A method and system for backside overlay accuracy verification and overlay error compensation

Abstract

The invention relates to the field of photolithography machines and discloses a backside overlay accuracy verification and overlay error compensation method, comprising the following steps: making a first overlay mark and a first scale around the first overlay mark on the front side of a transparent sheet; using a backside microscope to capture and save a mask template alignment mark, wherein the mask template alignment mark consists of a second overlay mark and a second scale around the second overlay mark; using the backside microscope to align the first scale and the second scale on the front side of the transparent sheet, and after alignment, exposing and developing a newly made mark; reading the first scale and the second scale on the newly made mark through an optical microscope, and obtaining the overlay accuracy through the degree of alignment of the first scale and the second scale.

Description

Technical Field

[0001] The present invention relates to the field of photolithography machines, and in particular to a back side overlay accuracy verification and overlay error compensation method and system. Background Art

[0002] The existing backside overlay verification method is to place the front side (with marks) of the silicon wafer downwards, align it through the backside alignment system, and then apply glue and expose it to the back side of the silicon wafer, so that both sides of the silicon wafer have marks. The overlay instrument uses infrared light to penetrate the silicon wafer to identify the front and back patterns and read the errors after overlay.

[0003] It can be seen that the existing technology requires both the front and back sides of the silicon wafer to be coated with glue and exposed, and requires professional equipment such as an overlay instrument to read the overlay error. Summary of the invention

[0004] The main purpose of the present invention is to solve the technical problem that a professional overlay instrument is required to read the overlay error in the prior art. The back overlay verification method used in the present invention is simple, efficient and timely, and does not require double-sided glue coating exposure. A back overlay accuracy verification and overlay error compensation method includes the following steps:

[0005] Making a first set of engraved marks and first scale marks around the first set of engraved marks on the front side of the transparent sheet;

[0006] Using a backside microscope to capture and save the mask alignment mark, wherein the mask alignment mark consists of a second set of engraved marks and a second scale around the second set of engraved marks;

[0007] Use a back-side microscope to align the first scale and the second scale on the front side of the transparent film, and after alignment, expose and develop the newly made marks;

[0008] The first scale and the second scale on the newly made mark are read through an optical microscope, and the overlay accuracy is obtained through the degree of alignment between the first scale and the second scale.

[0009] The first scales are 4 groups of scales surrounding the first set of engraved marks, which are respectively located directly above, directly below, directly left and directly right of the first set of engraved marks. The second scales are 4 groups of scales surrounding the second set of engraved marks, which are respectively located directly above, directly below, directly left and directly right of the second set of engraved marks. The scales directly above and directly below are used to read the horizontal overlay deviation, and the scales directly left and directly right are used to read the vertical overlay deviation.

[0010] In the first scale and the second scale, the interval between each scale is 0.01-2 μm.

[0011] The two new marks are made on the left and right sides of the transparent sheet at the same time to obtain the overlay error values ​​(Lx, Ly), (Rx, Ry) for compensating the overlay error. The compensation algorithm is:

[0012] δx=(Lx+Rx) / 2

[0013] δy=(Ly+Ry) / 2

[0014] δθ=arctan((Ry-Ly) / d)

[0015] Among them, δx and δy are the lateral overlay deviation and the longitudinal overlay deviation respectively, and δθ is the overlay deviation angle.

[0016] The scale on the newly made mark adopts intelligent recognition steps:

[0017] From left to right and from top to bottom, identify the four groups of scales arranged vertically, obtain the coordinates of the midpoints of the scale tips, and arrange them in order to obtain the first, second, third, and fourth horizontal coordinate sets;

[0018] The difference between the ordinates of any two sets of coordinates in the abscissa set;

[0019] The scale with the smallest difference is taken as the lateral overlay error value;

[0020] From top to bottom and from left to right, identify the four groups of scales arranged horizontally, obtain the coordinates of the midpoints of the scale tips, and arrange them in order to obtain the first, second, third, and fourth vertical coordinate sets;

[0021] Calculate the difference between the horizontal coordinates of any two sets of vertical coordinates;

[0022] The scale with the smallest difference is taken as the longitudinal overlay error value.

[0023] The intelligent identification step also includes a correction step:

[0024] Calculate the proportion of white pixels in the quadrilateral formed by the first and second horizontal coordinate sets, the third and fourth horizontal coordinate sets, the first and second vertical coordinate sets, and the third and fourth vertical coordinate sets, respectively, to obtain a first horizontal proportion, a second horizontal proportion, a first vertical proportion, and a second vertical proportion;

[0025] Correcting the longitudinal overlay error value according to the first horizontal ratio and the second horizontal ratio;

[0026] The lateral overlay error value is corrected according to the first longitudinal ratio and the second longitudinal ratio.

[0027] The correction algorithm uses the following formula:

[0028]

[0029] Wherein δx and δy are the lateral overlay error and the longitudinal overlay error, Ph1 and Ph2 are the first lateral ratio and the second lateral ratio, Pv1 and Pv2 are the first longitudinal ratio and the second longitudinal ratio, α and β are empirical coefficients, which control the amplitude of linear and high-order correction respectively.

[0030] A second aspect of the present invention provides a back side overlay accuracy verification and overlay error compensation system, the back side overlay accuracy verification and overlay error compensation system comprising:

[0031] A first engraving unit is used to make a first set of engraved marks and first scale marks around the first set of engraved marks on the front side of the transparent sheet;

[0032] an alignment unit, using a backside microscope to capture and save a mask alignment mark, wherein the mask alignment mark consists of a second set of engraved marks and a second scale around the second set of engraved marks;

[0033] The second engraving unit uses a back microscope to align the first scale and the second scale on the front side of the transparent sheet, and after alignment, exposes and develops the newly made marks;

[0034] The overlay accuracy reading unit reads the first scale and the second scale on the newly made mark through an optical microscope, and obtains the overlay accuracy through the alignment degree of the first scale and the second scale.

[0035] The third aspect of the present invention provides an electronic device, comprising: a memory and at least one processor, wherein instructions are stored in the memory, and the memory and the at least one processor are interconnected via lines; the at least one processor calls the instructions in the memory so that the electronic device executes the above-mentioned back side overlay accuracy verification and overlay error compensation method.

[0036] A fourth aspect of the present invention provides a computer-readable storage medium, wherein instructions are stored in the computer-readable storage medium, and when the computer-readable storage medium is run on a computer, the computer executes the above-mentioned back side overlay accuracy verification and overlay error compensation method.

[0037] The present invention has the following beneficial effects:

[0038] The present invention makes the back overlay accuracy verification method more convenient and quick by using a transparent sheet and a special alignment mark, and can quickly read the overlay accuracy and compensate the alignment system. It is convenient and quick, and does not require expensive overlay equipment and a microscope with a measuring function. The back overlay verification method used by the present invention is simple, efficient and timely, and does not require double-sided glue exposure.

[0039] The back overlay verification method used in the present invention is to expose and develop the transparent film in the first layer, align the back side with the transparent film, and then continue to expose the front side. After development, the overlay error can be intuitively obtained by reading the vernier caliper on the edge of the size mark. The overlay error can be compensated in the device in real time, which is conducive to correcting the overlay error. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 A schematic diagram of backside overlay accuracy verification and overlay provided by an embodiment of the present invention;

[0041] Figure 2 It is a mark used by the present invention to verify the accuracy of back overlay. DETAILED DESCRIPTION

[0042] The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "including" or "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0043] For ease of understanding, the specific process of the embodiment of the present invention is described below. The first embodiment of the back side overlay accuracy verification and overlay error compensation method in the embodiment of the present invention includes:

[0044] A back side overlay accuracy verification and overlay error compensation method comprises the following steps:

[0045] Making a first set of engraved marks and first scale marks around the first set of engraved marks on the front side of the transparent sheet;

[0046] Using a backside microscope to capture and save the mask alignment mark, wherein the mask alignment mark consists of a second set of engraved marks and a second scale around the second set of engraved marks;

[0047] Use a back-side microscope to align the first scale and the second scale on the front side of the transparent film, and after alignment, expose and develop the newly made marks;

[0048] The first scale and the second scale on the newly made mark are read through an optical microscope, and the overlay accuracy is obtained through the degree of alignment between the first scale and the second scale.

[0049] The first scales are 4 groups of scales surrounding the first set of engraved marks, which are respectively located directly above, directly below, directly left and directly right of the first set of engraved marks. The second scales are 4 groups of scales surrounding the second set of engraved marks, which are respectively located directly above, directly below, directly left and directly right of the second set of engraved marks. The scales directly above and directly below are used to read the horizontal overlay deviation, and the scales directly left and directly right are used to read the vertical overlay deviation.

[0050] In the first scale and the second scale, the interval between each scale is 0.01-2 μm.

[0051] The two new marks are made on the left and right sides of the transparent sheet at the same time to obtain the overlay error values ​​(Lx, Ly), (Rx, Ry) for compensating the overlay error. The compensation algorithm is:

[0052] δx=(Lx+Rx) / 2

[0053] δy=(Ly+Ry) / 2

[0054] δθ=arctan((Ry-Ly) / d)

[0055] Among them, δx and δy are the lateral overlay deviation and the longitudinal overlay deviation respectively, and δθ is the overlay deviation angle.

[0056] Specifically, Figure 1 , expose the first layer in the automatic first mask mode, without post-baking and developing, and use the same standard test board with different size marks to perform overlay test. The size marks can be aligned on the front side of the sample Side A. The specific process is as follows:

[0057] Step 1: Make an alignment mark (vernier caliper) on Side A of the front side and align the front side with the first layer for exposure.

[0058] Step 2: First use a back-side microscope to capture and save the alignment marks of the mask.

[0059] Step 3: Load the sample with Side A facing upwards, and use a back-side microscope to align the alignment mark (vernier caliper) on the front side A of the film with the alignment mark of the mask template that has been captured and saved. After alignment, expose and develop the newly made mark (vernier caliper).

[0060] Step 4: Use an optical microscope to read the vernier caliper reading of Side A, i.e. the back alignment accuracy. A circle of vernier scales is specially designed around the overlay marks of different sizes for reading the overlay accuracy. Using the principle of vernier calipers, the minimum readable accuracy is 0.2μm.

[0061] After alignment and development, the vernier scale seen under an ordinary microscope, such as Figure 2As shown, the method of reading the vernier caliper is consistent with that of aligning the scale line indicated by the blue arrow, so according to the reading here: the overlay deviation is -1.0μm in the X direction (the direction is based on the mask-wafer), and +1.8μm in the Y direction (one grid is 0.2μm).

[0062] The two overlay error values ​​(Lx, Ly) and (Rx, Ry) are read on the left and right sides respectively and input into the offset item. The rotation and translation are automatically calculated by the algorithm to compensate the overlay error.

[0063] The compensation algorithm is δx=(Lx+Rx) / 2; δy=(Ly+Ry) / 2; δθ=arctan((Ry-Ly) / d).

[0064] As a preferred technical solution, the scale on the newly made mark adopts the intelligent recognition step:

[0065] From left to right and from top to bottom, identify the four groups of scales arranged vertically, obtain the coordinates of the midpoints of the scale tips, and arrange them in order to obtain the first, second, third, and fourth horizontal coordinate sets;

[0066] The difference between the ordinates of any two sets of coordinates in the abscissa set;

[0067] The scale with the smallest difference is taken as the lateral overlay error value;

[0068] From top to bottom and from left to right, identify the four groups of scales arranged horizontally, obtain the coordinates of the midpoints of the scale tips, and arrange them in order to obtain the first, second, third, and fourth vertical coordinate sets;

[0069] Calculate the difference between the horizontal coordinates of any two sets of vertical coordinates;

[0070] The scale with the smallest difference is taken as the longitudinal overlay error value.

[0071] The intelligent identification step also includes a correction step:

[0072] Calculate the proportion of white pixels in the quadrilateral formed by the first and second horizontal coordinate sets, the third and fourth horizontal coordinate sets, the first and second vertical coordinate sets, and the third and fourth vertical coordinate sets, respectively, to obtain a first horizontal proportion, a second horizontal proportion, a first vertical proportion, and a second vertical proportion;

[0073] Correcting the longitudinal overlay error value according to the first horizontal ratio and the second horizontal ratio;

[0074] The lateral overlay error value is corrected according to the first longitudinal ratio and the second longitudinal ratio.

[0075] The solution of the present invention not only relies on the difference in coordinates to calculate the error, but also further corrects the error by analyzing the proportion of white pixels in the scale area. By calculating the proportion of white pixels in the quadrilateral, the solution introduces an intelligent correction method based on image information. By separately calculating the proportion of white pixels in the area formed by the horizontal and vertical coordinates, this method takes into account the image characteristics of the scale area, thereby providing more accurate information for error compensation. Linking the horizontal proportion with the vertical error, and the vertical proportion with the horizontal error, more accurate error correction is achieved. This correction mechanism based on proportion differences can dynamically adjust the overlay error value to make it more in line with the actual situation.

[0076] By calculating the proportion of white pixels within the quadrilateral formed by the first and last coordinates, the scheme combines the regional information of the scale image with the error correction. This multi-dimensional analysis not only considers the coordinate points, but also combines the pixel information of the image, making the error compensation more comprehensive. This meticulous correction strategy effectively improves the overlay accuracy.

[0077] In order to deal with the situation of large ratio difference, it is recommended to introduce a cubic correction term, which can capture more complex nonlinear changes and design a high-order correction term combined with the ratio difference for further accurate compensation. The correction algorithm adopts the following formula:

[0078]

[0079] Wherein δx and δy are the lateral overlay error and the longitudinal overlay error, Ph1 and Ph2 are the first lateral ratio and the second lateral ratio, Pv1 and Pv2 are the first longitudinal ratio and the second longitudinal ratio, α and β are empirical coefficients, which control the amplitude of linear and high-order correction respectively.

[0080] The high-order correction formula can flexibly handle errors of different degrees by introducing a combination of linear and nonlinear terms. The introduction of the cubic term ensures that the system can provide more effective corrections when the proportion difference is large, solving the problem that simple linear correction cannot fully compensate for large errors. The method of this embodiment is very suitable for the scenario of precision overlay error compensation, especially in fields with high precision requirements such as semiconductor manufacturing. The accuracy of error compensation can be further improved.

[0081] In the case of small errors: When both the error and the proportional difference are small, the results of linear correction and high-order correction are very close, or even negligible, and the error correction effects are almost the same.

[0082] In the case of medium error: As the error increases, especially when the ratio difference is large (such as 0.9-0.4), the high-order correction term begins to show obvious effect, which can compensate 0.171μm more than the linear correction.

[0083] In the case of large errors: In the case of large errors and large proportional differences, high-order correction can provide greater compensation. For example, in the case of δx = 3.0 μm and a proportional difference of 0.9-0.4, high-order correction compensates 0.342 μm more than linear correction.

[0084] The above describes the back side overlay accuracy verification and overlay error compensation method in the embodiment of the present invention. The following describes the back side overlay accuracy verification and overlay error compensation device in the embodiment of the present invention. The first embodiment of the back side overlay accuracy verification and overlay error compensation device in the embodiment of the present invention includes:

[0085] A first engraving unit is used to make a first set of engraved marks and first scale marks around the first set of engraved marks on the front side of the transparent sheet;

[0086] an alignment unit, using a backside microscope to capture and save a mask alignment mark, wherein the mask alignment mark consists of a second set of engraved marks and a second scale around the second set of engraved marks;

[0087] The second engraving unit uses a back microscope to align the first scale and the second scale on the front side of the transparent sheet, and after alignment, exposes and develops the newly made marks;

[0088] The overlay accuracy reading unit reads the first scale and the second scale on the newly made mark through an optical microscope, and obtains the overlay accuracy through the alignment degree of the first scale and the second scale.

[0089] Scale recognition unit:

[0090] From left to right and from top to bottom, identify the four groups of scales arranged vertically, obtain the coordinates of the midpoints of the scale tips, and arrange them in order to obtain the first, second, third, and fourth horizontal coordinate sets;

[0091] The difference between the ordinates of any two sets of coordinates in the abscissa set;

[0092] The scale with the smallest difference is taken as the lateral overlay error value;

[0093] From top to bottom and from left to right, identify the four groups of scales arranged horizontally, obtain the coordinates of the midpoints of the scale tips, and arrange them in order to obtain the first, second, third, and fourth vertical coordinate sets;

[0094] Calculate the difference between the horizontal coordinates of any two sets of vertical coordinates;

[0095] The scale with the smallest difference is taken as the longitudinal overlay error value.

[0096] Correction unit:

[0097] Calculate the proportion of white pixels in the quadrilateral formed by the first and second horizontal coordinate sets, the third and fourth horizontal coordinate sets, the first and second vertical coordinate sets, and the third and fourth vertical coordinate sets, respectively, to obtain a first horizontal proportion, a second horizontal proportion, a first vertical proportion, and a second vertical proportion;

[0098] Correcting the longitudinal overlay error value according to the first horizontal ratio and the second horizontal ratio;

[0099] The lateral overlay error value is corrected according to the first longitudinal ratio and the second longitudinal ratio.

[0100] The correction algorithm uses the following formula:

[0101]

[0102] Wherein δx and δy are the lateral overlay error and the longitudinal overlay error, Ph1 and Ph2 are the first lateral ratio and the second lateral ratio, Pv1 and Pv2 are the first longitudinal ratio and the second longitudinal ratio, α and β are empirical coefficients, which control the amplitude of linear and high-order correction respectively.

[0103] An embodiment of the present invention provides an electronic device, which can produce different

[0104] There are significant differences between them, and they may include one or more central processing units,

[0105] CPU) (e.g., one or more processors) and memory, one or more storage applications

[0106] A storage medium for a program or data (e.g., one or more mass storage devices). The memory and storage medium may be short-term storage or permanent storage. The program stored in the storage medium may include one or more modules (not shown), each of which may include a series of instruction operations in the electronic device. Furthermore, the processor may be configured to communicate with the storage medium and execute a series of instruction operations in the storage medium on the electronic device.

[0107] The electronic device may also include one or more power supplies, one or more wired or wireless network interfaces, one or more input and output interfaces, and / or one or more operating systems, such as Windows Serve, Mac OS X, Unix, Linux, FreeBSD, etc.

[0108] The structure of an electronic device provided by an embodiment of the present invention may have relatively large differences due to different configurations or performances, and may include one or more processors (central processing units, CPU) (for example, one or more processors) and memories, and one or more storage media for storing applications or data (for example, one or more mass storage devices). Among them, the memories and storage media may be short-term storage or permanent storage. The program stored in the storage medium may include one or more modules (not shown in the figure), and each module may include a series of instruction operations in the electronic device. Furthermore, the processor may be configured to communicate with the storage medium and execute a series of instruction operations in the storage medium on the electronic device.

[0109] The electronic device may also include one or more power supplies, one or more wired or wireless network interfaces, one or more input and output interfaces, and / or one or more operating systems, such as Windows Server, Mac OS X, Unix, Linux, FreeBSD, etc. Those skilled in the art will appreciate that the electronic device structure does not constitute a limitation on the electronic device, and may include more or less components than the aforementioned, or combine certain components, or arrange the components differently.

[0110] The present invention also provides a computer-readable storage medium, which may be a non-volatile computer-readable storage medium or a volatile computer-readable storage medium. Instructions are stored in the computer-readable storage medium. When the instructions are executed on a computer, the computer executes the steps of the back-side overlay accuracy verification and overlay error compensation method.

[0111] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the above-described system, device, or unit can refer to the corresponding process in the aforementioned method embodiment and will not be repeated here.

[0112] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk and other media that can store program codes.

[0113] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A backside overlay accuracy verification and overlay error compensation method, characterized in that: The following steps are involved: Making a first set of engraved marks and first scale marks around the first set of engraved marks on the front side of the transparent sheet; Using a backside microscope to capture and save the mask alignment mark, wherein the mask alignment mark consists of a second set of engraved marks and a second scale around the second set of engraved marks; Use a back-side microscope to align the first scale and the second scale on the front side of the transparent film, and after alignment, expose and develop the newly made marks; Reading the first scale and the second scale on the newly made mark through an optical microscope, and obtaining the overlay accuracy through the alignment degree of the first scale and the second scale; The scale on the newly made mark adopts an intelligent recognition method: From left to right and from top to bottom, identify the four groups of scales arranged vertically, obtain the coordinates of the midpoints of the scale tips, and arrange them in order to obtain the first, second, third, and fourth horizontal coordinate sets; Calculate the difference between the ordinates of any two sets of coordinates in the abscissa set; The scale with the smallest difference is taken as the lateral overlay error value; From top to bottom and from left to right, identify the four groups of scales arranged horizontally, obtain the coordinates of the midpoints of the scale tips, and arrange them in order to obtain the first, second, third, and fourth vertical coordinate sets; Calculate the difference between the horizontal coordinates of any two sets of vertical coordinates; The scale with the smallest difference is taken as the longitudinal overlay error value; The intelligent recognition method also includes a correction step: Calculate the proportion of white pixels in the quadrilateral formed by the first and second horizontal coordinate sets, the third and fourth horizontal coordinate sets, the first and second vertical coordinate sets, and the third and fourth vertical coordinate sets, respectively, to obtain a first horizontal proportion, a second horizontal proportion, a first vertical proportion, and a second vertical proportion; Correcting the longitudinal overlay error value according to the first horizontal ratio and the second horizontal ratio; The lateral overlay error value is corrected according to the first longitudinal ratio and the second longitudinal ratio.

2. A backside overlay accuracy verification and overlay error compensation method according to claim 1, characterized in that: The first scales are 4 groups of scales surrounding the first set of engraved marks, which are respectively located directly above, directly below, directly left and directly right of the first set of engraved marks. The second scales are 4 groups of scales surrounding the second set of engraved marks, which are respectively located directly above, directly below, directly left and directly right of the second set of engraved marks. The scales directly above and directly below are used to read the horizontal overlay deviation, and the scales directly left and directly right are used to read the vertical overlay deviation.

3. A back side overlay accuracy verification and overlay error compensation method according to claim 2, characterized in that: In the first scale and the second scale, the interval between each scale is 0.01-2 μm.

4. A backside overlay accuracy verification and overlay error compensation method according to claim 1, characterized in that: The two new marks are made on the left and right sides of the transparent sheet at the same time to obtain the overlay error values ​​(Lx, Ly), (Rx, Ry) for compensating the overlay error. The compensation algorithm is: δx=(Lx+Rx) / 2 δy=(Ly+Ry) / 2 δθ=arctan((Ry-Ly) / d) Among them, δx and δy are the lateral overlay deviation and the longitudinal overlay deviation respectively, and δθ is the overlay deviation angle.

5. The method for verifying backside overlay accuracy and compensating overlay error according to claim 1, characterized in that: The correction algorithm uses the following formula: Wherein δx and δy are the lateral overlay error and the longitudinal overlay error, Ph1 and Ph2 are the first lateral ratio and the second lateral ratio, Pv1 and Pv2 are the first longitudinal ratio and the second longitudinal ratio, α and β are empirical coefficients, which control the amplitude of linear and high-order correction respectively.

6. A back side overlay accuracy verification and overlay error compensation system for executing the back side overlay accuracy verification and overlay error compensation method as claimed in any one of claims 1 to 5, characterized in that: The back side overlay accuracy verification and overlay error compensation system comprises: A first engraving unit is used to make a first set of engraved marks and first scale marks around the first set of engraved marks on the front side of the transparent sheet; an alignment unit, using a backside microscope to capture and save a mask alignment mark, wherein the mask alignment mark consists of a second set of engraved marks and a second scale around the second set of engraved marks; The second engraving unit uses a back microscope to align the first scale and the second scale on the front side of the transparent sheet, and after alignment, exposes and develops the newly made marks; An overlay accuracy reading unit is used to read the first scale and the second scale on the newly made mark through an optical microscope, and obtain the overlay accuracy through the alignment degree of the first scale and the second scale; Scale recognition unit and correction unit.

7. An electronic device, comprising a memory and at least one processor, wherein instructions are stored in the memory; The at least one processor calls the instructions in the memory so that the electronic device executes each step of the back side overlay accuracy verification and overlay error compensation method as described in any one of claims 1-5.

8. A computer-readable storage medium having instructions stored thereon, characterized in that: When the instructions are executed by the processor, the various steps of the back side overlay accuracy verification and overlay error compensation method as described in any one of claims 1 to 5 are implemented.

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