CN117830195A

CN117830195A - Detection method and device, storage medium and electronic equipment

Info

Publication number: CN117830195A
Application number: CN202211203802.3A
Authority: CN
Inventors: 宫凯歌
Original assignee: Changxin Memory Technologies Inc
Current assignee: Changxin Memory Technologies Inc
Priority date: 2022-09-29
Filing date: 2022-09-29
Publication date: 2024-04-05
Also published as: WO2024065980A1

Abstract

The present disclosure relates to an overlapping state detection method, an overlapping state detection device, a mask detection method, a mask detection device, a computer-readable storage medium, and an electronic apparatus. The overlapping state detection method comprises the following steps: preparing a first patterning material layer; acquiring a first image corresponding to a designated area of a first patterning material layer; preparing a second patterned material layer; acquiring a second image corresponding to the appointed area of the second patterning material layer; and performing image registration on the first image and the second image according to the corresponding relation between the first design layout of the first patterning material layer and the second design layout of the second patterning material layer so as to acquire the overlapping state of the first patterning material layer and the second patterning material layer. The method for acquiring the overlapping state is capable of accurately judging the design condition of the mask.

Description

Detection method and device, storage medium and electronic equipment

Technical Field

The present disclosure relates to the technical field of integrated circuits, and in particular, to an overlapping state detection method, an overlapping state detection device, a mask detection method, a mask detection device, a computer readable storage medium, and an electronic device.

Background

In the fabrication of semiconductor devices, patterning information is typically transferred to a product substrate through a reticle to form various layers of patterning material. However, due to the existence of optical proximity effect, the design accuracy of the mask needs to be detected, which is usually achieved by detecting the overlapping state (or alignment state) of the patterned material layers of two adjacent layers.

However, the existing method based on the overlapped state is difficult to eliminate the offset problem caused by the process, so that whether the mask design has a problem cannot be judged according to the overlapped state.

It should be noted that the information disclosed in the above background section is only for enhancing understanding of the background of the present disclosure and thus may include information that does not constitute prior art known to those of ordinary skill in the art.

Disclosure of Invention

The disclosure aims to provide an overlapping state detection method, an overlapping state detection device, a mask detection method, a mask detection device, a computer readable storage medium and electronic equipment, and provides an overlapping state acquisition method for accurately judging a mask design condition.

Other features and advantages of the present disclosure will be apparent from the following detailed description, or may be learned in part by the practice of the invention.

According to a first aspect of the present disclosure, there is provided an overlap state detection method including: preparing a first patterning material layer; acquiring a first image corresponding to a designated area of the first patterning material layer; preparing a second patterned material layer; acquiring a second image corresponding to the appointed area of the second patterning material layer, wherein the appointed area of the second patterning material layer corresponds to the position of the appointed area of the first patterning material layer; and carrying out image registration on the first image and the second image according to the corresponding relation between the first design layout of the first patterning material layer and the second design layout of the second patterning material layer so as to obtain the overlapping state of the first patterning material layer and the second patterning material layer.

In an exemplary embodiment of the present disclosure, the performing image registration on the first image and the second image according to a correspondence between a first design layout of the first patterning material layer and a second design layout of the second patterning material layer includes: performing image registration on the first image and a designated area of the first design layout; performing image registration on the second image and a designated area of the second design layout; and superposing the first image and the second image according to the corresponding relation between the first design layout and the second design layout.

In an exemplary embodiment of the present disclosure, the registering the first image with the designated area of the first design layout includes: extracting a first edge feature of the first image; and carrying out image registration on the first edge feature and the designated area of the first design layout.

In an exemplary embodiment of the present disclosure, the registering the first edge feature with the designated area of the first design layout includes: aligning the gravity center of an image formed by the first edge features with the gravity center of an image of a designated area of the first design layout; and aligning the first edge feature with a reference point or a reference line of a designated area of the first design layout.

In an exemplary embodiment of the present disclosure, the registering the second image with the designated area of the second design layout includes: extracting a second edge feature of the second image; and carrying out image registration on the second edge feature and the appointed area of the second design layout.

In an exemplary embodiment of the present disclosure, the registering the second edge feature with the designated area of the second design layout includes: aligning the gravity center of the image formed by the second edge features with the gravity center of the image of the appointed area of the second design layout; and aligning the second edge feature with a reference point or a reference line of a designated area of the second design layout.

In an exemplary embodiment of the present disclosure, the acquiring the overlapping state of the first patterned material layer and the second patterned material layer includes: superposing the first edge feature and the second edge feature; acquiring process window values corresponding to the first edge feature and the second edge feature; and judging whether the process window value is within an allowable preset range.

In an exemplary embodiment of the present disclosure, the method further comprises: acquiring a plurality of groups of first images and second images; acquiring a plurality of groups of first edge features and second edge features according to the plurality of groups of first images and the second images; and obtaining the average value of a plurality of groups of process window values corresponding to the first edge feature and the second edge feature.

In one exemplary embodiment of the present disclosure, the second patterned material layer and the first patterned material layer are disposed adjacent to or spaced apart from each other.

According to a second aspect of the present disclosure, there is provided a reticle inspection method, including: acquiring the overlapping state of the first patterning material layer and the second patterning material layer according to the overlapping state detection method; and judging whether the mask design layout has a design problem according to the overlapping state.

In an exemplary embodiment of the present disclosure, the method further comprises: acquiring a plurality of mask design layouts, and determining a process window value corresponding to each mask design layout according to the overlapping state determined by each mask design layout; and determining the mask design layout with the maximum process window value as a target mask design layout.

In an exemplary embodiment of the present disclosure, the determining whether the mask design layout has a design problem according to the overlapping state includes: and if the process window values corresponding to the first patterning material layer and the second patterning material layer exceed the allowable preset range, judging that the mask design layout has a design problem.

In an exemplary embodiment of the present disclosure, the method further comprises: if the second patterned material layer is the current layer of the wafer and the first patterned material layer is the front layer of the wafer, determining that the mask design layout of the second patterned material layer has a design problem.

According to a third aspect of the present disclosure, there is provided an overlapping state detection apparatus including: a first image acquisition module for preparing a first patterned material layer; acquiring a first image corresponding to a designated area of the first patterning material layer; a second image acquisition module for preparing a second patterned material layer; acquiring a second image corresponding to the appointed area of the second patterning material layer, wherein the appointed area of the second patterning material layer corresponds to the position of the appointed area of the first patterning material layer; and the overlapping state acquisition module is used for carrying out image registration on the first image and the second image according to the first design layout of the first patterning material layer and the second design layout of the second patterning material layer so as to acquire the overlapping state of the first patterning material layer and the second patterning material layer.

According to a fourth aspect of the present disclosure, there is provided a reticle inspection device, comprising: the overlapping state acquisition module is used for acquiring the overlapping state of the first patterning material layer and the second patterning material layer through the overlapping state detection device; and the judging module is used for judging whether the mask design layout has a design problem according to the overlapping state.

According to a fifth aspect of the present disclosure, there is provided a computer readable storage medium having stored thereon a computer program which, when executed by a processor, implements the method described above.

According to a sixth aspect of the present disclosure, there is provided an electronic device comprising: a processor; and a memory for storing executable instructions of the processor; wherein the processor is configured to perform the above-described method via execution of the executable instructions.

The technical scheme provided by the disclosure can comprise the following beneficial effects:

according to the overlapping state detection method provided by the exemplary embodiment of the disclosure, the first patterning material layer is prepared, the first image corresponding to the designated area of the first patterning material layer is obtained, and after the second patterning material layer is prepared, the second image corresponding to the designated area of the second patterning material layer is obtained, and because the designated area of the second patterning material layer corresponds to the position of the designated area of the first patterning material layer, namely the first image corresponds to the second image, the first image and the second image can be subjected to image registration according to the corresponding relation between the first design layout of the first patterning material layer and the second design layout of the second patterning material layer; because the offset problem of the process is not existed between the first design layout and the second design layout, the offset problem caused by the process can be greatly reduced according to the overlapped state of the first patterning material layer and the second patterning material layer obtained by registering the first image and the second image, and whether the mask design layout for forming the first patterning material layer or the second patterning material layer is problematic can be judged according to the overlapped state.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the disclosure and together with the description, serve to explain the principles of the disclosure. It will be apparent to those of ordinary skill in the art that the drawings in the following description are merely examples of the disclosure and that other drawings may be derived from them without undue effort. In the drawings:

FIG. 1 schematically illustrates a schematic view of an exposure process;

FIG. 2 schematically illustrates a flow chart of steps of a method of overlap condition detection according to an exemplary embodiment of the present disclosure;

FIG. 3 schematically illustrates a first image corresponding to a designated area of a first patterned material layer in a wafer;

fig. 4 schematically illustrates a schematic diagram of a second image obtained corresponding to a designated area of the second patterned material layer in the wafer;

FIG. 5 schematically illustrates a first edge feature corresponding to the first image shown in FIG. 3;

FIG. 6 schematically illustrates a second edge feature corresponding to the second image shown in FIG. 4;

FIG. 7 schematically illustrates a schematic view of the first edge feature of FIG. 5 superimposed with the second edge feature of FIG. 6;

FIGS. 8 and 9 schematically illustrate the overlapping of the first and second patterned material layers corresponding to two different mask design layouts;

FIG. 10 schematically illustrates an overlapping state acquisition process in an exemplary embodiment of the present disclosure;

FIG. 11 schematically illustrates a step flow diagram of a reticle inspection method according to an example embodiment of the present disclosure;

fig. 12 schematically illustrates a block diagram of an overlapping state detection apparatus according to an exemplary embodiment of the present disclosure;

FIG. 13 schematically illustrates a block diagram of a reticle inspection device according to an example embodiment of the disclosure;

fig. 14 schematically illustrates a block diagram of an electronic device according to an exemplary embodiment of the present disclosure.

Detailed Description

Example embodiments will now be described more fully with reference to the accompanying drawings. However, the exemplary embodiments can be embodied in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the example embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar parts, and thus a repetitive description thereof will be omitted.

Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a thorough understanding of embodiments of the disclosure. One skilled in the relevant art will recognize, however, that the disclosed aspects may be practiced without one or more of the specific details, or with other methods, components, devices, steps, etc. In other instances, well-known structures, methods, devices, implementations, materials, or operations are not shown or described in detail to avoid obscuring aspects of the disclosure.

The block diagrams depicted in the figures are merely functional entities and do not necessarily correspond to physically separate entities. That is, these functional entities may be implemented in software, or in one or more software-hardened modules, or in different networks and/or processor devices and/or microcontroller devices.

In the manufacture of semiconductor devices, the transfer of a photomask pattern formed on a semiconductor wafer is mainly performed by repeating a photolithography process and an etching process. In the transfer printing process of the photomask pattern, a mask plate is needed, and the mask plate is a graph master plate used in a photoetching process commonly used in micro-nano processing technology. A mask pattern structure is formed on a transparent substrate by an opaque light-shielding film, and pattern information is transferred to a product substrate through an exposure process. In the process of transferring the pattern information on the mask plate to the product substrate, due to the effects of optical proximity and the like, the optical pattern formed by the mask plate and the pattern of the mask plate have deviation, so that the photoetching pattern on the product substrate and the pattern of the mask plate are inconsistent. Therefore, the design pattern of the mask plate needs to be adjusted for correction.

Existing computer systems commonly employ inexpensive, high density DRAM (Dynamic Random Access Memory ) as system memory, also known as memory. The DRAM mainly uses a mask plate to make patterned material layers layer by layer on a silicon wafer, wherein the first patterned material layer can be called a front layer, and the later patterned material layer can be called a current layer.

Under the condition that the manufacturing process meets the requirements, whether the mask has a problem or not can be judged through the overlapping state of the front layer and the current layer, and the method is equivalent to judging whether the mask design layout has the problem or not. The overlapping state herein refers to the degree of alignment of the two-layer patterns, including both cases of alignment and misalignment.

In the overlapping state measurement process, the BSE (Backscattered electron ) signals of the High Voltage SEM machine can be used to obtain overlapping images of the front layer and the current layer, and the overlapping state of the front layer and the current layer can be judged according to the overlapping images. In the overlapping image acquisition process, the overlapping images of the front layer and the current layer are obtained mainly by penetrating the current layer through the back scattering electronic signals to shoot the front layer.

In the above process of acquiring the overlapped state, at least the following problems exist: first, in the process of penetrating the back-scattered electron signal into the layer, the thickness of the layer is required not to be too thick, and if the thickness is too thick, the back-scattered electron signal cannot penetrate; the second point is that the offset problem caused by the process is difficult to be eliminated by the overlapping state determined by the overlapping images, and even if the two layers of images are not aligned by the overlapping state, the non-aligned state cannot be determined due to the problem of the mask design layout; the third point is that only overlapping images of two adjacent patterned material layers can be generally obtained through back scattering electronic signals, overlapping images of two spaced patterned material layers can not be obtained, and overlapping images of multiple patterned material layers can not be obtained; fourth, the High Voltage SEM machine is expensive to manufacture, resulting in a significant increase in the cost of acquiring the overlap condition.

Based on the above-described problems, a new overlap state detection method is provided in an exemplary embodiment of the present disclosure.

Although the following description is primarily exemplified as a DRAM device, those skilled in the art will appreciate that the claimed disclosure may be implemented to support any semiconductor product requiring reticle pattern transfer.

The fabrication of each semiconductor product typically requires hundreds of processes, and the overall fabrication process can be generally divided into eight steps: wafer processing-oxidation-lithography-etching-thin film deposition-interconnect-testing-packaging. Photolithography, among other things, is the "printing" of circuit patterns onto a wafer by light, which is understood to mean the drawing of a plan view, i.e. a layer of patterned material, on the surface of the wafer, which is required for semiconductor manufacturing. The higher the fineness of the circuit pattern, the higher the integration of the finished chip, and thus, it is required to be realized by advanced photolithography techniques. In particular, photolithography can be divided into three steps of coating photoresist, exposing and developing.

The first step in patterning the circuitry on the wafer is to coat photoresist on the oxide layer. The photoresist makes the wafer a "photo" by changing the chemistry. The thinner the photoresist layer on the wafer surface, the more uniform the coating, and the finer the pattern that can be printed. This step may employ a "spin-on" method. After the wafer is covered with the photoresist film, the circuit printing can be accomplished by controlling the light irradiation, a process called "exposure". Light may be selectively passed by an exposure apparatus to print circuits onto a wafer having a photoresist film coated underneath as the light passes through a reticle containing circuit patterns, a schematic of an exposure process is shown with reference to fig. 1.

The finer the printed pattern during exposure, the more components the final chip can accommodate, which helps to increase production efficiency and reduce the cost of individual components. The exposure is followed by spraying a developer onto the wafer to remove the photoresist from the uncovered areas of the pattern, thereby allowing the printed circuit pattern to appear.

That is, the pattern on the reticle can be transferred to the wafer through the photolithography step, thereby forming a patterned material layer on the wafer.

In practical applications, in order to check whether there is a problem in designing a mask, that is, in checking whether there is a problem in designing a mask, it is generally necessary to obtain whether a patterned material layer drawn by the mask is aligned with a patterned material layer drawn before, that is, to check the overlapping state of at least two patterned material layers drawn.

Referring to fig. 2, a flowchart of steps of an overlap state detection method of an exemplary embodiment of the present disclosure is shown. As shown in fig. 2, the overlapping state detection method provided in the exemplary embodiment of the present disclosure mainly includes the following steps:

step S210, preparing a first patterning material layer;

step S220, a first image corresponding to a designated area of the first patterning material layer is obtained;

Step S230, preparing a second patterned material layer;

step S240, obtaining a second image corresponding to the appointed area of the second patterned material layer, wherein the appointed area of the second patterned material layer corresponds to the position of the appointed area of the first patterned material layer;

step S250, performing image registration on the first image and the second image according to the corresponding relation between the first design layout of the first patterning material layer and the second design layout of the second patterning material layer so as to obtain the overlapping state of the first patterning material layer and the second patterning material layer.

On the other hand, in the overlapping state detection method provided in the exemplary embodiment of the present disclosure, in the process of acquiring the first image and the second image, since only the image of the current patterned material layer is acquired, there is no need to penetrate the current layer to acquire the image of the current layer, and thus, there is no requirement on the thickness of the layer, and the first image and the second image can be acquired by a common SEM (Scanning Electron Microscope ). That is, from another perspective, the first image and the second image are acquired without an expensive High Voltage SEM machine, so that the cost of acquiring the overlapped state can be reduced.

The overlapping state detection method will be described in detail with reference to the following embodiments:

in step S210, a first patterned material layer is prepared.

In practical applications, the process of preparing the first patterned material layer may refer to the above-mentioned photolithography steps, which are not described herein.

It should be noted that the first patterned material layer is prepared from a mask corresponding to the first design layout of the first patterned material layer.

In practical applications, the first design layout may exist in the form of a graphic database system file (Graphic Database System file, GDS), which is a "layout" file containing various design information for producing a mask corresponding to the first patterned material layer required for the photolithography process. Typically, the GDS file may be opened using a Klayout software.

In step S220, a first image corresponding to the designated area of the first patterned material layer is acquired.

After the first patterned material layer is prepared, an image of the first patterned material layer can be acquired as required, that is, a first image corresponding to a designated area of the first patterned material layer is acquired. The designated area may be a local area in the first patterned material layer selected by the user according to the need, or may be an entire area of the first patterned material layer, which is not limited by the exemplary embodiments of the present disclosure.

In particular, in acquiring the first image, an SEM Scanning Electron Microscope (SEM), which is a viewing means between a transmission electron microscope and an optical microscope, may be used for acquisition. The method uses a focused very narrow high-energy electron beam to scan the surface of a first patterning material layer, and excites various physical information through the interaction between the light beam and a substance, and the information is collected, amplified and re-imaged to achieve the aim of representing the microscopic morphology of the substance. Of course, the first image may be acquired using a High Voltage SEM machine without considering costs, which is not particularly limited in the exemplary embodiments of the present disclosure.

The first image represents an image of the surface of the first patterning material layer, i.e. an image obtained when the surface of the first patterning material layer is viewed from above.

In step S230, a second patterned material layer is prepared.

In practical applications, the process of preparing the second patterned material layer may refer to the above-mentioned photolithography step, which is not described herein.

It should be noted that the second patterned material layer is prepared from a mask corresponding to the second design layout of the second patterned material layer.

Likewise, the second design layout may also exist in the form of a graphic database system file GDS for producing a reticle corresponding to the second patterned material layer required for the photolithography process. Typically, the GDS file may be opened using a Klayout software.

In step S240, a second image corresponding to the designated area of the second patterned material layer is acquired, where the designated area of the second patterned material layer corresponds to the position of the designated area of the first patterned material layer.

After the second patterned material layer is prepared, an image of the second patterned material layer can be acquired as required, that is, a second image corresponding to the designated area of the second patterned material layer is acquired. The designated area may be a local area in the second patterned material layer selected by the user according to the need, or may be an entire area of the second patterned material layer, which is not limited by the exemplary embodiments of the present disclosure.

In particular, in acquiring the second image, an SEM Scanning Electron Microscope (SEM), which is a viewing means between a transmission electron microscope and an optical microscope, may be used for acquisition. The method uses a focused very narrow high-energy electron beam to scan the surface of a second patterned material layer, and excites various physical information through the interaction between the light beam and a substance, and the information is collected, amplified and re-imaged to achieve the aim of representing the microscopic morphology of the substance. Of course, the second image may be acquired using a High Voltage SEM machine without considering costs, which is not particularly limited in the exemplary embodiments of the present disclosure.

The second image represents an image of the surface of the second patterned material layer, i.e. an image obtained when the surface of the second patterned material layer is viewed from above.

In practical applications, to obtain the overlapping state of the first patterned material layer and the second patterned material layer, it is necessary to ensure that the positions of the designated area of the first patterned material layer and the designated area of the second patterned material layer correspond to each other, so as to overlap the two corresponding areas. In the exemplary embodiments of the present disclosure, in order to ensure that the positions of the designated areas of the first and second patterned material layers correspond, it is necessary to ensure that the photographing positions of the first and second patterned material layers are identical. For this reason, after the first patterning material layer shooting position is selected, the shooting position needs to be recorded, that is, the coordinates of the shooting position are recorded; when shooting the designated area of the second patterned material layer, reference is required to the coordinates of the shooting position of the first patterned material layer to ensure that the shooting position of the second patterned material layer corresponds to the shooting position of the first patterned material layer, that is, the acquired designated area of the first patterned material layer corresponds to the acquired designated area of the second patterned material layer.

In addition, in the exemplary embodiment of the present disclosure, in order to prevent the offset during the shooting process, an addressing process (address) needs to be performed on the SEM machine, and before shooting, the SEM machine may find the approximate sampling position, and then accurately find the required sampling coordinate position through the addressing process, so as to ensure that the position of the SEM machine will not be offset during the shooting process. Further ensuring that the shooting positions of the first patterning material layer and the second patterning material layer are consistent.

Referring to fig. 3, a first image corresponding to a designated area of a first patterned material layer in a certain wafer obtained by the above method is shown, and referring to fig. 4, a second image corresponding to a designated area of a second patterned material layer in the wafer obtained by the above method is shown.

In step S250, the first image and the second image are subjected to image registration according to the correspondence between the first design layout of the first patterned material layer and the second design layout of the second patterned material layer, so as to obtain the overlapping state of the first patterned material layer and the second patterned material layer.

In an exemplary embodiment of the present disclosure, performing image registration on a first image and a second image according to a correspondence between a first design layout of a first patterned material layer and a second design layout of a second patterned material layer includes: carrying out image registration on the first image and a designated area of the first design layout; carrying out image registration on the second image and a designated area of the second design layout; and superposing the first image and the second image according to the corresponding relation between the first design layout and the second design layout.

The image registration (Image registration) is a process of matching and overlapping two or more images acquired at different times, different sensors (imaging devices) or under different conditions (weather, illuminance, imaging position, angle, etc.).

In an exemplary embodiment of the present disclosure, performing image registration of a first image with a designated area of a first design layout includes: extracting first edge characteristics of a first image; and performing image registration on the first edge characteristic and the designated area of the first design layout. The image registration of the second image with the designated area of the second design layout includes: extracting a second edge feature of the second image; and performing image registration on the second edge feature and the designated area of the second design layout.

Where image edges are important features of an image, are those sets of pixels in the image where there is a discontinuity in the distribution of characteristics (e.g., pixel gray, texture, etc.) around the image, where there is a step change or ridge change in the characteristics. The edge portion of an image concentrates most of the information of the image, and the edge structure and characteristics of an image are often important parts for determining the characteristics of the image. Another definition of an image edge refers to a collection of pixels whose surrounding pixel gray level changes discontinuously. Edges are widely present between objects and backgrounds, objects and objects, and therefore edges are important features for image segmentation, image understanding, and image recognition.

The image edge detection is mainly used for enhancing contour edges, details and gray jump parts in the image to form a complete object boundary, so that the object is separated from the image or the area representing the surface of the same object is detected. The most common approach to date is to detect discontinuities in luminance values, which can be detected by either first derivative or second derivative. The first derivative is the position of the corresponding edge with the maximum value and the second derivative is the position of the corresponding edge with the zero crossing.

In practical application, the method for extracting the edge features can be as follows: the extraction of the first edge feature and the second edge feature in the exemplary embodiments of the present disclosure may use any of the above methods, and is not particularly limited herein. As shown in fig. 5, the first edge feature corresponding to the first image shown in fig. 3; as shown in fig. 6, is a second edge feature corresponding to the second image shown in fig. 4.

In the exemplary embodiment of the disclosure, after performing image registration on the first edge feature and the designated area of the first design layout and performing image registration on the second edge feature and the designated area of the second design layout, the first edge feature and the second edge feature may be directly overlapped.

In the exemplary embodiments of the present disclosure, due to the superposition of the first edge feature and the second edge feature, the superposition is mainly performed based on the correspondence between the first design layout of the first patterning material layer and the second design layout of the second patterning material layer. In the original design layout of the wafer, the designated area of the first design layout corresponds to the designated area of the second design layout. Because the alignment superposition between the design layouts is not affected by the process, the first edge feature and the second edge feature after registration can greatly reduce the offset problem of the first patterning material layer and the second patterning material layer caused in the process after superposition.

That is, after the first edge feature and the second edge feature are overlapped, the obtained overlapping state of the first patterned material layer and the second patterned material layer greatly reduces the offset problem of the first patterned material layer and the second patterned material layer caused in the process, and whether the mask plate of the first patterned material layer or the second patterned material layer has a design problem, that is, whether the mask design layout has a problem, can be directly judged based on the overlapping state. Referring to fig. 7, a schematic diagram is shown of the first edge feature of fig. 5 superimposed with the second edge feature of fig. 6.

In practical applications, there may be multiple methods for performing image registration between the first edge feature and the designated area of the first design layout. In the exemplary embodiment of the disclosure, the center of gravity of the image formed by the first edge features is aligned with the center of gravity of the image of the designated area of the first design layout; and aligning the first edge feature with a reference point or a reference line of a designated area of the first design layout.

The image is actually a matrix, the elements of each location are the pixels at that location, and the pixel value at each point in the image can be understood as the quality at that point. Since the image is a two-dimensional matrix, the center of gravity needs to be found independently in the x-direction and the y-direction, respectively. I.e. for the center of gravity in the x-direction, the pixels of the image on the left and right sides of the center of gravity are equal; for the center of gravity in the y-direction, the image is equal to the sum of pixels on both sides of the center of gravity. The gravity center position of the image can be determined according to the gravity center of the image in the x direction and the gravity center of the image in the y direction.

In the exemplary embodiment of the disclosure, the image barycenter formed by the first edge features is aligned with the image barycenter of the designated area of the first design layout, so that the offset problem between the images can be eliminated, and the accuracy of image alignment is improved. On the basis of aligning the gravity centers of the images, a plurality of reference points or reference lines can be determined at positions which are not easy to deform in the first edge features, so that the first edge features are aligned with the designated areas of the first design layout based on the reference points or the reference lines, and the purpose of accurate alignment is achieved. The specific positions of the reference points and the reference lines need to be determined according to specific images, and are not particularly limited herein.

Likewise, in the exemplary embodiment of the present disclosure, the image registration is performed between the second edge feature and the designated area of the second design layout, or the center of gravity of the image formed by the second edge feature may be aligned with the center of gravity of the image of the designated area of the second design layout; and aligning the second edge feature with a reference point or a reference line of a designated area of the second design layout. Specific alignment processes may be referred to the above description and will not be repeated here.

In practical application, the first design layout and the second design layout are corresponding, so that the first edge feature and the second edge feature which are respectively aligned with the first design layout and the second design layout can be directly overlapped and aligned. The superimposed first and second edge features may reflect the overlapping state of the first and second patterned material layers.

In practical applications, the overlapping state may have various metrics, for example, taking the process window value W as an example, the process window values corresponding to the first edge feature and the second edge feature may be obtained first, and whether the process window values are within the allowed preset range is determined. If the process window value is within the allowed preset range, the mask of the first patterning material layer and the mask of the second patterning material layer are free of design problems; if the process window value exceeds the allowable preset range, the method indicates that at least one mask plate in the mask plates corresponding to the first patterning material layer and the second patterning material layer has design problems. Wherein the process window value W may be as shown in fig. 7.

Taking fig. 7 as an example, the dots represent the first edge feature, the bar graph represents the second edge feature, and the shortest length of the dot boundary from the bar graph boundary is the process window value W of the first edge feature and the second edge feature. In practical applications, the edge feature may be other shapes, not necessarily dots or bar charts.

Because the overlapping state of the first patterned material layer and the second patterned material layer obtained by the overlapping state detection method provided by the exemplary embodiment of the present disclosure can be directly used for detecting the design problem of the mask, in the design process of the mask, it can also be determined which mask is better according to the obtained overlapping state of the first patterned material layer and the second patterned material layer, that is, which mask design layout is better than the mask which meets the requirements is determined, that is, a proper mask and the mask design layout corresponding to the proper mask are selected according to the overlapping state of the first patterned material layer and the second patterned material layer.

Specifically, in the mask design process, when the design condition of the mask is changed, that is, the mask design layout is changed, the overlapping state of the corresponding obtained first patterned material layer and the second patterned material layer also changes, and the process window value W of the corresponding first edge feature and second edge feature changes, that is, a more appropriate mask can be selected directly according to the size of the process window value W. Specifically, the larger the process window value W, the better the schedulable the corresponding mask, and the better the mask.

Referring to fig. 8 and 9, the overlapping states of the first patterned material layer and the second patterned material layer corresponding to two different mask design layouts are shown, where it is noted that the two different mask design layouts are used to produce the same mask. As can be seen from the process window value W1 shown in fig. 8 and the process window value W2 shown in fig. 9, W1 is significantly smaller than W2, that is, the scheme of the mask design layout corresponding to fig. 9 is better.

In the exemplary embodiment of the disclosure, in the process of acquiring the first image and the second image, multiple sets of the first image and the second image may be acquired, and multiple sets of the first edge feature and the second edge feature may be acquired according to the multiple sets of the first image and the second image. After the multiple sets of the first edge feature and the second edge feature are obtained, the first edge feature and the second edge feature of each set may be overlapped, and the specific overlapping manner may refer to the above description, which is not repeated herein.

After the first edge feature and the second edge feature of each group are overlapped, a plurality of groups of process window values corresponding to the first edge feature and the second edge feature can be obtained, and then, the process window values of the plurality of groups can be averaged, so that a more accurate process window value can be obtained. Further, the subsequent judgment analysis can be performed according to the average value of the process window value, for example, whether the average value of the process window value is within the allowable preset range or not is judged, if so, the corresponding mask is according with the requirement, and the like.

The method for detecting an overlapping state provided in the exemplary embodiment of the present disclosure does not require that the first patterned material layer and the second patterned material layer are adjacent, that is, in the exemplary embodiment of the present disclosure, the second patterned material layer and the first patterned material layer may be disposed adjacent or spaced apart, that is, the first patterned material layer and the second patterned material layer may be adjacent patterned material layers or spaced apart from other patterned material layers. Thereby making it possible to expand the range of use of the overlap state detection method.

Since the overlapping state detection method provided by the exemplary embodiments of the present disclosure has no special requirement on the positional relationship of the first patterned material layer and the second patterned material layer, the overlapping state detection method may detect not only the overlapping state of two patterned material layers but also the overlapping state of a plurality of patterned material layers, for example, the overlapping state of three patterned material layers, the overlapping state of four patterned material layers, and the like.

In the process of detecting the overlapping state of the three patterned material layers, besides the images corresponding to the first patterned material layer and the second patterned material layer, the images corresponding to the third patterned material layer are required to be obtained, the edge features corresponding to the images are extracted, and finally the three edge features are overlapped to obtain the overlapping state of the three patterned material layers. For the specific overlapping process, reference may be made to the above-mentioned process of overlapping the first edge feature and the second edge feature, which is not described herein again.

Referring to fig. 10, a schematic diagram of an overlapping state acquiring process in an exemplary embodiment of the present disclosure is shown, and in fig. 10, a first patterned material layer is acquired first, and then a first image corresponding to a designated area of the first patterned material layer is obtained; acquiring a second patterning material layer, and acquiring a second image corresponding to the appointed area of the second patterning material layer; the acquisition sequence of the first patterning material layer and the second patterning material layer is determined by the preparation sequence. Then, extracting a first edge feature of the first image and a second edge feature of the second image; and then, superposing the first edge feature and the second edge feature, and finally, obtaining the superposition state of the first patterning material layer and the second patterning material layer.

According to the overlapping state detection method provided by the exemplary embodiment of the disclosure, the first edge characteristic and the second edge characteristic corresponding to the first patterning material layer and the second patterning material layer are obtained; when the first edge feature and the second edge feature are overlapped, because the offset problem existing in the process is not existed between the first design layout and the second design layout, the offset problem caused by the process can be greatly reduced according to the overlapped state of the first patterning material layer and the second patterning material layer obtained by overlapping the first edge feature and the second edge feature, and whether the mask design layout for forming the first patterning material layer or the second patterning material layer is problematic can be judged according to the overlapped state. On the other hand, in the overlapping state detection method provided in the exemplary embodiment of the present disclosure, in the process of acquiring the first image and the second image, since only the image of the current patterned material layer is acquired, there is no need to penetrate the current layer to acquire the image of the current layer, and thus there is no requirement on the thickness of the layer. In still another aspect, the method for detecting an overlapping state provided by the exemplary embodiment of the present disclosure has no special requirement on a positional relationship between the first patterned material layer and the second patterned material layer, so that the method for detecting an overlapping state of two patterned material layers can detect an overlapping state of a plurality of patterned material layers, thereby expanding a range of application of the method for detecting an overlapping state.

Further, the exemplary embodiment of the present disclosure further provides a mask detection method, and referring to fig. 11, a flowchart illustrating steps of the mask detection method according to the exemplary embodiment of the present disclosure is shown. As shown in fig. 11, the mask detection method provided in the exemplary embodiment of the present disclosure mainly includes the following steps:

step S1110, obtaining an overlapping state of the first patterned material layer and the second patterned material layer according to the above-mentioned overlapping state detection method;

step S1120, judging whether the mask design layout has a design problem according to the overlapping state.

The method for obtaining the overlapping state of the first patterned material layer and the second patterned material layer has been described in detail in the foregoing embodiments, and will not be described herein again.

In an exemplary embodiment of the disclosure, whether a mask design layout has a design problem is determined according to an overlapping state, and whether the mask design layout has a design problem is determined mainly according to whether the obtained corresponding process window value is within an allowable preset range, if the process window values corresponding to the first patterned material layer and the second patterned material layer exceed the allowable preset range. The process window value acquisition has been described in detail in the foregoing embodiments, and is not described herein.

In the exemplary embodiment of the disclosure, multiple mask design layouts can be obtained according to different design conditions, and a process window value corresponding to each mask design layout is determined according to the determined overlapping state of each mask design layout; and determining the mask design layout with the maximum process window value as a target mask design layout. That is, the overlapping states obtained according to exemplary embodiments of the present disclosure may select an optimal mask design layout as a target mask design layout.

In practical application, a mask design layout of which patterning material layer is specifically judged to have a problem, and the qualified patterning material layer is mainly obtained according to which patterning material layer is a reference layer. The current layer is generally determined according to the previous layer, for example, if the second patterned material layer is the current layer of the wafer and the first patterned material layer is the previous layer of the wafer, then it is determined that the mask design layout of the second patterned material layer has a design problem.

In summary, in the exemplary embodiment of the disclosure, after the overlapping state between different patterned material layers is obtained, whether the corresponding mask design layout has a design problem may be determined based on the overlapping state, so that important experimental data support is provided for the design of the mask, and improvement of the mask design is facilitated.

It should be noted that although the steps of the method of the present invention are depicted in the drawings in a particular order, this does not require or imply that the steps must be performed in that particular order or that all of the illustrated steps be performed in order to achieve desirable results. Additionally or alternatively, certain steps may be omitted, multiple steps combined into one step to perform, and/or one step decomposed into multiple steps to perform, etc.

Further, in the present exemplary embodiment, there is also provided an overlapping state detecting apparatus. Referring to fig. 12, the overlapping state detecting apparatus 1200 may include: a first image acquisition module 1210, a second image acquisition module 1220, and an overlap state acquisition module 1230, wherein:

a first image acquisition module 1210 for preparing a first patterned material layer; acquiring a first image corresponding to a designated area of a first patterning material layer;

a second image acquisition module 1220 for preparing a second patterned material layer; acquiring a second image corresponding to the appointed area of the second patterning material layer, wherein the appointed area of the second patterning material layer corresponds to the appointed area of the first patterning material layer;

The overlapped state obtaining module 1230 is configured to perform image registration on the first image and the second image according to the first design layout of the first patterned material layer and the second design layout of the second patterned material layer, so as to obtain an overlapped state of the first patterned material layer and the second patterned material layer.

In an exemplary embodiment of the present disclosure, the overlapped state acquiring module 1230 is configured to perform image registration on the first image and a designated area of the first design layout; carrying out image registration on the second image and a designated area of the second design layout; and superposing the first image and the second image according to the corresponding relation between the first design layout and the second design layout.

In one exemplary embodiment of the present disclosure, an overlap state acquisition module 1230 for extracting a first edge feature of the first image; and carrying out image registration on the first edge characteristic and the designated area of the first design layout.

In an exemplary embodiment of the present disclosure, the overlapped state acquiring module 1230 is configured to align the center of gravity of the image formed by the first edge feature with the center of gravity of the image of the designated area of the first design layout; and aligning the first edge feature with a reference point or a reference line of a designated area of the first design layout.

In one exemplary embodiment of the present disclosure, an overlapping state acquisition module 1230 is used to extract a second edge feature of the second image; and carrying out image registration on the second edge feature and the designated area of the second design layout.

In an exemplary embodiment of the present disclosure, the overlapping state obtaining module 1230 is configured to align the center of gravity of the image formed by the second edge feature with the center of gravity of the image of the designated area of the second design layout; and aligning the second edge feature with a reference point or a reference line of a designated area of the second design layout.

In an exemplary embodiment of the present disclosure, an overlapping state acquisition module 1230 is configured to overlap the first edge feature and the second edge feature; acquiring process window values corresponding to the first edge feature and the second edge feature; and judging whether the process window value is within an allowable preset range.

In an exemplary embodiment of the present disclosure, an overlapping state acquisition module 1230 for acquiring a plurality of sets of first images and second images; acquiring a plurality of groups of first edge features and second edge features according to the plurality of groups of first images and second images; and obtaining average values of the process window values corresponding to the plurality of groups of first edge features and the second edge features.

In addition, in this example embodiment, a mask detection device is also provided. Referring to fig. 13, the reticle inspection device 1300 may include: an overlap state acquisition module 1310 and a determination module 1320, wherein:

an overlapped state obtaining module 1310, configured to obtain an overlapped state of the first patterned material layer and the second patterned material layer through the overlapped state detecting device;

a judging module 1320, configured to judge whether the mask design layout has a design problem according to the overlapping state.

In an exemplary embodiment of the present disclosure, a determining module 1320 is configured to obtain multiple mask design layouts, and determine a process window value corresponding to each mask design layout according to the overlapping state determined by each mask design layout; and determining the mask design layout with the maximum process window value as a target mask design layout.

In an exemplary embodiment of the present disclosure, the determining module 1320 is configured to determine that a mask design layout has a design problem if a process window value corresponding to the first patterned material layer and the second patterned material layer exceeds an allowable preset range.

In an exemplary embodiment of the present disclosure, the determining module 1320 is configured to determine that a mask design layout of the second patterned material layer has a design problem if the second patterned material layer is a current layer of the wafer and the first patterned material layer is a front layer of the wafer.

The details of the virtual modules on each device side in the foregoing description have been described in detail on the corresponding method side, and therefore, will not be described herein.

It should be noted that although several modules or units on the device side are mentioned in the above detailed description, this division is not mandatory. Indeed, the features and functionality of two or more modules or units described above may be embodied in one module or unit in accordance with embodiments of the present disclosure. Conversely, the features and functions of one module or unit described above may be further divided into a plurality of modules or units to be embodied.

In an exemplary embodiment of the present disclosure, an electronic device capable of implementing the above method is also provided.

Those skilled in the art will appreciate that the various aspects of the invention may be implemented as a system, method, or program product. Accordingly, aspects of the invention may be embodied in the following forms, namely: an entirely hardware embodiment, an entirely software embodiment (including firmware, micro-code, etc.) or an embodiment combining hardware and software aspects may be referred to herein as a "circuit," module "or" system.

An electronic device 1400 according to such an embodiment of the invention is described below with reference to fig. 14. The electronic device 1400 shown in fig. 14 is merely an example and should not be construed as limiting the functionality and scope of use of embodiments of the present invention.

As shown in fig. 14, the electronic device 1400 is embodied in the form of a general purpose computing device. Components of electronic device 1400 may include, but are not limited to: the at least one processing unit 1410, the at least one memory unit 1420, a bus 1430 connecting the different system components (including the memory unit 1420 and the processing unit 1410), and a display unit 1440.

Wherein said memory unit 1420 stores program code that can be executed by said processing unit 1410, such that said processing unit 1410 performs the steps according to various exemplary embodiments of the present invention described in the above-mentioned "exemplary method" section of the present specification. For example, the processing unit 1410 may perform step S210 as shown in fig. 2, preparing a first patterned material layer; step S220, a first image corresponding to a designated area of the first patterning material layer is obtained; step S230, preparing a second patterned material layer; step S240, obtaining a second image corresponding to the appointed area of the second patterned material layer, wherein the appointed area of the second patterned material layer corresponds to the position of the appointed area of the first patterned material layer; step S250, performing image registration on the first image and the second image according to the corresponding relation between the first design layout of the first patterning material layer and the second design layout of the second patterning material layer so as to obtain the overlapping state of the first patterning material layer and the second patterning material layer. Step S1110, as shown in fig. 11, may also be performed to acquire the overlapped state of the first patterned material layer and the second patterned material layer according to the above-described overlapped state detection method; step S1120, judging whether the mask design layout has a design problem according to the overlapping state.

The memory unit 1420 may include readable media in the form of volatile memory units, such as Random Access Memory (RAM) 14201 and/or cache memory 14202, and may further include Read Only Memory (ROM) 14203.

The memory unit 1420 may also include a program/utility 14204 having a set (at least one) of program modules 14205, such program modules 14205 including, but not limited to: an operating system, one or more application programs, other program modules, and program data, each or some combination of which may include an implementation of a network environment.

Bus 1430 may be a local bus representing one or more of several types of bus structures including a memory unit bus or memory unit controller, a peripheral bus, an accelerated graphics port, a processing unit, or using any of a variety of bus architectures.

The electronic device 1400 may also communicate with one or more external devices 1470 (e.g., keyboard, pointing device, bluetooth device, etc.), one or more devices that enable a user to interact with the electronic device 1400, and/or any device (e.g., router, modem, etc.) that enables the electronic device 1400 to communicate with one or more other computing devices. Such communication may occur through an input/output (I/O) interface 1450. Also, electronic device 1400 may communicate with one or more networks such as a Local Area Network (LAN), a Wide Area Network (WAN), and/or a public network, such as the Internet, through network adapter 1460. As shown, the network adapter 1460 communicates with other modules of the electronic device 1400 via the bus 1430. It should be appreciated that although not shown, other hardware and/or software modules may be used in connection with electronic device 1400, including, but not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, data backup storage systems, and the like.

From the above description of embodiments, those skilled in the art will readily appreciate that the example embodiments described herein may be implemented in software, or may be implemented in software in combination with the necessary hardware. Thus, the technical solution according to the embodiments of the present disclosure may be embodied in the form of a software product, which may be stored in a non-volatile storage medium (may be a CD-ROM, a U-disk, a mobile hard disk, etc.) or on a network, including several instructions to cause a computing device (may be a personal computer, a server, a terminal device, or a network device, etc.) to perform the method according to the embodiments of the present disclosure.

In an exemplary embodiment of the present disclosure, a computer-readable storage medium having stored thereon a program product capable of implementing the method described above in the present specification is also provided. In some possible embodiments, the various aspects of the invention may also be implemented in the form of a program product comprising program code for causing a terminal device to carry out the steps according to the various exemplary embodiments of the invention as described in the "exemplary methods" section of this specification, when said program product is run on the terminal device.

A program product for implementing the above-described method according to an embodiment of the present invention may employ a portable compact disc read-only memory (CD-ROM) and include program code, and may be run on a terminal device, such as a personal computer. However, the program product of the present invention is not limited thereto, and in this document, a readable storage medium may be any tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device.

The program product may employ any combination of one or more readable media. The readable medium may be a readable signal medium or a readable storage medium. The readable storage medium can be, for example, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or a combination of any of the foregoing. More specific examples (a non-exhaustive list) of the readable storage medium would include the following: an electrical connection having one or more wires, a portable disk, a hard disk, random Access Memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

The computer readable signal medium may include a data signal propagated in baseband or as part of a carrier wave with readable program code embodied therein. Such a propagated data signal may take any of a variety of forms, including, but not limited to, electro-magnetic, optical, or any suitable combination of the foregoing. A readable signal medium may also be any readable medium that is not a readable storage medium and that can communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device.

Program code embodied on a readable medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing.

Program code for carrying out operations of the present invention may be written in any combination of one or more programming languages, including an object oriented programming language such as Java, C++ or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code may execute entirely on the user's computing device, partly on the user's device, as a stand-alone software package, partly on the user's computing device, partly on a remote computing device, or entirely on the remote computing device or server. In the case of remote computing devices, the remote computing device may be connected to the user computing device through any kind of network, including a Local Area Network (LAN) or a Wide Area Network (WAN), or may be connected to an external computing device (e.g., connected via the Internet using an Internet service provider).

Furthermore, the above-described drawings are only schematic illustrations of processes included in the method according to the exemplary embodiment of the present invention, and are not intended to be limiting. It will be readily appreciated that the processes shown in the above figures do not indicate or limit the temporal order of these processes. In addition, it is also readily understood that these processes may be performed synchronously or asynchronously, for example, among a plurality of modules.

Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure disclosed herein. This application is intended to cover any adaptations, uses, or adaptations of the disclosure following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.

It is to be understood that the present disclosure is not limited to the precise arrangements and instrumentalities shown in the drawings, and that various modifications and changes may be effected without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. An overlap state detection method, comprising:

Preparing a first patterning material layer;

acquiring a first image corresponding to a designated area of the first patterning material layer;

preparing a second patterned material layer;

acquiring a second image corresponding to the appointed area of the second patterning material layer, wherein the appointed area of the second patterning material layer corresponds to the position of the appointed area of the first patterning material layer;

and carrying out image registration on the first image and the second image according to the corresponding relation between the first design layout of the first patterning material layer and the second design layout of the second patterning material layer so as to obtain the overlapping state of the first patterning material layer and the second patterning material layer.

2. The method of claim 1, wherein the image registering the first image and the second image according to a correspondence of a first design layout of the first patterned material layer and a second design layout of the second patterned material layer comprises:

performing image registration on the first image and a designated area of the first design layout;

performing image registration on the second image and a designated area of the second design layout;

And superposing the first image and the second image according to the corresponding relation between the first design layout and the second design layout.

3. The method of claim 2, wherein the image registering the first image with the designated area of the first design layout comprises:

extracting a first edge feature of the first image;

and carrying out image registration on the first edge feature and the designated area of the first design layout.

4. A method according to claim 3, wherein said image registering the first edge feature with a designated area of the first design layout comprises:

aligning the gravity center of an image formed by the first edge features with the gravity center of an image of a designated area of the first design layout;

and aligning the first edge feature with a reference point or a reference line of a designated area of the first design layout.

5. The method of claim 4, wherein the image registering the second image with the designated area of the second design layout comprises:

extracting a second edge feature of the second image;

And carrying out image registration on the second edge feature and the appointed area of the second design layout.

6. The method of claim 5, wherein the image registering the second edge feature with the designated area of the second design layout comprises:

aligning the gravity center of the image formed by the second edge features with the gravity center of the image of the appointed area of the second design layout;

and aligning the second edge feature with a reference point or a reference line of a designated area of the second design layout.

7. The method of claim 6, wherein the acquiring the overlap state of the first patterned material layer and the second patterned material layer comprises:

superposing the first edge feature and the second edge feature;

acquiring process window values corresponding to the first edge feature and the second edge feature;

and judging whether the process window value is within an allowable preset range.

8. The method of claim 7, wherein the method further comprises:

acquiring a plurality of groups of first images and second images;

acquiring a plurality of groups of first edge features and second edge features according to the plurality of groups of first images and the second images;

And obtaining the average value of a plurality of groups of process window values corresponding to the first edge feature and the second edge feature.

9. The method of any of claims 1-8, wherein the second patterned material layer and the first patterned material layer are disposed adjacent to or spaced apart from each other.

10. A mask detection method is characterized by comprising the following steps:

the overlapped state detection method according to any one of claims 1 to 9, wherein an overlapped state of the first patterned material layer and the second patterned material layer is obtained;

and judging whether the mask design layout has a design problem according to the overlapping state.

11. The method according to claim 10, wherein the method further comprises:

acquiring a plurality of mask design layouts, and determining a process window value corresponding to each mask design layout according to the overlapping state determined by each mask design layout;

and determining the mask design layout with the maximum process window value as a target mask design layout.

12. The method according to claim 10, wherein determining whether a mask design layout has a design problem according to the overlapping state comprises:

And if the process window values corresponding to the first patterning material layer and the second patterning material layer exceed the allowable preset range, judging that the mask design layout has a design problem.

13. The method according to claim 12, wherein the method further comprises:

if the second patterned material layer is the current layer of the wafer and the first patterned material layer is the front layer of the wafer, determining that the mask design layout of the second patterned material layer has a design problem.

14. An overlapping state detecting apparatus, comprising:

a first image acquisition module for preparing a first patterned material layer; acquiring a first image corresponding to a designated area of the first patterning material layer;

a second image acquisition module for preparing a second patterned material layer; acquiring a second image corresponding to the appointed area of the second patterning material layer, wherein the appointed area of the second patterning material layer corresponds to the position of the appointed area of the first patterning material layer;

and the overlapping state acquisition module is used for carrying out image registration on the first image and the second image according to the first design layout of the first patterning material layer and the second design layout of the second patterning material layer so as to acquire the overlapping state of the first patterning material layer and the second patterning material layer.

15. Mask detection device, characterized by, include:

an overlapped state acquisition module for acquiring an overlapped state of the first patterned material layer and the second patterned material layer by the overlapped state detection device of claim 14;

and the judging module is used for judging whether the mask design layout has a design problem according to the overlapping state.

16. A computer readable storage medium, on which a computer program is stored, characterized in that the computer program, when being executed by a processor, implements the method of any of claims 1-13.

17. An electronic device, comprising:

a processor; and

a memory for storing executable instructions of the processor;

wherein the processor is configured to perform the method of any of claims 1-13 via execution of the executable instructions.