WO2023206633A1

WO2023206633A1 - Measurement image detection method, apparatus, semiconductor device, and storage medium

Info

Publication number: WO2023206633A1
Application number: PCT/CN2022/092945
Authority: WO
Inventors: 刘文奇
Original assignee: 长鑫存储技术有限公司
Priority date: 2022-04-24
Filing date: 2022-05-16
Publication date: 2023-11-02
Also published as: CN116977244A

Abstract

A measurement image detection method, an apparatus, a semiconductor device, and a storage medium, relating to the technical field of semiconductors. The detection method is used in a semiconductor device, the detection method comprising: acquiring a first scanning electron microscope image of a mask layer located on the top of a semiconductor structure (S110); acquiring a second scanning electron microscope image of at least one semiconductor device layer of the semiconductor structure except the mask layer (S120); respectively projecting at least one image of the first scanning electron microscope image and the second scanning electron microscope image to a preset area of a wafer so as to form an alignment pattern (S130).

Description

Detection methods, devices, semiconductor equipment and storage media for measurement images

This disclosure is based on a Chinese patent application with application number 202210435336.5, the filing date is April 24, 2022, and the application name is "Detection method, device, semiconductor equipment and storage medium for measuring images", and requires that the Chinese patent application Priority, the entire content of this Chinese patent application is hereby incorporated by reference into this disclosure.

Technical field

The present disclosure relates to, but is not limited to, a detection method, device, semiconductor equipment and storage medium for measuring a measurement image.

Background technique

Semiconductor structures often contain multiple layers of patterned material, where each current layer must be aligned with the previous layer within tolerances. The overlay registration error between the current layer and the previous layer of the semiconductor structure is the overlay error, also called the overlay error. Among them, the overlay error describes the deviation of the current layer's pattern from the previous layer's pattern along the wafer surface and the distribution of this deviation on the wafer surface. Overlay error is a key indicator for testing the quality of the photolithography process.

Contents of the invention

The following is an overview of the subject matter described in detail in this disclosure. This summary is not intended to limit the scope of the claims.

The present disclosure provides a detection method, device, semiconductor equipment and storage medium for measuring images.

A first aspect of the present disclosure provides a method for detecting measurement images, which is applied to semiconductor equipment. The method for detecting measurement images includes:

Obtaining a first scanning electron microscope image of a mask layer located on top of the semiconductor structure;

Obtaining a second scanning electron microscope image of at least one semiconductor device layer of the semiconductor structure except the mask layer;

Project at least one of the first scanning electron microscope image and the second scanning electron microscope image to a preset area of the wafer to form an alignment pattern.

According to some embodiments of the present disclosure, obtaining a first scanning electron microscope image of a mask layer located on the top layer of the semiconductor structure includes:

Emitting first primary electrons toward the mask layer;

Obtain the secondary electrons reflected back by the mask layer;

The first SEM image is determined based on the secondary electrons.

According to some embodiments of the present disclosure, the emission energy of the first primary electron is greater than or equal to a preset energy value.

According to some embodiments of the present disclosure, obtaining a second scanning electron microscope image of at least one semiconductor device layer of the semiconductor structure except the mask layer includes:

Obtain the depth of the semiconductor device layer;

According to the depth of the semiconductor device layer, emitting second primary electrons matching the depth of the semiconductor device layer to the semiconductor device layer;

receiving backscattered electrons escaping from the surface of the semiconductor device layer;

Based on the backscattered electrons, a second scanning electron microscope image of the semiconductor device layer is determined.

According to some embodiments of the present disclosure, emitting second primary electrons to the semiconductor device layer that matches the depth of the semiconductor device layer according to the depth of the semiconductor device layer includes:

Obtain configuration information, the configuration information being used to characterize the corresponding relationship between the depth of the semiconductor device layer and the emission energy of the second primary electron;

determining the emission energy of the second primary electron according to the depth of the semiconductor device layer and the configuration information;

The second primary electrons are emitted toward the semiconductor device layer.

According to some embodiments of the present disclosure, projecting at least one of the first scanning electron microscope image and the second scanning electron microscope image to a preset area of the wafer to form an alignment pattern includes:

Establishing a one-to-one correspondence between the plurality of mark images of the second scanning electron microscope image and the plurality of semiconductor device layers;

Project a plurality of the mark images to the preset area respectively, wherein the plurality of mark images are respectively staggered;

Project the first scanning electron microscope image onto one of the plurality of mark images so that the first scanning electron microscope image overlaps with one of the mark images to form the alignment pattern;

or,

Project a plurality of the mark images to the preset area respectively, wherein the plurality of mark images overlap to form an overlapping mark;

The first scanning electron microscope image is projected onto the coincidence mark to form the alignment pattern.

According to some embodiments of the present disclosure, the detection method of the measurement image further includes:

Get weight information;

According to the weight information, the positions of the first scanning electron microscope image and the mark image or the overlapping mark are adjusted.

A second aspect of the present disclosure provides a detection device for measuring images, which is applied to semiconductor equipment. The detection device includes:

An acquisition module, configured to acquire a first scanning electron microscope image of the mask layer located on the top layer of the semiconductor structure;

The acquisition module is also used to acquire a second scanning electron microscope image of at least one semiconductor device layer of the semiconductor structure except the mask layer;

A projection module, configured to project at least one of the first scanning electron microscope image and the second scanning electron microscope image to a preset area of the wafer to form an alignment pattern.

According to some embodiments of the present disclosure, the acquisition module includes:

A first emission unit configured to emit first primary electrons to the mask layer;

A first acquisition unit configured to acquire secondary electrons reflected back by the mask layer;

A first determining unit configured to determine the first scanning electron microscope image according to the secondary electrons.

a second determination unit configured to obtain the depth of the semiconductor device layer;

a second emission unit configured to emit second primary electrons matching the depth of the semiconductor device layer to the semiconductor device layer according to the depth of the semiconductor device layer;

a second acquisition unit configured to receive backscattered electrons escaping from the surface of the semiconductor device layer;

The second determination unit is further configured to determine a second scanning electron microscope image of the semiconductor device layer based on the backscattered electrons.

According to some embodiments of the present disclosure, the second determining unit is used for:

The second primary electrons are emitted toward the semiconductor device layer.

According to some embodiments of the present disclosure, the projection module is used for:

or,

According to some embodiments of the present disclosure, the acquisition module is also used to:

Get weight information;

The projection module is also used to:

A third aspect of the present disclosure provides a semiconductor device, the semiconductor device including:

processor;

Memory used to store instructions executable by the processor;

Wherein, the processor is configured to execute the detection method of the measurement image as described in the first aspect.

A fourth aspect of the present disclosure provides a non-transitory computer-readable storage medium that, when instructions in the storage medium are executed by a processor of a semiconductor device, enables the semiconductor device to perform the measurement image as described in the first aspect detection method.

Other aspects will be apparent after reading and understanding the drawings and detailed description.

Description of the drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and, together with the description, serve to explain principles of the embodiments of the disclosure. In the drawings, similar reference numbers are used to identify similar elements. The drawings in the following description are of some, but not all, embodiments of the disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without exerting creative efforts.

FIG. 1 is a flow chart of a method for detecting measurement images according to an exemplary embodiment.

FIG. 2 is a flow chart for acquiring a first scanning electron microscope image in a method for detecting measurement images according to an exemplary embodiment.

FIG. 3 is a flow chart for acquiring a second scanning electron microscope image in a method for detecting measurement images according to an exemplary embodiment.

FIG. 4 is a flowchart of forming an alignment pattern in a method for detecting measurement images according to an exemplary embodiment.

FIG. 5 is a schematic structural diagram of a wafer on which a semiconductor structure is located according to an exemplary embodiment.

FIG. 6 is a schematic structural diagram of a semiconductor structure according to an exemplary embodiment.

7 is a top view of a first scanning electron microscope image according to an exemplary embodiment.

8 is a top view of a second scanning electron microscope image according to an exemplary embodiment.

FIG. 9 is a schematic diagram showing respectively projecting the first scanning electron microscope image and the second scanning electron microscope image to a preset area of the wafer according to an exemplary embodiment.

FIG. 10 is a schematic diagram of an alignment pattern formed by a first scanning electron microscope image and a second scanning electron microscope image according to an exemplary embodiment.

FIG. 11 is a top view of an alignment pattern formed on a semiconductor structure according to an exemplary embodiment.

FIG. 12 is a schematic structural diagram of a semiconductor structure according to an exemplary embodiment.

Figure 13 is a top view of a second scanning electron microscope image according to an exemplary embodiment.

Figure 14 is a top view of a marker image according to an exemplary embodiment.

Figure 15 is a top view of an alignment pattern according to an exemplary embodiment.

FIG. 16 is a schematic diagram illustrating multiple mark images forming a superimposed image according to an exemplary embodiment.

FIG. 17 is a schematic diagram of a first scanning electron microscope image projected onto a coincident mark according to an exemplary embodiment.

Figure 18 is a top view of an alignment pattern according to an exemplary embodiment.

FIG. 19 is a block diagram of a detection device for measuring images according to an example.

FIG. 20 is a block diagram of a semiconductor device for measuring images according to an example.

Reference signs:

1. Wafer; 11. Central area; 12. Edge area; 2. Semiconductor structure; 20. Semiconductor device layer; 20a, first semiconductor device layer; 20b, second semiconductor device layer; 20c, third semiconductor device layer; 3. Cutting area; 4. Mask layer; 100, first scanning electron microscope image; 200, second scanning electron microscope image; 200a, second scanning electron microscope image of the first semiconductor device layer; 200b, second scanning electron microscope image of the second semiconductor device layer Second scanning electron microscope image; 200c, second scanning electron microscope image of the third semiconductor device layer; 300, alignment pattern; 400, marking image; 410, first marking image; 420, second marking image; 430, third marking Image; 500, coincidence mark; 601, acquisition module; 602, projection module; 700, semiconductor device; 701, processor; 702, memory.

Detailed ways

In order to make the purpose, technical solutions and advantages of the disclosed embodiments more clear, the technical solutions in the disclosed embodiments will be clearly and completely described below in conjunction with the drawings in the disclosed embodiments. Obviously, the described embodiments These are some embodiments of the present disclosure, but not all embodiments. Based on the embodiments in this disclosure, all other embodiments obtained by those skilled in the art without making creative efforts fall within the scope of protection of this disclosure. It should be noted that, as long as there is no conflict, the embodiments and features in the embodiments can be arbitrarily combined with each other.

The present disclosure provides a measurement image detection method, which is applied to semiconductor equipment. In the semiconductor manufacturing process, the measurement image detection method provided by the present disclosure is applied to the detection of the mask layer before forming the target semiconductor device layer, and the mask layer is The first scanning electron microscope image of the film layer is aligned with the second scanning electron microscope image of the semiconductor device layer of the semiconductor structure, thereby obtaining an alignment pattern of the mask layer and the previous layer, and accurately measuring the accuracy of the mask layer.

In an exemplary embodiment, the exemplary embodiment of the present disclosure provides a detection method for measuring images, which is applied to semiconductor equipment. As shown in Figure 1, the detection method includes the following steps:

S110: Obtain a first scanning electron microscope image of the mask layer located on the top layer of the semiconductor structure.

As shown in FIG. 5 , the semiconductor structure 2 is located in the wafer 1 , and the semiconductor structure 2 may be a chip, for example. The wafer 1 includes a central area 11 and an edge area 12 surrounding the central area 11. The wafer 1 includes a plurality of semiconductor structures 2. The plurality of semiconductor structures 2 are arrayed in the central area 11 of the wafer 1. The adjacent semiconductor structures 2 are Separated by cutting lane area 3.

As shown in FIG. 6 , the semiconductor structure 2 includes at least one semiconductor device layer 20 . When the semiconductor structure 2 includes multiple semiconductor device layers 20 , the multiple semiconductor device layers 20 are stacked. A mask layer 4 is provided, and the mask layer 4 is disposed on the top surface of the semiconductor structure 2 to be measured (with the top in the orientation shown in FIG. 6 as the top). The mask layer 4 is used in the subsequent process of the semiconductor structure 2 , used to assist in forming the next semiconductor device layer 20.

Referring to FIG. 7 , a first scanning electron microscope image 100 of the mask layer 4 is obtained by scanning the mask layer 4 with a scanning electron microscope. The first scanning electron microscope image 100 shows the mask pattern of the mask layer 4 .

S120: Obtain a second scanning electron microscope image of at least one semiconductor device layer of the semiconductor structure except the mask layer.

As shown in FIG. 8 , a second scanning electron microscope image 200 is obtained by scanning the semiconductor structure 2 with a scanning electron microscope. The second scanning electron microscope image 200 is a scanning electron microscope image of the semiconductor device layer. When the semiconductor structure 2 includes multiple semiconductor device layers, by adjusting the scanning The radio frequency power of the electron microscope adjusts the energy of the electrons emitted by the scanning electron microscope, thereby changing the scanning depth of the scan to obtain a second scanning electron microscope image 200 of different layers of semiconductor device layers.

S130: Project at least one of the first scanning electron microscope image and the second scanning electron microscope image to a preset area of the wafer to form an alignment pattern.

As shown in FIGS. 9 and 10 , one or more second SEM images 200 are projected onto the preset area of the wafer 1 , and then the first SEM images 100 are projected onto the preset area of the wafer 1 . The SEM image 100 is superimposed on one or more second SEM images 200 to form an alignment pattern 300 . The first SEM image 100 and the second SEM image 200 form one or more pairs in a preset area of the wafer 1 Quasi pattern 300. In one example, as shown in FIG. 5 , the preset area of the wafer 1 may be located at the edge area 12 or the dicing lane area 3 of the wafer 1 .

In one example, the semiconductor structure 2 includes n layers of semiconductor device layers 20 arranged sequentially from the top surface of the semiconductor structure 2 downward, n≥2, and n is a positive integer. Scan the semiconductor structure 2 with a scanning electron microscope to obtain n second scanning electron microscopy images 200, project the n second scanning electron microscopy images 200 to preset areas of the wafer 1, and then project the first scanning electron microscopy images 100 n times respectively. Project the first SEM image 100 to n second SEM images 200 in the projection area of the wafer 1 to form n alignment patterns 300 to align the mask patterns of the mask layer 4 with n layers of semiconductors respectively. The alignment accuracy of the device layer 20 is tested.

In another example, n second SEM images 200 are obtained by scanning the semiconductor structure 2 with a SEM, and the n second SEM images 200 are projected to the same preset area of the wafer 1 to form n second SEM images. The first scanning electron microscope image 100 is then projected onto the superimposed image of n second scanning electron microscope images 200 to form an alignment pattern 300, and the mask pattern of the mask layer 4 is aligned with the semiconductor device layer 20 Alignment is performed, and at the same time, the alignment accuracy between the n-layer semiconductor device layers 20 is also detected.

The measurement image detection method of this embodiment uses scanning electron microscopy technology to obtain scanning electron microscope images of the mask layer and at least one semiconductor device layer. The scanning electron microscope images have high definition, and the mask layer and at least one semiconductor device layer are The alignment pattern formed by the scanning electron microscope image has higher definition, enabling the measurement of the overlay error of the mask layer and the pattern of at least one semiconductor device layer, improving the measurement accuracy and improving the product yield.

According to an exemplary embodiment, this embodiment is an illustration of the implementation of the above step S110. As shown in Figure 2, during the implementation process, a method of obtaining a first scanning electron microscope image of a mask layer located on the top layer of a semiconductor structure is provided. Includes the following steps:

Step S111: Emit first primary electrons to the mask layer.

The scanning electron microscope device emits an electron beam of first primary electrons to the surface of the mask layer 4. The first primary electrons collide with the electrons on the surface of the mask layer 4, and the electrons on the surface of the mask layer 4 are excited and release secondary electrons.

In this embodiment, the emission energy of the first primary electron is greater than or equal to the preset energy value. The preset energy value is a critical energy value that can excite the mask layer 4 so that the surface of the mask layer 4 is excited to release secondary electrons.

Step S112: Obtain the secondary electrons reflected back by the mask layer.

The secondary electrons released by the mask layer 4 are collected on the surface of the mask layer 4, and the number of secondary electrons at the corresponding position of the electron beam of each beam of first primary electrons is detected. There is a mask pattern on the mask layer 4. The edge of the mask pattern releases a larger number of secondary electrons. The number of secondary electrons at the corresponding position of the electron beam of each first primary electron is detected so that the subsequent steps can be based on different The number of secondary electrons in the position forms the first SEM image 100 .

Step S113: Determine the first scanning electron microscope image based on the secondary electrons.

In this embodiment, the first scanning electron microscope image 100 can be determined by a SE (Secondary electrons, secondary electrons) detector. The SE detector determines each of the first scanning electron microscope images 100 according to the number of secondary electrons at different positions. With the brightness of the pixel, the number of secondary electrons released from the edge of the mask pattern is greater, so the edge of the mask pattern will appear brighter in the first SEM image. As shown in FIG. 7 , the formed first scanning electron microscope image 100 provides the surface topography of the mask layer 4 , showing the topography information and feature size of the mask pattern.

The measurement image detection method of this embodiment emits first primary electrons to the mask layer, and different positions of the mask layer are excited by the first primary electrons to release different numbers of secondary electrons, thereby obtaining the amount of secondary electrons released by the mask layer. secondary electrons, and form a surface topography of the mask layer based on the acquired secondary electrons. The surface topography of the mask layer includes a mask pattern and feature sizes. The first scanning electron microscopy image obtained by the measurement image detection method of this embodiment has higher clarity, so as to improve the clarity of the alignment pattern formed by the subsequent scanning electron microscopy images of the mask layer and at least one semiconductor device layer.

According to an exemplary embodiment, this embodiment is an explanation of the implementation of the above step S120. As shown in FIG. 3, during the implementation process, the third layer of at least one semiconductor device layer of the semiconductor structure except the mask layer is obtained. 2. Scanning electron microscopy images, including the following steps:

S121: Obtain the depth of the semiconductor device layer.

Referring to FIG. 6 , the distance between the semiconductor device layer 20 to be detected and the top surface of the semiconductor structure 2 is obtained as the depth of the semiconductor device layer 20 .

S122: According to the depth of the semiconductor device layer, second primary electrons matching the depth of the semiconductor device layer are emitted to the semiconductor device layer.

The electron beam of the second primary electron is emitted to a preset depth of the semiconductor structure 2 through the scanning electron microscope device, so that the electron beam of the second primary electron is incident into the target semiconductor device layer 20 .

In this embodiment, according to the depth of the semiconductor device layer 20 , when second primary electrons matching the depth of the semiconductor device layer 20 are emitted to the semiconductor device layer 20 , configuration information is first obtained, and the configuration information is used to characterize the semiconductor device layer 20 The corresponding relationship between the depth and the emission energy of the second primary electron, and then according to the depth and configuration information of the semiconductor device layer 20, query the emission energy of the second primary electron corresponding to the depth of the semiconductor device layer 20 in the configuration information, and then determine The emission energy of the second primary electron corresponding to the depth of the current semiconductor device layer is obtained, and the second primary electron is emitted to the semiconductor device layer 20 with the emission energy of the second primary electron.

S123: Receive backscattered electrons escaping from the surface of the semiconductor device layer.

The electrons inside the material in the semiconductor device layer 20 reflect or scatter out the backscattered electrons from the surface of the semiconductor structure 2 after absorbing the energy of the second primary electron. When the semiconductor device layer 20 includes a variety of different materials, different materials have different abilities to absorb second primary electrons, and the energy of the escaped backscattered electrons is different. The surface of the semiconductor device layer 20 receives back energy of different materials escaped from different materials. Scattered electrons.

S124: Determine the second scanning electron microscope image of the semiconductor device layer based on the backscattered electrons.

In this embodiment, in the process of determining the second scanning electron microscope image 200 of the semiconductor device layer 20 based on backscattered electrons, the following method may be used:

The received backscattered electrons of different energies pass through fluorescent materials such as scintillators to convert the backscattered electrons of different energies into photoelectrons of different brightness. A driving voltage is applied to the photoelectrons to adjust the light and dark contrast of the photoelectrons, and then the photoelectrons are The second scanning electron microscope image 200 can be obtained by performing amplification processing. As shown in Figure 8, the second scanning electron microscope image 200 is a material composition diagram of the semiconductor device layer 20 formed according to backscattered electrons of different energies.

Among them, scintillator is a type of material that can emit light after absorbing high-energy particles or rays.

In one embodiment, as shown in FIG. 12 , from the top surface of the semiconductor structure 2 (taking the top in the orientation shown in the figure as the top) downward, the first semiconductor device layer 20 a and the second semiconductor device layer are sequentially arranged. layer 20b and the third semiconductor device layer 20c, then in step S121, the distance between the first semiconductor device layer 20a and the top surface of the semiconductor structure 2 is sequentially obtained as the depth of the first semiconductor device layer 20a, and the distance of the second semiconductor device layer 20b is obtained. The distance from the top surface of the semiconductor structure 2 is taken as the depth of the second semiconductor device layer 20b, and the distance between the third semiconductor device layer 20c and the top surface of the semiconductor structure 2 is taken as the depth of the third semiconductor device layer 20c.

Then, steps S122 to S124 are repeated. As shown in FIGS. 12 and 13 , second primary electrons with a first energy matching the first semiconductor device layer 20a are emitted to the semiconductor structure 2 to obtain the first semiconductor device layer 20a. The second scanning electron microscope image 200a; emit second primary electrons with the second energy that match the second semiconductor device layer 20b to the semiconductor structure 2, and obtain the second scanning electron microscope image 200b of the second semiconductor device layer 20b; to the semiconductor structure 2 2. Emit second primary electrons with a third energy that match the third semiconductor device layer 20c, and obtain a second scanning electron microscope image 200c of the third semiconductor device layer 20c.

The measurement image detection method of this embodiment emits second primary electrons with energy matching the depth of the semiconductor device layer to the semiconductor structure through the corresponding relationship between the depth of the semiconductor device layer and the emission energy of the second primary electron, Different materials have different energies of backscattered electrons that escape after being absorbed by the second primary electrons. According to the acquired backscattered electrons of different energies, a second scanning electron microscope image of the semiconductor device layer is formed; in this embodiment, multi-layer semiconductor devices can be acquired at one time According to the depth of the layer, second primary electrons with energies matching the depths of the semiconductor device layers of different layers are emitted multiple times to the semiconductor structure to obtain the second scanning electron microscope image of the multi-layer semiconductor device layer, thereby reducing the number of scans and saving scanning time.

According to an exemplary embodiment, this embodiment is an illustration of the implementation of the above step S130. As shown in Figure 4, during the implementation process, at least one of the first scanning electron microscope image and the second scanning electron microscope image is separately Projecting onto a preset area of the wafer to form an alignment pattern includes the following steps:

Step S131: Establish a one-to-one correspondence between the plurality of mark images of the second scanning electron microscope image and the plurality of semiconductor device layers.

As shown in FIG. 12 , FIG. 13 and FIG. 14 , when the semiconductor structure 2 includes a multi-layer semiconductor device layer 20 , a second scanning electron microscope image 200 of the multi-layer semiconductor device layer 20 is obtained respectively, and the multi-layer semiconductor device layer 20 and a plurality of The second scanning electron microscope image 200 establishes a one-to-one correspondence to facilitate subsequent measurement and observation of the formed mark image 400 .

In one embodiment, as shown in Figure 12, the semiconductor structure includes a first semiconductor device layer 20a, a second semiconductor device layer 20b and a third semiconductor device layer 20c. As shown in Figures 13 and 14, the first semiconductor device layer 20a, the second semiconductor device layer 20b and the third semiconductor device layer 20c. The marking image 400 formed by the projection of the second scanning electron microscope image 200 of the device layer 20a, the second semiconductor device layer 20b and the third semiconductor device layer 20c corresponds to the first marking image 410, the second marking image 420 and the third marking image 430.

Step S132: Project multiple mark images to preset areas respectively, wherein the multiple mark images are respectively staggered.

In one example, as shown in FIG. 11 and FIG. 14 , the preset area may be located in the scribe lane area 3 of the wafer 1 . That is, the detection method of this embodiment is applied to the scribe line area 3 between adjacent semiconductor structures 2, and the mark image 400 is disposed in the scribe line area 3 of the wafer 1, which can avoid subsequent alignment on the mark image 400. The quasi-pattern 300 affects the semiconductor structure 2 in the central area 11 of the wafer 1 and at the same time makes full use of the space of the wafer 1 to improve the utilization rate of the wafer 1 .

Step S133: Project the first scanning electron microscope image onto one of the plurality of mark images, so that the first scanning electron microscope image and the one mark image overlap to form an alignment pattern.

As shown in Figure 15, referring to Figure 14, the first scanning electron microscope image 100 is projected onto the mark image 400, so that the first scanning electron microscope image 100 overlaps a mark image 400, and a mask layer 4 corresponding to the mark image 400 is formed. Alignment pattern 300 of semiconductor device layer 20 .

According to an exemplary embodiment, this embodiment is an illustration of the implementation of the above step S130. During the implementation, at least one of the first scanning electron microscope image and the second scanning electron microscope image is respectively projected onto the predetermined area of the wafer. Setting the area to form the alignment pattern also includes the following steps:

Step S134: Project multiple mark images to preset areas respectively, where the multiple mark images overlap to form overlapping marks.

As shown in FIGS. 16 and 17 , referring to FIG. 14 , two or three of the first mark image 410 , the second mark image 420 , and the third mark image 430 can be projected at the same position to form an overlapping mark 500 . The mark 500 is a mark formed by two or three of the first semiconductor device layer 20a, the second semiconductor device layer 20b and the third semiconductor device layer 20c. The stacking of the multi-layer semiconductor device layer 20 can be measured by overlapping the mark 500. Accuracy.

Step S135: Project the first scanning electron microscope image onto the overlay mark to form an alignment pattern.

As shown in FIG. 18 , referring to FIG. 17 , the first SEM image 100 is projected onto the overlay mark 500 , so that the first SEM image 100 and the overlay mark 500 are overlaid to form the mask layer 4 and the multilayer semiconductor device layer 20 . Align pattern 300.

In this embodiment, as shown in Figures 14-17, in order to improve the alignment accuracy and ensure the measurement accuracy of the alignment pattern 300, the first scanning electron microscope image 100 is projected onto the mark image 400, and the weight information is also considered, After the weight information is obtained, the positions of the first scanning electron microscope image 100 and the mark image 400 or the overlapping mark 500 are adjusted according to the weight information.

When the first SEM image 100 is projected onto the mark image 400, the projection position may deviate from the mark image 400. Obtain the deviation direction and deviation distance of the first SEM image 100 from the mark image 400 each time it is projected onto the mark image 400. , superimpose the deviation direction and deviation distance of each projection to obtain the weight information. When the first SEM image 100 is projected onto the mark image 400, the projection position of the first SEM image 100 is adjusted according to the weight information, so that the first SEM image 100 is projected onto the mark image 400 and coincides with the mark image 400, The alignment accuracy of the alignment pattern 300 is improved. In this embodiment, weight information is obtained each time the first scanning electron microscope image 100 is projected onto the mark image 400, and in subsequent projections, the first scanning electron microscope image 100 is projected according to the previous weight information, so that the first scanning electron microscope image 100 can accurately project to the location of the marked image 400, improving alignment accuracy and reducing the number of projections.

The measurement image detection method of this embodiment can project the first scanning electron microscope image onto a mark image to form an alignment pattern, or can project the first scanning electron microscope image onto overlapping marks of multiple mark images to form an alignment pattern. , that is, the mask pattern of the mask layer and the pattern of a semiconductor device layer can be aligned and measured, or the mask pattern of the mask layer and the pattern of a multi-layer semiconductor device layer can be aligned and measured, It can also perform registration measurement on the patterns of multi-layer semiconductor device layers. Various alignment measurement methods improve the measurement accuracy and measurement flexibility.

In an exemplary embodiment, as shown in Figure 19, a detection device for measuring images is provided, which is applied to semiconductor equipment. The detection device for measuring images includes:

The acquisition module 601 is used to acquire a first scanning electron microscope image of the mask layer located on the top layer of the semiconductor structure.

The acquisition module 601 is also used to acquire a second scanning electron microscope image of at least one semiconductor device layer except the mask layer of the semiconductor structure.

The projection module 602 is configured to project at least one of the first scanning electron microscope image and the second scanning electron microscope image to a preset area of the wafer to form an alignment pattern.

In an exemplary embodiment, the acquisition module includes:

The first emission unit is used to emit first primary electrons to the mask layer.

The first acquisition unit is used to acquire the secondary electrons reflected back by the mask layer.

The first determination unit is used to determine the first scanning electron microscope image according to the secondary electrons.

In an exemplary embodiment, the acquisition module includes:

The second determination unit is used to obtain the depth of the semiconductor device layer.

The second emission unit is configured to emit second primary electrons matching the depth of the semiconductor device layer to the semiconductor device layer according to the depth of the semiconductor device layer.

The second acquisition unit is used to receive backscattered electrons escaping from the surface of the semiconductor device layer.

The second determination unit is also used to determine the second scanning electron microscope image of the semiconductor device layer based on the backscattered electrons.

Obtain configuration information, which is used to characterize the corresponding relationship between the depth of the semiconductor device layer and the emission energy of the second primary electron.

Based on the depth and configuration information of the semiconductor device layer, the emission energy of the second primary electron is determined.

Second primary electrons are emitted toward the semiconductor device layer.

In an exemplary embodiment, the projection module is used to:

A one-to-one correspondence between the plurality of mark images of the second scanning electron microscope image and the plurality of semiconductor device layers is established.

Project multiple mark images to preset areas respectively, where the multiple mark images are respectively staggered.

The first scanning electron microscope image is projected onto a mark image among the plurality of mark images, so that the first scanning electron microscope image and the one mark image are overlapped to form an alignment pattern.

or,

Project multiple mark images to preset areas respectively, where the multiple mark images overlap to form overlapping marks.

Project the first SEM image onto the coincident mark to form an alignment pattern.

In an exemplary embodiment, the acquisition module is also used to:

Get weight information.

The projection module is also used for:

FIG. 20 is a block diagram of a semiconductor device, that is, a semiconductor device 700 according to an exemplary embodiment. For example, the semiconductor device 700 may be provided as a terminal device. Referring to FIG. 20 , a semiconductor device 700 includes a processor 701 , and the number of processors can be set to one or more as needed. Semiconductor device 700 also includes memory 702 for storing instructions, such as application programs, executable by processor 701 . The number of memories can be set to one or more as needed. The stored applications can be one or more. The processor 701 is configured to execute instructions to execute the above-mentioned method of detecting measurement images.

It should be understood by those skilled in the art that embodiments of the present disclosure may be provided as methods, apparatuses (devices), or computer program products. Accordingly, the present disclosure may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment that combines software and hardware aspects. Furthermore, the present disclosure may take the form of a computer program product embodied on one or more computer-usable storage media having computer-usable program code embodied therein. Computer storage media includes volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data , including but not limited to RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, Digital Versatile Disk (DVD) or other optical disk storage, magnetic cassettes, tapes, disk storage or other magnetic storage devices, or may be used Any other medium that stores the desired information and can be accessed by the computer, etc. Furthermore, it is known to those of skill in the art that communication media typically embodies computer readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transport mechanism and may include any information delivery media.

In an exemplary embodiment, a non-transitory computer-readable storage medium including instructions, such as a memory 702 including instructions, executable by the processor 701 of the semiconductor device 700 to complete the steps illustrated in the above embodiments is provided. Detection method for measuring images. For example, the non-transitory computer-readable storage medium may be ROM, random access memory (RAM), CD-ROM, magnetic tape, floppy disk, optical data storage device, etc.

A non-transitory computer-readable storage medium that, when instructions in the storage medium are executed by a processor of a semiconductor device, enables the semiconductor device to perform:

Each embodiment or implementation mode in this specification is described in a progressive manner. Each embodiment focuses on its differences from other embodiments. The same and similar parts between various embodiments can be referred to each other.

In the description of this specification, reference to the description of the terms "embodiments," "exemplary embodiments," "some embodiments," "illustrative embodiments," "examples," etc. is intended to be described in connection with the embodiments or examples. A specific feature, structure, material, or characteristic is included in at least one embodiment or example of the present disclosure.

In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

In the description of the present disclosure, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present disclosure and simplifying the description. It does not indicate or imply that the indicated device or element must have a specific orientation or a specific orientation. construction and operation, and therefore should not be construed as limitations on the present disclosure.

It will be understood that the terms "first", "second", etc. used in this disclosure may be used to describe various structures in this disclosure, but these structures are not limited by these terms. These terms are used only to distinguish one structure from another.

In one or more of the figures, identical elements are designated with similar reference numbers. For the sake of clarity, various parts of the figures are not to scale. Additionally, some well-known parts may not be shown. For the sake of simplicity, the structure obtained after several steps can be described in one figure. Many specific details of the present disclosure are described below, such as device structures, materials, dimensions, processing processes and techniques, to provide a clearer understanding of the present disclosure. However, as one skilled in the art will appreciate, the present disclosure may be practiced without these specific details.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present disclosure, but not to limit it; although the present disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that it can still be used Modifications are made to the technical solutions described in the foregoing embodiments, or equivalent substitutions are made to some or all of the technical features; however, these modifications or substitutions do not cause the essence of the corresponding technical solutions to depart from the scope of the technical solutions of the embodiments of the present disclosure.

Industrial applicability

In the measurement image detection method, device, semiconductor equipment and storage medium provided by the embodiments of the present disclosure, the detection method obtains the scanning electron microscope image of the mask layer and at least one semiconductor device layer through a scanning electron microscope, and the scanning electron microscope image has high definition Therefore, the alignment pattern formed by the scanning electron microscope image of the mask layer and at least one semiconductor device layer is clearer, which improves the clarity of the measurement image and the measurement accuracy; and, while improving the measurement accuracy, through one scan Scanned images of multiple previous layers can be obtained, which can also improve the efficiency of measurement calculations, reduce expenses, and reduce costs.

Claims

A method for detecting measurement images, applied to semiconductor equipment, the method for detecting measurement images includes:

Obtaining a first scanning electron microscope image of a mask layer located on top of the semiconductor structure;

Obtaining a second scanning electron microscope image of at least one semiconductor device layer of the semiconductor structure except the mask layer;

Project at least one of the first scanning electron microscope image and the second scanning electron microscope image to a preset area of the wafer to form an alignment pattern.
The method for detecting measurement images according to claim 1, wherein said obtaining the first scanning electron microscope image of the mask layer located on the top layer of the semiconductor structure includes:

Emitting first primary electrons toward the mask layer;

Obtain the secondary electrons reflected back by the mask layer;

The first SEM image is determined based on the secondary electrons.
The method for detecting a measurement image according to claim 2, wherein the emission energy of the first primary electron is greater than or equal to a preset energy value.
The method for detecting measurement images according to claim 1, wherein said obtaining a second scanning electron microscope image of at least one semiconductor device layer of the semiconductor structure except the mask layer includes:

Obtain the depth of the semiconductor device layer;

According to the depth of the semiconductor device layer, emitting second primary electrons matching the depth of the semiconductor device layer to the semiconductor device layer;

receiving backscattered electrons escaping from the surface of the semiconductor device layer;

Based on the backscattered electrons, a second scanning electron microscope image of the semiconductor device layer is determined.
The method for detecting measurement images according to claim 4, wherein the second primary electrons matching the depth of the semiconductor device layer are emitted to the semiconductor device layer according to the depth of the semiconductor device layer, include:

Obtain configuration information, the configuration information being used to characterize the corresponding relationship between the depth of the semiconductor device layer and the emission energy of the second primary electron;

determining the emission energy of the second primary electron according to the depth of the semiconductor device layer and the configuration information;

The second primary electrons are emitted toward the semiconductor device layer.
The method for detecting measurement images according to claim 1, wherein the projecting at least one image of the first scanning electron microscope image and the second scanning electron microscope image to a preset area of the wafer forms a Alignment patterns, including:

Establishing a one-to-one correspondence between the plurality of mark images of the second scanning electron microscope image and the plurality of semiconductor device layers;

Project a plurality of the mark images to the preset area respectively, wherein the plurality of mark images are respectively staggered;

Project the first scanning electron microscope image onto one of the plurality of mark images so that the first scanning electron microscope image overlaps with one of the mark images to form the alignment pattern;

or,

Project a plurality of the mark images to the preset area respectively, wherein the plurality of mark images overlap to form an overlapping mark;

The first scanning electron microscope image is projected onto the coincidence mark to form the alignment pattern.
The method for detecting measurement images according to claim 6, wherein the method for detecting measurement images further includes:

Get weight information;

According to the weight information, the positions of the first scanning electron microscope image and the mark image or the overlapping mark are adjusted.
A detection device for measuring images, applied to semiconductor equipment, the device for detecting measurement images includes:

An acquisition module, configured to acquire a first scanning electron microscope image of the mask layer located on the top layer of the semiconductor structure;

The acquisition module is also used to acquire a second scanning electron microscope image of at least one semiconductor device layer of the semiconductor structure except the mask layer;

A projection module, configured to project at least one of the first scanning electron microscope image and the second scanning electron microscope image to a preset area of the wafer to form an alignment pattern.
The detection device for measuring images according to claim 8, wherein the acquisition module includes:

A first emission unit configured to emit first primary electrons to the mask layer;

A first acquisition unit configured to acquire secondary electrons reflected back by the mask layer;

A first determining unit configured to determine the first scanning electron microscope image according to the secondary electrons.
The detection device for measuring images according to claim 8, wherein the acquisition module includes:

a second determination unit configured to obtain the depth of the semiconductor device layer;

a second emission unit configured to emit second primary electrons matching the depth of the semiconductor device layer to the semiconductor device layer according to the depth of the semiconductor device layer;

a second acquisition unit configured to receive backscattered electrons escaping from the surface of the semiconductor device layer;

The second determination unit is further configured to determine a second scanning electron microscope image of the semiconductor device layer based on the backscattered electrons.
The detection device for measuring images according to claim 10, wherein the second determination unit is used for:

Obtain configuration information, the configuration information being used to characterize the corresponding relationship between the depth of the semiconductor device layer and the emission energy of the second primary electron;

determining the emission energy of the second primary electron according to the depth of the semiconductor device layer and the configuration information;

The second primary electrons are emitted toward the semiconductor device layer.
The detection device for measuring images according to claim 8, wherein the projection module is used for:

Establishing a one-to-one correspondence between the plurality of mark images of the second scanning electron microscope image and the plurality of semiconductor device layers;

Project a plurality of the mark images to the preset area respectively, wherein the plurality of mark images are respectively staggered;

Project the first scanning electron microscope image onto one of the plurality of mark images so that the first scanning electron microscope image overlaps with one of the mark images to form the alignment pattern;

or,

Project a plurality of the mark images to the preset area respectively, wherein the plurality of mark images overlap to form an overlapping mark;

The first scanning electron microscope image is projected onto the coincidence mark to form the alignment pattern.
The detection device for measuring images according to claim 12, wherein the acquisition module is also used for:

Get weight information;

The projection module is also used to:

According to the weight information, the positions of the first scanning electron microscope image and the mark image or the overlapping mark are adjusted.
A semiconductor device, the semiconductor device includes:

processor;

Memory used to store instructions executable by the processor;

Wherein, the processor is configured to execute the measurement image detection method according to any one of claims 1 to 7.
A non-transitory computer-readable storage medium that, when instructions in the storage medium are executed by a processor of a semiconductor device, enables the semiconductor device to perform the measurement of the image as claimed in any one of claims 1 to 7 Detection method.