Measurement methods, measuring apparatus and markings

Abstract

This disclosure relates to a measurement method, a measurement apparatus, and a marker. The measurement method includes generating marker position information, determining at least one of a first alignment pattern and a second alignment pattern, and calculating the offset between the first layer and the second layer. The marker position information is generated after the second layer is formed on the first layer, indicating the relative positional relationship between the first alignment marker and the second alignment marker. The first alignment marker is formed on the first layer and includes bright and dark areas, and the second alignment marker is formed on the second layer and includes bright and dark areas. The first alignment pattern represents the arrangement pattern of the bright and dark areas of the first alignment marker. The second alignment pattern represents the arrangement pattern of the bright and dark areas of the second alignment marker. The first alignment pattern is determined based on imaging data of a reference marker formed in a region different from the region where the first alignment marker and the region where the second alignment marker are formed. The offset is calculated based on at least one of the first and second alignment patterns and the marker position information.

Description

[0001] This application is based on and pursues the priority interest of Japanese Patent Application No. 2021-151220, filed on September 16, 2021, the contents of which are incorporated herein by reference in their entirety. Technical Field

[0002] The embodiments of the present invention relate to a measurement method, a measurement device, and a marking. Background Technology

[0003] In semiconductor device manufacturing processes, techniques are employed to measure the offset between multiple layers constituting a semiconductor device using alignment marks, and the offset between the processed component and the template in nanoimprinting. For example, a technique exists where marks with bright and dark areas are formed in a line-and-space pattern on the lower and upper layers, respectively. The offset between the lower and upper layers is measured by observing the moiré fringes generated due to the overlap of the lower and upper marks. Summary of the Invention

[0004] Embodiments of the present invention provide a method, apparatus, and marking for measuring the offset between multiple layers in the manufacturing process of a semiconductor device with high precision.

[0005] According to one embodiment of the present invention, a measurement method is provided. The measurement method includes generating marker position information, determining at least one of a first alignment pattern and a second alignment pattern, and calculating the offset between a first layer and a second layer. The marker position information is generated after the second layer is formed on the first layer, and indicates the relative positional relationship between the first alignment marker and the second alignment marker. The first alignment marker is formed on the first layer and includes bright and dark areas, and the second alignment marker is formed on the second layer and also includes bright and dark areas. The first alignment pattern represents the arrangement pattern of the bright and dark areas of the first alignment marker. The second alignment pattern represents the arrangement pattern of the bright and dark areas of the second alignment marker. The first alignment pattern is determined based on imaging data of reference markers formed in regions different from the regions where the first alignment marker and the second alignment marker are formed. The offset is calculated based on at least one of the first and second alignment patterns and the marker position information.

[0006] Based on the above configuration, a method, a measuring apparatus, and a marking can be provided for measuring the offset between multiple layers in the manufacturing process of a semiconductor device with high precision. Attached Figure Description

[0007] Figure 1 This is a cross-sectional view schematically illustrating an example of the configuration of the semiconductor device according to the first embodiment.

[0008] Figure 2 This is a top view showing an example of the configuration of the first and second layers according to the first embodiment.

[0009] Figure 3 This is a top view showing an example of the configuration of the first mark involved in the first embodiment.

[0010] Figure 4 This is a top view showing an example of the configuration of the second mark involved in the first embodiment.

[0011] Figure 5 This is a diagram illustrating an example of moiré stripes when the first and second moiré marks involved in the first embodiment are in their normal positions.

[0012] Figure 6 This is a diagram illustrating an example of moiré fringes when the first and second moiré marks involved in the first embodiment are not in their normal positions.

[0013] Figure 7 This is a diagram showing a comparison between the first moiré mark, which is a normal pattern, and the first moiré mark, which is a reverse pattern, according to the first embodiment.

[0014] Figure 8 This is a diagram illustrating an example of moiré stripes in the case where the first and second moiré marks, which are reverse patterns according to the first embodiment, are not in their normal positions.

[0015] Figure 9 This is a flowchart illustrating an example of the processing in the measurement method according to the first embodiment.

[0016] Figure 10 This is a flowchart illustrating an example of the moiré fringe measurement process according to the first embodiment.

[0017] Figure 11 This is a block diagram illustrating an example of the configuration of the measuring device according to the first embodiment.

[0018] Figure 12 This is a flowchart illustrating an example of the processing in the measurement method according to the second embodiment.

[0019] Figure 13 This is a flowchart illustrating an example of the moiré fringe measurement process according to the second embodiment.

[0020] Figure 14 This is a diagram schematically illustrating an example of the manufacturing process of the semiconductor device according to the third embodiment.

[0021] Figure 15 This is a top view showing an example of the configuration of the first mark involved in the third embodiment.

[0022] Figure 16 This is a top view showing an example of the configuration of the second mark involved in the third embodiment.

[0023] Figure 17 This is a diagram illustrating an example of the configuration of the first and second marks used in the measurement method according to the fourth embodiment. Detailed Implementation

[0024] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, the present invention is not limited to these embodiments. Furthermore, the constituent elements in the embodiments include those readily conceived by those skilled in the art or substantially the same constituent elements.

[0025] (First Embodiment)

[0026] In this embodiment, a technique for measuring the offset between multiple layers constituting a semiconductor device during the manufacturing process of a semiconductor device will be described.

[0027] Figure 1 This is a cross-sectional view schematically illustrating an example of the configuration of the semiconductor device 1 according to the first embodiment. In the figure, the X-axis corresponds to the left-right direction of the paper, the Y-axis corresponds to the direction orthogonal to the paper, and the Z-axis corresponds to the direction orthogonal to the X-axis and Y-axis (stack direction).

[0028] Figure 1 The semiconductor device 1 illustrated includes a substrate 11, a first layer 12, and a second layer 13. The first layer 12 is formed on the substrate 11, and the second layer 13 is formed on the first layer 12. The specific configuration of the substrate 11, the first layer 12, and the second layer 13 should be appropriately determined according to the type of semiconductor device 1. For example, the substrate 11 may be a silicon substrate, the first layer 12 may be a silicon oxide film with a wiring layer having a predetermined circuit pattern, and the second layer 13 may be a photoresist. In this case, the semiconductor device 1 is formed by finally peeling off the second layer 13. Alternatively, one or more layers may be formed on the second layer 13. In this embodiment, the case of measuring the offset between the first layer 12 and the second layer 13 will be described.

[0029] Figure 2 This is a top view illustrating an example of the configuration of the first layer 12 and the second layer 13 according to the first embodiment. For example... Figure 2As shown, multiple exposure (shot) areas 20 are provided on the upper surfaces of the first layer 12 and the second layer 13. Each exposure area 20 includes a device area 21 and a dicing area 22. The device area 21 is the area for forming predetermined circuit patterns, resist patterns, etc. The dicing area 22 is a frame-shaped area provided at the periphery of the device area 21. When the processing of the device area 21 is completed, dicing is performed in the dicing area 22 to form multiple chips, each having a circuit pattern, etc. Marks (first mark and second mark described later) for measuring the offset between the first layer 12 and the second layer 13 are formed in the dicing area 22.

[0030] Figure 3 This is a top view showing an example of the configuration of the first reference numeral M1 according to the first embodiment. Figure 4 This is a top view showing an example of the configuration of the second mark M2 according to the first embodiment. The first mark M1 is formed in the dicing groove region 22 of the first layer 12. The second mark M2 is formed in the dicing groove region 22 of the second layer 13.

[0031] like Figure 3 As shown, the first mark M1 includes a first moiré mark Mm1 (an example of a first alignment mark) and a first reference mark Ms1. The first moiré mark Mm1 is used to connect with the second moiré mark Mm2 (described later) Figure 4 The overlapping of the two parts creates the markings for producing moiré fringes, which include multiple bright areas B1 and multiple dark areas D1. The bright areas B1 are the parts with higher light reflection intensity than the dark areas D1. The specific formation of the bright areas B1 and the dark areas D1 should be appropriately selected according to the configuration of the semiconductor device 1, but for example, the bright areas B1 can be formed with areas containing metal such as tungsten, and the dark areas D1 can be formed with areas without metal (such as exposed silicon oxide film).

[0032] In this embodiment, each bright portion B1 and each dark portion D1 has a linear shape extending along the Y-axis (an example of the first direction). Multiple bright portions B1 and multiple dark portions D1 are alternately arranged along the X-axis (an example of the second direction) within a first region Ra1 having a predetermined area. Furthermore, the first region Ra1 is set to be within... Figure 3 The area enclosed by the dotted line.

[0033] The first reference mark Ms1 is a mark used to determine the arrangement pattern of the bright part B1 and the dark part D1 in the first moiré mark Mm1. The arrangement pattern referred to here indicates the positional relationship between the bright part B1 and the dark part D1 within the first region Ra1. As an arrangement pattern, it can be a normal pattern determined in advance by design data, etc., or a reversed pattern in which the positional relationship between the bright part B1 and the dark part D1 is reversed relative to the normal pattern. Figure 3The first moiré mark Mm1 shown is set as the mark of the normal pattern (the reverse pattern will be described later).

[0034] The first reference mark Ms1 has optical properties corresponding to either the bright portion B1 or the dark portion D1 of the first moiré mark Mm1. These optical properties can be, for example, reflectivity for inspection light having a predetermined wavelength (e.g., wavelengths in the visible to near-infrared region). The first reference mark Ms1 in this embodiment has optical properties corresponding to the bright portion B1 (e.g., reflectivity with an error of less than a threshold compared to the reflectivity of the bright portion B1), and can be made of the same material as the bright portion B1. A first blank region Rbk1 with optical properties different from the first reference mark Ms1 is provided around the first reference mark Ms1 (in this embodiment, the region adjacent along the X-axis). The first blank region Rbk1 in this embodiment has optical properties corresponding to the dark portion D1. Furthermore, the first blank region Rbk1 can be, for example,... Figure 3 Multiple are provided as shown (two in this embodiment), or only one may be provided in any region adjacent to the first reference mark Ms1.

[0035] exist Figure 3 In this diagram, P1 represents the pitch between the bright portion B1 and the dark portion D1 in the first moiré mark Mm1, Wb1 represents the width of the bright portion B1 along the X-axis, Wd1 represents the width of the dark portion D1 along the X-axis, and CL1 represents the center position of the first region Ra1 along the X-axis. Additionally, C1 represents the distance between the first moiré mark Mm1 (the first region Ra1) and the first reference mark Ms1, Ws1 represents the width of the first reference mark Ms1 along the X-axis, and Wbk1 represents the width of the first blank region Rbk1 along the X-axis.

[0036] The spacing P1 of the first moiré mark Mm1 and the spacing P2 of the second moiré mark Mm2 (described later) Figure 4In this embodiment, the relationship P1 < P2 holds. The interval distance C1 is preferably 20 μm or less. This makes it easy to make the first moiré mark Mm1 and the first reference mark Ms1 fall within the same imaging area, thereby improving the efficiency of image processing. The width Ws1 of the first reference mark Ms1 is larger than the width Wb1 of the bright part B1 and the width Wd1 of the dark part D1, preferably 1.5 μm or more. This allows for accurate measurement of the optical characteristics of the first reference mark Ms1 (e.g., the intensity of reflected light generated by irradiating the first reference mark Ms1 with the inspection light) when using visible light or near-infrared light as the inspection light. Furthermore, according to the same viewpoint, the width Wbk1 of the first blank area Rbk1 is larger than the width Wb1 of the bright part B1 and the width Wd1 of the dark part D1, preferably 1.5 μm or more.

[0037] With the configuration described above, the optical characteristics of the first reference mark Ms1 are measured based on the imaging data of the first reference mark Ms1. The region within the first region Ra1 that has optical characteristics equivalent to the first reference mark Ms1 can be identified as the bright portion B1 of the first moiré mark Mm1. That is, the arrangement pattern of the bright portion B1 and the dark portion D1 in the first moiré mark Mm1 can be determined based on the imaging data of the first reference mark Ms1.

[0038] like Figure 4 As shown, the second mark M2 includes a second moiré mark Mm2 (an example of a second alignment mark) and a second reference mark Ms2. The second moiré mark Mm2 is used to align with the first moiré mark Mm1 ( Figure 3 The overlapping of the two layers creates the markings that produce moiré fringes, including multiple bright areas B2 and multiple dark areas D2. The bright areas B2 are the portions with higher light reflection intensity than the dark areas D2. The specific formation of the bright areas B2 and the dark areas D2 should be appropriately selected according to the configuration of the semiconductor device 1. For example, the bright areas B2 can be formed by slits (openings) formed in the material constituting the second layer 13 (e.g., resist), and the dark areas D1 can be formed by areas where no slits are formed (e.g., where resist remains).

[0039] In this embodiment, each bright portion B2 and each dark portion D2, like the bright portion B1 and dark portion D1 of the first reference mark Ms1, has a linear shape extending along the Y-axis. Multiple bright portions B2 and multiple dark portions D2 are alternately arranged along the X-axis within a second region Ra2 having a predetermined area. Furthermore, the second region Ra2 is set to be within... Figure 4 The area enclosed by the dotted line.

[0040] The second reference mark Ms2 is a mark used to determine the arrangement pattern of the bright part B2 and the dark part D2 in the second moiré mark Mm2. The arrangement pattern referred to here indicates the positional relationship between the bright part B2 and the dark part D2 within the second region Ra2, including a predetermined normal pattern and a reversed pattern in which the positional relationship between the bright part B2 and the dark part D2 is inverted relative to the normal pattern. Let it be... Figure 4 The second moiré mark Mm2 shown corresponds to the usual pattern.

[0041] The second reference mark Ms2 has optical properties corresponding to either the bright portion B2 or the dark portion D2 of the second moiré mark Mm2. In this embodiment, the second reference mark Ms2 has optical properties corresponding to the bright portion B2. A second blank region Rbk2 with optical properties different from the second reference mark Ms2 is provided around the second reference mark Ms2. In this embodiment, the second blank region Rbk2 has optical properties corresponding to the dark portion D2.

[0042] exist Figure 4 In this diagram, P2 represents the spacing between the bright portion B2 and the dark portion D2 in the second moiré mark Mm2; Wb2 represents the width of the bright portion B2 along the X-axis; Wd2 represents the width of the dark portion D2 along the X-axis; and CL2 represents the center position of the second region Ra2 along the X-axis. Additionally, C2 represents the distance between the second moiré mark Mm2 (the second region Ra2) and the second reference mark Ms2; Ws2 represents the width of the second reference mark Ms2 along the X-axis; and Wbk2 represents the width of the second blank region Rbk2 along the X-axis.

[0043] The spacing P2 of the second moiré mark Mm2 is the same as the spacing P1 of the first moiré mark Mm1. Figure 3 Unlike other methods, in this embodiment, the relationship P1 < P2 holds. The spacing distance C2 is preferably 20 μm or less, similar to the spacing distance C1 in the first mark M1. The width Ws2 of the second reference mark Ms2 and the width Wbk2 of the second blank area Rbk2 are larger than the width Wb2 of the bright area B2 and the width Wd2 of the dark area D2, preferably 1.5 μm or more.

[0044] Based on the above configuration, the optical characteristics of the second reference mark Ms2 can be determined using the imaging data of the second reference mark Ms2, and the region within the second region Ra2 that has the same optical characteristics as the second reference mark Ms2 is identified as the bright part B2 of the second moiré mark Mm2. That is, the arrangement pattern of the bright part B2 and the dark part D2 in the second moiré mark Mm2 can be determined based on the imaging data of the second reference mark Ms2.

[0045] Figure 5This diagram illustrates an example of moiré fringes when the first moiré mark Mm1 and the second moiré mark Mm2, according to the first embodiment, are in their normal positions. After the second layer 13 is formed on the first layer 12, when the area where the first moiré mark Mm1 and the second moiré mark Mm2 overlap is viewed from above, moiré fringes corresponding to the positional relationship between the bright areas B1, B2 and the dark areas D1, D2 can be observed, wherein the first moiré mark Mm1 is formed on the first layer 12 and the second moiré mark Mm2 is formed on the second layer 13. Figure 5 The illustration shows the state where the first moiré marker Mm1 and the second moiré marker Mm2 are in a predetermined normal position. The normal position here is when the center line CL1 of the first moiré marker Mm1 coincides with the center line CL2 of the second moiré marker Mm2, or their offset is within a threshold value. However, the normal position is not limited to this.

[0046] exist Figure 5 In this context, "light" and "dark" refer to the bright and dark areas of the moiré fringes. For example... Figure 5 As shown, the densely packed bright portions B1 and B2 of the two moiré marks Mm1 and Mm2 form the bright portions of the moiré fringes, and the densely packed dark portions D1 and D2 of the two moiré marks Mm1 and Mm2 form the dark portions of the moiré fringes. Based on the positions of the bright and dark portions of these moiré fringes, the offset between layer 12 and layer 23 can be determined.

[0047] Figure 6 This is a diagram illustrating an example of moiré fringes when the first moiré mark Mm1 and the second moiré mark Mm2, according to the first embodiment, are not in their normal positions. Figure 6 The diagram illustrates a situation where the center line CL2 of the second moiré marker Mm2 is offset to the right by a distance ΔD relative to its normal position (the position of the center line CL1). When such an offset occurs in the relative positional relationship between the two moiré markers Mm1 and Mm2, as shown in the diagram... Figure 5 and Figure 6 By comparing the positions of the "bright" and "dark" areas, we can see the changes in the positions of the bright and dark parts of the moiré fringes. Based on these changes in the moiré fringes, we can determine the offset between layer 12 and layer 23.

[0048] Furthermore, the example shown above illustrates that the darker areas of the moiré fringes are centered when the first moiré marker Mm1 and the second moiré marker Mm2 are in their normal positions. Figure 5However, the arrangement of the moiré fringes is not limited to this. For example, when the first moiré mark Mm1 and the second moiré mark Mm2 are in their normal positions, the bright part of the moiré fringe can also be located in the center. Furthermore, while the examples shown above illustrate the formation of the first moiré mark Mm1 and the second moiré mark Mm2 as lines and intervals with a certain spacing, this spacing is not limited to a fixed interval as long as the pattern is repeated. Additionally, the pattern of the first moiré mark Mm1 and the second moiré mark Mm2 is not limited to lines and intervals; for example, it can also be a checkerboard pattern, etc.

[0049] Here, the reversal of the arrangement patterns of the bright areas B1, B2 and the dark areas D1, D2 will be explained. The arrangement patterns of the bright areas B1 and D1 in the first moiré mark Mm1, or the arrangement patterns of the bright areas B2 and D2 in the second moiré mark Mm2, may be reversed during the processing of each layer 12, 13 (e.g., when forming patterns by photolithography).

[0050] Figure 7 This is a diagram comparing the first moiré mark Mm1 as a normal pattern and the first moiré mark Mm1' as a reverse pattern according to the first embodiment. Figure 7 As shown, the positional relationship between the bright part B1 and the dark part D1 in the first region Ra1 of the first moiré mark Mm1' corresponding to the inverted pattern is reversed relative to the positional relationship between the bright part B1 and the dark part D1 in the first region Ra1 of the first moiré mark Mm1 corresponding to the normal pattern. The first moiré mark of this embodiment has a normal pattern (Mm1) or an inverted pattern (Mm1').

[0051] Figure 8 This diagram illustrates an example of moiré fringes when the first moiré mark Mm1' and the second moiré mark Mm2, which are reverse patterns according to the first embodiment, are not in their normal positions. Here, the case where the first moiré mark Mm1' has a reverse pattern will be described. Figure 8 Examples are shown in the context of... Figure 6 The situation shown is similar: the second moiré mark Mm2 is shifted a distance ΔD to the right of the figure from its normal position, and the arrangement pattern of the bright part B1 and the dark part D1 of the first moiré mark Mm1' is relative to... Figure 6 The moiré fringes produced when the arrangement pattern (normal pattern) of the first moiré mark Mm1 shown is reversed. As according to Figure 6 and Figure 8 As can be seen from the comparison, even if the offset (distance ΔD) is the same, the positions of the bright and dark parts of the moiré fringes will change when the arrangement patterns of the bright part B1 and the dark part D1 are reversed. This phenomenon may also occur in the case where the arrangement patterns of the bright part B2 and the dark part D2 in the second moiré mark Mm2 are reversed.

[0052] The measurement method involved in this embodiment includes a process for removing the effects caused by the inversion of the bright parts B1, B2 and the dark parts D1, D2 of the first moiré mark Mm1 or the second moiré mark Mm2 as described above.

[0053] Figure 9 This is a flowchart illustrating an example of a process in the measurement method according to the first embodiment. The measurement method according to this embodiment is for measuring the offset between a first layer 12 and a second layer 13 constituting a part of a semiconductor device 1, including a marker position detection step (S101) for detecting the positions of a first marker M1 and a second marker M2. The marker position detection step can be performed, for example, after the formation of the second layer 13 or during the formation of the second layer 13, based on imaging data obtained by taking pictures of the second layer 13 from above. When the marker position detection step is performed after the formation of the second layer 13, an opening is formed in the portion of the second layer 13 corresponding to the position of the first marker M1, so that the first marker M1 formed in the first layer 12 can be photographed.

[0054] Then, a brightness determination step (S102) is performed to determine the brightness of the arrangement pattern for at least one of the first moiré mark Mm1 and the second moiré mark Mm2. At this time, the arrangement pattern of the first moiré mark Mm1 (whether it is a normal pattern or a reversed pattern) is determined based on the imaging data of the first reference mark Ms1, and the arrangement pattern of the second moiré mark Mm2 is determined based on the imaging data of the second reference mark Ms2. For example, the arrangement pattern of the first moiré mark Mm1 can be determined by determining, based on the optical characteristics (intensity of reflected light, etc.) of the first reference mark Ms1, which part of the first region Ra1 belongs to the bright part B1. Similarly, the arrangement pattern of the second moiré mark Mm2 can also be determined, for example, by determining, based on the optical characteristics of the second reference mark Ms2, which part of the second region Ra2 belongs to the bright part B2.

[0055] Then, a moiré fringe measurement step (S103) is performed to measure the moiré fringes caused by the overlap of the first moiré mark Mm1 and the second moiré mark Mm2 (an example of a mark measurement step). The moiré fringe measurement step can be performed, for example, based on imaging data obtained by taking a picture of the second layer 13 from above after the second layer 13 has been formed. At this time, based on the determination result (arrangement pattern information) of the brightness determination step, the moiré fringe measurement result is corrected so that the influence caused by the reversal of the arrangement pattern of the first moiré mark Mm1 and / or the second moiré mark Mm2 is removed.

[0056] Then, an offset calculation step (S104) is performed to calculate the offset (distance ΔD) between the first layer 12 (first moiré mark Mm1) and the second layer 13 (second moiré mark Mm2) based on the measurement results (moiré fringe information) from the moiré fringe measurement step. The moiré fringe information is an example of mark position information representing the relative positional relationship between the first moiré mark Mm1 and the second moiré mark Mm2. At this time, as described above, the moiré fringe information is corrected based on the arrangement pattern of the first moiré mark Mm1 and / or the second moiré mark Mm2 in the moiré fringe measurement step. Therefore, the offset calculated here is an offset that removes the effect of the reversal of the arrangement pattern.

[0057] Figure 10 This is a flowchart illustrating an example of the moiré fringe measurement process according to the first embodiment. When the above-described moiré fringe measurement step (S103) begins, the arrangement pattern information generated by the brightness / darkness determination step (S102) is obtained (S201), and moiré fringe information related to the moiré fringes generated due to the overlap of the first moiré mark Mm1 and the second moiré mark Mm2 is generated (S202). The arrangement pattern information here includes information representing the arrangement pattern of the first moiré mark Mm1 (first arrangement pattern) and information representing the arrangement pattern of the second moiré mark Mm2 (second arrangement pattern). The moiré fringe information includes information representing the positions of the bright and dark parts of the moiré fringes generated due to the overlap of the first moiré mark Mm1 and the second moiré mark Mm2 (e.g., the offset of the moiré fringe relative to a predetermined position).

[0058] Then, it is determined whether the first arrangement pattern is a reversed pattern (S203). If the first arrangement pattern is a reversed pattern (S203: Yes), it is further determined whether the second arrangement pattern is a reversed pattern (S204). If the second arrangement pattern is a reversed pattern (S204: Yes), the moiré fringe information is corrected to remove the influence of both the first and second arrangement patterns being reversed patterns (S205). In step S204, if the second arrangement pattern is not a reversed pattern (S204: No), the moiré fringe information is corrected to remove the influence of only the first arrangement pattern being a reversed pattern (S206).

[0059] If the first pattern arrangement is not a reversed pattern in step S203 (S203: No), it is determined whether the second pattern arrangement is a reversed pattern (S207). If the second pattern arrangement is a reversed pattern in step S207 (S207: Yes), the moiré fringe information is corrected to remove the influence of only the second pattern arrangement being a reversed pattern (S208). If the second pattern arrangement is not a reversed pattern in step S207 (S207: No), since both the first and second patterns are normal patterns, the moiré fringe information is not corrected (S209).

[0060] According to the measurement method described above, even if at least one of the first moiré mark Mm1 and the second moiré mark Mm2 is reversed, the offset between the first layer 12 and the second layer 13 can be accurately measured.

[0061] Figure 11 This is a block diagram illustrating an example of the configuration of the measuring apparatus 101 according to the first embodiment. The measuring apparatus 101 according to this embodiment is an apparatus that measures the offset between multiple layers constituting a semiconductor device by performing a measurement method as described above, and generates offset information representing the measurement result.

[0062] The measuring device 101 includes an imaging device 111 and an information processing device 112. The imaging device 111 can be configured, for example, using a digital camera to capture images of the semiconductor device 1, including the first layer 12 and the second layer 13 which are the objects of measurement, from above, or an illumination mechanism that illuminates the first reference mark Ms1 and the second reference mark Ms2 with inspection light of a predetermined wavelength. The information processing device 112 is, for example, a computer configured with a CPU (Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory), auxiliary storage, a user interface, and a communication interface, and executes various computational processes to implement the aforementioned measuring method according to the program stored in the ROM and auxiliary storage.

[0063] The information processing device 112 includes a moiré fringe measurement unit 121 (an example of a marker measurement unit), a brightness determination unit 122, and a calculation unit 123. The moiré fringe measurement unit 121 generates moiré fringe information based on imaging data of the overlapping area of ​​a first moiré marker Mm1 and a second moiré marker Mm2 obtained by the imaging device 111. The brightness determination unit 122 determines the arrangement pattern of the first moiré marker Mm1 based on imaging data of a first reference marker Ms1 obtained by the imaging device 111, and determines the arrangement pattern of the second moiré marker Mm2 based on imaging data of a second reference marker Ms2 obtained by the imaging device 111. The calculation unit 123 calculates the offset between the first layer 12 and the second layer 13 based on the measurement results (moiré fringe information) of the moiré fringe measurement unit 121 and the determination results (arrangement pattern information) of the brightness determination unit 122. At this time, the arithmetic unit 123 calculates the offset to remove the effects caused by the reversal of the arrangement pattern of the first moiré mark Mm1 and / or the arrangement pattern of the second moiré mark Mm2. The offset information including the offset calculated in this way can be used for a variety of applications. The offset information can be used, for example, in a quality evaluation device for evaluating the quality of the manufactured semiconductor device 1, an alignment device for adjusting the position of the substrate 11 in the manufacturing process of the semiconductor device 1, and the like.

[0064] Hereinafter, other embodiments will be described with reference to the accompanying drawings, but sometimes the same reference numerals are used to mark the same or identical parts as in the first embodiment and their descriptions are omitted.

[0065] (Second Implementation)

[0066] Figure 12 This is a flowchart illustrating an example of the processing in the measurement method according to the second embodiment. The measurement method according to the first embodiment ( Figure 9 In the previous method, the brightness and darkness measurement step was performed before the moiré fringe measurement step. However, in the measurement method of this embodiment, the brightness and darkness measurement step is performed after the moiré fringe measurement step.

[0067] The measurement method in this embodiment is similar to that in the measurement method in the first embodiment. First, a mark position detection step (S301) is performed to detect the positions of the first mark M1 and the second mark M2. Then, a moiré fringe measurement step (S302) is performed to measure the moiré fringes generated by the overlap of the first moiré mark Mm1 and the second moiré mark Mm2.

[0068] Then, a brightness determination step (S303) is performed to determine the brightness of the arrangement pattern for at least one of the first moiré mark Mm1 and the second moiré mark Mm2. At this time, similar to the first embodiment, the arrangement pattern of the first moiré mark Mm1 is determined based on the imaging data of the first reference mark Ms1, and the arrangement pattern of the second moiré mark Mm2 is determined based on the imaging data of the second reference mark Ms2.

[0069] Then, the offset calculation step (S304) of the offset (distance ΔD) between the first layer 12 (first moiré mark Mm1) and the second layer 13 (second moiré mark Mm2) is performed based on the measurement results (moiré fringe information) of the moiré fringe measurement step and the determination results (arrangement pattern information) of the brightness determination step. At this time, the offset is calculated based on the arrangement pattern information so that the effect of the inversion of the arrangement pattern of the first moiré mark Mm1 and / or the second moiré mark Mm2 is removed.

[0070] Figure 13 This is a flowchart illustrating an example of the moiré fringe measurement process according to the second embodiment. When the offset calculation step (S304) is started, the arrangement pattern information generated by the brightness determination step (S303) is obtained (S401). Furthermore, the offset is calculated based on the moiré fringe information generated by the moiré fringe measurement step (S302) (S402).

[0071] Then, it is determined whether the first arrangement pattern is a reversed pattern (S403). If the first arrangement pattern is a reversed pattern (S403: Yes), it is further determined whether the second arrangement pattern is a reversed pattern (S404). If the second arrangement pattern is a reversed pattern (S404: Yes), the offset is corrected to remove the influence of both the first and second arrangement patterns being reversed patterns (S405). In step S404, if the second arrangement pattern is not a reversed pattern (S404: No), the offset is corrected to remove the influence of only the first arrangement pattern being a reversed pattern (S406).

[0072] In step S403, if the first arrangement pattern is not a reversed pattern (S403: No), it is determined whether the second arrangement pattern is a reversed pattern (S407). In step S407, if the second arrangement pattern is a reversed pattern (S407: Yes), the offset is corrected to remove the influence of only the second arrangement pattern being a reversed pattern (S408). In step S407, if the second arrangement pattern is not a reversed pattern (S407: No), since both the first and second arrangement patterns are normal patterns, the moiré fringe information is not corrected (S409).

[0073] As described above, even if the brightness determination step is performed after the moiré fringe measurement step, the effect caused by the reversal of the arrangement pattern of the first moiré mark Mm1 and / or the second moiré mark Mm2 can be removed, and the offset between the first layer 12 and the second layer 13 can be measured with high precision.

[0074] (Third Implementation)

[0075] Figure 14 This diagram schematically illustrates an example of the manufacturing process of the semiconductor device 1 according to the third embodiment. The semiconductor device 1 according to this embodiment is manufactured using an imprinting method. The manufacturing process of the semiconductor device 1 according to this embodiment includes the following steps: forming a predetermined pattern on the upper surface of the workpiece 51 by contacting the exposure area 55 of the template 52 with the upper surface of the workpiece 51 formed on the substrate 11. The template 52 is formed of a light-transmitting material.

[0076] In this embodiment, a technique for measuring the offset between the workpiece 51 and the template 52 will be described. Marks (first mark and second mark described later) for measuring the offset between the workpiece 51 and the template 52 are formed on both.

[0077] Figure 15 This is a top view showing an example of the configuration of the first reference numeral M1 involved in the third embodiment. Figure 16 This is a top view illustrating an example of the configuration of the second mark M2 according to the third embodiment. The first mark M1 is formed on the upper surface of the workpiece 51, for example, in an area outside the area contacted by the exposure area 55 of the template 52. The second mark M2 is formed on the lower surface of the template 52, for example, in an area outside the exposure area 55.

[0078] like Figure 15 As shown, the first mark M1 involved in this embodiment includes a first moiré mark Mm1 and a first reference mark Ms1 having the same function as in the first embodiment. The first moiré mark Mm1 is used to communicate with the second moiré mark Mm2 described later. Figure 16 The markings that produce moiré fringes are formed by the overlap of the two parts, including multiple bright areas B1 and multiple dark areas D1. The specific formation of the bright areas B1 and dark areas D1 should be appropriately selected based on the configuration of the semiconductor device 1. For example, the bright areas B1 can be formed from regions containing metals such as tungsten, and the dark areas D1 can be formed from regions without metals (exposed areas such as silicon oxide film). The first reference mark Ms1 involved in this embodiment has optical properties corresponding to the bright areas B1 of the first moiré mark Mm1 and is formed from the same material as the bright areas B1. The first reference mark Ms1 can also be used for preliminary coarse alignment of the workpiece 51 and the template 52.

[0079] like Figure 16 As shown, the second marker M2 involved in this embodiment includes a second moiré marker Mm2 and a second reference marker Ms2 having the same function as in the second embodiment. The second moiré marker Mm2 is used to communicate with the first moiré marker Mm1 ( Figure 15 The overlapping of the two moiré marks creates a moiré fringe, comprising multiple bright areas B2 and multiple dark areas D2. The specific formation of the bright areas B2 and dark areas D2 should be appropriately selected based on the configuration of the template 52. For example, the bright areas B2 can be formed from regions containing metal such as tungsten, and the dark areas D1 can be formed from regions without metal (formed from quartz, etc.). The second reference mark Ms2 in this embodiment has optical properties corresponding to the bright areas B2 of the second moiré mark Mm2 and is formed from the same material as the bright areas B2. The second reference mark Ms2 can also be used for preliminary coarse alignment of the workpiece 51 and the template 52.

[0080] As described above, by forming a first mark M1 on the workpiece 51 and a second mark M2 on the template 52, and performing the measurement method in the same manner as in the first embodiment, the influence caused by the reversal of the arrangement pattern of the first moiré mark Mm1 and / or the second moiré mark Mm2 can be removed, and the offset between the workpiece 51 and the template 52 can be measured with high precision.

[0081] (Fourth implementation)

[0082] Figure 17 This diagram illustrates an example of the configuration of the first marker M1 and the second marker M2 used in the measurement method according to the fourth embodiment. This embodiment relates to a technique for measuring the offset between the first layer 12 and the second layer 13 of the semiconductor device 1 in the same way as the first embodiment, but differs from the first embodiment in that it does not utilize moiré fringes.

[0083] like Figure 17 As shown in the upper left portion, the first mark M1 formed in the first layer 12 (e.g., the scribe line region 22) in this embodiment includes a first alignment mark Mi1 and a first reference mark Ms1. The first alignment mark Mi1 is constructed by alternatingly arranging a plurality of bright portions B1 and a plurality of dark portions D1 extending along the Y direction at predetermined intervals along the X-axis direction. The first reference mark Ms1 has optical characteristics corresponding to the bright portions B1. With this configuration, the arrangement pattern of the bright portions B1 and dark portions D1 in the first alignment mark Mi1 can be determined based on the imaging data of the first reference mark Ms1, just as in the first embodiment.

[0084] like Figure 17As shown in the upper right part, the second mark M2 formed on the second layer 13 (e.g., the scribe line region 22) according to this embodiment includes a second alignment mark Mi2 and a second reference mark Ms2. The second alignment mark Mi2 is formed by alternating bright parts B2 and dark parts D2 extending along the Y-axis at the same spacing as the first alignment mark Mi1 along the X-axis direction. The second reference mark Ms2 has optical characteristics corresponding to the bright parts B2. With this configuration, the arrangement pattern of bright parts B2 and dark parts D2 in the second alignment mark Mi2 can be determined based on the imaging data of the second reference mark Ms2, just as in the first embodiment. In addition, a first opening 71 and a second opening 72 are provided on the second mark M2. The first opening 71 is formed in the region corresponding to the formation position of the first alignment mark Mi1 when the second layer 13 is formed on the first layer 12. The second opening 72 is formed in the region corresponding to the formation position of the first reference mark Ms1 when the second layer 13 is formed on the first layer 12. With this configuration, the first alignment mark Mi1 and the first reference mark Ms1 can be observed from above the second layer 13 after the second layer 13 is formed on the first layer 12.

[0085] exist Figure 17 The lower part illustrates a state where the first layer 12 and the second layer 13 are stacked without offset. At this time, the bright portion B1 and dark portion D1 of the first alignment mark Mi1 and the bright portion B2 and dark portion D2 of the second alignment mark Mi2 are aligned in a straight line along the Y-axis. By analyzing whether the positional relationship between the first alignment mark Mi1 and the second alignment mark Mi2 is in such a state based on shooting data after the formation of the second layer 13, the offset between the first layer 12 and the second layer 13 can be measured. Furthermore, similar to the first embodiment, the arrangement pattern of the first alignment mark Mi1 can be determined based on the shooting data of the first reference mark Ms1, and the arrangement pattern of the second alignment mark Mi2 can be determined based on the shooting data of the second reference mark Ms2. Therefore, even without utilizing moiré fringes, the influence caused by the reversal of the arrangement patterns of the bright and dark portions can be eliminated, and the offset between multiple layers can be measured with high precision.

[0086] Furthermore, the configuration of the fourth embodiment, like that of the third embodiment, can also be applied to the measurement of the offset between the workpiece 51 and the template 52.

[0087] Programs that enable a computer to perform the various processes and functions described in the above embodiments are provided as files in an installable or executable form, stored on computer-readable recording media such as CD-ROM, floppy disk (FD), CD-R, or DVD (Digital Versatile Disk). Alternatively, the program can be stored on a computer connected to a network such as the Internet and provided by downloading it via the network. Alternatively, the program can be provided or distributed via a network such as the Internet. Alternatively, the program can be pre-loaded into ROM or the like.

[0088] Several embodiments of the present invention have been described, but these embodiments are merely illustrative and not intended to limit the scope of the invention. These new embodiments can be implemented in a wide variety of other ways, and various omissions, substitutions, or modifications can be made without departing from the spirit of the invention. These embodiments and / or variations thereof are included within the scope and spirit of the invention, and are included within the scope of the invention as described in the claims and its equivalents.

Claims

1. A method for determination, comprising: After the second layer is formed on the first layer, marker position information representing the relative positional relationship between the first alignment marker and the second alignment marker is generated. The first alignment marker is formed on the first layer and includes bright and dark areas, and the second alignment marker is formed on the second layer and includes bright and dark areas. Based on the imaging data of the reference markers, at least one of the first alignment pattern and the second alignment pattern is determined. The reference markers are formed in regions different from the regions where the first alignment mark and the second alignment mark are formed. The first alignment pattern represents the arrangement pattern of the bright and dark parts of the first alignment mark, and the second alignment pattern represents the arrangement pattern of the bright and dark parts of the second alignment mark. Based on at least one of the first arrangement pattern and the second arrangement pattern, as well as the mark position information, the offset between the first layer and the second layer is calculated. The reference mark includes a first reference mark, which is formed in the first layer at a position that is a predetermined distance away from the first alignment mark. The first reference mark has optical properties corresponding to either the bright or dark portion of the first alignment mark.

2. The determination method according to claim 1, The predetermined distance is less than 20 μm.

3. The determination method according to claim 1 or 2, The first alignment mark is formed by alternating arrangement of a plurality of bright portions and a plurality of dark portions extending along a first direction along a second direction intersecting the first direction, wherein the width of the first reference mark in the second direction is greater than the width of the bright portion of the first alignment mark in the second direction and the width of the dark portion of the first alignment mark in the second direction.

4. The determination method according to claim 3, The width of the first reference mark in the second direction is 1.5 μm or more.

5. The determination method according to claim 4, A blank area with different optical properties from the first reference mark is provided around the first reference mark, and the width of the blank area in the second direction is more than 1.5 μm.

6. The determination method according to claim 1 or 2, Before generating the marker position information, at least one of the first arrangement pattern and the second arrangement pattern is determined.

7. The determination method according to claim 1 or 2, After generating the marker position information, at least one of the first arrangement pattern and the second arrangement pattern is determined.

8. The determination method according to claim 1 or 2, The marker position information is generated based on moiré fringes produced by illuminating the area where the first alignment marker and the second alignment marker overlap in the stacking direction.

9. A method for determination, comprising: When the workpiece comes into contact with the template, mark position information indicating the relative positional relationship between the first alignment mark and the second alignment mark is generated. The template transfers a predetermined pattern onto the workpiece by contacting it. The first alignment mark is formed on the workpiece and includes bright and dark areas, and the second alignment mark is formed on the template and includes bright and dark areas. Based on the imaging data of the reference markers, at least one of the first alignment pattern and the second alignment pattern is determined. The reference markers are formed in regions different from the regions where the first alignment mark and the second alignment mark are formed. The first alignment pattern represents the arrangement pattern of the bright and dark parts of the first alignment mark, and the second alignment pattern represents the arrangement pattern of the bright and dark parts of the second alignment mark. Based on at least one of the first arrangement pattern and the second arrangement pattern, as well as the mark position information, the offset between the processed part and the template is calculated. The reference mark includes a first reference mark, which is formed in the workpiece at a position that is a predetermined distance away from the first alignment mark. The first reference mark has optical properties corresponding to either the bright or dark portion of the first alignment mark.

10. A measuring device comprising: The marker measuring unit, after forming a second layer on a first layer, generates marker position information indicating the relative positional relationship between a first alignment marker and a second alignment marker. The first alignment marker is formed on the first layer and includes a bright area and a dark area, and the second alignment marker is formed on the second layer and includes a bright area and a dark area. The brightness and darkness determination unit determines at least one of a first alignment pattern and a second alignment pattern based on the shooting data of the reference mark. The reference mark is formed in a region different from the region where the first alignment mark is formed and the region where the second alignment mark is formed. The first alignment pattern represents the arrangement pattern of the bright and dark parts of the first alignment mark, and the second alignment pattern represents the arrangement pattern of the bright and dark parts of the second alignment mark. as well as The calculation unit calculates the offset between the first layer and the second layer based on at least one of the first arrangement pattern and the second arrangement pattern, as well as the mark position information. The reference mark includes a first reference mark, which is formed in the first layer at a position that is a predetermined distance away from the first alignment mark. The first reference mark has optical properties corresponding to either the bright or dark portion of the first alignment mark.

11. A measuring device comprising: The marking measuring unit generates marking position information indicating the relative positional relationship between a first alignment mark and a second alignment mark when the workpiece is brought into contact with the template. The template transfers a predetermined pattern onto the workpiece by contacting it. The first alignment mark is formed on the workpiece and includes a bright area and a dark area. The second alignment mark is formed on the template and includes a bright area and a dark area. The brightness and darkness determination unit determines at least one of a first alignment pattern and a second alignment pattern based on the shooting data of the reference mark. The reference mark is formed in a region different from the region where the first alignment mark is formed and the region where the second alignment mark is formed. The first alignment pattern represents the arrangement pattern of the bright and dark parts of the first alignment mark, and the second alignment pattern represents the arrangement pattern of the bright and dark parts of the second alignment mark. as well as The calculation unit calculates the offset between the processed part and the template based on at least one of the first arrangement pattern and the second arrangement pattern, as well as the mark position information. The reference mark includes a first reference mark, which is formed in the workpiece at a position that is a predetermined distance away from the first alignment mark. The first reference mark has optical properties corresponding to either the bright or dark portion of the first alignment mark.

12. A mark formed on a layer constituting a semiconductor device, comprising: Region 1, which includes multiple bright areas and multiple dark areas; and A reference mark, formed in a region different from the first region, has optical properties corresponding to either the bright part or the dark part.

13. The marking according to claim 12, The distance between the first region and the reference mark is less than 20 μm.

14. The marking according to claim 12 or 13, The plurality of bright portions and the plurality of dark portions extend along a first direction and are alternately arranged along a second direction intersecting the first direction, wherein the width of the reference mark in the second direction is greater than the width of the bright portions in the second direction and the width of the dark portions in the second direction.

15. The marking according to claim 14, The width of the reference mark in the second direction is 1.5 μm or more.

16. The marking according to claim 15, A blank area with different optical properties from the reference mark is provided around the reference mark, and the width of the blank area in the second direction is more than 1.5 μm.

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