Ellipsometric imaging-based inspection method and method of manufacturing a semiconductor device

Abstract

An inspection method based on ellipsometric imaging (IE) and a method of manufacturing a semiconductor device are provided. The inspection method includes selecting one mode from a first mode having a first field of view (FOV) and a second mode having a second FOV of an IE-based inspection apparatus, measuring an inspection target by the IE-based inspection apparatus based on the selected mode, and determining whether the inspection target is normal based on a measurement result, wherein the measuring the inspection target includes simultaneously measuring patterns included in a plurality of cells provided in a region of the inspection target, the region corresponding to the FOV of the selected mode.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to Korean Patent Application No. 10-2019-0088525, filed on July 22, 2019, with the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference. Technical Field

[0003] The exemplary embodiments of this disclosure relate to an inspection apparatus and inspection method, and more specifically, to an inspection apparatus and inspection method based on ellipsometric imaging. Background Technology

[0004] Ellipsometry is an optical technique for studying the dielectric properties of wafers. Ellipsometry calculates information about a sample by analyzing the polarization changes of reflected light from the sample (e.g., the wafer surface). For example, when light is reflected by the sample, the polarization state of the reflected light varies depending on the optical properties of the sample material, the thickness of the sample layer, etc. By measuring these polarization changes, ellipsometry can calculate the complex refractive index or dielectric tensor, which are fundamental physical quantities of the material, and can also derive information about the sample, such as the material's shape, crystallinity, chemical structure, and electrical conductivity. Furthermore, ellipsometry imaging (IE) and spectral ellipsometry imaging (SIE) are types of ellipsometry that use broadband light sources. Summary of the Invention

[0005] One or more example embodiments provide an ellipsometric imaging (IE)-based inspection method that allows for more accurate measurement of measurement keys on a wafer in a large-area and high-rate manner, and a method for manufacturing a semiconductor device using the IE-based inspection method.

[0006] According to one aspect of an example embodiment, an ellipsometry (IE)-based inspection method is provided, the method comprising: selecting a mode from a first mode of an IE-based inspection apparatus having a first field of view (FOV) and a second mode having a second FOV; measuring an inspection target through the IE-based inspection apparatus based on the selected mode; and determining whether the inspection target is normal based on the measurement result, wherein measuring the inspection target includes simultaneously measuring a pattern included in a plurality of cells disposed in a region of the inspection target, the region corresponding to the FOV of the selected mode.

[0007] According to another aspect of an example embodiment, an ellipsometry (IE)-based inspection method is provided, the method comprising: obtaining two-dimensional (2D) images of patterns included in a plurality of units of an inspection target at each wavelength using an IE-based inspection apparatus; extracting intensity data of each wavelength from the two-dimensional images of each wavelength; comparing the intensity data of each wavelength with reference data; and determining whether the overlay of the inspection target is normal based on the comparison result; wherein obtaining the 2D images at each wavelength includes simultaneously measuring the patterns included in the plurality of units.

[0008] According to another aspect of an example embodiment, a method for manufacturing a semiconductor device is provided, the method comprising: selecting a mode from a first mode of an ellipsometric imaging (IE)-based inspection apparatus having a first field of view (FOV) and a second mode of an IE-based inspection apparatus having a second FOV; measuring a wafer through the IE-based inspection apparatus in the selected mode; determining whether the wafer is normal based on the measurement result; and performing a semiconductor process on the wafer based on the determination that the wafer is normal, wherein measuring the wafer includes simultaneously measuring a pattern included in a plurality of cells disposed in a region of the wafer, the region corresponding to the FOV of the selected mode. Attached Figure Description

[0009] The above and / or other aspects, features, and advantages will become clearer from the following detailed description of exemplary embodiments in conjunction with the accompanying drawings, in which:

[0010] Figure 1 This is a schematic structural diagram of an ellipsometry-based (IE) inspection apparatus according to an example embodiment;

[0011] Figure 2 This is a conceptual diagram showing the arrangement of measurement keys on a wafer, which are achieved by using... Figure 1 It is measured using an IE-based inspection device;

[0012] Figure 3A and Figure 3B It is shown by using Figure 1 A conceptual diagram of a method for measuring measurement keys on a chip using an IE-based inspection device;

[0013] Figure 4A and Figure 4B It is shown by using Figure 1 A conceptual diagram illustrating the principle of using an IE-based inspection device to measure overlay keys and focus keys formed on a wafer, respectively.

[0014] Figures 5A to 5DThis illustrates that, according to an example embodiment, it is designed to have a high density in order to... Figure 1 A top view of the shape of the measuring keys used in conjunction with an IE-based inspection device;

[0015] Figure 6A and Figure 6B It shows the use Figure 1 A conceptual diagram and its effect of unit overlay measurement performed by an IE-based inspection device;

[0016] Figure 7 This is a schematic diagram illustrating the structure of an IE-based inspection device according to an example embodiment;

[0017] Figures 8A to 8C These are flowcharts illustrating the IE-based inspection method according to the example embodiments; and

[0018] Figure 9A and Figure 9B These are flowcharts illustrating methods for manufacturing semiconductor devices using an IE-based inspection method according to example embodiments. Detailed Implementation

[0019] In the following description, exemplary embodiments will be described in detail with reference to the accompanying drawings. Throughout the specification, the same parts will be indicated by the same reference numerals, and repeated descriptions of them will be omitted.

[0020] As used herein, expressions such as “in front of,” “in front of,” or “before,” “behind,” “behind,” or “after” can indicate the relative position of light propagation with respect to the respective component. For example, when light passes through a lens and then through a particular component, the lens can be positioned in front of that particular component. When light passes through a particular component first and then through the lens, the lens can be positioned behind that particular component.

[0021] Figure 1 This is a schematic diagram illustrating the structure of an ellipsometry-based (IE) inspection apparatus according to an example embodiment.

[0022] Reference Figure 1The IE-based inspection apparatus 100 in the example embodiment can be an ellipsometric imaging (IE) based inspection apparatus. Here, IE can include spectral ellipsometric imaging (SIE). For reference, ellipsometrics is a method for measuring the optical fine structure of a single or multilayer thin film on a sample by analyzing the change in polarization state when incident light is reflected by the sample. Because ellipsometrics utilizes the reflection of light, it does not require specific measurement conditions such as a vacuum. In addition, spectral ellipsometrics, which includes additional spectral functions, measures and analyzes the inspection target based on a large amount of information measured at several wavelengths, thus improving the reliability of the analysis. The method of measuring and analyzing the inspection target by obtaining a two-dimensional (2D) image through a detector such as a charge-coupled device (CCD) camera based on the above-described ellipsometrics or spectral ellipsometrics is called ellipsometric imaging (IE) or spectral ellipsometric imaging (SIE).

[0023] The inspection apparatus 100 of the example embodiment may include a vertical optical system Vop, a tilting optical system Top, and a platform 155. Figure 1 In the diagram, the vertical optical system Vop and the tilt optical system Top are marked by dashed lines, and the vertical optical system Vop and the tilt optical system Top may also include a light source 110 and a monochromator 120.

[0024] The vertical optical system Vop may include a light source 110, a monochromator 120, a first collimator 130-1, a first polarizer 140-1, a beam splitter 150, an objective lens 160, a first analyzer 170-1, a first imaging lens unit 180-1, and a first detector 190-1.

[0025] In an optical inspection apparatus, the optical system includes an illumination optical system and an imaging optical system. Typically, the illumination optical system can be an optical system along the path from the light source 110 to the inspection target 200, and the imaging optical system can be an optical system along the path from the inspection target 200 to the detector. For example, in a vertical optical system (Vop), the illumination optical system may include a first collimator 130-1, a first polarizer 140-1, and a beam splitter 150, while the imaging optical system may include an objective lens 160, a first analyzer 170-1, and a first imaging lens unit 180-1. Furthermore, in a tilting optical system (Top), the illumination optical system may include a second collimator 130-2 and a second polarizer 140-2, while the imaging optical system may include a second analyzer 170-2 and a second imaging lens unit 180-2.

[0026] Light source 110 can be a broadband light source or a multi-wavelength light source that generates and outputs broadband light. The broadband light from light source 110 can be multi-color light including light with multiple wavelength bands. For example, in the inspection apparatus 100 of the example embodiment, light source 110 can generate and output light with a wavelength range of 150 nm to 2100 nm. However, the wavelength range of the light generated by light source 110 is not limited to the above range. For example, light source 110 can be a halogen lamp light source or a light-emitting diode (LED) light source that generates continuous spectrum light. However, the type of light source 110 is not limited to this. In the inspection apparatus 100 of the example embodiment, various spectra can be configured by implementing light source 110 as a broadband light source.

[0027] Monochromator 120 can convert broadband light from light source 110 into monochromatic light and output monochromatic light. Here, monochromatic light can be light with a very small wavelength width. For example, monochromatic light can be light with a wavelength width of about a few nanometers. Monochromator 120 can output multiple beams of monochromatic light while performing a scan on a wavelength width set within a specific wavelength range. Monochromator 120 may include a grating or prism that can divide the incident light by wavelength.

[0028] The first collimator 130-1 can convert monochromatic light received from the monochromator 120 into parallel light and output parallel light. Light can be transmitted from the light source 110 to the monochromator 120 via the first optical fiber F1, and light can be transmitted from the monochromator 120 to the first collimator 130-1 via the second optical fiber F2. However, the transmission of light is not limited to transmission via optical fibers.

[0029] The first polarizer 140-1 can polarize light received from the first collimator 130-1 and output polarized light. Polarization can include, for example, at least one selected from the group consisting of linear polarization, circular polarization, and elliptic polarization. Here, linear polarization can refer to converting incident light into linearly polarized light by allowing only the p-polarized component (or horizontal component) or s-polarized component (or vertical component) of the incident light to pass through. Alternatively, circular polarization or elliptic polarization can refer to converting linearly polarized light into circularly or ellipticly polarized light, or vice versa, by applying a phase shift to linearly polarized light. Therefore, the polarizer performing circular or elliptic polarization can also be a phase delayer.

[0030] Beam splitter 150 can output light received from first polarizer 140-1 to inspection target 200, and can output reflected light, which is reflected by inspection target 200, toward first detector 190-1. For example, beam splitter 150 can output light received from first polarizer 140-1 to inspection target 200 by transmitting or reflecting light from first polarizer 140-1, and can output reflected light from inspection target 200 toward first detector 190-1 by reflecting or transmitting reflected light.

[0031] Objective lens 160 can converge the light received from beam splitter 150 and output the converged light towards inspection target 200. In addition, objective lens 160 can output reflected light (light reflected by inspection target 200) to beam splitter 150.

[0032] The first analyzer 170-1 can be arranged behind the beam splitter 150, between the beam splitter 150 and the first imaging lens unit 180-1, and can selectively allow reflected light reflected by the inspection target 200 to pass through, thus giving the reflected light a changed polarization direction. For example, the first analyzer 170-1 can allow only a specific polarization component of the incident light to pass through, and can block the remaining components of the incident light. According to an example embodiment, the first analyzer 170-1 can be arranged behind the first imaging lens unit 180-1, between the first detector 190-1 and the first imaging lens unit 180-1.

[0033] The first imaging lens unit 180-1 may include at least one lens for imaging. For example, the first imaging lens unit 180-1 may include an imaging barrel lens. The first imaging lens unit 180-1 may output light reflected by the inspection target 200 to the first detector 190-1, thereby imaging the inspection target 200 onto the first detector 190-1. At least a portion of the inspection target 200 corresponding to the field of view (FOV) can be imaged onto the first detector 190-1 via the first imaging lens unit 180-1.

[0034] The first detector 190-1 can generate a 2D image of the target 200. For example, the first detector 190-1 can receive light reflected from the target 200 via the first imaging lens unit 180-1, thereby imaging the target 200 onto an imaging plane. As described above, the 2D image of the target 200 can be a 2D image corresponding to the field of view (FOV) of the first detector 190-1. The first detector 190-1 can be, for example, a CCD camera. However, the first detector 190-1 is not limited to a CCD camera.

[0035] The first detector 190-1 can generate multiple 2D images of the inspection target 200 corresponding to multiple wavelengths. For example, in the inspection apparatus 100 of the example embodiment, the light source 110 can generate and output broadband light, and the monochromator 120 can divide the broadband light into light rays each having multiple wavelengths, and sequentially output these light rays to the inspection target 200. Therefore, the first detector 190-1 can generate multiple 2D images of the inspection target 200 corresponding to each wavelength.

[0036] In the inspection apparatus 100 of this example embodiment, the first detector 190-1 can be a detector with high resolution. For example, the first detector 190-1 can have a pixel size of 500nm or smaller and a pixel size of 400×400μm. 2 Or a larger FOV. However, the pixel size and FOV of the first detector 190-1 are not limited to the values ​​mentioned above. The first detector 190-1 can have extremely high resolution due to its fine pixel size. For example, the first detector 190-1 can have a pixel size of 500 nm or smaller.

[0037] According to the inspection apparatus 100 of this example embodiment, the first detector 190-1 can be implemented with high resolution based on the vertical optical system Vop, and thus allow inspection of targets 200 such as Figure 2 The measurement keys or measurement marks shown are finer and denser to improve simultaneous measurement and / or measurement throughput. Additionally, since the first detector 190-1 may have a very small or almost no spot size, signal distortion caused by the mismatch between the spot size and the measurement key size, and the resulting reduction in measurement consistency, can be improved. (Refer to...) Figures 5A to 5D A more detailed description of the manufacturing of measuring keys with finer dimensions and higher density.

[0038] The tilting optical system Top may include a light source 110, a monochromator 120, a second collimator 130-2, a second polarizer 140-2, a second analyzer 170-2, a second imaging lens unit 180-2, and a second detector 190-2.

[0039] As described above, the vertical optical system Vop and the tilt optical system Top can share the light source 110 and the monochromator 120, and the operation of the light source 110 and the monochromator 120 can be substantially the same between the vertical optical system Vop and the tilt optical system Top.

[0040] The second collimator 130-2, the second polarizer 140-2, and the second analyzer 170-2 may be arranged differently from the first collimator 130-1, the first polarizer 140-1, and the first analyzer 170-1, but they can perform essentially the same operations as the first collimator 130-1, the first polarizer 140-1, and the first analyzer 170-1. For example, as Figure 1As shown, the second collimator 130-2 and the second polarizer 140-2 can be arranged along a light propagation path through which monochromatic light is output from the monochromator 120 at an angle to the inspection target 200. The second analyzer 170-2 can be arranged along a light propagation path through which light reflected from the inspection target 200 is emitted at an angle toward the second detector 190-2. Here, the angle of inclination can be defined relative to the top surface of the inspection target 200 or relative to a direction perpendicular to the top surface of the inspection target 200. The second collimator 130-2 can convert the monochromatic light received from the monochromator 120 into parallel light and output the parallel light. The second polarizer 140-2 can polarize the light received from the second collimator 130-2 and output polarized light. The second analyzer 170-2 can selectively allow reflected light reflected from the inspection target 200 to pass through, thus giving the reflected light a changed polarization direction.

[0041] The second imaging lens unit 180-2 may include at least one lens for imaging. For example, the second imaging lens unit 180-2 may include an imaging tube lens. The second imaging lens unit 180-2 can image the inspection target 200 onto the second detector 190-2. Not the entire inspection target 200, but only the portion of the inspection target 200 corresponding to the field of view (FOV) can be imaged onto the second detector 190-2 via the second imaging lens unit 180-2.

[0042] The second detector 190-2 can generate a 2D image of the target 200. For example, the second detector 190-2 can receive light reflected from the target 200 via the second imaging lens unit 180-2, thereby imaging the target 200 onto an imaging plane. Similar to the first detector 190-1, the second detector 190-2 can generate multiple 2D images of the target 200 corresponding to multiple wavelengths. The second detector 190-2 can also be, for example, a CCD camera. However, the second detector 190-2 is not limited to a CCD camera.

[0043] In the inspection apparatus 100 of the example embodiment, the second detector 190-2 can detect images with relatively high resolution and detect large areas. For example, the second detector 190-2 can have a pixel size of 10 μm or smaller and a resolution of up to 9 × 9 mm. 2 The field of view (FOV) is large. Therefore, the second detector 190-2 can measure and examine the portion of the target 200 corresponding to the large FOV at high resolution by performing a single imaging operation. For example, the second detector 190-2 can have a pixel size of about 5 μm to about 10 μm and an 8×5 mm... 2The FOV (Field of View) is used to obtain a 2D image of the inspected target 200. Therefore, the second detector 190-2 can measure the inspected target 200 at a high rate in planar units based on the large FOV.

[0044] For reference, when the first detector 190-1 is approximately compared with the second detector 190-2 in terms of resolution and field of view (FOV), the resolution of the first detector 190-1 can be 10 times or more than that of the second detector 190-2. Furthermore, the FOV of the second detector 190-2 can be 100 times or more than that of the first detector 190-1. However, the relative magnitudes of each of the resolutions and FOVs between the first detector 190-1 and the second detector 190-2 are not limited to the values ​​described above.

[0045] In the inspection apparatus 100 of the example embodiment, because the second detector 190-2 is implemented with a large field of view (FOV) based on a tilted optical system, it is possible to simultaneously measure the measurement keys included in the portion of the inspection target 200 corresponding to the FOV. Therefore, the rate of measuring the measurement keys of the inspection target 200 can be significantly improved. (Refer to...) Figure 2 The measurement keys formed on the inspection target 200 and the large-area / high-rate measurements performed by the second detector 190-2 are described in more detail.

[0046] The inspection target 200 can be arranged on the platform 155. The platform 155 can move the inspection target 200 by linear motion in the x, y, and z directions. Therefore, the platform 155 can be an xyz platform. According to an example embodiment, the platform 155 can move the inspection target 200 by linear and / or rotational motion.

[0047] Here, the inspection target 200 may include various devices to be inspected, such as wafers, semiconductor packages, semiconductor chips, display panels, etc. For example, in the inspection apparatus 100 of the example embodiment, the inspection target 200 may be a wafer including multiple semiconductor chips. Additionally, multiple measurement keys for photolithography process control may be formed on the wafer serving as the inspection target 200. For example, the multiple measurement keys may include overlay keys, focus keys, dose keys, critical dimension (CD) keys, etc.

[0048] Both the vertical optical system Vop and the tilt optical system Top may also include optical components other than those described above. For example, the vertical optical system Vop may also include a shutter, a neutral density (ND) filter, at least one mirror, a focusing lens, etc., in its illumination optical system section. Similarly, the tilt optical system Top may include a shutter and an ND filter in its illumination optical system section, and at least one folding mirror in its imaging optical system section.

[0049] The inspection apparatus 100 of the example embodiment may include a high-resolution mode vertical optical system Vop and a large-area mode tilted optical system Top. Therefore, based on the vertical optical system Vop, the inspection apparatus 100 of the example embodiment can allow for finer and denser measurement keys in the inspected target 200, and can improve the simultaneous measurement of measurement keys and / or measurement throughput.

[0050] The inspection apparatus 100 of the example embodiment can measure the inspection target 200 at a relatively high rate on a planar basis by measuring the inspection target 200 with high resolution and a large FOV based on the tilted optical system Top. Furthermore, the overlay between measurement keys (e.g., overlay keys) in the scribe line and the overlay between patterns in the cells are measured simultaneously, thereby obtaining the locality of overlay within the exposure area (in-shot) according to process variations, and obtaining higher accuracy data by removing or reducing noise due to averaging effects. (See reference...) Figure 6A and Figure 6B A more detailed description of the measurements and effects of on-cell overlay.

[0051] The inspection apparatus 100 of the example embodiment can reduce or minimize the spot size based on a relatively high resolution, and thus can improve signal distortion caused by the mismatch between the spot size and the size of the measurement key, as well as the reduction in measurement consistency caused by the signal distortion.

[0052] The inspection apparatus 100 of the example embodiment can measure and inspect precise and high-resolution measurement keys formed on the inspection target 200 at a large area and high rate using a vertical optical system (Vop) in high-resolution mode and a tilted optical system (Top) in large-area mode, thereby detecting errors in semiconductor processes (e.g., photolithography). Additionally, the inspection apparatus 100 of the example embodiment can provide feedback data about the measurement keys obtained through measurement, allowing this data to be used as reference data in the photolithography process or for calibration of reference data. Furthermore, the photolithography process can be controlled more effectively by using the reference data obtained in this way.

[0053] Figure 2 This is a conceptual diagram showing the arrangement of measurement keys on a wafer, which are achieved by using... Figure 1 It is measured using an IE-based inspection device.

[0054] Reference Figure 2 The image on the far left shows a wafer as the inspection target 200, and multiple exposure areas (shots) divided by straight lines are shown on the wafer. An exposure area can be an area on the wafer where a pattern on a mask is transferred to the wafer by performing exposure in a photolithography process, or an area on the wafer corresponding to that pattern.

[0055] like Figure 2 As shown, the magnified exposure area illustrates that an exposure area can include multiple chips. For example, Figure 2 An exposure area can include up to 18 chips. However, the number of chips included in an exposure area is not limited to this. For example, depending on the type of chip, the exposure area can include one chip or various numbers of chips.

[0056] like Figure 2 As shown in the magnified image, a chip (e.g., a memory chip such as DRAM) can have a structure in which multiple memory banks are arranged on both sides of a scribe line arranged in a central region. A memory bank can be a collection of multiple cells, and the scribe line can be arranged between the memory banks. The scribe line is typically, but not limited to, a region used for dicing. The scribe line can be a region other than the memory bank region where cells are arranged.

[0057] A portion of the chip is magnified and displayed on the far right, together with a portion of the memory cell C and the scribe line SL. (See image.) Figure 2 As shown, measurement keys can be arranged in the scribe line SL. Measurement keys can include, for example, overlay keys OVL, focus keys F, dose keys D, CD keys OCD, etc. Although the measurement keys are shown as quadrilaterals, each measurement key can include a pattern with a complex structure, such as... Figure 3A As shown. Furthermore, although the measuring keys are arranged in a row in the dicing track SL, the arrangement of the measuring keys is not limited to this. For example, the measuring keys can be arranged in various positions within the dicing track SL. Additionally, the measuring keys can be arranged both within the cells and in the dicing track SL.

[0058] Figure 3A and Figure 3B It is shown by using Figure 1 A conceptual diagram of a method for measuring measurement keys on a wafer using an IE-based inspection device. (Refer to...) Figure 3A and Figure 3B and Figure 1 Describe them together, and provide a brief description or omit references. Figure 1 and Figure 2 The given description is repetitive.

[0059] Reference Figure 3A Four memory cells can be arranged on each side of a scribe line in the central region of a chip. However, the number of memory cells in a chip is not limited to this. Figure 3A The eight shown are examples. Multiple measurement keys can be arranged in the dicing track. Alternatively, the measurement keys can also be arranged between memory cells.

[0060] Measurement keys (e.g., overlay key OVL, focus key F, and dose key D) are magnified and shown in Figure 3A In this process, each measurement key is typically formed to a size of approximately 30 μm. Existing inspection devices can measure each key using a point measurement method. In this point measurement method, the inspection device's light spot needs to be completely included within the measurement key to achieve high measurement consistency. When the inspection device's light spot is partially off-center from the measurement key, signal distortion may occur due to the inclusion of the edge portion of the measurement key, potentially reducing measurement consistency.

[0061] Recently, as processes for manufacturing increasingly finer-sized semiconductor structures continue, higher bond density and faster bond measurement rates are required to handle these finer-size processes, leading to a reduction in bond size. This reduction in bond size may necessitate a decrease in the spot size of the optical system used for bond measurement. However, this can result in problems such as reduced measurement throughput and decreased measurement consistency due to signal distortion caused by mismatch between spot size and bond size.

[0062] The inspection apparatus 100 of the example embodiment can accurately measure the inspection target 200 at high speed with high resolution and a large field of view (FOV) by using a tilted optical system Top. As described above, in the inspection apparatus 100 of the example embodiment, the second detector 190-2 of the tilted optical system Top can have a pixel size of 10 μm or smaller and a maximum size of about 9 × 9 mm. 2 The field of view (FOV). When the chip has a first length L1 of 8 mm and a first width W1 of 5 mm, the second detector 190-2 can obtain a 2D image of the entire chip by performing a single imaging operation, such as... Figure 3A As shown, all the measurement keys arranged in the chip can be measured simultaneously.

[0063] As a specific example, when the measurement keys have a size of 30 μm, 200 or more measurement keys can be arranged in a direction corresponding to a length of 8 mm. Therefore, the inspection apparatus 100 of the example embodiment can simultaneously measure 200 or more measurement keys using the second detector 190-2. Furthermore, hundreds of measurement keys can typically be formed within an exposure area. For example, each of the overlay key (OVL), focus key (F), and dose key (D) can be formed in numbers of 100 or more within an exposure area. According to point measurement type inspection apparatuses of the related art, a significant amount of time is required to measure all measurement keys; therefore, sampling can be used to measure only the measurement keys in a limited area. However, errors in sampling and the resulting distortion of measurement information may be unavoidable. On the other hand, considering the FOV of the second detector 190-2 and based on the size of the exposure area being approximately 12 × FOV, the inspection apparatus 100 of the example embodiment can measure all measurement keys included in the exposure area by performing 12 imaging operations. Therefore, the problem of measurement distortion caused by measuring only the measurement keys in a limited area through sampling can be improved.

[0064] Reference Figure 3B In the inspection apparatus 100 of the example embodiment, both the vertical optical system Vop and the tilt optical system Top can perform inspection based on SIE. For example, images of the inspection target 200 at various wavelengths can be obtained, and information about the corresponding measurement key can be obtained by mapping each image to characteristic values ​​based on the wavelength.

[0065] As a specific example, such as Figure 3B As shown, multiple images at various wavelengths can be obtained for a single chip, and the intensity I of each wavelength can be extracted for the measurement key (e.g., overlay key OVL), thereby obtaining, as shown... Figure 3B The graph shown is an example of a curve. Next, the consistency of the overlay bonding for the corresponding chip can be determined by comparing the obtained curve with a reference curve stored in a database (DB). When there is no reference curve in the DB, a reference curve can be derived using deep learning by using curves obtained from multiple chips as source data, and consistency can also be determined by comparing the obtained curve with the derived reference curve.

[0066] While the above example illustrates extracting the intensity I of each wavelength as measured data, the measured data is not limited to the intensity I of each wavelength. For example, Psi(ψ) and / or wavelength-Delta(δ) of each wavelength can be extracted as measured data. Here, Psi(ψ) can represent the ratio of P-wave to S-wave, while Delta(δ) can represent the phase difference between P-wave and S-wave.

[0067] Figure 4A and Figure 4B It is shown by using Figure 1 A conceptual diagram illustrating the principle of an IE-based inspection device for measuring overlay bonds and focus bonds formed on a wafer, respectively. (Refer to...) Figure 4A and Figure 4B and Figure 1 and Figure 2 Describe them together, and provide a brief description or omit references. Figures 1 to 3B The given description is repetitive.

[0068] Reference Figure 4A OVL keys can be keys used for alignment between lower and upper layers. For example, the alignment between upper and lower layers can be checked by measuring the positional error between the first OVL1 key on the lower layer and the second OVL2 key on the upper layer.

[0069] The inspection apparatus 100 of the example embodiment can inspect the alignment status between the upper and lower layers by extracting the intensity of each wavelength with respect to the first set of key OVL1 and the second set of key OVL2 based on SIE. For example, when the intensity of each wavelength has a shape as shown by the solid line while the first set of key OVL1 and the second set of key OVL2 are aligned, when the second set of key OVL2 moves to the left and is misaligned, the intensity of each wavelength can be extracted as a curve as shown by the dashed line ①, and when the second set of key OVL2 moves to the right and is therefore misaligned, the intensity of each wavelength can be extracted as a curve as shown by the single-dot dashed line ②. Therefore, according to the inspection apparatus 100 of the example embodiment, a 2D image at each wavelength can be obtained, and a curve depicting the intensity of each wavelength can be extracted for the corresponding key set and compared with a reference curve (e.g., Figure 4A The alignment between the upper and lower layers can be checked by comparing the curves marked with solid lines.

[0070] Reference Figure 4B The focus bond F can be a bond used to check the focus state during the photolithography process. Typically, a pattern corresponding to the focus bond F can be formed on a mask, and the focus bond F can be formed on the substrate by transferring the corresponding pattern through photolithography.

[0071] Figure 4B The diagram shows focus keys RF2 and SF2 when the defocus is 0, focus keys RF1 and SF1 when the defocus is negative (-), and focus keys RF3 and SF3 when the defocus is positive (+). Depending on the defocus state, the positions of the right focus keys SF1, SF2, and SF3 may change because the portions of the mask corresponding to the right focus keys SF1, SF2, and SF3 are formed using a phase-shifting structure.

[0072] The inspection apparatus 100 of the example embodiment can inspect the focus state by extracting the intensity of each wavelength with respect to the focus key based on SIE. For example, when the defocus is 0 as shown in (c), the intensity of each wavelength can be extracted as a curve shown by the solid line in (a); when the defocus is negative (-), the intensity of each wavelength can be extracted as a curve shown by the single-dot dashed line in (a); and when the defocus is (+), the intensity of each wavelength can be extracted as a curve shown by the dashed line in (a). Therefore, according to the inspection apparatus 100 of the example embodiment, a 2D image at each wavelength can be obtained, and a curve depicting the intensity of each wavelength can be extracted for the corresponding focus key and compared with a reference curve (e.g., by...). Figure 4B The focus status is checked by comparing the curve marked with the solid line in (a).

[0073] The principle of measuring the dose bond D can be similar to that of the focus bond F. For example, in a photolithography process, the shape of the dose bond can vary depending on the dose, and therefore the intensity at each wavelength may differ. Thus, the inspection apparatus 100 of the example embodiment can obtain a 2D image at each wavelength, extract a graph depicting the intensity at each wavelength with respect to the corresponding dose bond, and compare this graph with a reference graph to inspect the dose status.

[0074] Figures 5A to 5D This illustrates that, according to an example embodiment, it is designed to have a high density in order to... Figure 1 A top view of the shape of the measuring key used with the IE-based inspection device. (Refer to...) Figures 5A to 5D and Figure 1 Describe them together, and include brief descriptions or omissions with references. Figures 1 to 4B The given description is repetitive.

[0075] Reference Figure 5A The focus bond F, dose bond D, and overlay bond OVL formed on the scribe line SL are magnified and shown. Figure 5A In this context, each of the focus bond F, dose bond D, and overlay bond OVL can be formed to have a size greater than or equal to 30 μm. Here, the 30 μm size can be the length of each side of a square. However, the shape of each of the focus bond F, dose bond D, and overlay bond OVL is not limited to a square and can have various shapes.

[0076] When formed to a size greater than or equal to 30 μm, focus bonds (F), dose bonds (D), and overlay bonds (OVL) may be unsuitable for finer-size processes and would occupy a significant amount of space. Therefore, it may be difficult to form each of these bonds at appropriate locations within the chip, or each of these bonds may limit the space utilization of the cells. However, in related technology inspection apparatuses, due to limitations in spot size, it is difficult to reduce the size of the measurement bonds to 30 μm or smaller.

[0077] On the other hand, in the inspection apparatus 100 according to the example embodiment, in the vertical optical system Vop with high resolution, because the first detector 190-1 has a pixel size of 500 nm or less and a corresponding resolution, the size of the measured key can be reduced to 30 μm or less. Figures 5B to 5D The image shows, as an example, measuring keys of various shapes with reduced dimensions.

[0078] Reference Figure 5B The two focusing keys F1 and F2, one dosing key D, and one overlay key OVL can be formed together in a 2×2 array structure, with each key having a size of 15 μm. Because the four measurement keys F1, F2, D, and OVL are formed together in a 2×2 array structure, the total size of the four measurement keys can be 30 μm. In the inspection apparatus 100 of the example embodiment, based on the use of the vertical optical system Vop with high resolution, the measurement problem described above can be improved even if each of the measurement keys F1, F2, D, and OVL is reduced to a size of 30 μm or less.

[0079] like Figure 5B As shown, the two focusing keys F1 and F2 can have different shapes and orientations. Therefore, the focusing state can be checked more accurately. Furthermore, when multiple focusing keys (e.g., focusing keys F1 and F2) are used together with the dose key D, measurement consistency can be improved because the correlation between the dose key D and focusing keys F1 or F2 is minimized. Compared to the 30 μm size measurement keys in related technologies, measurement keys F1, F2, D, and OVL can be densified by 4 times. Therefore, measurement keys F1, F2, D, and OVL can improve simultaneous measurement and measurement throughput.

[0080] Reference Figure 5CThe four focusing bonds F1 to F4 can be formed together in a 2×2 array structure, with each focusing bond having a size of 15 μm. The four focusing bonds F1 to F4 as a group can have a total size of 30 μm. The four focusing bonds F1 to F4 can have different shapes and orientations. Therefore, the focusing state can be measured more accurately. Although focusing bond F is used as an example, the embodiments are not limited to this. For example, four dose bonds D can be formed together in a 2×2 array structure, with each dose bond having a size of 15 μm.

[0081] Reference Figure 5D The six focusing keys F1 to F6, two dosing keys D1 and D2, and one overlay key OVL can be formed together in a 3×3 array structure, with each key having a size of 10 μm. The nine measurement keys F1 to F6, D1, D2, and OVL as a group can have a total size of 30 μm. In the inspection apparatus 100 of the example embodiment, because a high-resolution vertical optical system Vop is used, measurement problems can be improved even when each of the measurement keys F1 to F6, D1, D2, and OVL is formed to a size of 30 μm or smaller.

[0082] exist Figure 5D In this study, using six focusing keys F1 to F6 allows for more precise measurement of the focusing state, and using two dose keys D1 and D2 allows for more precise measurement of the dose state. The density of measurement keys F1 to F6, D1, D2, and OVL can be up to nine times that of existing 30μm-sized measurement keys. Therefore, measurement keys F1 to F6, D1, D2, and OVL can further improve simultaneous measurement and measurement throughput.

[0083] exist Figure 5B The arrangement of the four measurement keys F1, F2, D, and OVL in the 2×2 array structure and in Figure 5D The arrangement of the nine measurement keys F1 to F6, D1, D2, and OVL in the 3×3 array structure is not limited to those shown and can be varied. For example, the arrangement of the measurement keys (e.g., F, D, and OVL) can be adjusted according to the importance of the measurement, thereby maximizing the amount of information and improving measurement accuracy.

[0084] Although it has been referenced Figure 5B , Figure 5C and Figure 5D The description describes a structure in which each of the measurement keys F, D, and OVL is formed with a size of 15 μm or 10 μm, but the size of each of the measurement keys F, D, and OVL is not limited thereto. For example, according to an example embodiment, each of the measurement keys F, D, and OVL can be formed with a size of less than 10 μm.

[0085] Figure 6A and Figure 6B It shows the use Figure 1 A conceptual diagram and its effect of unit overlay measurement performed by an IE-based inspection device. (Refer to...) Figure 6A and Figure 6B and Figure 1 Describe them together, or omit references in a brief description. Figures 1 to 4B The given description is repetitive.

[0086] Reference Figure 6A This illustrates the concept of measuring overlay in a cell C. More specifically, although overlay measurements in related technologies target the overlay key OVL in the scribe line SL outside cell C, recent advancements have necessitated direct overlay measurements between patterns within cell C. In the case of inspection apparatuses in related technologies, due to spot size limitations of 30 μm or larger and measurement rate limitations, only a very small number of cells can be measured through sampling. For example, in... Figure 6A In this process, only one of the 25 units C can be selected and measured as an overlay. Figure 6A The enlarged view shows the measurement between the circular hole below and the line extending over the hole.

[0087] Thus, when sampling and measuring several units C, it is difficult to obtain the positional characteristics of the overlay according to process variations. Here, positional characteristics can refer to the trend exhibited at each position. For example, according to inspection devices in related technologies, for overlay between patterns, only the overlay keys formed in the dicing track are measured, or only specific units are selected and measured, thus failing to ensure the trend of overlay at each position according to process variations, i.e., the positional characteristics of the overlay.

[0088] In an example embodiment, the inspection target 200 may be a wafer comprising a plurality of semiconductor chips, and the overlay at each location of the wafer is determined by averaging overlay values ​​measured over the entire area of ​​the wafer. Alternatively, the inspection target 200 may be a semiconductor chip, and the overlay at each location of the semiconductor chip is determined by averaging overlay values ​​measured over the entire area of ​​the semiconductor chip.

[0089] Reference Figure 6B In the inspection apparatus 100 of the example embodiment, 2D images of all units C (e.g., 25 units C) at each wavelength can be obtained by using a large-area type tilting optical system Top. Furthermore, from the 2D images at each wavelength, the intensity I of each wavelength can be extracted for each unit involved in the overlay. Figure 6B The graph in the image shows the intensity I for each wavelength of the 25 units C. Figure 6B In the example, arrows indicate 12 curves corresponding to 12 units C.

[0090] In this way, the overlay is measured on all units, thereby allowing the measurement of the overlay trend at each location according to process variations. For example, in the inspection apparatus 100 of the example embodiment, the positional characteristics of the overlay according to process variations can be obtained by measuring the overlay on all units using a tilting optical system Top. Furthermore, when overlay is measured on all units, more accurate overlay information can be obtained because noise caused by randomness is canceled out by each other due to the averaging effect.

[0091] Furthermore, according to the inspection apparatus 100 of the example embodiment, the intensity I of each wavelength related to overlay can be extracted at a high rate for each cell of the entire wafer using a large-area type tilted optical system. Therefore, an overlay pattern of the entire wafer can be obtained. Here, as described above, it may be necessary to pre-store reference data about the normal state to determine the overlay state, and then the overlay state can be determined by comparing the obtained overlay pattern with the reference data.

[0092] When no reference data is prepared in advance, deep learning can be performed using data on the intensity I of each wavelength as the basic data for deep learning, thereby deriving reference data. In the case of inspection apparatuses of related technologies, it is difficult to perform deep learning and even if deep learning is performed, it is difficult to obtain accurate results because data only exists for a specific region (e.g., scribe line SL) or only for a few cells is sampled. In contrast, the inspection apparatus 100 according to the example embodiment, based on a large-area type tilting optical system Top, can ensure a large amount of data for cells of the entire wafer, thereby making it easier to perform deep learning and the results can be more accurate.

[0093] Figure 7 This is a schematic diagram illustrating the structure of an IE-based inspection device according to an example embodiment. References will be briefly described or omitted. Figures 1 to 6B The given description is repetitive.

[0094] Reference Figure 7 The inspection device 100a of the example embodiment and Figure 1The inspection apparatus 100 may differ in that the vertical optical system Vop' and the tilt optical system Top' in the inspection apparatus 100a are configured separately from each other. For example, in the inspection apparatus 100a of the example embodiment, the vertical optical system Vop' and the tilt optical system may each include a respective light source and a respective monochromator. For example, the vertical optical system Vop' may include a first light source 110-1, a first monochromator 120-1, a first collimator 130-1, a first polarizer 140-1, a beam splitter 150, an objective lens 160, a first analyzer 170-1, a first imaging lens unit 180-1, and a first detector 190-1. In addition, the tilt optical system Top' may include a second light source 110-2, a second monochromator 120-2, a second collimator 130-2, a second polarizer 140-2, a second analyzer 170-2, a second imaging lens unit 180-2, and a second detector 190-2.

[0095] Both the first light source 110-1 and the second light source 110-2 can be broadband light sources. However, according to an example embodiment, the first light source 110-1 can emit light within a different wavelength range than the second light source 110-2. The first monochromator 120-1 and the second monochromator 120-2 can perform substantially the same operation. However, when the first light source 110-1 emits light within a different wavelength range than the second light source 110-2, the wavelength of the monochromatic light output by the first monochromator 120-1 can be different from the wavelength of the monochromatic light output by the second monochromator 120-2.

[0096] Figures 8A to 8C These are flowcharts illustrating the IE-based inspection method according to example embodiments. (Refer to...) Figures 8A to 8C and Figure 1 Describe them together, and provide brief descriptions or omit references. Figures 1 to 7 The given description is repetitive.

[0097] Reference Figure 8A According to the IE-based inspection method of the example embodiment, firstly, one of the high-resolution mode and the large-area mode of the inspection device 100 is selected (S110), wherein the high-resolution mode corresponds to the vertical optical system Vop, and the first detector 190-1 of the vertical optical system Vop can have a pixel size of 500nm or smaller and 400×400μm. 2 Or a larger FOV. Additionally, the large-area mode corresponds to the tilted optical system Top, and the second detector 190-2 of the tilted optical system Top can have a pixel size of 10μm or smaller and a 9×9mm... 2 Or a smaller FOV.

[0098] After selecting a mode, the inspection target 200 is measured in the selected mode using the inspection device 100 (S130). The measurement of the inspection target 200 can be achieved by obtaining a 2D image at each wavelength using the inspection device 100. Measuring the inspection target 200 can include simultaneously measuring the pattern included in multiple cells set in a region of the inspection target 200, which corresponds to the FOV of the selected mode.

[0099] Additionally, the inspection target 200 may be provided with at least two types of measurement keys, and measuring the inspection target 200 may also include simultaneously measuring the at least two types of measurement keys. The at least two types of measurement keys may include overlay keys, focusing keys, and / or dosage keys. The at least two types of measurement keys may be arranged adjacent to each other in a 2×2 or 3×3 array structure, both types of measurement keys have a size less than or equal to 15 μm, and the at least two types of measurement keys are measured in high-resolution mode or using a vertical optical system.

[0100] After measuring the inspection target 200, it is determined whether the inspection target 200 is normal (S150). For example, the determination of whether the inspection target 200 is normal can be performed by obtaining a graph depicting the intensity of each wavelength of the measured key from a 2D image at each wavelength and comparing the obtained graph with a reference graph. The reference graph may be a graph depicting the intensity of each wavelength of the measured key, the intensity of each wavelength being obtained from a normal inspection target 200.

[0101] The IE-based inspection method of the example embodiment may perform measurements only on the inspection target 200. For example, the CD or shape of the pattern of the inspection target 200 may be measured, and the determination of whether it is normal may be omitted. In other words, in the IE-based inspection method of the example embodiment, the operation S150 of determining whether the inspection target is normal may be omitted. Therefore, the IE-based inspection method of the example embodiment may include the concept of a measurement method, and the inspection target 200 may correspond to a measurement object.

[0102] Reference Figure 8C The measurement of target 200 and the determination of whether target 200 is normal are described in more detail.

[0103] Determining whether the inspection target 200 is normal can include determining whether the semiconductor process (e.g., photolithography process) performed on the inspection target 200 is normal. For example, when determining whether the inspection target 200 is normal, if the inspection target 200 is determined to be abnormal, it can also be determined whether the photolithography process performed on the inspection target 200 is abnormal or incorrect.

[0104] Additionally, determining whether the inspection target 200 is normal (S150) may include storing feedback data obtained by performing collection, classification, indexing, etc., on data extracted from the inspection target 200 in a memory. The stored feedback data can be used for the generation and calibration of reference data. Furthermore, the feedback data and reference data can subsequently be used as control data in semiconductor processes (e.g., photolithography processes).

[0105] Reference Figure 8B According to the IE-based inspection method of the example embodiment, a 2D image at each wavelength relating to a pattern in a plurality of units of the inspection target 200 is obtained using the inspection apparatus 100 (S122). Obtaining the 2D image at each wavelength includes simultaneously measuring the pattern included in the plurality of units. The 2D image at each wavelength can be obtained in either a high-resolution mode or a large-area mode of the inspection apparatus 100. For example, in the IE-based inspection method of the example embodiment, the 2D image at each wavelength can be obtained in the large-area mode. Therefore, 2D images of patterns in a larger area at each wavelength can be obtained at a higher rate.

[0106] Next, intensity data for each wavelength is extracted from the 2D image at each wavelength (S124). Intensity data for each wavelength can be extracted for each cell and displayed in the form of a graph, for example, as shown below. Figure 6B As shown.

[0107] Next, the intensity data for each wavelength is compared with reference data (S126). Here, the reference data can be the intensity data for each wavelength obtained by measuring the intensity of the inspection target 200, which has been identified as normal. However, when no reference data is prepared in advance, the reference data can be derived by using multiple intensity data for each wavelength as basic data through deep learning.

[0108] Next, it is determined whether the overlay of the inspection target 200 is normal (S128). For example, when the error between the intensity data of each wavelength and the reference data falls within an acceptable range, the overlay status of the inspection target 200 can be determined to be normal, while when the error is outside the acceptable range, the overlay status of the inspection target 200 can be determined to be abnormal. The acceptable range can be set based on the performance of the final semiconductor device.

[0109] Reference Figure 8C According to the IE-based inspection method in the example embodiment, the checks can be performed sequentially. Figure 8A The operation of selecting the mode (S110) and the operation of measuring and inspecting the target (S130).

[0110] Next, a database (DB) is created using the data obtained in the measurement and inspection target operation (S130). Here, the DB can be created by performing collection, classification, indexing, etc., on the data extracted from the inspection target 200, and the resulting data can be stored in memory. Large amounts of data extracted from multiple inspection targets 200 can be stored in the DB.

[0111] After creating the database (DB), deep learning is performed using multiple data entries from the DB (S145). Depending on the characteristics of the data, various deep learning methods may be employed. For example, deep learning can utilize learning algorithms such as Convolutional Neural Networks (CNNs), Deep Neural Networks (DNNs), and Recurrent Neural Networks (RNNs). Reference data used for the extracted data can be derived through deep learning.

[0112] After performing deep learning, it is determined whether the inspection target 200 is normal (S150). When determining whether the inspection target 200 is normal, reference data obtained during the aforementioned deep learning can be used. For example, a graph describing the intensity of the measurement bond at each wavelength can be obtained from a 2D image at each wavelength, and the normality of the inspection target 200 can be determined by comparing the obtained graph with the reference graph obtained during deep learning.

[0113] The data used to create the database and the reference data obtained through deep learning can then be used as control data in semiconductor processes (e.g., photolithography).

[0114] Figure 9A and Figure 9B These are flowcharts illustrating methods for manufacturing semiconductor devices using an IE-based inspection method according to example embodiments. (Refer to...) Figure 9A and Figure 9B and Figure 1 Describe them together, or omit references in a brief description. Figures 8A to 8C The given description is repetitive.

[0115] Reference Figure 9A According to the method for manufacturing a semiconductor device in the example embodiment, the operation of first selecting a mode (S210), measuring the wafer (S230), and determining whether the wafer is normal (S250) are performed sequentially. The operation of selecting the mode S210, measuring the wafer S230, and determining whether the wafer is normal S250 are related to... Figure 8A The operations described in the IE-based inspection method are the same. However, despite... Figure 8AIn this case, the inspection target 200 is not specified, but the inspection target 200 in the method of manufacturing a semiconductor device according to the example embodiment can be specified as a wafer. In the example embodiment, the wafer is measured in a large-area mode or by means of a tilting optical system.

[0116] Next, when the wafer is determined to be normal (yes) in the operation of determining whether the wafer is normal (S250), subsequent semiconductor processes are performed on the wafer (S260). Through these subsequent semiconductor processes, multiple semiconductor devices can be manufactured from the wafer. These subsequent semiconductor processes can include various processes. For example, they can include deposition processes, etching processes, ion processes, cleaning processes, etc. Furthermore, they can include testing processes for semiconductor devices at the wafer level. Additionally, they can include processes for individualizing the wafer into semiconductor chips and processes for packaging semiconductor chips. Here, the packaging process can refer to the process of mounting semiconductor chips on a printed circuit board (PCB) and encapsulating the resulting semiconductor chips with a sealant, and can include forming a stacked package by stacking multiple semiconductors in multiple layers on the PCB or forming a package stack (POP) structure by stacking stacked packages on top of each other. Semiconductor devices or semiconductor packages can be manufactured through the semiconductor chip packaging process.

[0117] When a wafer is determined to be abnormal (no) during the operation of determining whether the wafer is normal (S250), for example, when the wafer is defective, the wafer is discarded and a cause analysis is performed, thereby changing the process conditions (S270). Here, the process conditions may be, for example, the process conditions of a photolithography process. As an example, when the defect is caused by poor focusing, the focus position is adjusted, and when the defect is caused by poor dosage, the dosage can be adjusted. Next, the method can return to the operation of the selection mode (S210). However, the wafer to be inspected in subsequent operations may be a wafer that has already undergone photolithography when the process conditions were changed during the operation of changing the process conditions (S270).

[0118] Reference Figure 9B According to the method for manufacturing a semiconductor device in the example embodiment, firstly, measurement keys are designed (S201). For example, at least two types of measurement keys are designed. For example, measurement keys may include focus keys, overlay keys, or dosage keys. In addition, the measurement keys may be designed to have a size greater than or equal to 30 μm or a size of 15 μm or smaller.

[0119] When the measurement keys are designed to have a size of 15 μm or smaller, they can be designed as a 2×2 or 3×3 array structure, such as... Figure 5B , Figure 5C and Figure 5DAs shown. Additionally, in a 2×2 or 3×3 array structure, all measurement keys can be the same, or at least one measurement key can be different.

[0120] After the measurement keys are designed, they are formed on the wafer (S205). For example, a mask for the designed measurement keys can be formed, and then the measurement keys can be transferred onto the wafer by photolithography, thereby forming the measurement keys on the wafer.

[0121] After forming the measurement key on the wafer, the following operations are executed sequentially: selecting the mode (S210), measuring the wafer (S230), and determining whether the wafer is functioning correctly (S250). The operations of selecting the mode (S210), measuring the wafer (S230), and determining whether the wafer is functioning correctly (S250) are related to... Figure 8A The operations described in the IE-based inspection method are the same. However, in the operation of the above-described design of the measurement key, when the measurement key is formed in a 2×2 or 3×3 array structure and has a size of 15μm or smaller, a high-resolution mode can be selected in the mode selection operation (S210).

[0122] Next, as Figure 9A Depending on whether the wafer is functioning correctly, the process can proceed with subsequent semiconductor processing operations (S260) or change the process conditions (S270). After changing the process conditions (S270), the method can proceed to the operation of forming measurement bonds on the wafer (S205). The photolithography process with the changed process conditions can be applied to the operation of forming measurement bonds on the wafer (S205). Alternatively, forming measurement bonds on the wafer can include forming another pattern on the wafer, other than the measurement bonds, using the changed photolithography process.

[0123] While exemplary embodiments have been specifically shown and described, it should be understood that various changes in form and detail may be made without departing from the spirit and scope of the appended claims.

Claims

1. An inspection method based on ellipsometric imaging, comprising: Choose one mode from a first mode with a first field of view and a second mode with a second field of view of the ellipsoidal imaging-based examination device; as well as The inspection target is measured using the ellipsoidal imaging-based inspection device in the selected mode. The measurement and inspection target includes simultaneously measuring patterns contained in multiple units set in the area of ​​the inspection target, the area corresponding to the field of view of the selected pattern. The target of the inspection is a semiconductor chip. The first mode is a high-resolution mode achieved by a vertical optical system. The second mode is a large-area mode implemented by a tilted optical system, which includes a second detector tilted relative to the platform on which the semiconductor chip is disposed. The second detector is configured to obtain a two-dimensional image of the entire area of ​​the semiconductor chip by performing a single imaging operation in the second mode.

2. The inspection method based on ellipsoidal imaging according to claim 1, wherein, The inspection target is a wafer comprising multiple of the said semiconductor chips, and The overlay at each location of the wafer is determined by averaging the overlay values ​​measured over the entire area of ​​the wafer.

3. The inspection method based on ellipsoidal imaging according to claim 1, wherein... The overlay at each location of the semiconductor chip is determined by averaging the overlay values ​​measured over the entire area of ​​the semiconductor chip.

4. The inspection method based on ellipsoidal imaging according to claim 1, wherein, The measurement and inspection objectives include: obtaining a two-dimensional image of the pattern included in the plurality of units at each wavelength; and extracting measurement data for each wavelength based on the two-dimensional image corresponding to each wavelength.

5. The inspection method based on ellipsometric imaging according to claim 4, further comprising: Based on the measurement results, determine whether the inspection target is normal. The determination of whether the inspection target is normal includes: determining the overlay of the inspection target by comparing the measured data of each wavelength with reference data.

6. The inspection method based on ellipsometric imaging according to claim 5, wherein, The reference data is obtained from inspection targets that have been identified as being in a normal state, or it is obtained based on deep learning by using data from multiple measurements at various wavelengths as the base data.

7. The inspection method based on ellipsometric imaging according to claim 1, wherein, The vertical optical system includes a first detector with a pixel size of less than or equal to 500 nm, and a first field of view greater than or equal to 400 × 400 µm. 2 ,as well as The second mode is a large-area mode implemented by the second detector having a pixel size of less than or equal to 10 μm, and the second field of view is less than or equal to 9 × 9 mm. 2 .

8. The inspection method based on ellipsoidal imaging according to claim 1, wherein, The inspection target is equipped with at least two types of measurement keys, and The measurement and inspection target also includes simultaneously measuring the at least two types of measurement keys.

9. The inspection method based on ellipsometric imaging according to claim 8, wherein, The at least two types of measurement keys include overlay keys, focus keys, and / or dose keys.

10. The inspection method based on ellipsometric imaging according to claim 9, wherein, The at least two types of measurement keys are arranged adjacent to each other in a 2×2 or 3×3 array structure, the at least two types of measurement keys have a size of less than or equal to 15µm, and the at least two types of measurement keys are measured in the high-resolution mode corresponding to the first mode.

11. An inspection method based on ellipsometric imaging, comprising: In one of the first or second modes, a two-dimensional image of the pattern included in multiple units of the inspected target at each wavelength is obtained by an elliptic imaging-based inspection device. as well as Extract the intensity data of each wavelength from the two-dimensional image; The acquisition of a two-dimensional image at each wavelength includes simultaneously measuring the patterns included in the plurality of units. The inspection target is a semiconductor chip or a wafer comprising multiple semiconductor chips. The first mode is a high-resolution mode achieved by a vertical optical system. The second mode is a large-area mode implemented by a tilted optical system, which includes a second detector tilted relative to the platform on which the semiconductor chip is disposed. The second detector is configured to obtain a two-dimensional image of the entire area of ​​the semiconductor chip by performing a single imaging operation in the second mode.

12. The inspection method based on ellipsoidal imaging according to claim 11, in, The overlay at each location of the wafer is determined by averaging the overlay values ​​measured over the entire area of ​​the wafer.

13. The inspection method based on ellipsometric imaging according to claim 11, further comprising: The intensity data for each wavelength is compared with reference data; as well as Based on the comparison results, determine whether the overlay of the inspection target is normal; The reference data is obtained from inspection targets that have been identified as being in a normal state, or it is obtained through deep learning based on multiple intensity data of various wavelengths as the base data.

14. A method for manufacturing a semiconductor device, comprising: Choose one mode from a first mode with a first field of view and a second mode with a second field of view of the ellipsoidal imaging-based examination device; The wafer is measured using the ellipsometry-based inspection device in the selected mode; Based on the measurement results, determine whether the wafer is functioning properly, and Based on the confirmation that the wafer is functioning correctly, semiconductor processes are performed on the wafer. The measurement wafer includes the ability to simultaneously measure patterns contained in multiple cells arranged in a region of the wafer, the region corresponding to the field of view of a selected pattern. The first mode is a high-resolution mode achieved by a vertical optical system. The second mode is a large-area mode implemented by a tilted optical system, which includes a second detector tilted relative to the platform on which the wafer is disposed. The second detector is configured to obtain a two-dimensional image of the entire area of ​​the semiconductor chip included in the wafer by performing a single imaging operation in the second mode.

15. The method of manufacturing a semiconductor device according to claim 14, wherein, The overlay at each location of the wafer is determined by averaging the overlay values ​​measured over the entire area of ​​the wafer.

16. The method of manufacturing a semiconductor device according to claim 14, wherein, The measurement chip includes: Obtain the two-dimensional image of the pattern included in the plurality of units at each wavelength; and Intensity data for each wavelength is extracted from the two-dimensional image for each wavelength.

17. The method of manufacturing a semiconductor device according to claim 16, wherein, Determining whether the wafer is functioning correctly involves comparing the intensity data for each wavelength with reference data.

18. The method of manufacturing a semiconductor device according to claim 17, wherein, The reference data is obtained from a chip that has been determined to be in a normal state, or it is obtained based on deep learning by using multiple intensity data of various wavelengths as the base data.

19. The method of manufacturing a semiconductor device according to claim 14, the method further comprising: Before selecting one of the first and second modes, at least two types of measurement keys are designed; as well as The at least two types of measurement keys are provided on the wafer. The measuring chip also includes a measuring chip that simultaneously measures the at least two types of measuring keys.

20. The method of manufacturing a semiconductor device according to claim 19, wherein, The design of at least two types of measurement keys includes: designing each of the at least two types of measurement keys to have a size greater than or equal to 30 μm or less than or equal to 15 μm.

21. The method of manufacturing a semiconductor device according to claim 20, wherein, Each of the at least two types of measurement keys is designed to have a size of 15 μm or smaller, and the at least two types of measurement keys are arranged adjacent to each other in a 2×2 or 3×3 array structure. The at least two types of measurement keys are measured in the high-resolution mode corresponding to the first mode.

Images