process by minimizing and / or preventing overlay errors in the EUV exposure process. Here, the first overlay parameter can correspond to the parameter K13, and the second overlay parameter can correspond to the parameter K12. The parameter K13 can be an overlay parameter that cannot be corrected by physical actuation of the EUV exposure apparatus 100. The physical actuation can refer to a physical operation of a scanner (e.g., an exposure apparatus) for correcting an overlay error. For example, the physical operation can include various methods (e.g., a method of applying pressure to a lens or a mirror in an optical system and / or tilting or rapidly moving the lens or the mirror; a method of moving a mask by the mask stage 140 or moving an EUV exposure object W by the wafer stage 150; a method of heating the EUV exposure object W; and the like). Here, when an overlay parameter is related to a physical actuation of an intermediate mask (e.g., a mask), an indicator "R" can be added to the symbol of the parameter. For example, when the parameter K12 and the parameter K13 are related to a physical actuation of a mask, the parameter K12 and the parameter K13 can be referred to as the parameter RK12 and the parameter RK13, respectively.

[0048] The EUV exposure apparatus 100 can be configured to determine that an overlay error has occurred in the manufacturing of a semiconductor device for an electronic device and determine an overlay parameter of the overlay error. In a case where an overlay parameter (e.g., a first overlay parameter) cannot be directly corrected by physical actuation, the control unit 160 can adjust a second overlay parameter to correct the first overlay parameter. In a case where the overlay error is still within an allowable tolerance of an error, the semiconductor device having the detected overlay error can still be incorporated into the electronic device, and then a subsequent semiconductor device is manufactured based on the adjustment; and / or the EUV exposure apparatus 100 can indicate that the semiconductor device is defective, and then a subsequent semiconductor device is manufactured based on the adjustment.

[0049] For reference, overlay parameters can be classified in various ways, and in particular, some of the overlay parameters cannot be directly corrected due to hardware limitations of an EUV scanner or an EUV exposure apparatus. For example, the parameter RK13 among the overlay parameters refers to a third-order function type overlay distortion in an x-axis direction perpendicular to a scanning direction. In a conventional argon fluoride immersion (ArFi) scanner, the parameter RK13 is correctable by physical actuation. However, due to control limitations in an EUV scanner having a hardware configuration different from that of the ArFi scanner, the parameter RK13 cannot be directly corrected by physical actuation. Accordingly, the parameter RK13 among the overlay parameters is classified as a parameter that cannot be directly corrected in an EUV exposure process. The following will be described with reference to FIG. 2. Figures 4A-4C The types of overlay parameters are described in more detail.

[0050] Figure 3A and Figure 3B is a cross-sectional view for illustrating an overlay error.

[0051] Referring to Figure 3A and Figure 3B , the overlay error can be measured by measuring a first overlay mark OM1 on a first layer 210 as a lower layer and a second overlay mark OM2 on a second layer 220 as an upper layer and calculating a difference in a relative position between the first overlay mark OM1 and the second overlay mark OM2. The first overlay mark OM1 can be formed when a pattern is formed on the first layer 210, and the second overlay mark OM2 can be formed later when a pattern is formed on the second layer 220. The first overlay mark OM1 and the second overlay mark OM2 can be formed on a scribe lane of a wafer and formed in a box pattern form and / or a bar pattern form. However, the shape or position of the first overlay mark OM1 and the second overlay mark OM2 are not limited thereto.

[0052] Figure 3B A semiconductor device on a semiconductor substrate 201 is shown. Specifically, a transistor TR includes a source / drain region (S / D) 202 and a gate electrode 210g. The transistor TR can be formed on the semiconductor substrate 201, and a vertical contact 220c connected to the gate electrode 210g can be formed. The gate electrode 210g can correspond to a pattern formed on a first layer 210 as a lower layer, and the vertical contact 220c can correspond to a pattern formed on a second layer 220 as an upper layer. When there is no overlay error, the vertical contact 220c can be on a central portion of the gate electrode 210g with respect to a first direction (e.g., an x-axis direction). However, as shown, Figure 3B due to various reasons, a first overlay error OE1 can occur between the gate electrode 210g and the vertical contact 220c in the first direction (x-axis direction). When the first overlay error OE1 is large, the vertical contact 220c can be connected to an edge portion of the gate electrode 210g unstably, connected to the source / drain region 202 beyond the gate electrode 210g, and / or connected to both the gate electrode 210g and the source / drain region 202 while overlapping a portion of the gate electrode 210g. The structure of the vertical contact 220c having the first overlay error OE1 can cause serious errors such as open-fault and / or short-fault of the transistor TR.

[0053] Figures 4A-4C is a conceptual diagram of a parameter (e.g., an overlay parameter) for illustrating an overlay error.

[0054] Figure 4ALinear parameters are shown, which are first order parameters among the overlay parameters. For example, a parameter K1 can be a parameter related to overlay error occurring at one side in a first direction (e.g., x-axis direction) with a constant size. A parameter K2 can be a parameter related to overlay error occurring at one side in a second direction (e.g., y-axis direction) with a constant size. When overlay error occurring in the first direction (e.g., x-axis direction) is dx and overlay error occurring in the second direction (e.g., y-axis direction) is dy, the parameter K1 can be expressed as dx = k1, and the parameter K2 can be expressed as dy = k2. Here, the second direction (e.g., y-axis direction) corresponds to a scanning direction in the EUV exposure process, and the first direction (e.g., x-axis direction) can be a direction perpendicular to the second direction (e.g., y-axis direction). The first direction (e.g., x-axis direction) can correspond to a direction in which the EUV light extends in a curved slit form.

[0055] A parameter K3 can be a parameter related to overlay error occurring at both sides in the first direction (e.g., x-axis direction) with a size proportional to a position and including mirror symmetry across the y-axis. A parameter K4 can be a parameter related to overlay error occurring at both sides in the second direction (e.g., y-axis direction) with a size proportional to a position and including mirror symmetry across the x-axis. Thus, the parameter K3 can be expressed as dx = k3 * x, and the parameter K4 can be expressed as dy = k4 * y.

[0056] In addition to the parameters K1 to K4, the linear parameters can include a parameter K5 expressed as dx = k5 * y and a parameter K6 expressed as dy = k6 * x.

[0057] Figure 4B Parameters as second order parameters among the overlay parameters are shown. For example, a parameter K7 can be a parameter related to overlay error occurring at both sides in the first direction (e.g., x-axis direction) with a size proportional to a square of a position. A parameter K8 can be a parameter related to overlay error occurring at both sides in the second direction (e.g., y-axis direction) with a size proportional to a square of a position. A parameter K12 can be a parameter related to overlay error occurring at both sides in the first direction (e.g., x-axis direction) and in the second direction (e.g., y-axis direction) with a size proportional to a square of a position. Thus, the parameter K7 can be expressed as dx = k7 * x 2 , the parameter K8 can be expressed as dy = k8 * y 2 , and the parameter K12 can be expressed as dy = k12 * x 2 .

[0058] In addition to the parameters K7, K8 and K12, the second order parameters can include a parameter K9 expressed as dx = k9 * x * y, a parameter K10 expressed as dy = k10 * y * x, and a parameter K11 expressed as dx = k11 * y 2 .

[0059] Figure 4C Parameters that are third order parameters among the overlay parameters are shown. For example, the parameter K13 can be a parameter related to an overlay error that occurs on both sides in a first direction (e.g., x-axis direction) in a size proportional to a cube of a position, and the parameter K14 can be a parameter related to an overlay error that occurs on both sides in a second direction (e.g., y-axis direction) in a size proportional to a cube of a position. Thus, the parameter K13 can be expressed as dx = k13 * x 3 , and the parameter K14 can be expressed as dy = k14 * y 3 .

[0060] In addition to the parameters K13 and K14, the third order parameters can include a parameter K15 expressed as dx = k15 * x 2 * y, a parameter K16 expressed as dy = k16 * y 2 * x, a parameter K17 expressed as dx = k17 * x * y 2 , a parameter K18 expressed as dy = k18 * y * x 2 , a parameter K19 expressed as dx = k19 * y 3 , and a parameter K20 expressed as dy = k20 * x 3 .

[0061] As described above, in an ArFi exposure apparatus, all of the overlay parameters are correctable by physical actuation. In an EUV exposure apparatus, most of the overlay parameters are similar to the ArFi exposure apparatus and are correctable by physical actuation. However, in the EUV exposure apparatus, it is almost impossible to directly correct the K13 parameter by physical actuation.

[0062] Figure 5A and Figure 5B are a vector diagram and a graph for illustrating a parameter RK12 of an overlay error. In the graph of Figure 5B , the horizontal axis represents a position Pos., and the vertical axis represents an overlay error Err., and the units on the horizontal and vertical axes are arbitrary units (a.u.) representing relative sizes.

[0063] Referring to Figure 5A and Figure 5B , Figure 5AThe size and direction of the vector 50 can represent the size and direction of the overlay error. Thus, it can be seen that the size of the overlay error associated with the parameter RK12 increases in the second direction (e.g., the y-axis direction) as the distance from the center increases in the first direction (e.g., the x-axis direction). The size of the overlay error associated with the parameter RK12 can increase two-dimensionally in the second direction (e.g., the y-axis direction) with respect to the position in the first direction (e.g., the x-axis direction). That is, the size of the overlay error associated with the parameter RK12 in the second direction (e.g., the y-axis direction) can increase in proportion to the square of the position in the first direction (e.g., the x-axis direction).

[0064] Figure 5B is a graph showing that the size of the overlay error associated with the parameter RK12 increases two-dimensionally with respect to the position. As a reference, Figure 5A The rectangle S of the vector 50 can be in a form corresponding to one shot in the exposure process. Thus, the size of the overlay error in the second direction (e.g., the y-axis direction) is largest at portions corresponding to both sides of the one shot, and the overlay error having substantially the same form as this overlay error repeatedly occurs in the adjacent subsequent shots.

[0065] Figure 6A and Figure 6B is a vector graph and a graph of the parameter RK13 for illustrating the overlay error. In Figure 6B In the graph of the vector 50, the horizontal axis represents the position Pos., and the vertical axis represents the overlay error Err., and the units on the x-axis and the y-axis are arbitrary units representing relative sizes.

[0066] Referring to Figure 6A and Figure 6B , Figure 6A The size and direction of the vector 55 can represent the size and direction of the overlay error. Thus, it can be seen that the size of the overlay error associated with the parameter RK13 increases as the distance from the center increases in the first direction (e.g., the x-axis direction). The size of the overlay error associated with the parameter RK13 can increase three-dimensionally in the first direction (e.g., the x-axis direction) with respect to the position in the first direction (e.g., the x-axis direction). That is, the size of the overlay error associated with the parameter RK13 in the first direction (e.g., the x-axis direction) can increase in proportion to the cube of the position in the first direction (e.g., the x-axis direction).

[0067] Figure 6B is a graph showing that the size of the overlay error associated with the parameter RK13 increases three-dimensionally with respect to the position. As described above with reference to Figure 5A and Figure 5B , Figure 6AThe rectangle S can be in a form corresponding to one irradiation in an exposure process, and the size of the overlay error can be largest at portions corresponding to both sides of the irradiation. Further, the overlay error can repeatedly occur in substantially the same form in adjacent subsequent irradiations.

[0068] Figures 7A-7D is a graph for illustrating a parameter RK13 for correcting an overlay error in an EUV exposure apparatus according to an example embodiment of the present inventive concept. It will be described with reference to Figure 1 and Figure 2 Figures 7A-7D .

[0069] With reference to Figures 7A-7D , Figure 7A is a result of simplifying Figure 5B and Figure 6B graphs in which overlay errors related to the parameters RK12 and RK13 are shown. Figure 7B EUV light in the form of a curved slit in a three-dimensional (3D) x-y-z space is shown. Here, a second direction (e.g., y-axis direction) is a scanning direction in an EUV exposure process, and a first direction (e.g., x-axis direction) is a direction perpendicular to the second direction (e.g., y-axis direction). A third direction (e.g., z-axis direction) corresponds to a direction orthogonal to an upper surface of an EUV exposure object W and can be a direction perpendicular to an x-y plane.

[0070] The x-y plane can correspond to a lower surface of an EUV mask M on which an absorption layer pattern is formed. Thus, EUV light from an EUV light source 110 can be incident on the lower surface (e.g., a shadow portion on the x-y plane of the EUV mask M) of the EUV mask M in the form of a curved slit via a first optical system 120. Thus, the curved slit drawn on the shadow portion can correspond to the EUV light Le. Figure 7B

[0071] In general, in order to correct an overlay error related to the parameter RK12 (hereinafter simply referred to as “parameter RK12 correction”), a method of rotating the EUV mask M about the x-axis (as indicated by a curved arrow) can be used. More specifically, the overlay error related to the parameter RK12 can be corrected by rotating the EUV mask M by rotating a mask stage 140 on which the EUV mask M is placed by a mask stage controller 162.

[0072] However, due to the non-telecentric characteristics of the EUV exposure apparatus 100 and the EUV light incident on the EUV mask M in the form of a curved slit, when a change in a component of the EUV light in the third direction (e.g., z-axis direction) occurs during the rotation about the x-axis, not only a component of the EUV light in the second direction (e.g., y-axis direction), but also a component of the EUV light in the first direction (e.g., x-axis direction) changes. Figure 7C ​​is a graph showing this process, in which the components of the EUV light in the form of a curved slit in a first direction (e.g., the x-axis direction) and a second direction (e.g., the y-axis direction) are simultaneously changed when the EUV mask M is rotated around the x-axis. In Figure 7C By the rotation of the EUV mask M around the x-axis, the EUV light in the form of a curved slit can be changed so that the central portion is lowered and the two outer portions are raised in the y-axis direction, or vice versa. For example, by the rotation of the EUV mask M around the x-axis, the EUV light in the form of a curved slit can be changed so that the central portion is raised and the two outer portions are lowered in the y-axis direction.

[0073] Therefore, in order to correct the parameter RK12, the overlay parameter that is a parasitic parameter with respect to the first direction (e.g., the x-axis direction) can be corrected when the EUV mask M is rotated around the x-axis. For example, due to the correction of the parameter RK12, the parameter RK3 or the parameter RK13, or the like, which is a parasitic parameter, can be corrected.

[0074] When the relationship between the overlay parameters that affect each other is referred to as correlation, the correlation between the parameters RK12 and RK13 can be expressed as 1:K, which is the ratio between the correction value of the parameter RK12 that is corrected by the rotation of the EUV mask M around the x-axis and the correction value of the parameter RK13, which is a parasitic parameter that is corrected due to the correction of the parameter RK12, where K can be in the range of -0.25 to -0.45.

[0075] As shown in the left graph of Figure 7D When the absolute value of the error Err increases according to the position Pos. in the x-axis direction in the first and third quadrants, the correction value of the parameter RK13 can have a (+) sign, as shown in the right graph of Figure 7D When the absolute value of the error Err increases according to the position Pos. in the x-axis direction in the second and fourth quadrants, the correction value of the parameter RK13 can have a (-) sign, as shown in the right graph of

[0076] As an example, as shown in Table 1 below, when the parameter RK12 is corrected by about 1 as input by the rotation of the EUV mask M around the x-axis, the parameter RK12 can be corrected by about 1.02 as the first output Output1. As described above, due to the physical limitations of the actuators for the stage movement in the EUV exposure apparatus, the set acquisition accuracy, which is the difference between the input and the output, cannot be 100%.

[0077] [Table 1]

[0078] Input First output Second output Third output 1 *RK12 RK12: 1.02 *RK12 RK3: 0.21 *RK12 RK13: -0.35 *RK12

[0079] It can be seen that the parameter RK3 is corrected by about 0.21 as the second output Output2, and the parameter RK13 is corrected by about -0.35 as the third output Output3. As described above, the parameters RK3 and RK13 are parasitic parameters generated during the correction of the parameter RK12.

[0080] For reference, when the correlation between the parameters RK12 and RK13 is explained in more specific values by the rotation of the EUV mask M around the x-axis, when the rotation of the EUV mask M around the x-axis corrects the overlay error of about 3 nm per cm 2 of the parameter RK12, it can correct the overlay error of about -1 nm per cm 2 of the parameter RK13.

[0081] The EUV exposure apparatus 100 of the present embodiment can correct the parameter RK13, which is a parasitic parameter, by correcting the parameter RK12 according to the correlation between the parameters RK12 and RK13. Therefore, the EUV exposure apparatus 100 of the present embodiment can substantially correct the parameter RK13, which is classified as an overlay parameter that cannot be directly corrected. Further, the parameter RK13 is related to the overlay error in the x-axis direction, which has a very small process margin. Therefore, the parameter RK13 cannot be directly controlled and corrected by the current EUV exposure apparatus 100. On the contrary, the parameter RK12 is related to the overlay error in the y-axis direction, which has a large process margin. Therefore, the parameter RK12 is easily directly controlled and corrected, and the parameter RK13 can be indirectly corrected by correcting the parameter RK12 within the process margin.

[0082] The correction of the parameter RK12 and the indirect correction of the parameter RK13, which is a parasitic parameter, can be performed by performing several feedback processes. For example, the correction of the parameter RK12 can be performed several times for the optimal correction of the parameter RK13.

[0083] Figure 8A and Figure 8B are flowcharts schematically showing an overlay correction method using an EUV exposure apparatus according to an example embodiment of the present inventive concept. Reference will be made to Figure 1 and Figure 2 described Figure 8A and Figure 8B .

[0084] Reference will be made to Figure 8AIn the overlay correction method of the present example embodiment using the EUV exposure apparatus (hereinafter simply referred to as "overlay correction method"), first, data on a first overlay parameter is obtained (S110). The first overlay parameter can be, for example, the parameter RK13, which is classified as a parameter that cannot be directly adjusted by the EUV exposure apparatus. Therefore, the data on the first overlay parameter can be understood as data on a overlay error related to the parameter RK13 and occurring in the EUV exposure object W on which the EUV exposure process is performed. The data on the first overlay parameter can be obtained by the data acquisition unit 168 through the measurement device 180. The data on the first overlay parameter can be obtained as ADI or ACI data through the measurement device 180.

[0085] Next, based on a correlation between the first overlay parameter and the second overlay parameter, a correction value of the second overlay parameter is calculated (S120). As described above, the correction value of the second overlay parameter can be calculated by the alignment controller 166a. The correlation between the first overlay parameter and the second overlay parameter can refer to a ratio between the correction value of the second overlay parameter and the correction value of the first overlay parameter. In the overlay correction method of the present embodiment, the correlation can be expressed as 1:K, and K can be in the range of about -0.25 to -0.45.

[0086] For example, when K is -0.35 and the correction value of the first overlay parameter is 1 based on the data on the first overlay parameter obtained by the data acquisition unit 168, the correction value of the second overlay parameter can be calculated as the first overlay parameter (1) divided by K (-0.35). In the present example, based on the correlation, the correction value of the second overlay parameter will be equal to -2.86.

[0087] Next, the calculated correction value of the second overlay parameter is fed back for the EUV exposure process performed on a subsequent batch (e.g., a subsequent wafer and / or wafer group) (S130). Here, a batch refers to a process quantity unit of the exposure object W on which the exposure process is performed under the same process conditions after the process conditions for the exposure process are controlled. For example, the correction value of the second overlay parameter calculated by the alignment controller 166a can be transmitted to the feedback unit 166b, and then fed back to the mask stage controller 162 through the feedback unit 166b.

[0088] Finally, in the EUV exposure process for the subsequent lot, the second overlay parameter is corrected and the first overlay parameter, which is a parasitic parameter, is corrected according to the correction of the second overlay parameter (S140). More specifically, the mask stage controller 162 controls the movement of the mask stage 140 based on the corrected value of the second overlay parameter. For example, in order to correct the parameter RK12, the mask stage controller 162 controls the rotation of the mask stage 140 around the x-axis based on the corrected value of the second overlay parameter. Thereafter, the EUV exposure process is performed on the subsequent lot to correct the second overlay parameter (e.g., the parameter RK12), and the first overlay parameter (e.g., the parameter RK13), which is a parasitic parameter, can be corrected according to the correction of the parameter RK12.

[0089] Referring to Figure 8B , the overlay correction method of the present embodiment is similar to the overlay correction method of Figure 8A , but can differ from the overlay correction method of Figure 8A in that an operation is further performed to repeatedly provide feedback. Specifically, in the overlay correction method of the present embodiment, the obtaining of data on the first overlay parameter (S110), the calculation of the corrected value of the second overlay parameter (S120), the feedback of the corrected value of the second overlay parameter (S130), and the correction of the first overlay parameter through the correction of the second overlay parameter (S140) are sequentially performed. Here, the first overlay parameter can be the parameter RK13, the second overlay parameter can be the parameter RK12, and the above operations are as described above with reference to Figure 8A .

[0090] Next, it is determined whether the correction of the first overlay parameter is appropriate (S150). In other words, it is determined whether the degree of correction of the first overlay parameter through the correction of the second overlay parameter is within a required range. In determining whether the correction of the first overlay parameter is appropriate, the appropriateness of the correction of the second overlay parameter can be determined.

[0091] When the correction of the first overlay parameter is appropriate (Yes), the overlay correction method of the present embodiment ends.

[0092] When the correction of the first overlay parameter is not appropriate (No), the reason therefor is analyzed and the corrected value of the second overlay parameter is calculated again (S160). In consideration of the above reason, the corrected value of the second overlay parameter can be calculated from the correlation between the first overlay parameter and the second overlay parameter. Thereafter, the method returns to the feedback of the corrected value of the second overlay parameter (S130) and the subsequent operations are repeatedly performed until the first overlay parameter is appropriately corrected.

[0093] Figure 9A and Figure 9B are flowcharts schematically showing a semiconductor device manufacturing method using an EUV exposure apparatus according to an example embodiment of the present inventive concept. Reference will be made to Figure 1 andFigure 2 Description Figure 9A and Figure 9B The above description of Figure 1 and Figure 2 will be briefly provided or omitted here.

[0094] Referring to Figure 9A , in a semiconductor device manufacturing method using an EUV exposure apparatus according to an embodiment of the present inventive concept (hereinafter simply referred to as "semiconductor device manufacturing method"), obtaining data on a first overlay parameter (S210), calculating a correction value of a second overlay parameter (S220), and feeding back the correction value of the second overlay parameter (S230) are sequentially performed. Here, the first overlay parameter can be the parameter RK13, and the second overlay parameter can be the parameter RK12, and the above operations are as described above with reference to Figure 8A .

[0095] Next, an EUV exposure process is performed on the wafer (S240). The EUV exposure process performed on the wafer can be a process in which EUV light is incident on the EUV mask M in a curved slit form through the first optical system 120 and the EUV light reflected from the EUV mask M is projected to the EUV exposure object W (e.g., wafer) through the second optical system 130. Here, the EUV light can be projected to a photoresist (PR) on the wafer. The EUV exposure process performed on the wafer can further include forming a PR pattern by performing a developing process and a cleaning process on the PR.

[0096] The EUV exposure process performed on the wafer (S240) can be substantially the same as the correction of the first overlay parameter by the correction of the second overlay parameter described above with reference to Figure 8A . However, in order to emphasize the relationship with the subsequent operation, the expression "EUV exposure process on the wafer" is used here. Thus, the EUV exposure process performed on the wafer (S240) can include correcting the first overlay parameter by correcting the second overlay parameter.

[0097] After the EUV exposure process performed on the wafer (S240), the wafer is patterned (S250). The patterning of the wafer can refer to a process of forming a pattern on the wafer by an etching process using the PR pattern as a mask. The pattern on the wafer can be understood to mean that the pattern of the absorption layer of the EUV mask M is transferred to the wafer by the exposure process and the etching process.

[0098] Thereafter, a subsequent semiconductor process is performed on the wafer (S260). The subsequent semiconductor process can include various processes. For example, the subsequent semiconductor process can include a deposition process, an etching process, an ion process, a cleaning process, and the like. The subsequent semiconductor process can also include a singulation process to individualize the wafer into semiconductor chips, a testing process to test the semiconductor chips, and a packaging process to package the semiconductor chips. The semiconductor device can be completed by performing the subsequent semiconductor process on the wafer.

[0099] Referring to Figure 9B , the semiconductor device manufacturing method of the present embodiment is similar to the semiconductor device manufacturing method of Figure 9A , but can differ from the semiconductor device manufacturing method of Figure 9A in that an operation is further performed to repeatedly provide feedback. Specifically, in the semiconductor device manufacturing method of the present embodiment, obtaining data on a first overlay parameter (S210), calculating a correction value of a second overlay parameter (S220), feeding back the correction value of the second overlay parameter (S230), and performing an EUV exposure process on a wafer (S240) are sequentially performed. Here, the first overlay parameter can be the parameter RK13, and the second overlay parameter can be the parameter RK12, and the above operations are as described above with reference to Figure 9A .

[0100] Next, it is determined whether the correction of the first overlay parameter is appropriate (S242). For example, it is determined whether the degree of correction of the first overlay parameter by the correction of the second overlay parameter is within a required range. When it is determined whether the correction of the first overlay parameter is appropriate, the appropriateness of the correction of the second overlay parameter can be determined.

[0101] When the correction of the first overlay parameter is appropriate (Yes), patterning of the wafer (S250) and performing a subsequent semiconductor process on the wafer (S260) are sequentially performed, after which the semiconductor device manufacturing method of the present embodiment ends.

[0102] When the correction of the first overlay parameter is not appropriate (No), a reason therefor is analyzed and a correction value of the second overlay parameter is again calculated (S244). The correction value of the second overlay parameter can be calculated from a correlation between the first overlay parameter and the second overlay parameter in consideration of the above reason. Thereafter, the method returns to feeding back the correction value of the second overlay parameter (S130) and the subsequent operations are repeatedly performed until the first overlay parameter is appropriately corrected.

[0103] While the present inventive concept has been particularly shown and described with reference to embodiments thereof, it will be understood that various changes in form and details can be made therein without departing from the spirit and scope of the appended claims.

[0104] This application claims the benefit of Korean Patent Application No. 10-2020-0050351, filed April 24, 2020, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.

Claims

1. An EUV exposure apparatus, comprising: EUV light source, configured to emit EUV light; A first optical system is configured to transmit the EUV light from the EUV source to an EUV mask; A mask platform configured to place the EUV mask thereon; A second optical system is configured to transmit the EUV light reflected from the EUV mask to the wafer platform; as well as The control unit is configured to control the mask platform and the wafer platform and to correct the first overlay parameter by correcting the second overlay parameter based on the correlation between the first overlay parameter and the second overlay parameter. The first overlay parameter is a parameter related to the overlay error between layers on the wafer on the wafer platform, and the second overlay parameter is another parameter related to the overlay error between the layers on the wafer. The first set of etching parameters is related to an error occurring on both sides of an axis in a first direction perpendicular to the scanning direction in the EUV exposure process, and having an error in the scanning direction that increases proportionally to the cube of the position in the first direction with increasing distance from the axis in the first direction. The second overlay parameter is related to an error in the scanning direction that increases proportionally to the square of the position in the first direction as the distance from the axis in the first direction increases.

2. The EUV exposure apparatus according to claim 1, wherein The correlation includes the ratio between the correction value of the second overlay parameter and the correction value of the first overlay parameter, and The first set of engraving parameters is a parasitic parameter generated due to the correction of the second set of engraving parameters.

3. The EUV exposure apparatus according to claim 2, wherein The correlation is 1:K. K is in the range of -0.25 to -0.45, and The correction value of the first overlay parameter is positive when the absolute value of the overlay error increases in the first and third quadrants according to its position in the first direction, and the correction value of the first overlay parameter is negative when the absolute value of the overlay error increases in the second and fourth quadrants according to its position in the first direction.

4. The EUV exposure apparatus according to claim 1, wherein The correlation is based on the non-telecentric nature of the EUV exposure apparatus and the EUV light incident on the EUV mask in the form of a curved slit, and The correction of the second set of etching parameters is performed by rotating the mask platform about the first direction as an axis.

5. The EUV exposure apparatus of claim 1, wherein the control unit extracts a correction value of the second etch parameter from data relating to the first etch parameter based on the correlation, and controls the rotation of the mask platform based on the correction value of the second etch parameter.

6. The EUV exposure apparatus according to claim 5, wherein the control unit comprises: A mask platform controller, configured to control the mask platform; A wafer platform controller, configured to control the wafer platform; The data acquisition unit is configured to receive the data regarding the first set of etching parameters; The alignment controller is configured to calculate the correction value of the second set of engraving parameters from the data based on the correlation; as well as The feedback unit is configured to transmit the correction value of the second set of etching parameters to the mask platform controller.

7. The EUV exposure apparatus according to claim 1, wherein, When the process allowance for the second set of etching parameters is A, the first set of etching parameters is corrected by adjusting the second set of etching parameters to be within the range of A.

8. An EUV exposure apparatus, comprising: EUV light source; A mask platform configured to hold an EUV mask. as well as The control unit is configured to control the mask platform and correct the first overlay parameter among the overlay error parameters between layers on the wafer by correcting the second overlay parameter. The first set of etching parameters is related to an error occurring on both sides of an axis in a first direction perpendicular to the scanning direction in the EUV exposure process, and having an error in the scanning direction that increases proportionally to the cube of the position in the first direction with increasing distance from the axis in the first direction. The second set of etching parameters is related to an error in the scanning direction that increases proportionally to the square of the position in the first direction as the distance from the axis in the first direction increases.

9. The EUV exposure apparatus of claim 8, wherein the correlation between the correction value of the second set of etching parameters and the correction value of the first set of etching parameters is 1:K, wherein K is in the range of -0.25 to -0.

45.

10. The EUV exposure apparatus according to claim 8, wherein The correction of the second set of etching parameters is performed by rotating the mask platform about the first direction as an axis, and The first overlay parameter, which is a parasitic parameter, is corrected by the rotation of the mask platform.

11. The EUV exposure apparatus of claim 8, wherein the control unit extracts a correction value of the second etch parameter based on data regarding the first etch parameter, and controls the rotation of the mask platform based on the correction value of the second etch parameter.

12. An overlay correction method performed by an EUV exposure apparatus, the overlay correction method comprising: The data obtained by the EUV exposure apparatus are related to a first overlay parameter among the parameters concerning the overlay error between layers on the wafer to which the EUV exposure process is performed. The first overlay parameter is related to an error that occurs on both sides of an axis in a first direction perpendicular to the scanning direction in the EUV exposure process and has a size that increases proportionally to the cube of the position in the first direction as the distance from the axis in the first direction increases. The EUV exposure apparatus calculates a correction value for the second overlay parameter based on the correlation between the first overlay parameter and the overlay error parameter. The second overlay parameter is related to an error in the scanning direction that increases proportionally to the square of the position in the first direction as the distance from the axis in the first direction increases. The correction value of the second set of etching parameters is fed back within the EUV exposure apparatus; as well as Based on the correction value of the second set of parameters, the EUV exposure apparatus corrects the first set of parameters by correcting the second set of parameters.

13. The overlay correction method according to claim 12, wherein... The correlation refers to the ratio between the correction value of the second set of engraving parameters and the correction value of the first set of engraving parameters, and The correlation is 1:K, where K is in the range of -0.25 to -0.

45.

14. The overlay correction method according to claim 12, wherein, When the process allowance for the second set of etching parameters is A, the first set of etching parameters is corrected by adjusting the second set of etching parameters to be within the range of A.

15. A method for manufacturing a semiconductor device using an EUV exposure apparatus, the method comprising: The data obtained by the EUV exposure apparatus are related to a first overlay parameter, which is an error occurring on both sides of an axis in a first direction perpendicular to the scanning direction in the EUV exposure process and has a size that increases proportionally to the cube of the position in the first direction as the distance from the axis in the first direction increases. The EUV exposure apparatus calculates a correction value for the second overlay parameter based on the correlation between the first overlay parameter and the second overlay parameter among the parameters of the overlay error. The second overlay parameter is related to an error in the scanning direction that increases proportionally to the square of the position in the first direction as the distance from the axis in the first direction increases. The correction value of the second set of etching parameters is fed back within the EUV exposure apparatus; The EUV exposure process is performed on the second wafer using the EUV exposure apparatus. Pattern the second chip; as well as Subsequent semiconductor processes are then performed on the second wafer. The EUV exposure process performed on the second wafer includes: correcting the first overlay parameter by correcting the second overlay parameter based on the correction value of the second overlay parameter.

16. The semiconductor device manufacturing method according to claim 15, wherein... The correlation refers to the ratio between the correction value of the second set of etching parameters and the correction value of the first set of etching parameters, and The correlation is 1:K, where K is in the range of -0.25 to -0.

45.

17. The semiconductor device manufacturing method according to claim 15, wherein... The EUV exposure apparatus includes an EUV light source, a mask platform on which an EUV mask is placed, and a control unit configured to control the mask platform. Performing the EUV exposure process on the second wafer includes: The second set of etching parameters is corrected by rotating the mask platform based on the correction value of the second set of etching parameters.

18. The semiconductor device manufacturing method according to claim 17, wherein... The control unit includes a mask platform controller configured to control the mask platform, a data acquisition unit configured to obtain data regarding the first set of engraving parameters, an alignment controller configured to calculate the correction value of the second set of engraving parameters, and a feedback unit configured to transmit the correction value of the second set of engraving parameters to the mask platform controller. The mask platform controller is configured to control the rotation of the mask platform about the first direction as an axis based on the correction value of the second set of etching parameters.

19. The semiconductor device manufacturing method according to claim 15, further comprising: After performing the EUV exposure process on the second wafer, it is determined whether the correction of the first overlay parameters is appropriate for the second wafer. When the correction of the first set of etching parameters is not suitable for the second wafer, the calculation of the correction value of the second set of etching parameters and the execution of the EUV exposure process on another second wafer are repeated.

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