Method and apparatus for measuring defects in etched holes

Abstract

This disclosure discloses a method and apparatus for measuring defects in etched holes. The method involves etching a target monitoring sheet to form a monitoring hole, then planarizing the target monitoring sheet to a set monitoring height, and then acquiring a monitoring image of the side of the target monitoring sheet with the monitoring hole at the set monitoring height. Based on the perimeter of the fitted shape of the monitoring hole in the monitoring image, the target defect measurement value is determined, thereby measuring the defect value of the monitoring hole at the set monitoring height. This method can measure and quantify vertical stripe-like defects.

Description

Technical Field

[0001] This disclosure relates to the field of semiconductor technology, and in particular to a method and apparatus for measuring defects in etched holes. Background Technology

[0002] With the development of semiconductor technology, traditional two-dimensional packaging can no longer meet the needs of the industry. Therefore, vertical interconnect stacked packaging based on substrate through-hole technology, such as through silicon via (TSV) technology, has gradually led the trend of packaging technology development with its key technological advantages of short-distance interconnection and high-density integration.

[0003] A common defect in via etching is vertical striation on the sidewalls of the via, which is more pronounced in the upper part of the via. This can easily lead to poor coating (i.e., incomplete photoresist coating during silicon wafer exposure), and consequently, copper plating can diffuse into the silicon wafer. However, currently, there is no method to measure and quantify this vertical striation defect on the sidewalls of vias, making it increasingly difficult to control the morphology of via etching. Summary of the Invention

[0004] The present disclosure provides a method and apparatus for measuring defects in etched holes, which are used to measure vertical stripe-like defects in through holes.

[0005] According to some embodiments, a first aspect of this disclosure provides a method for measuring defects in etched holes, including:

[0006] Obtain a target monitoring sheet, which has multiple monitoring holes of M different aperture sizes. The target monitoring holes are formed by etching, where M is an integer greater than 0. The monitoring holes are divided into upper, middle, and lower parts according to their depth from shallow to deep.

[0007] The target monitoring panel is flattened to a set monitoring height, which is located above the monitoring hole.

[0008] Acquire a monitoring image of the target monitoring panel at the set monitoring height, on the side with the monitoring hole;

[0009] The target defect measurement value is determined based on the perimeter of the fitted shape of the monitoring hole with the M aperture sizes in the monitoring image.

[0010] In this embodiment, a monitoring hole is formed by etching the target monitoring sheet, and then the target monitoring sheet is planarized to a set monitoring height. A monitoring image of the side of the target monitoring sheet with the monitoring hole at the set monitoring height is obtained. The perimeter of the fitted shape of the monitoring hole in the monitoring image is used to determine the target defect measurement value. The defect measurement value of the monitoring hole at the set monitoring height can be measured and quantified to achieve vertical stripe defects.

[0011] In some possible implementations, before flattening the target monitoring image to a set monitoring height, the method further includes:

[0012] The monitoring hole is filled with a medium material, which is different from the material of the target monitoring sheet.

[0013] In some possible implementations, determining the target defect measurement value based on the perimeter of the fitted shape of the target monitoring hole with the M aperture sizes in the monitoring image includes:

[0014] From the M aperture sizes in the monitoring image, determine N target monitoring holes corresponding to each aperture size; where N is an integer greater than 0.

[0015] Calculate the perimeter of the fitted shape for each of the N target monitoring holes of the M aperture sizes;

[0016] The target defect measurement value is determined based on the perimeter of the fitted shape of each of the N target monitoring holes of the M apertures.

[0017] In some possible implementations, determining the target defect measurement value based on the perimeter of the fitted shape of each of the N target monitoring holes of the M aperture sizes includes:

[0018] Based on the perimeter of the fitted shape of the nth target monitoring hole among the N target monitoring holes of the M apertures, the nth initial defect measurement value is determined; n is an integer and 1≤n≤N;

[0019] Determine the predicted average value from the first initial defect measurement value to the Nth initial defect measurement value, and determine the predicted average value as the target defect measurement value.

[0020] In some possible implementations, determining the nth initial defect measurement value based on the perimeter of the fitted shape of the nth target monitoring hole among the N target monitoring holes of the M aperture sizes includes:

[0021] The nth initial defect measurement value is determined based on the difference between the perimeter of the fitted shape of the nth target monitoring hole and the corresponding design perimeter among the N target monitoring holes of the M apertures.

[0022] In some possible implementations, the holes of the M diameters are divided into holes of diameter 1 to diameter M, in ascending order of hole diameter.

[0023] The following formula is used to determine the nth initial defect measurement value based on the difference between the perimeter of the fitted shape of the nth target monitoring hole and the corresponding design perimeter among the N target monitoring holes of the M apertures.

[0024]

[0025] Among them, S n R represents the nth initial defect measurement value. m C represents the similarity ratio of the shape of the monitoring hole with diameter m to the shape of the monitoring hole with diameter 1. mn C represents the perimeter of the fitted shape of the nth target monitoring hole among the monitoring holes of the mth aperture. m-design Let m represent the design perimeter of the monitoring hole with the m-th aperture, where m is an integer and 1 ≤ m ≤ M.

[0026] In some possible implementations,

[0027] The following formula is used to determine the nth initial defect measurement value based on the difference between the perimeter of the fitted shape of the nth target monitoring hole and the corresponding design perimeter among the N target monitoring holes of the M apertures.

[0028]

[0029] Among them, S n Z represents the nth initial defect measurement value, Z1 represents the diameter of the monitoring hole of the first aperture, Z m C represents the diameter of the monitoring hole with diameter m. mn The perimeter represents the fitted shape of the nth target monitoring hole among the monitoring holes of the mth aperture.

[0030] In some possible implementations, the predicted average value of the first initial defect measurement to the Nth initial defect measurement is determined using the following formula;

[0031]

[0032] Among them, S n This represents the nth initial defect measurement value. Represents the predicted average value, and determines The measured value of the target defect.

[0033] In some possible implementations, calculating the perimeter of the fitted shape for each of the N target monitoring holes with different apertures includes:

[0034] Fitting determines the closed regular pattern formed by the outermost vertices of each of the N target monitoring holes with different apertures;

[0035] Based on the closed regular pattern corresponding to each of the N target monitoring holes with different apertures and the perimeter calculation formula corresponding to the closed regular pattern, the perimeter of the fitted shape of each of the N target monitoring holes with different apertures is determined.

[0036] In some possible implementations, the closed regular shape includes at least one of a circle, an ellipse, and a polygon.

[0037] According to some embodiments, a second aspect of this disclosure provides a method for monitoring an etching cavity, including:

[0038] Using the above-described method for measuring defects in etched holes, the target defect measurement value is determined;

[0039] Determine whether the measured value of the target defect exceeds the set threshold range;

[0040] If so, it is determined that the etching cavity is in an abnormal working state during the current monitoring cycle;

[0041] If not, then it is determined that the etching cavity is in normal working condition during the current monitoring cycle.

[0042] The method for measuring defects in etched holes provided in this disclosure involves etching a target monitoring sheet to form a monitoring hole, then planarizing the target monitoring sheet to a set monitoring height. A monitoring image of the side of the target monitoring sheet with the monitoring hole at the set monitoring height is acquired. Based on the perimeter of the fitted shape of the monitoring hole in the monitoring image, the measurement value of the target defect is determined, thus measuring and quantifying the defect value of the monitoring hole at the set monitoring height. By comparing the target defect measurement value with a set threshold range, anomalies can be detected promptly, thereby monitoring the stability of the etching cavity. Furthermore, this disclosure also reduces the influence of hole size on the vertical stripe defects of the monitoring hole by setting multiple monitoring holes with different diameters.

[0043] In some possible implementations, the method for determining the set threshold range includes:

[0044] In each of the Y sequentially executed detection cycles, the first and second detection defect measurement values ​​corresponding to the detection sheet are obtained; wherein, the detection sheet has multiple detection holes of at least one aperture, the detection holes are formed by etching, and the detection holes are divided into upper, middle and lower parts according to depth from shallow to deep; the first detection defect measurement value is determined when the detection sheet is planarized to a first detection set height, and the second detection defect measurement value is determined when the detection sheet is planarized to a second detection set height; the first detection set height is the middle part of the detection hole, and the second detection set height is the lower part of the detection hole;

[0045] The detection threshold and detection threshold error are determined based on the first and second detection defect measurement values ​​in the Y detection cycles.

[0046] The set threshold range is determined based on the detection threshold and the detection threshold error.

[0047] In some possible implementations, obtaining the first and second detection defect measurements corresponding to the detection piece in each of the Y sequentially executed detection cycles includes:

[0048] The detection piece is formed during the y-th detection cycle of the Y detection cycles;

[0049] The detection piece is flattened to the first detection set height;

[0050] Acquire a first detection image of the side of the detection plate with the detection hole at the first detection set height;

[0051] Based on the perimeter of the fitted shape of the selected detection hole of the M apertures in the first detection image, the first detection defect measurement value corresponding to the y-th detection cycle is determined;

[0052] The detection piece that has been flattened to the first detection set height is further flattened to the second detection set height.

[0053] Acquire a second detection image of the target monitoring film at the second detection set height, on the side with the detection hole;

[0054] Based on the perimeter of the fitted shape of the selected detection hole of the M apertures in the second detection image, the second detection defect measurement value corresponding to the y-th detection cycle is determined.

[0055] In some possible implementations, determining the first detection defect measurement value corresponding to the y-th detection cycle based on the perimeter of the fitted shape of the selected detection hole of the M apertures in the first detection image includes:

[0056] From the M aperture detection holes in the first detection image, determine K first target detection holes corresponding to each aperture size; where K is an integer greater than 0;

[0057] Calculate the perimeter of the fitted shape of each of the K first target detection holes of the M aperture sizes;

[0058] Based on the perimeter of the fitted shape of each of the K first target detection holes of the M apertures, the first detection defect measurement value corresponding to the y-th detection cycle is determined.

[0059] In some possible implementations, determining the second detection defect measurement value corresponding to the y-th detection cycle based on the perimeter of the fitted shape of the selected detection aperture of the M aperture sizes in the second detection image includes:

[0060] From the M aperture detection holes in the second detection image, determine K second target detection holes corresponding to each aperture size; where K is an integer greater than 0;

[0061] Calculate the perimeter of the fitted shape of each of the K second target detection holes of the M aperture sizes;

[0062] Based on the perimeter of the fitted shape of each of the K second target detection holes of the M apertures, the second detection defect measurement value corresponding to the y-th detection cycle is determined.

[0063] In some possible implementations, the set threshold range is j is an integer greater than 0. σ represents the detection threshold, and σ represents the detection threshold error.

[0064] According to some embodiments, a third aspect of this disclosure provides a defect measuring device for etched holes, comprising:

[0065] A planarization processing device is configured to acquire a target monitoring sheet and planarize the target monitoring sheet to a set monitoring height. The target monitoring sheet has multiple monitoring holes of M different apertures, which are formed by etching, where M is an integer greater than 0. The monitoring holes are divided into upper, middle, and lower parts according to their depth from shallow to deep, and the set monitoring height is located at the upper part of the monitoring holes.

[0066] An image acquisition device is configured to acquire a monitoring image of the side of the target monitoring panel at the set monitoring height that has the monitoring hole.

[0067] The defect measurement device is configured to determine the target defect measurement value based on the perimeter of the fitted shape of the monitoring hole of the M aperture sizes in the monitoring image.

[0068] According to some embodiments, a fourth aspect of this disclosure provides a monitoring device for an etching cavity, including:

[0069] A planarization processing device is configured to acquire a target monitoring sheet and planarize the target monitoring sheet to a set monitoring height. The target monitoring sheet has multiple monitoring holes of M different apertures, which are formed by etching, where M is an integer greater than 0. The monitoring holes are divided into upper, middle, and lower parts according to their depth from shallow to deep, and the set monitoring height is located at the upper part of the monitoring holes.

[0070] An image acquisition device is configured to acquire a monitoring image of the side of the target monitoring panel at the set monitoring height that has the monitoring hole.

[0071] The defect measurement device is configured to determine the target defect measurement value based on the perimeter of the fitted shape of the monitoring hole of the M aperture sizes in the monitoring image;

[0072] The data processing device is configured to determine whether the measured value of the target defect exceeds a set threshold range; if so, it determines that the etching cavity is in an abnormal working state in the current monitoring cycle; if not, it determines that the etching cavity is in a normal working state in the current monitoring cycle. Attached Figure Description

[0073] Figure 1 This is a schematic diagram of a vertical stripe-like defect on the sidewall in an embodiment of this disclosure;

[0074] Figure 2 This is a flowchart of a method for measuring defects in etched holes according to an embodiment of this disclosure;

[0075] Figure 3a These are some top-view structural diagrams of the target monitoring film in the embodiments of this disclosure;

[0076] Figure 3b for Figure 3a The diagram shows a cross-sectional view of the target monitoring image along the AA' direction.

[0077] Figure 4a These are some other top-view structural diagrams of the target monitoring film in the embodiments of this disclosure;

[0078] Figure 4b for Figure 4aThe diagram shows a cross-sectional view of the target monitoring image along the AA' direction.

[0079] Figure 5 This is a cross-sectional view of the target monitoring patch in an embodiment of this disclosure when it is flattened to the set monitoring height.

[0080] Figure 6a This is a schematic diagram of a monitoring image when the target monitoring patch is flattened to the set monitoring height in an embodiment of this disclosure;

[0081] Figure 6b This is a schematic diagram of the target monitoring hole when the target monitoring sheet is flattened to the set monitoring height in an embodiment of this disclosure;

[0082] Figure 7 This is a flowchart of the monitoring method for the etching cavity in the embodiments of this disclosure;

[0083] Figure 8 This is a flowchart of a method for determining a set threshold range in an embodiment of this disclosure;

[0084] Figure 9a These are some top view structural diagrams of the detection piece in the embodiments of this disclosure;

[0085] Figure 9b for Figure 9a The diagram shows a cross-sectional view of the test piece along the AA' direction;

[0086] Figure 10a These are some other top view structural schematic diagrams of the detection piece in the embodiments of this disclosure;

[0087] Figure 10b for Figure 10a The diagram shows a cross-sectional view of the test piece along the AA' direction;

[0088] Figure 11 This is a cross-sectional view of the detection piece when it is flattened to the first detection set height in an embodiment of this disclosure.

[0089] Figure 12a This is a schematic diagram of the first detection image when the detection patch is flattened to a first detection set height in an embodiment of this disclosure;

[0090] Figure 12b This is a schematic diagram of the first target detection hole when the detection piece is flattened to the first detection set height in an embodiment of this disclosure;

[0091] Figure 13 This is a cross-sectional view of the detection piece when it is flattened to the second detection set height in an embodiment of this disclosure.

[0092] Figure 14aThis is a schematic diagram of the first detection image when the detection patch is flattened to the second detection set height in an embodiment of this disclosure;

[0093] Figure 14b This is a schematic diagram of the second target detection hole when the detection piece is flattened to the second detection set height in an embodiment of this disclosure. Detailed Implementation

[0094] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure. Furthermore, the embodiments and features in the embodiments of this disclosure can be combined with each other without conflict. All other embodiments obtained by those skilled in the art based on the described embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.

[0095] Unless otherwise defined, the technical or scientific terms used in this disclosure shall have the ordinary meaning understood by one of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” and similar terms used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as “comprising” or “including” mean that an element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as “connected” or “linked” are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect.

[0096] It should be noted that the dimensions and figures in the accompanying drawings do not reflect actual scale and are intended only to illustrate the content of this disclosure. Furthermore, the same or similar reference numerals are used throughout to denote the same or similar elements or elements having the same or similar functions.

[0097] Vias, serving as convenient channels for connecting multiple wafers, play an increasingly important role in vertical interconnect stack-up packaging processes. Currently, the mainstream method for etching vias is through an etching machine. During this etching process, vertical stripes (such as those caused by high-energy bombardment damaging the sidewalls of the vias) appear on the sidewalls. Figure 1 (As shown) defects. However, currently, there is no method available to measure and quantify the sidewall striation defects appearing in the connector holes, making it increasingly difficult to control the etching morphology of the connector holes.

[0098] This disclosure provides a method for measuring defects in etched holes, specifically for measuring vertical stripe-like defects in the holes.

[0099] In this embodiment, the working process of multiple monitoring cycles can be executed sequentially at determined intervals. This allows for periodic monitoring of whether the formed monitoring holes have defects, and consequently, periodic monitoring of the stability of the etching cavity of the etching holes.

[0100] For example, in this embodiment of the disclosure, the defect in the monitoring hole formed by monitoring can be a vertical stripe-like defect in the through hole. Of course, in specific implementation, the defect in the monitoring hole formed by monitoring can also be other types of defects, which can be determined according to the needs of the actual application environment, and are not limited here.

[0101] like Figure 2 As shown, the defect measurement method for etched holes provided in this embodiment may include the following steps:

[0102] S110, Obtain the target surveillance footage.

[0103] For example, the target monitoring sheet has multiple monitoring holes of M different aperture sizes formed by etching, where M is an integer greater than 0. That is, the target monitoring sheet has one or more monitoring holes of different aperture sizes. For example, the M aperture sizes are divided into monitoring holes of aperture 1 to aperture 1M, in ascending order of aperture size. Thus, multiple monitoring holes of aperture 1, multiple monitoring holes of aperture 2, multiple monitoring holes of aperture 3, ..., multiple monitoring holes of aperture 1M are etched into the target monitoring sheet. In actual processes, the larger the aperture, the more obvious the defects. This embodiment of the present disclosure reduces the influence of aperture size on vertical stripe defects in the monitoring holes by setting multiple monitoring holes of different aperture sizes.

[0104] It should be noted that the ideal shape of the monitoring hole formed by etching in this embodiment includes, but is not limited to, circles and rectangles. Furthermore, the diameter of the monitoring hole is the diameter of the ideal shape (circle in this embodiment). That is, the diameter refers to the diameter determined during the process fabrication design, not the actual diameter of the fabricated monitoring hole. Additionally, the design perimeter is the perimeter of the monitoring hole calculated based on the diameter determined during the process fabrication design.

[0105] This disclosure does not limit the specific value of each of the M aperture sizes. For example, taking M=3, the first aperture can be 2µm, the second aperture can be 4µm, and the third aperture can be 8µm.

[0106] In this embodiment of the disclosure, the depth of each monitoring hole formed by etching in the target monitoring chip is H. This embodiment of the disclosure does not limit the specific value of H. Exemplarily, H is 40µm to 60µm. For example, H can be 40µm, 50µm, or 60µm.

[0107] It should be noted that due to manufacturing processes, the depth of different monitoring holes may vary slightly. As long as the depth of the monitoring hole is H within the allowable error range, it is acceptable.

[0108] In some examples, the monitoring aperture is filled with a dielectric material that is different from the material of the target monitoring chip; for example, the dielectric material includes, but is not limited to, oxides.

[0109] For example, forming a target surveillance video may include the following steps:

[0110] First, multiple monitoring holes of M different apertures are etched into the initial monitoring chip. For example, as shown... Figure 3a and Figure 3b As shown, an initial monitoring wafer 1 is obtained. No other semiconductor devices or structures are fabricated on this initial monitoring wafer 1, and its surface impurities are removed through a specific cleaning process. The cleaned initial monitoring wafer 1 is placed in an etching chamber (e.g., a plasma etching chamber), and three aperture sizes are selected: a first aperture of 2µm, a second aperture of 4µm, and a third aperture of 8µm. Multiple monitoring holes with a depth of H (2µm, 4µm, and 8µm) are formed on the initial monitoring wafer 1, respectively. Monitoring holes of the same aperture size are placed in the same region. For example, the monitoring holes in region 21 have a diameter of 2µm, the monitoring holes in region 22 have a diameter of 4µm, and the monitoring holes in region 23 have a diameter of 8µm.

[0111] For example, the monitoring hole in this application can be a hole that does not penetrate the initial monitoring film. Of course, the monitoring hole in this application can also be a hole that penetrates the initial monitoring film, and this is not limited here.

[0112] Next, a dielectric material is coated onto the initial monitoring sheet with the monitoring holes formed therein, and the dielectric material fills each of the plurality of monitoring holes. For example, as shown... Figure 4a and Figure 4b As shown, oxide 3 is coated on the entire side of the initial monitoring sheet 1 where the monitoring holes are formed, and the oxide 3 completely fills each monitoring hole with a diameter of 2 μm, the oxide completely fills each monitoring hole with a diameter of 4 μm, and the oxide completely fills each monitoring hole with a diameter of 8 μm.

[0113] Alternatively, the oxide may include, but is not limited to, silicon oxide.

[0114] This application does not limit the material of the initial monitoring chip. Exemplarily, the initial monitoring chip can be made of a semiconductor material. For example, the initial monitoring chip can be a silicon wafer, in which case the formed monitoring via can be a through-silicon via (TSV). Alternatively, the initial monitoring chip can also be made of other semiconductor materials, such as sapphire.

[0115] S120. Flatten the target monitoring image to the set monitoring height.

[0116] In some examples, the target surveillance video is flattened to the set monitoring height, including: Figure 5 As shown, the target monitoring sheet 1 coated with oxide is planarized through a polishing process, and the planarization process is stopped when the monitoring set height is reached.

[0117] This disclosure does not limit the polishing process. Exemplarily, the polishing process used in the embodiments of this disclosure can be chemical mechanical polishing (CMP).

[0118] In this embodiment of the disclosure, the monitoring hole is divided into upper, middle and lower parts according to the depth from shallow to deep.

[0119] This disclosure does not limit the monitoring setting height. Exemplarily, the monitoring setting height is the upper part of the monitoring hole. For example, the monitoring setting height in the embodiments of this disclosure can range from 0.7H to 0.8H. For example, the monitoring setting height can be 0.7H, 0.75H, or 0.8H. When the monitored defect is a sidewall vertical stripe defect, since the sidewall vertical stripe defect is more obvious at the upper part of the hole, and as the etching cavity is used for longer, the morphology at the upper part of the hole will deteriorate, and the sidewall vertical stripe defects at the upper part of the hole will also increase. Therefore, setting the monitoring setting height at the upper part of the monitoring hole allows for better monitoring and measurement of defects.

[0120] S130: Obtain the monitoring image of the target monitoring film with the monitoring hole at the set monitoring height.

[0121] In some examples, a target monitoring film, flattened to a set monitoring height, can be placed in a Critical Dimension Scanning Electron Microscope (CDSEM). CDSEM is then used to acquire a monitoring image of the side of the target monitoring film with the monitoring aperture, such as... Figure 6a As shown.

[0122] S140. Determine the target defect measurement value based on the perimeter of the fitted shape of the target monitoring hole with M apertures in the monitoring image.

[0123] For example, this application selects one or more monitoring holes as target monitoring holes from each type of aperture. That is, one or more monitoring holes are selected from the monitoring holes of the first aperture as target monitoring holes of the first aperture, one or more monitoring holes are selected from the monitoring holes of the second aperture as target monitoring holes of the second aperture, one or more monitoring holes are selected from the monitoring holes of the third aperture as target monitoring holes of the third aperture, and so on, and one or more monitoring holes are selected from the monitoring holes of the Mth aperture as target monitoring holes of the Mth aperture.

[0124] In this application, in order to standardize the data, the number of target monitoring holes for each aperture is the same.

[0125] In some examples, step S130 may include the following steps:

[0126] First, from the M types of monitoring holes in the monitoring image, determine the N target monitoring holes corresponding to each type of hole. Here, N is an integer greater than 0.

[0127] For example, N=1. Then, one monitoring hole can be selected from the monitoring holes of the first aperture as the target monitoring hole of the first aperture, one from the monitoring holes of the second aperture as the target monitoring hole of the second aperture, one from the monitoring holes of the third aperture as the target monitoring hole of the third aperture, and so on, until one monitoring hole is selected from the monitoring holes of the Mth aperture as the target monitoring hole of the Mth aperture. For instance, with M=3, the first aperture being 2µm, the second aperture being 4µm, and the third aperture being 8µm, one can select a monitoring hole of the 2µm aperture as the target monitoring hole of the 2µm aperture, one from the 4µm aperture as the target monitoring hole of the 4µm aperture, and one from the 8µm aperture as the target monitoring hole of the 8µm aperture.

[0128] For example, N=2, then two monitoring holes can be selected from the monitoring holes of the first aperture as target monitoring holes of the first aperture, two monitoring holes from the monitoring holes of the second aperture as target monitoring holes of the second aperture, two monitoring holes from the monitoring holes of the third aperture as target monitoring holes of the third aperture, and so on, until two monitoring holes are selected from the monitoring holes of the Mth aperture as target monitoring holes of the Mth aperture. For example, taking M=3, the first aperture is 2µm, the second aperture is 4µm, and the third aperture is 8µm as an example, two monitoring holes of the 2µm aperture can be selected as target monitoring holes of the 2µm aperture, two monitoring holes of the 4µm aperture can be selected as target monitoring holes of the 4µm aperture, and two monitoring holes of the 8µm aperture can be selected as target monitoring holes of the 8µm aperture.

[0129] For example, N=3, then 3 monitoring holes can be selected from the monitoring holes of the first aperture as target monitoring holes of the first aperture, 3 monitoring holes can be selected from the monitoring holes of the second aperture as target monitoring holes of the second aperture, 3 monitoring holes can be selected from the monitoring holes of the third aperture as target monitoring holes of the third aperture, ... and 3 monitoring holes can be selected from the monitoring holes of the Mth aperture as target monitoring holes of the Mth aperture. For example, combined with Figure 6a As shown, taking M=3, with the first aperture being 2µm, the second aperture being 4µm, and the third aperture being 8µm as an example, three monitoring holes can be selected from the monitoring holes with an aperture of 2µm (such as GK). 11 GK 12 GK 13 As the target monitoring hole with an aperture of 2µm, three monitoring holes (such as GK) are selected from the monitoring holes with an aperture of 4µm. 21 GK 22 GK 23 As a target monitoring hole with an aperture of 4µm, from a monitoring hole with an aperture of 8µm (such as GK) 31 GK 32 GK 33 Three monitoring holes were selected as target monitoring holes with a diameter of 8 μm.

[0130] It should be noted that the specific value of M can be determined according to the needs of the actual application environment, and is not limited here.

[0131] For example, the target monitoring holes selected from different apertures can be monitoring holes at the same location in the corresponding area. Alternatively, the target monitoring holes selected from different apertures can also be monitoring holes at different locations in the corresponding area, without limitation.

[0132] Next, the perimeter of the fitted shape for each of the N target monitoring holes with M aperture sizes is calculated. For example, a closed regular shape formed by the outermost vertices of each of the N target monitoring holes with different aperture sizes is fitted. Based on the closed regular shape corresponding to each of the N target monitoring holes with different aperture sizes and the formula for calculating the perimeter of the closed regular shape, the perimeter of the fitted shape for each of the N target monitoring holes with different aperture sizes is determined.

[0133] For example, combined Figure 6a and Figure 7 As shown, for the target monitoring hole GK 11 The target monitoring hole GK 11 For the first target monitoring hole in the first aperture, the outermost vertex of the fitted shape forms a closed regular pattern SK. 11 The closed regular graph SK 11 If it is a circle, then it can be determined according to the closed rule of shape SK. 11 The corresponding formula for calculating the circumference of a circle determines the target monitoring hole GK. 11 The perimeter C of the fitted shape 11 =πd 11 d 11 SK is a closed regular graph 11 The diameter, d 11 It can be obtained through measurement.

[0134] For example, combined Figure 6a and Figure 6b As shown, for the target monitoring hole GK 12 The target monitoring hole GK 12 For the second target monitoring hole in the first aperture, the outermost vertex of the fitted shape forms a closed regular pattern SK. 12 The closed regular graph SK 12 If it is a circle, then it can be determined according to the closed rule of shape SK. 12 The corresponding formula for calculating the circumference of a circle determines the target monitoring hole GK. 12 The perimeter C of the fitted shape 12 =πd 12 d 12 SK is a closed regular graph 12 The diameter, d 12 It can be obtained through measurement.

[0135] For example, combined Figure 6a and Figure 6b As shown, for the target monitoring hole GK 13 The target monitoring hole GK 13For the third target monitoring hole in the first aperture, the outermost vertex of the fitted shape forms a closed regular pattern SK. 13 The closed regular graph SK 13 If it is a circle, then it can be determined according to the closed rule of shape SK. 13 The corresponding formula for calculating the circumference of a circle determines the target monitoring hole GK. 13 The perimeter C of the fitted shape 11 =πd 13 d 13 SK is a closed regular graph 13 The diameter, d 13 It can be obtained through measurement.

[0136] For example, combined Figure 6a and Figure 6b As shown, for the target monitoring hole GK 21 The target monitoring hole GK 21 For the first target monitoring hole in the second aperture monitoring hole, the outermost vertex of the fitted shape forms a closed regular pattern SK. 21 The closed regular graph SK 21 If it is a circle, then it can be determined according to the closed rule of shape SK. 21 The corresponding formula for calculating the circumference of a circle determines the target monitoring hole GK. 21 The perimeter C of the fitted shape 21 =πd 21 d 21 SK is a closed regular graph 21 The diameter, d 21 It can be obtained through measurement.

[0137] For example, combined Figure 6a and Figure 6b As shown, for the target monitoring hole GK 22 The target monitoring hole GK 22 For the second target monitoring hole in the second aperture, the outermost vertex of the fitted shape forms a closed regular pattern SK. 22 The closed regular graph SK 22 If it is a circle, then it can be determined according to the closed rule of shape SK. 22 The corresponding formula for calculating the circumference of a circle determines the target monitoring hole GK. 22 The perimeter C of the fitted shape 22 =πd 22 d 22 SK is a closed regular graph 22 The diameter, d 22 It can be obtained through measurement.

[0138] For example, combined Figure 6a and Figure 6b As shown, for the target monitoring hole GK 23 The target monitoring hole GK 23 For the third target monitoring hole in the second aperture monitoring hole, the outermost vertex of the fitted shape forms a closed regular pattern SK. 23 The closed regular graph SK 23 If it is a circle, then it can be determined according to the closed rule of shape SK. 23 The corresponding formula for calculating the circumference of a circle determines the target monitoring hole GK. 23 The perimeter C of the fitted shape 22 =πd 23 d 23 SK is a closed regular graph 23 The diameter, d 23 It can be obtained through measurement.

[0139] For example, combined Figure 6a and Figure 6b As shown, for the target monitoring hole GK 31 The target monitoring hole GK 31 For the first target monitoring hole in the third aperture monitoring hole, the outermost vertex of the fitted shape forms a closed regular pattern SK. 31 The closed regular graph SK 31 If it is elliptical, then it can be determined according to the closed rule of the figure SK. 31 The corresponding formula for calculating the perimeter of the ellipse is used to determine the target monitoring hole GK. 31 The perimeter C of the fitted shape 31 =2πb 31 +4(a 31 -b 31 ), a 31 SK is a closed regular graph 31 The major axis, b 31 SK is a closed regular graph 31 The minor axis, and a 31 and b 31 It can be obtained through measurement.

[0140] For example, combined Figure 6a and Figure 6b As shown, for the target monitoring hole GK 32 The target monitoring hole GK 32 For the second target monitoring hole in the third aperture monitoring hole, the outermost vertex of the fitted shape forms a closed regular pattern SK. 32 The closed regular graph SK 32 If it is elliptical, then it can be determined according to the closed rule of the figure SK. 32 The corresponding formula for calculating the perimeter of the ellipse is used to determine the target monitoring hole GK. 32 The perimeter C of the fitted shape32 =2πb 32 +4(a 32 -b 32 ), a 32 SK is a closed regular graph 32 The major axis, b 32 SK is a closed regular graph 32 The minor axis, and a 32 and b 32 It can be obtained through measurement.

[0141] For example, combined Figure 6a and Figure 6b As shown, for the target monitoring hole GK 33 The target monitoring hole GK 33 For the third target monitoring hole in the third aperture, the outermost vertex of the fitted shape forms a closed regular pattern SK. 33 The closed regular graph SK 33 If it is elliptical, then it can be determined according to the closed rule of the figure SK. 33 The corresponding formula for calculating the perimeter of the ellipse is used to determine the target monitoring hole GK. 33 The perimeter C of the fitted shape 33 =2πb 33 +4(a 33 -b 33 ), a 33 SK is a closed regular graph 33 The major axis, b 33 SK is a closed regular graph 33 The minor axis, and a 33 and b 33 It can be obtained through measurement.

[0142] It should be noted that closed regular shapes can include at least one of circles and ellipses. Of course, in practical applications, closed regular shapes can also be other shapes, which can be determined according to the needs of the actual application environment, and are not limited here.

[0143] Then, based on the perimeter of the fitted shape of each of the N target monitoring holes with M aperture sizes, the target defect measurement value is determined. For example, the nth initial defect measurement value is determined based on the perimeter of the fitted shape of the nth target monitoring hole among the N target monitoring holes with M aperture sizes; n is an integer and 1 ≤ n ≤ N. Furthermore, the predicted average value from the first initial defect measurement value to the Nth initial defect measurement value is determined, and this predicted average value is used as the target defect measurement value. Optionally, the nth initial defect measurement value is determined based on the difference between the perimeter of the fitted shape of the nth target monitoring hole among the N target monitoring holes with M aperture sizes and the corresponding design perimeter.

[0144] For example, the following formula is used to determine the nth initial defect measurement value based on the difference between the perimeter of the fitted shape of the nth target monitoring hole and the corresponding design perimeter among N target monitoring holes of M apertures.

[0145]

[0146] Among them, S n R represents the nth initial defect measurement value. m C represents the similarity ratio of the shape of the monitoring hole with diameter m to the shape of the monitoring hole with diameter 1. mn C represents the perimeter of the fitted shape of the nth target monitoring hole among the monitoring holes with diameter m. m-design Let m represent the design perimeter of the monitoring hole with the m-th aperture, where m is an integer and 1 ≤ m ≤ M. In actual manufacturing processes, larger apertures exhibit more pronounced defects; for example, as the aperture of the etched hole increases, the overall vertical stripe-like defects on the sidewalls also increase. During defect measurement, the similarity ratio R is used... m The settings can further balance the weights of defect data with different pore sizes, which is beneficial to improving the accuracy of defect measurement.

[0147] For example, the design perimeter of the monitoring hole of the m-th aperture is the perimeter of the monitoring hole calculated based on the aperture determined during the process fabrication design.

[0148] For example, it is possible to make The following formula can be used to determine the nth initial defect measurement value based on the difference between the perimeter of the fitted shape of the nth target monitoring hole and the corresponding design perimeter among the N target monitoring holes of M apertures.

[0149]

[0150] Among them, S n Z represents the nth initial defect measurement value, Z1 represents the diameter of the monitoring hole with the first aperture, Z m C represents the diameter of the monitoring hole with diameter m. mn Z1 represents the perimeter of the fitted shape of the nth target monitoring hole among the monitoring holes with diameter m, where m is an integer and 1 ≤ m ≤ M. In actual processes, the larger the hole diameter, the more obvious the defects become; for example, as the diameter of the etched hole increases, the overall size of the sidewall vertical stripe defects also increases. During defect measurement, Z1 and Z2 are used... m The ratio can further balance the weight of defect data of different pore sizes, which is conducive to improving the accuracy of defect measurement.

[0151] For example, with M=3, the first aperture is 2µm, the second aperture is 4µm, and the third aperture is 8µm, based on the target monitoring aperture GK... 11The perimeter C of the fitted shape 11 =πd 11 Target monitoring hole GK 21 The perimeter C of the fitted shape 21 =πd 21 and the target monitoring hole GK 31 The perimeter C of the fitted shape 31 =2πb 31 +4(a 31 -b 31 ), determine the first initial defect measurement value S1, and,

[0152] Furthermore, according to the target monitoring hole GK 12 The perimeter C of the fitted shape 12 =πd 12 Target monitoring hole GK 22 The perimeter C of the fitted shape 22 =πd 22 and the target monitoring hole GK 32 The perimeter C of the fitted shape 32 =2πb 32 +4(a 32 -b 32 ), determine the second initial defect measurement value S2, and,

[0153] Furthermore, according to the target monitoring hole GK 13 The perimeter C of the fitted shape 13 =πd 13 Target monitoring hole GK 23 The perimeter C of the fitted shape 23 =πd 23 and the target monitoring hole GK 33 The perimeter C of the fitted shape 33 =2πb 33 +4(a 33 -b 33 ), determine the third initial defect measurement value S3, and,

[0154] For example, the predicted average value from the first initial defect measurement to the Nth initial defect measurement is determined using the following formula;

[0155]

[0156] Among them, S n This represents the nth initial defect measurement value. This represents the predicted average.

[0157] For example, taking M=3, with the first aperture being 2µm, the second aperture being 4µm, and the third aperture being 8µm, the predicted average value from the first initial defect measurement S1 to the third initial defect measurement S3 is... And the average of the predictions The target defect measurement value was determined.

[0158] In this embodiment, a monitoring hole is formed by etching the target monitoring sheet, and then the target monitoring sheet is planarized to a set monitoring height. A monitoring image of the side of the target monitoring sheet with the monitoring hole at the set monitoring height is obtained. The perimeter of the fitted shape of the monitoring hole in the monitoring image is used to determine the target defect measurement value. The defect measurement value of the monitoring hole at the set monitoring height can be measured and quantified to achieve vertical stripe defects.

[0159] like Figure 7 As shown, the method for monitoring the etching cavity provided in this embodiment may include steps S110 to S170. Steps S110 to S140 can be referred to the description of the preparation method above, and will not be repeated here.

[0160] S150. Determine whether the measured value of the target defect exceeds the set threshold range. If yes, proceed to step S160; otherwise, proceed to step S170.

[0161] For example, setting the threshold range can be achieved using a detection threshold. This is composed of the detection threshold error σ. For example, the threshold range can be set as follows: That is, the threshold range can be set to Where j is an integer greater than 0. Optionally, if j = 1, then the threshold range can be set to... If j=2, then the threshold range can be set as follows: If j=3, then the threshold range can be set as follows: If j=4, then the threshold range can be set as follows: It should be noted that the specific value of j can be determined according to the needs of the actual application environment, and is not limited here.

[0162] S160. Determine that the etching cavity is in an abnormal working state during the current monitoring cycle.

[0163] For example, a threshold range is set as For example, in the target defect measurement value Exceeding The included numerical range indicates that defects (such as vertical stripe defects) in the etched monitoring holes on the target monitoring chip have an adverse effect on the performance of the subsequently fabricated semiconductor device, and these defects (such as vertical stripe defects) cannot be ignored. This allows for the timely detection of abnormal etching cavities, and consequently, the monitoring of the stability of the etching cavities.

[0164] S170. Confirm that the etching cavity is in normal working condition during the current monitoring cycle.

[0165] For example, a threshold range is set as For example, in the target defect measurement value In The included numerical range indicates that defects (such as vertical stripe defects) in the etched monitoring holes on the target monitoring chip do not adversely affect the performance of the subsequently fabricated semiconductor device, and such defects (such as vertical stripe defects) are negligible. This allows for the timely detection of abnormal etching cavities, and consequently, the monitoring of the stability of the etching cavities.

[0166] The method for measuring defects in etched holes provided in this disclosure involves etching a target monitoring sheet to form a monitoring hole, then planarizing the target monitoring sheet to a set monitoring height. A monitoring image of the side of the target monitoring sheet with the monitoring hole at the set monitoring height is acquired. Based on the perimeter of the fitted shape of the monitoring hole in the monitoring image, the measurement value of the target defect is determined, thus measuring and quantifying the defect value of the monitoring hole at the set monitoring height. By comparing the target defect measurement value with a set threshold range, anomalies can be detected promptly, thereby monitoring the stability of the etching cavity. Furthermore, this disclosure also reduces the influence of hole size on the vertical stripe defects of the monitoring hole by setting multiple monitoring holes with different diameters.

[0167] The method for determining the threshold range is explained below.

[0168] like Figure 8 As shown in the embodiments of this disclosure, a method for determining a set threshold range is provided, including the following steps:

[0169] S210. Obtain the first and second defect measurement values ​​corresponding to the test piece in each of the Y sequentially executed test cycles.

[0170] In some examples, step S210 includes:

[0171] First, a detection patch is formed in the y-th detection period out of Y detection periods. Here, Y is an integer greater than 1.

[0172] For example, an interval time can be set, and each detection cycle can be executed sequentially according to the set interval time. For instance, if Y=2, the work process of the first detection cycle is executed first, and after an interval time, the work process of the second detection cycle is executed. Or, if Y=3, the work process of the first detection cycle is executed first, and after an interval time, the work process of the second detection cycle is executed, and after another interval time, the work process of the third detection cycle is executed. Or, if Y=4, the work process of the first detection cycle is executed first, and after an interval time, the work process of the second detection cycle is executed, and after another interval time, the work process of the third detection cycle is executed, and after another interval time, the work process of the fourth detection cycle is executed.

[0173] It should be noted that the specific value of Y can be determined according to the needs of the actual application environment, and is not limited here.

[0174] It should be noted that the specific value of the interval time is not limited in the embodiments disclosed herein. For example, the interval time can be 24h, 36h, 48h, 72h, etc.

[0175] For example, the detection sheet has multiple detection holes of M different aperture sizes, and the detection holes are filled with a dielectric material. For instance, the detection holes of the M different aperture sizes are divided into detection holes of aperture 1 to aperture M, in ascending order of aperture size. Thus, multiple detection holes of aperture 1, multiple detection holes of aperture 2, multiple detection holes of aperture 3, ..., multiple detection holes of aperture M are etched into the target monitoring sheet. In actual processes, the larger the aperture, the more obvious the defects. This embodiment of the disclosure reduces the influence of aperture size on vertical stripe defects in the detection holes by setting multiple detection holes of different aperture sizes.

[0176] It should be noted that the ideal shape of the detection hole formed by etching in this embodiment is circular. Furthermore, the diameter of the detection hole is the diameter of this ideal shape (i.e., circular). In other words, this diameter refers to the diameter determined during the design phase, not the actual diameter of the fabricated detection hole.

[0177] This disclosure does not limit the specific value of each of the M aperture sizes. For example, taking M=3, the first aperture can be 2µm, the second aperture can be 4µm, and the third aperture can be 8µm.

[0178] In this embodiment of the disclosure, the depth of each detection hole formed by etching in the detection wafer is H. This embodiment of the disclosure does not limit the specific value of H. Exemplarily, H is 40µm to 60µm. For example, H can be 40µm, 50µm, or 60µm.

[0179] It should be noted that due to process factors, the depth of different detection holes may vary slightly. As long as the depth of the detection hole is H within the allowable error range, it is acceptable.

[0180] In some examples, forming a detection patch may include the following steps:

[0181] First, multiple detection holes of M different aperture sizes are etched into the detection wafer. For example, as shown... Figure 9a and Figure 9b As shown, a detection wafer 01 is obtained. No other semiconductor devices or structures are fabricated on the detection wafer 01, and the detection wafer 01 undergoes a certain cleaning process to remove impurities from its surface. The cleaned detection wafer 01 is placed in an etching chamber (e.g., a plasma etching chamber), and three aperture sizes are selected: a first aperture of 2µm, a second aperture of 4µm, and a third aperture of 8µm. Multiple detection holes with a depth of H (2µm), multiple detection holes with a depth of H (4µm), and multiple detection holes with a depth of H (8µm) are formed on the detection wafer 01, respectively. Detection holes of the same aperture size are placed in the same region. For example, the detection holes in region 021 have a diameter of 2µm, the detection holes in region 022 have a diameter of 4µm, and the detection holes in region 023 have a diameter of 8µm.

[0182] Next, a dielectric material is coated onto the detection sheet with the detection holes formed, and an oxide is used to fill each of the plurality of detection holes. For example, as... Figure 10a and Figure 10b As shown, oxide 03 is coated on the side of the entire detection sheet 01 where the detection holes are formed, and the oxide 03 completely fills each detection hole with a 2 μm diameter, the oxide completely fills each detection hole with a 4 μm diameter, and the oxide completely fills each detection hole with an 8 μm diameter.

[0183] Alternatively, the oxide may include, but is not limited to, silicon oxide.

[0184] Next, the detection strip is flattened to the first preset detection height. For example, as shown... Figure 11As shown, the oxide-coated detection piece 01 is planarized using a polishing process, which stops when the planarization reaches the first detection set height CS1. This disclosure does not limit the polishing process. Exemplarily, the polishing process used in this embodiment can be Chemical Mechanical Polishing (CMP). Furthermore, this disclosure does not limit the first detection set height. The first detection set height can be the middle of the detection hole. Exemplarily, the range of the first detection set height in this embodiment can be 0.45H to 0.55H. For example, the first detection set height can be 0.45H, 0.5H, or 0.55H. When the monitored defect is a sidewall vertical stripe defect, since the sidewall vertical stripe defect is more obvious in the upper part of the hole, and the morphology of the upper part of the hole deteriorates with the increase of the etching cavity's usage time, the sidewall vertical stripe defect in the upper part of the hole will also increase. However, the sidewall vertical stripe defect in the middle of the hole does not change significantly with the increase of the etching cavity's usage time. Therefore, when the first detection setting height is set in the middle of the hole, the determined detection threshold and the detection threshold error are not easily affected by the usage time of the etching cavity.

[0185] Next, a first detection image is obtained on the side of the detection patch with the detection hole at the first detection set height. For example, the detection patch, flattened to the first detection set height, can be placed in a CD SEM, and the first detection image of the side of the detection patch with the detection hole can be obtained using the CD SEM, such as... Figure 12a As shown.

[0186] Then, based on the perimeter of the fitted shape of the selected detection holes of the M aperture sizes in the first detection image, the first detection defect measurement value corresponding to the y-th detection cycle is determined. For example, K first target detection holes corresponding to each aperture size can be determined from the detection holes of the M aperture sizes in the first detection image; where K is an integer greater than 0. Furthermore, the perimeter of the fitted shape of each of the K first target detection holes of the M aperture sizes is calculated, and the first detection defect measurement value corresponding to the y-th detection cycle is determined based on the perimeter of the fitted shape of each of the K first target detection holes of the M aperture sizes.

[0187] For example, this application selects one or more detection holes from each type of aperture as the first target detection hole. That is, one or more detection holes are selected from the detection holes of the first aperture as the first target detection hole of the first aperture, one or more detection holes are selected from the detection holes of the second aperture as the first target detection hole of the second aperture, one or more detection holes are selected from the detection holes of the third aperture as the first target detection hole of the third aperture, and so on, up to one or more detection holes are selected from the detection holes of the Mth aperture as the first target detection hole of the Mth aperture. Furthermore, to ensure data consistency, the number of first target detection holes is the same for each aperture.

[0188] Optionally, K can be set to 3. Then, three detection holes can be selected from the detection holes of the first aperture as the first target detection holes of the first aperture, three detection holes can be selected from the detection holes of the second aperture as the first target detection holes of the second aperture, three detection holes can be selected from the detection holes of the third aperture as the first target detection holes of the third aperture, and so on, until three detection holes are selected from the detection holes of the Mth aperture as the first target detection holes of the Mth aperture. For example, combined with... Figure 12a As shown, taking M=3, y=1 as an example, with the first aperture being 2µm, the second aperture being 4µm, and the third aperture being 8µm, three detection wells (such as RA) can be selected from the detection wells with an aperture of 2µm. 111 RA 121 RA 131 As the first target detection well with a pore size of 2µm, three detection wells (such as RA) are selected from the detection wells with a pore size of 4µm. 211 RA 221 RA 231 As the first target detection well with a pore size of 4µm, from the detection well with a pore size of 8µm (such as RA) 311 RA 321 RA 331 Three detection wells were selected as the first target detection wells with a diameter of 8 μm.

[0189] It should be noted that the specific value of M can be determined according to the needs of the actual application environment, and is not limited here.

[0190] For example, to calculate the perimeter of the fitted shape of each first target detection hole, a closed regular shape formed by the outermost vertices of each of the K first target detection holes with different apertures can be fitted. Based on the closed regular shape corresponding to each of the K first target detection holes with different apertures and the perimeter calculation formula corresponding to the closed regular shape, the perimeter of each of the K first target detection holes with different apertures is determined.

[0191] Optionally, taking K=3 as an example, combined with Figure 12a and Figure 12b As shown, for the first target detection hole RA 111 The first target detection hole RA 111 For the first target detection hole of the first aperture in the first detection cycle, the outermost vertex of the hole is fitted to form a closed regular pattern QA. 111 The closed-loop regular graph QA 111 If it is a circle, then it can be determined according to the closed-loop rule of the figure QA. 111 The corresponding formula for calculating the circumference of a circle determines the first detection hole RA for the first target. 111 The perimeter CA of the fitted shape 111 =πdA 111 dA 111 QA for closed regular graphs 111 The diameter, dA 111 It can be obtained through measurement.

[0192] Optionally, combined Figure 12a and Figure 12b As shown, for the first target detection hole RA 121 The first target detection hole RA 121 For the second first target detection hole in the first aperture of the first detection cycle, the outermost vertex of the fitted shape forms a closed regular pattern QA. 121 The closed rule graph QA 121 If it is a circle, then it can be determined according to the closed-loop rule of the figure QA. 121 The corresponding formula for calculating the circumference of a circle determines the second detection hole RA for the first target. 121 The perimeter CA of the fitted shape 121 =πdA 121 dA 121 QA for closed regular graphs 121 The diameter, dA 121 It can be obtained through measurement.

[0193] Optionally, combined Figure 12a and Figure 12b As shown, for the first target detection hole RA 131 The first target detection hole RA 131 For the third first target detection hole in the first aperture of the first detection cycle, the outermost vertex of the fitted shape forms a closed regular pattern QA. 131 The closed-loop regular graph QA 131 If it is a circle, then it can be determined according to the closed rule of shape QA. 131 The corresponding formula for calculating the circumference of a circle determines the third detection hole RA for the first target. 131 The perimeter CA of the fitted shape 131=πdA 131 dA 131 QA for closed regular graphs 131 The diameter, dA 131 It can be obtained through measurement.

[0194] Optionally, combined Figure 12a and Figure 12b As shown, for the first target detection hole RA 211 The first target detection hole RA 211 For the first target detection hole in the second aperture of the first detection cycle, the outermost vertex of the hole is fitted to form a closed regular pattern QA. 211 The closed-loop regular graph QA 211 If it is a circle, then it can be determined according to the closed rule of shape QA. 211 The corresponding formula for calculating the circumference of a circle determines the first detection hole RA for the first target. 211 The perimeter CA of the fitted shape 211 =πdA 211 dA 211 QA for closed regular graphs 211 The diameter, dA 211 It can be obtained through measurement.

[0195] Optionally, combined Figure 12a and Figure 12b As shown, for the first target detection hole RA 221 The first target detection hole RA 221 For the second first target detection hole in the second aperture of the first detection cycle, the outermost vertex of the hole is fitted to form a closed regular pattern QA. 221 The closed-loop regular graph QA 221 If it is a circle, then it can be determined according to the closed rule of shape QA. 221 The corresponding formula for calculating the circumference of a circle determines the second detection hole RA for the first target. 221 The perimeter CA of the fitted shape 221 =πdA 221 dA 221 QA for closed regular graphs 221 The diameter, dA 221 It can be obtained through measurement.

[0196] Optionally, combined Figure 12a and Figure 12b As shown, for the first target detection hole RA 231 The first target detection hole RA 231 For the third first target detection hole in the second aperture detection hole in the first detection cycle, the outermost vertex of the fitted shape forms a closed regular pattern QA.231 The closed-loop regular graph QA 231 If it is a circle, then it can be determined according to the closed rule of shape QA. 231 The corresponding formula for calculating the circumference of a circle determines the third detection hole RA for the first target. 231 The perimeter CA of the fitted shape 231 =πdA 231 dA 231 QA for closed regular graphs 231 The diameter, dA 231 It can be obtained through measurement.

[0197] Optionally, combined Figure 12a and Figure 12b As shown, for the first target detection hole RA 311 The first target detection hole RA 311 For the first target detection hole in the third aperture of the first detection cycle, the outermost vertex of the hole is fitted to form a closed regular pattern QA. 311 The closed-loop regular graph QA 311 If it is a circle, then it can be determined according to the closed rule of shape QA. 311 The corresponding formula for calculating the circumference of a circle determines the first detection hole RA for the first target. 311 The perimeter CA of the fitted shape 311 =πdA 311 dA 311 QA for closed regular graphs 311 The diameter, dA 311 It can be obtained through measurement.

[0198] Optionally, combined Figure 12a and Figure 12b As shown, for the first target detection hole RA 321 The first target detection hole RA 321 For the second first target detection hole in the third aperture detection hole in the first detection cycle, the outermost vertex of the fitted shape forms a closed regular pattern QA. 321 The closed-loop regular graph QA 321 If it is a circle, then it can be determined according to the closed rule of shape QA. 321 The corresponding formula for calculating the circumference of a circle determines the second detection hole RA for the first target. 321 The perimeter CA of the fitted shape 321 =πdA 321 dA 321 QA for closed regular graphs 321 The diameter, dA 321 It can be obtained through measurement.

[0199] Optionally, combined Figure 12a and Figure 12b As shown, for the first target detection hole RA 331 The first target detection hole RA 331 For the third first target detection hole in the third aperture of the first detection cycle, the outermost vertex of the hole is fitted to form a closed regular pattern QA. 331 The closed-loop regular graph QA 331 If it is a circle, then it can be determined according to the closed rule of shape QA. 331 The corresponding formula for calculating the circumference of a circle determines the third detection hole RA for the first target. 331 The perimeter CA of the fitted shape 331 =πdA 331 dA 331 QA for closed regular graphs 331 The diameter, dA 331 It can be obtained through measurement.

[0200] Similarly, when Y=4, and y=2, y=3, and y=4, we can obtain the perimeter of the fitted shape corresponding to the first to third first target detection holes in the detection holes of the first to third apertures in the second detection cycle, the perimeter of the fitted shape corresponding to the first to third first target detection holes in the detection holes of the first to third apertures in the third detection cycle, and the perimeter of the fitted shape corresponding to the first to third first target detection holes in the detection holes of the first to third apertures in the fourth detection cycle. For details, please refer to the above description; further details will not be elaborated here.

[0201] It should be noted that closed regular shapes can include at least one of circles and ellipses. Of course, in practical applications, closed regular shapes can also be other shapes, which can be determined according to the needs of the actual application environment, and are not limited here.

[0202] For example, determining the first detection defect measurement value corresponding to the y-th detection cycle based on the perimeter of the fitted shape of each of the K first target detection holes of M aperture sizes can include: First, determining the k-th first initial detection defect measurement value corresponding to the y-th detection cycle based on the perimeter of the fitted shape of the k-th first target detection hole of the K first target detection holes of M aperture sizes; k is an integer and 1≤k≤K. Then, determining the first detection prediction average value from the 1st to the Kth first initial detection defect measurement value in the y-th detection cycle, and determining the first detection prediction average value as the first detection defect measurement value corresponding to the y-th detection cycle.

[0203] Optionally, the following formula is used to determine the measurement value of the first initial detection defect corresponding to the yth detection cycle based on the perimeter of the fitted shape of the kth first target detection hole among the K first target detection holes of M apertures;

[0204]

[0205] Among them, SA ky Z represents the measurement value of the first initial defect in the y-th detection cycle, Z1 represents the diameter of the detection hole with the first aperture, Z m CA represents the diameter of the detection hole with diameter m. mky Let m represent the perimeter of the fitted shape of the k-th first target detection hole in the m-th aperture of the detection hole in the y-th detection cycle, where m is an integer and 1≤m≤M.

[0206] And, using the following formula, the first detection prediction average value from the first initial detection defect measurement value to the Kth initial detection defect measurement value in the y-th detection cycle is determined;

[0207]

[0208] in, This represents the average value of the first detection prediction.

[0209] For example, taking y=1 and K=3 as an example, the first target detection hole RA of the first aperture in the first detection cycle can be used as a reference. 111 The perimeter CA of the fitted shape 111 The first target detection aperture RA of the second aperture 211 The perimeter CA of the fitted shape 211 The first target detection aperture RA of the third aperture 311 The perimeter CA of the fitted shape 311 The first initial defect measurement value SA corresponding to the first detection cycle is obtained. 11 .and,

[0210] Furthermore, the second first target detection hole RA of the first aperture in the first detection cycle can be used as a reference. 121 The perimeter CA of the fitted shape 121 The second first target detection aperture RA of the second aperture 221 The perimeter CA of the fitted shape 221 The second first target detection aperture RA of the third aperture 321 The perimeter CA of the fitted shape 321 The second initial defect measurement value SA corresponding to the first detection cycle is obtained. 21 .and,

[0211] Furthermore, the third first target detection hole RA of the first aperture in the first detection cycle can be used as a reference. 131 The perimeter CA of the fitted shape 131 The third first target detection aperture RA of the second aperture 231 The perimeter CA of the fitted shape 231 The third aperture of the third first target detection aperture RA 331 The perimeter CA of the fitted shape 331 The third initial defect measurement value SA corresponding to the first detection cycle is obtained. 31 .and,

[0212] And, determine the first initial defect measurement value SA in the first inspection cycle. 11 Up to the third initial defect measurement value SA 31 First detection prediction average and,

[0213] Similarly, the average value of the first detection prediction in the second detection period and the average value of the first detection prediction in the third detection cycle This can be deduced in the same way, and will not be elaborated upon here.

[0214] Next, the detection piece, which has been flattened to the first detection set height, undergoes further flattening processing to reach the second detection set height. For example, as shown... Figure 13As shown, the detection piece 01 is further planarized through a polishing process, stopping when the planarization reaches the second detection set height CS2. This disclosure does not limit the polishing process. Exemplarily, the polishing process used in this embodiment can be Chemical Mechanical Polishing (CMP). Furthermore, this disclosure does not limit the second detection set height. The second detection set height can be the lower part of the detection hole. Exemplarily, the range of the second detection set height in this embodiment can be 0.2H to 0.3H. For example, the first detection set height can be 0.2H, 0.25H, or 0.3H. When the monitored defect is a sidewall vertical stripe defect, since the sidewall vertical stripe defect is more obvious in the upper part of the hole, and the morphology of the upper part of the hole deteriorates with the increase of the etching cavity's usage time, the sidewall vertical stripe defect in the upper part of the hole will increase accordingly. However, the sidewall vertical stripe defect situation in the lower part of the hole does not change significantly with the increase of the etching cavity's usage time. Therefore, when the second detection setting height is set at the bottom of the hole, the determined detection threshold and the detection threshold error are less likely to be affected by the usage time of the etching cavity.

[0215] Next, a second detection image is acquired on the side of the target monitoring piece with the detection hole at the second detection set height. For example, the detection piece flattened to the second detection set height can be placed in a CD SEM, and a second detection image of the side of the detection piece with the detection hole can be acquired using the CD SEM, such as... Figure 14a As shown. Then, based on the perimeter of the fitted shape of the selected detection holes of the M aperture sizes in the second detection image, the second detection defect measurement value corresponding to the y-th detection cycle is determined. For example, K second target detection holes can be determined from the detection holes of the M aperture sizes in the second detection image; where K is an integer greater than 0. The perimeter of the fitted shape of each of the K second target detection holes of the M aperture sizes is calculated. Based on the perimeter of the fitted shape of each of the K second target detection holes of the M aperture sizes, the second detection defect measurement value corresponding to the y-th detection cycle is determined.

[0216] For example, this application selects one or more detection holes from each aperture size as second target detection holes. That is, one or more detection holes are selected from the detection holes of the first aperture size as second target detection holes of the first aperture size, one or more detection holes are selected from the detection holes of the second aperture size as second target detection holes of the second aperture size, one or more detection holes are selected from the detection holes of the third aperture size as second target detection holes of the third aperture size, and so on, up to one or more detection holes are selected from the detection holes of the Mth aperture size as second target detection holes of the Mth aperture size. Furthermore, to ensure data consistency, the number of second target detection holes is the same for each aperture size.

[0217] Optionally, K can be set to 3. Then, three detection holes can be selected from the detection holes of the first aperture as the second target detection holes of the first aperture, three detection holes from the detection holes of the second aperture as the second target detection holes of the second aperture, three detection holes from the detection holes of the third aperture as the second target detection holes of the third aperture, and so on, until three detection holes are selected from the detection holes of the Mth aperture as the second target detection holes of the Mth aperture. For example, combining... Figure 14a As shown, taking M=3, y=1 as an example, with the first aperture being 2µm, the second aperture being 4µm, and the third aperture being 8µm, three detection wells (such as RB) can be selected from the detection wells with an aperture of 2µm. 111 RB 121 RB 131 As the second target detection well with an aperture of 2µm, three detection wells (such as RB) are selected from the detection wells with an aperture of 4µm. 211 RB 221 RB 231 As a second target detection well with an aperture of 4µm, from a detection well with an aperture of 8µm (such as RB) 311 RB 321 RB 331 Three detection wells were selected as the second target detection wells with an aperture of 8 μm.

[0218] It should be noted that the specific value of M can be determined according to the needs of the actual application environment, and is not limited here.

[0219] For example, to calculate the perimeter of the fitted shape of each second target detection hole, a closed regular shape formed by the outermost vertices of each of the K second target detection holes with different apertures can be fitted. Based on the closed regular shape corresponding to each of the K second target detection holes with different apertures and the perimeter calculation formula corresponding to the closed regular shape, the perimeter of the fitted shape of each of the K second target detection holes with different apertures is determined.

[0220] Optionally, taking K=3 as an example, combined with Figure 14a and Figure 14b As shown, for the second target detection hole RB 111 The second target detection hole RB 111 For the first second target detection hole in the first aperture of the first detection cycle, the outermost vertex of the fitted hole forms a closed regular pattern QB. 111 The closed regular graph QB 111 If it is a circle, then it can be determined according to the closed rule of figure QB. 111 The corresponding formula for calculating the circumference of a circle determines the first detection hole RB for the second target. 111 The perimeter CB of the fitted shape 111 =πdB 111 dB 111 For closed regular graphs QB 111 The diameter, that diameter dB 111 It can be obtained through measurement.

[0221] Optionally, combined Figure 14a and Figure 14b As shown, for the second target detection hole RB 121 The second target detection hole RB 121 For the second target detection hole in the first aperture of the first detection cycle, the outermost vertex of the hole is fitted to form a closed regular pattern QB. 121 The closed regular graph QB 121 If it is a circle, then it can be determined according to the closed rule of figure QB. 121 The corresponding formula for calculating the circumference of a circle determines the second detection hole RB for the second target. 121 The perimeter CB of the fitted shape 121 =πdB 121 dB 121 For closed regular graphs QB 121 The diameter, that diameter dB 121 It can be obtained through measurement.

[0222] Optionally, combined Figure 14a and Figure 14b As shown, for the second target detection hole RB 131 The second target detection hole RB 131 For the third second target detection hole in the first aperture of the first detection cycle, the outermost vertex of the hole is fitted to form a closed regular pattern QB. 131 The closed regular graph QB 131 If it is a circle, then it can be determined according to the closed rule of figure QB. 131 The corresponding formula for calculating the circumference of a circle determines the third detection hole RB for the second target. 131 The perimeter CB of the fitted shape 131=πdB 131 dB 131 For closed regular graphs QB 131 The diameter, that diameter dB 131 It can be obtained through measurement.

[0223] Optionally, combined Figure 14a and Figure 14b As shown, for the second target detection hole RB 211 The second target detection hole RB 211 For the first second target detection hole in the second aperture detection hole in the first detection cycle, the outermost vertex of its fitting forms a closed regular pattern QB. 211 The closed regular graph QB 211 If it is a circle, then it can be determined according to the closed rule of figure QB. 211 The corresponding formula for calculating the circumference of a circle determines the first detection hole RB for the second target. 211 The perimeter CB of the fitted shape 211 =πdB 211 dB 211 For closed regular graphs QB 211 The diameter, that diameter dB 211 It can be obtained through measurement.

[0224] Optionally, combined Figure 14a and Figure 14b As shown, for the second target detection hole RB 221 The second target detection hole RB 221 For the second target detection hole in the second aperture of the first detection cycle, the outermost vertex of the hole is fitted to form a closed regular pattern QB. 221 The closed regular graph QB 221 If it is a circle, then it can be determined according to the closed rule of figure QB. 221 The corresponding formula for calculating the circumference of a circle determines the second detection hole RB for the second target. 221 The perimeter CB of the fitted shape 221 =πdB 221 dB 221 For closed regular graphs QB 221 The diameter, that diameter dB 221 It can be obtained through measurement.

[0225] Optionally, combined Figure 14a and Figure 14b As shown, for the second target detection hole RB 231 The second target detection hole RB 231 For the third second target detection hole in the second aperture detection hole in the first detection cycle, the outermost vertex of the fitted hole forms a closed regular pattern QB.231 The closed regular graph QB 231 If it is a circle, then it can be determined according to the closed rule of figure QB. 231 The corresponding formula for calculating the circumference of a circle determines the third detection hole RB for the second target. 231 The perimeter CB of the fitted shape 231 =πdB 231 dB 231 For closed regular graphs QB 231 The diameter, that diameter dB 231 It can be obtained through measurement.

[0226] Optionally, combined Figure 14a and Figure 14b As shown, for the second target detection hole RB 311 The second target detection hole RB 311 For the first second target detection hole in the third aperture detection hole in the first detection cycle, the outermost vertex of the fitted hole forms a closed regular pattern QB. 311 The closed regular graph QB 311 If it is a circle, then it can be determined according to the closed rule of figure QB. 311 The corresponding formula for calculating the circumference of a circle determines the first detection hole RB for the second target. 311 The perimeter CB of the fitted shape 311 =πdB 311 dB 311 For closed regular graphs QB 311 The diameter, that diameter dB 311 It can be obtained through measurement.

[0227] Optionally, combined Figure 14a and Figure 14b As shown, for the second target detection hole RB 321 The second target detection hole RB 321 For the second target detection hole in the third aperture of the first detection cycle, the outermost vertex of the hole is fitted to form a closed regular pattern QB. 321 The closed regular graph QB 321 If it is a circle, then it can be determined according to the closed rule of figure QB. 321 The corresponding formula for calculating the circumference of a circle determines the second detection hole RB for the second target. 321 The perimeter CB of the fitted shape 321 =πdB 321 dB 321 For closed regular graphs QB 321 The diameter, that diameter dB 321 It can be obtained through measurement.

[0228] Optionally, combined Figure 14a and Figure 14b As shown, for the second target detection hole RB 331 The second target detection hole RB 331 For the third second target detection hole in the third aperture of the first detection cycle, the outermost vertex of the hole is fitted to form a closed regular pattern QB. 331 The closed regular graph QB 331 If it is a circle, then it can be determined according to the closed rule of figure QB. 331 The corresponding formula for calculating the circumference of a circle determines the third detection hole RB for the second target. 331 The perimeter CB of the fitted shape 331 =πdB 331 dB 331 For closed regular graphs QB 331 The diameter, that diameter dB 331 It can be obtained through measurement.

[0229] Similarly, when Y=4, and y=2, y=3, and y=4, we can obtain the perimeter of the fitted shape corresponding to the first to third second target detection holes in the detection holes of the first to third apertures in the second detection cycle, the perimeter of the fitted shape corresponding to the first to third second target detection holes in the detection holes of the first to third apertures in the third detection cycle, and the perimeter of the fitted shape corresponding to the first to third second target detection holes in the detection holes of the first to third apertures in the fourth detection cycle. For details, please refer to the above description; further elaboration will not be repeated here.

[0230] It should be noted that closed regular shapes can include at least one of circles and ellipses. Of course, in practical applications, closed regular shapes can also be other shapes, which can be determined according to the needs of the actual application environment, and are not limited here.

[0231] For example, determining the second detection defect measurement value corresponding to the y-th detection cycle based on the perimeter of the fitted shape of each of the K second target detection holes of M aperture sizes can include: First, determining the k-th second initial detection defect measurement value corresponding to the y-th detection cycle based on the perimeter of the fitted shape of the k-th second target detection hole of the K second target detection holes of M aperture sizes; k is an integer and 1≤k≤K. Then, determining the first detection prediction average value from the 1st second initial detection defect measurement value to the Kth second initial detection defect measurement value in the y-th detection cycle, and determining the first detection prediction average value as the second detection defect measurement value corresponding to the y-th detection cycle.

[0232] Optionally, the following formula is used to determine the kth second initial detection defect measurement value corresponding to the yth detection cycle based on the perimeter of the fitted shape of the kth second target detection hole among the K second target detection holes of the M apertures;

[0233]

[0234] Among them, SB ky Z represents the k-th second initial defect measurement value in the y-th detection cycle, Z1 represents the aperture of the first aperture detection hole, Z m CB represents the diameter of the detection hole with diameter m. mky The perimeter of the fitted shape of the kth second target detection hole in the m-th aperture detection hole during the y-th detection cycle is represented, where m is an integer and 1≤m≤M;

[0235] The second detection prediction average value from the first second initial detection defect measurement value to the Kth second initial detection defect measurement value in the y-th detection cycle is determined using the following formula;

[0236]

[0237] in, This represents the average value of the second detection prediction.

[0238] For example, taking y=1 and K=3 as an example, the first second target detection hole RB of the first aperture in the first detection cycle can be used as a reference. 111 The perimeter CB of the fitted shape 111 The first second target detection aperture RB of the second aperture 211 The perimeter CB of the fitted shape 211 The first second target detection aperture RB of the third aperture 311 The perimeter CB of the fitted shape 311 The first initial defect measurement value SB corresponding to the first detection cycle is obtained. 11 .and,

[0239] Furthermore, the second target detection hole RB of the first aperture in the first detection cycle can be used as a reference. 121 The perimeter CB of the fitted shape 121 The second target detection aperture RB of the second aperture 221 The perimeter CB of the fitted shape 221 The second target detection aperture RB of the third aperture 321 The perimeter CB of the fitted shape 321 The second initial defect measurement value SB corresponding to the first detection cycle is obtained. 21.and,

[0240] Furthermore, the third second target detection hole RB of the first aperture in the first detection cycle can be used as a reference. 131 The perimeter CB of the fitted shape 131 The third second target detection aperture RB of the second aperture 231 The perimeter CB of the fitted shape 231 The third second target detection aperture RB of the third aperture 331 The perimeter CB of the fitted shape 331 The third initial defect measurement value SB corresponding to the first detection cycle is obtained. 31 .and,

[0241] And, determine the first second initial defect measurement value SB in the first inspection cycle. 11 Up to the third second initial defect measurement value SB 31 First detection prediction average and,

[0242] Similarly, the average value of the first detection prediction in the second detection period and the average value of the first detection prediction in the third detection cycle This can be deduced in the same way, and will not be elaborated upon here.

[0243] S220. Determine the detection threshold and detection threshold error based on the first and second detection defect measurement values ​​in Y detection cycles.

[0244] In some examples, the following formula can be used to determine the detection threshold and the detection threshold error based on the first and second detection defect measurements in Y detection cycles;

[0245]

[0246]

[0247]

[0248]

[0249] in, This represents the average value of the first detection prediction in the y-th detection period out of Y detection periods. This represents the average value of the second detection prediction in the y-th detection period out of Y detection periods. σ represents the detection threshold, and σ represents the detection threshold error.

[0250] For example, taking Y=3 as an example, the average value of the first detection prediction in the first detection period can be used. The second detection prediction average value of the first detection cycle The first detection prediction average value of the second detection cycle The second detection prediction average value of the second detection cycle The first prediction average value of the third detection cycle The second detection prediction average value in the third detection cycle Determine the detection threshold and,

[0251] And, based on the first detection prediction average value of the first detection cycle. The second detection prediction average value of the first detection cycle The first detection prediction average value of the second detection cycle The second detection prediction average value of the second detection cycle The first prediction average value of the third detection cycle The second detection prediction average value in the third detection cycle Determine the detection threshold error σ. And,

[0252] S230. Determine the set threshold range based on the detection threshold and the detection threshold error.

[0253] For example, setting the threshold range can be achieved using a detection threshold. This is composed of the detection threshold error σ. For example, the threshold range can be set as follows: That is, the threshold range can be set to Where j is an integer greater than 0. Optionally, if j = 1, then the threshold range can be set to... If j=2, then the threshold range can be set as follows: If j=3, then the threshold range can be set as follows: If j=4, then the threshold range can be set as follows: It should be noted that the specific value of j can be determined according to the needs of the actual application environment, and is not limited here.

[0254] When the monitored defect is a vertical stripe-like defect on the sidewall, this defect is more pronounced at the top of the hole. Furthermore, as the etching chamber's usage time increases, the morphology at the top of the hole deteriorates, leading to an increase in the number of vertical stripe-like defects on the sidewalls at the top. However, the condition of vertical stripe-like defects in the middle and lower parts of the hole does not change significantly with the usage time of the etching chamber. Therefore, when the first and second detection setting heights are set at the middle and lower parts of the hole, respectively, the determined detection threshold and its error are less affected by the usage time of the etching chamber.

[0255] This disclosure also provides a defect measurement device for etched holes, including: a planarization processing device, an image acquisition device, and a defect measurement device. The planarization processing device is configured to acquire a target monitoring sheet and planarize it to a set monitoring height. The target monitoring sheet has multiple monitoring holes of M different apertures, which are formed by etching, where M is an integer greater than 0. The monitoring holes are divided into upper, middle, and lower sections according to their depth from shallow to deep, and the set monitoring height is located at the upper part of the monitoring holes.

[0256] The image acquisition device is configured to acquire a monitoring image of the side of a target monitoring screen with a monitoring hole at a set monitoring height.

[0257] The defect measurement device is configured to determine the target defect measurement value based on the perimeter of the fitted shape of monitoring holes of M different apertures in the monitoring image.

[0258] It should be noted that the working principle and specific implementation of the etching-formed hole defect measurement device are the same as the principle and implementation of the etching-formed hole defect measurement method in the above embodiments. Therefore, the working method of the etching-formed hole defect measurement device can be implemented by referring to the specific implementation of the etching-formed hole defect measurement method in the above embodiments, and will not be repeated here.

[0259] This disclosure also provides a monitoring device for an etching cavity, including: a planarization processing device, an image acquisition device, a defect measurement device, and a data processing device. The planarization processing device is configured to acquire a target monitoring sheet and planarize it to a set monitoring height. The target monitoring sheet has multiple monitoring holes of M different apertures, which are formed by etching, where M is an integer greater than 0. The monitoring holes are divided into upper, middle, and lower sections according to their depth, from shallow to deep, and the set monitoring height is located at the upper part of the monitoring holes.

[0260] The image acquisition device is configured to acquire a monitoring image of the side of a target monitoring screen with a monitoring hole at a set monitoring height.

[0261] The defect measurement device is configured to determine the target defect measurement value based on the perimeter of the fitted shape of monitoring holes of M different apertures in the monitoring image. The data processing device is configured to determine whether the target defect measurement value exceeds a set threshold range; if so, it determines that the etching chamber is in an abnormal operating state in the current monitoring cycle; if not, it determines that the etching chamber is in a normal operating state in the current monitoring cycle.

[0262] For example, the planarization processing apparatus may include a CMP apparatus.

[0263] For example, the image acquisition device may include a CD SEM.

[0264] For example, the data processing device may be implemented using a combination of software and hardware.

[0265] It should be noted that the working principle and specific implementation method of the etching cavity monitoring device are the same as those of the etching cavity monitoring method in the above embodiments. Therefore, the working method of the etching cavity monitoring device can be implemented by referring to the specific implementation method of the etching cavity monitoring method in the above embodiments, and will not be repeated here.

[0266] Those skilled in the art will understand that embodiments of this disclosure can be provided as methods, systems, or computer program products. Therefore, this disclosure can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this disclosure can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0267] This disclosure is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this disclosure. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create a machine for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0268] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0269] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0270] Although preferred embodiments of this disclosure have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this disclosure.

[0271] Obviously, those skilled in the art can make various modifications and variations to the embodiments of this disclosure without departing from the spirit and scope of the embodiments of this disclosure. Therefore, if these modifications and variations to the embodiments of this disclosure fall within the scope of the claims of this disclosure and their equivalents, this disclosure is also intended to include these modifications and variations.

Claims

1. A method for measuring defects in etched holes, characterized in that, include: Obtain a target monitoring sheet, which has multiple monitoring holes of M different apertures. The monitoring holes are formed by etching, where M is an integer greater than 0. The monitoring holes are divided into upper, middle, and lower parts according to their depth from shallow to deep. The target monitoring panel is flattened to a set monitoring height, which is located above the monitoring hole. Acquire a monitoring image of the target monitoring panel at the set monitoring height, on the side with the monitoring hole; The target defect measurement value is determined based on the perimeter of the fitted shape of the monitoring hole with the M aperture sizes in the monitoring image.

2. The method for measuring defects in etched holes as described in claim 1, characterized in that, Before flattening the target monitoring image to the set monitoring height, the method further includes: The monitoring hole is filled with a medium material, which is different from the material of the target monitoring sheet.

3. The method for measuring defects in etched holes as described in claim 1 or 2, characterized in that, The step of determining the target defect measurement value based on the perimeter of the fitted shape of the target monitoring hole with the M aperture sizes in the monitoring image includes: From the M aperture sizes in the monitoring image, determine N target monitoring holes corresponding to each aperture size; where N is an integer greater than 0. Calculate the perimeter of the fitted shape for each of the N target monitoring holes of the M aperture sizes; The target defect measurement value is determined based on the perimeter of the fitted shape of each of the N target monitoring holes of the M apertures.

4. The method for measuring defects in etched holes as described in claim 3, characterized in that, The step of determining the target defect measurement value based on the perimeter of the fitted shape of each of the N target monitoring holes of the M aperture types includes: Based on the perimeter of the fitted shape of the nth target monitoring hole among the N target monitoring holes of the M apertures, the nth initial defect measurement value is determined; n is an integer and 1≤n≤N; Determine the predicted average value from the first initial defect measurement value to the Nth initial defect measurement value, and determine the predicted average value as the target defect measurement value.

5. The method for measuring defects in etched holes as described in claim 4, characterized in that, The step of determining the nth initial defect measurement value based on the perimeter of the fitted shape of the nth target monitoring hole among the N target monitoring holes of the M aperture sizes includes: The nth initial defect measurement value is determined based on the difference between the perimeter of the fitted shape of the nth target monitoring hole and the corresponding design perimeter among the N target monitoring holes of the M apertures.

6. The method for measuring defects in etched holes as described in claim 5, characterized in that, According to the order of the aperture size from small to large, the M aperture sizes are divided into apertures of size 1 to aperture size M. The following formula is used to determine the nth initial defect measurement value based on the difference between the perimeter of the fitted shape of the nth target monitoring hole and the corresponding design perimeter among the N target monitoring holes of the M apertures. ； Among them, S n R represents the nth initial defect measurement value. m C represents the similarity ratio of the shape of the monitoring hole with diameter m to the shape of the monitoring hole with diameter 1. mn C represents the perimeter of the fitted shape of the nth target monitoring hole among the monitoring holes of the mth aperture. m-design Let m represent the design perimeter of the monitoring hole with the m-th aperture, where m is an integer and 1 ≤ m ≤ M.

7. The method for measuring defects in etched holes as described in claim 6, characterized in that, ， ； The following formula is used to determine the nth initial defect measurement value based on the difference between the perimeter of the fitted shape of the nth target monitoring hole and the corresponding design perimeter among the N target monitoring holes of the M apertures. ； Among them, S n Z represents the nth initial defect measurement value, Z1 represents the diameter of the monitoring hole of the first aperture, Z m C represents the diameter of the monitoring hole with diameter m. mn The perimeter represents the fitted shape of the nth target monitoring hole among the monitoring holes of the mth aperture.

8. The method for measuring defects in etched holes as described in claim 6 or 7, characterized in that, The predicted average value from the first initial defect measurement to the Nth initial defect measurement value is determined using the following formula; ； Among them, S n This represents the nth initial defect measurement value. Represents the predicted average value, and determines The measured value of the target defect.

9. The method for measuring defects in etched holes as described in claim 3, characterized in that, The calculation of the perimeter of the fitted shape for each of the N target monitoring holes of the M aperture types includes: Fitting determines the closed regular pattern formed by the outermost vertices of each of the N target monitoring holes with different apertures; Based on the closed regular pattern corresponding to each of the N target monitoring holes with different apertures and the perimeter calculation formula corresponding to the closed regular pattern, the perimeter of the fitted shape of each of the N target monitoring holes with different apertures is determined.

10. The method for measuring defects in etched holes as described in claim 9, characterized in that, The closed regular shape includes at least one of a circle, an ellipse, and a polygon.

11. A method for monitoring an etching cavity, characterized in that, include: The defect measurement value of the etched hole is determined by using the defect measurement method of any one of claims 1-10; Determine whether the measured value of the target defect exceeds the set threshold range; If so, it is determined that the etching cavity is in an abnormal working state during the current monitoring cycle; If not, then it is determined that the etching cavity is in normal working condition during the current monitoring cycle.

12. The monitoring method for the etching cavity as described in claim 11, characterized in that, The method for determining the set threshold range includes: In each of the Y sequentially executed detection cycles, the first and second detection defect measurement values ​​corresponding to the detection sheet are obtained; wherein, the detection sheet has multiple detection holes of at least one aperture, the detection holes are formed by etching, and the detection holes are divided into upper, middle and lower parts according to depth from shallow to deep; the first detection defect measurement value is determined when the detection sheet is planarized to a first detection set height, and the second detection defect measurement value is determined when the detection sheet is planarized to a second detection set height; the first detection set height is the middle part of the detection hole, and the second detection set height is the lower part of the detection hole; The detection threshold and detection threshold error are determined based on the first and second detection defect measurement values ​​in the Y detection cycles. The set threshold range is determined based on the detection threshold and the detection threshold error.

13. The monitoring method for the etching cavity as described in claim 12, characterized in that, The step of obtaining the first and second defect measurement values ​​corresponding to the detection piece in each of the Y sequentially executed detection cycles includes: The detection piece is formed during the y-th detection cycle of the Y detection cycles; The detection piece is flattened to the first detection set height; Acquire a first detection image of the side of the detection plate with the detection hole at the first detection set height; Based on the perimeter of the fitted shape of the selected detection hole of the M apertures in the first detection image, the first detection defect measurement value corresponding to the y-th detection cycle is determined; The detection piece that has been flattened to the first detection set height is further flattened to the second detection set height. Acquire a second detection image of the target monitoring film at the second detection set height, on the side with the detection hole; Based on the perimeter of the fitted shape of the selected detection hole of the M apertures in the second detection image, the second detection defect measurement value corresponding to the y-th detection cycle is determined.

14. The monitoring method for the etching cavity as described in claim 13, characterized in that, The step of determining the first detection defect measurement value corresponding to the y-th detection cycle based on the perimeter of the fitted shape of the selected detection hole of the M apertures in the first detection image includes: From the M aperture detection holes in the first detection image, determine K first target detection holes corresponding to each aperture size; where K is an integer greater than 0; Calculate the perimeter of the fitted shape of each of the K first target detection holes of the M aperture sizes; Based on the perimeter of the fitted shape of each of the K first target detection holes of the M apertures, the first detection defect measurement value corresponding to the y-th detection cycle is determined.

15. The monitoring method for the etching cavity as described in claim 13 or 14, characterized in that, The step of determining the second detection defect measurement value corresponding to the y-th detection cycle based on the perimeter of the fitted shape of the selected detection hole of the M apertures in the second detection image includes: From the M aperture detection holes in the second detection image, determine K second target detection holes corresponding to each aperture size; where K is an integer greater than 0; Calculate the perimeter of the fitted shape of each of the K second target detection holes of the M aperture sizes; Based on the perimeter of the fitted shape of each of the K second target detection holes of the M apertures, the second detection defect measurement value corresponding to the y-th detection cycle is determined.

16. The monitoring method for the etching cavity as described in any one of claims 12-14, characterized in that, The set threshold range is j is an integer greater than 0. σ represents the detection threshold, and σ represents the detection threshold error.

17. A defect measuring device for etched holes, characterized in that, include: A planarization processing device is configured to acquire a target monitoring sheet and planarize the target monitoring sheet to a set monitoring height. The target monitoring sheet has multiple monitoring holes of M different apertures, which are formed by etching, where M is an integer greater than 0. The monitoring holes are divided into upper, middle, and lower parts according to their depth from shallow to deep, and the set monitoring height is located at the upper part of the monitoring holes. An image acquisition device is configured to acquire a monitoring image of the side of the target monitoring panel at the set monitoring height that has the monitoring hole. The defect measurement device is configured to determine the target defect measurement value based on the perimeter of the fitted shape of the monitoring hole of the M aperture sizes in the monitoring image.

18. A monitoring device for an etching cavity, characterized in that, include: A planarization processing device is configured to acquire a target monitoring sheet and planarize the target monitoring sheet to a set monitoring height. The target monitoring sheet has multiple monitoring holes of M different apertures, which are formed by etching, where M is an integer greater than 0. The monitoring holes are divided into upper, middle, and lower parts according to their depth from shallow to deep, and the set monitoring height is located at the upper part of the monitoring holes. An image acquisition device is configured to acquire a monitoring image of the side of the target monitoring panel at the set monitoring height that has the monitoring hole. The defect measurement device is configured to determine the target defect measurement value based on the perimeter of the fitted shape of the monitoring hole of the M aperture sizes in the monitoring image; The data processing device is configured to determine whether the measured value of the target defect exceeds a set threshold range; If so, it is determined that the etching cavity is in an abnormal working state during the current monitoring cycle; If not, then it is determined that the etching cavity is in normal working condition during the current monitoring cycle.

Images