TWI855411B - Method and system for measuring the depth of a damaged layer on a wafer surface - Google Patents

Abstract

The present invention relates to a method and system for measuring the depth of a damaged layer on a wafer surface. The method comprises: step 101: repeatedly performing a pull-up etching operation on a wafer to be tested, wherein the wafer is immersed in an etching solution for a predetermined time and then pulled out of the etching solution, so that a step shape having a series of step surfaces is formed on the surface of the wafer by etching with the etching solution; step 102: The series of terraces are sequentially inspected for damage until no damage is detected; step 103: determining the depth of the surface damage layer of the wafer according to the number of pull-up etching operations performed when no damage is detected and the thickness of the wafer etched away each time the wafer is immersed in the etching solution, wherein the thickness is calculated based on the etching rate of the etching solution and the specified time.

Description

Method and system for measuring the depth of a damaged layer on a wafer surface

The present invention belongs to the field of wafer processing and manufacturing technology, and specifically, relates to a method and system for measuring the depth of a damaged layer on a wafer surface.

In the manufacturing process from pulled single crystal silicon rods to wafers, multiple processes such as rolling, slicing, grinding, etching, and polishing are required. In the mechanical processing processes such as rolling, slicing, and grinding, mechanical damage will inevitably be introduced on the surface of the wafer. The surface mechanical damage destroys the original single crystal layer and seriously affects the quality of the silicon wafer. Therefore, it is necessary to remove the damaged layer through processes such as etching and polishing in the subsequent processing. When removing the mechanically damaged layer on the surface of the wafer, it is necessary to be able to accurately measure the depth of the damaged layer in order to set the specific removal amount related to the removal operation accordingly.

Among the related technologies, damage layer depth measurement technology is divided into direct measurement and indirect measurement. Direct measurement refers to directly observing the damage on the chip cross section, but because the damage is shallow, it is not easy to observe directly with a microscope. Usually, the chip is cut and then a scanning electron microscope (SEM)/transmission electron microscope (TEM) and other high-precision equipment are used to observe the cross section, but the equipment cost of this method is high and the sample preparation is complicated.

Angle polishing is an indirect measurement method commonly used in laboratories. In this method, the vertical damage layer is polished into a smooth bevel to magnify the damage layer to match the measurement accuracy of the microscope. The polished bevel will be etched to further magnify the damage and measured with a microscope, and then converted to the actual damage depth through geometry.

However, the angle polishing method has high requirements for sample processing and measurement. First, the method requires the wafer to be split and small pieces to be obtained before processing, and the etching of the small pieces after polishing requires the design of separate fixtures and troughs; secondly, the sample processing requires the small piece to be glued to a bevel with a known angle, and then the bevel is glued to the polishing plate. The two glues lead to poor stability; moreover, when the sample is angle polished, it is necessary to avoid introducing new damage. It is best to grind the bevel to a smooth surface. The smoothness of the bevel directly affects the resolution of the microscope; finally, when measuring the bevel, the interface between the damaged layer and the undamaged layer is judged by the naked eye, which makes the measurement result greatly affected by personnel.

This section provides a general summary of the invention, and is not a comprehensive disclosure of its full scope or all of its features.

An object of the present invention is to provide a method for measuring the depth of a damaged layer on a wafer surface using a complete wafer.

Another object of the present invention is to provide a method for measuring the depth of the damage layer on the wafer surface, which can directly measure the depth of the damage layer on the wafer surface without reverse deduction through geometric relationships.

Another object of the present invention is to provide a method for measuring the depth of a damaged layer on a wafer surface which can avoid judgment errors introduced by naked eye observation.

In order to achieve one or more of the above purposes, according to one aspect of the present invention, a method for measuring the depth of a damaged layer on a wafer surface is provided, which comprises: Step 101: repeatedly performing a pull-up etching operation on a wafer to be tested, wherein the wafer is immersed in an etching solution for a specified time and pulled out of the etching solution for multiple times, so that a step shape having a series of terraces is formed on the surface of the wafer by etching with the etching solution; Step 102: sequentially performing damage detection on the series of terraces until no damage is detected; Step 103: Determine the depth of the surface damage layer of the wafer based on the number of pull-up etching operations that have been performed when no damage is detected and the thickness of the wafer etched away each time it is immersed in the etching solution, wherein the thickness is calculated based on the etching rate of the etching solution and the specified time.

In the above method for measuring the depth of the damage layer on the wafer surface, in step 102, if the last step in the series of steps is still detected to have damage, steps 101 and 102 may be repeated.

In the above method for measuring the depth of the damaged layer on the wafer surface, the prescribed time for each immersion of the wafer in the etching solution may be equal.

In the above method for measuring the depth of the damage layer on the wafer surface, sequentially performing damage detection on the series of terraces may include sequentially performing roughness detection on the series of terraces, and no damage is detected, which is determined by detecting that the roughness tends to be constant.

In the above method for measuring the depth of the damage layer on the wafer surface, sequentially performing damage detection on the series of steps may include sequentially performing X-ray diffraction detection on the series of steps, and no damage is detected by detecting that the half-height width of the diffraction front tends to be constant.

In the above method for measuring the depth of the damaged layer on the wafer surface, the etching solution may be a Bright etching solution prepared by mixing nitric acid, hydrofluoric acid, acetic acid, and distilled water in a volume ratio of 4:1:2:3.

In the above method for measuring the depth of the damaged layer on the wafer surface, the specified time can be set to 5s to 10s.

In the above method for measuring the depth of the damaged layer on the wafer surface, the corrosion rate can be determined by the following steps: Step 1: measuring the initial thickness of the test wafer; Step 2: immersing the test wafer in the etching solution for a specific time and taking it out; Step 3: measuring the remaining thickness of the test wafer after step 2; and Step 4: calculating the corrosion rate based on the difference between the initial thickness and the remaining thickness and the specific time.

According to another aspect of the present invention, a system for measuring the depth of a damaged layer on a wafer surface is provided, comprising: A pulling unit, which is used to repeatedly perform a pulling etching operation on a wafer to be tested, immersing the wafer in an etching solution for a specified time and pulling the wafer out of the etching solution, so that a step shape having a series of step surfaces is formed on the surface of the wafer by etching with the etching solution; A detection unit, which is used to perform damage detection on the series of step surfaces in sequence until no damage is detected; and The calculation acquisition unit is used to determine the depth of the surface damage layer of the wafer according to the number of pull-up etching operations that have been performed when no damage is detected and the thickness of the wafer etched and peeled off each time the wafer is immersed in the etching solution, wherein the thickness is calculated by the calculation acquisition unit according to the etching rate of the etching solution and the specified time.

The system for measuring the depth of the damaged layer on the surface of the wafer may further include a repeating unit for causing the pulling unit and the detecting unit to repeat the operation when the detecting unit detects that the last step in the series of steps still has damage.

In the embodiment of the present invention, by directly using the whole wafer to measure the depth of the damaged layer, the etcher and material basket of the laboratory, which are general testing equipment, can be directly applied, avoiding the need for a specially designed fixture and trough when the wafer is split into small pieces for measurement, and also avoiding the problem of poor stability caused by bonding during angle polishing and the possible introduction of new damage on the inclined surface due to polishing, thereby affecting the measurement results. In addition, by horizontally decomposing the vertical damage in this method to determine the change of the damage degree with the depth, the depth of the damaged layer itself can be tested without the need for reverse deduction through geometric relationships. In addition, in the present method, the damaged surface, i.e., the terrace, at each depth is obtained by peeling layer by layer, and roughness detection/X-ray diffraction detection, for example, is used to clearly determine whether the terrace is damaged, thereby avoiding human judgment errors that may be introduced by naked eye observation.

The above features and advantages as well as other features and advantages of the present invention will become more apparent through the following detailed description of exemplary embodiments of the present invention in conjunction with the accompanying drawings.

In order to help you understand the technical features, contents and advantages of the present invention and the effects it can achieve, the present invention is described in detail as follows with the accompanying drawings and appendices in the form of embodiments. The drawings used therein are only for illustration and auxiliary description, and may not be the true proportions and precise configurations after the implementation of the present invention. Therefore, the proportions and configurations of the attached drawings should not be interpreted to limit the scope of application of the present invention in actual implementation.

In the description of the embodiments of the present invention, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

The present invention is described in detail below with reference to the accompanying drawings by means of exemplary embodiments. It should be noted that the following detailed description of the present invention is only for illustrative purposes and is by no means a limitation of the present invention.

The commonly used methods for measuring the depth of the wafer damage layer include angle polishing, which requires the wafer to be split into small samples. The angle polishing method generally includes the following steps: Splitting the wafer into multiple smaller samples; Using, for example, resin glue to bond the sample to a bevel of known angle, and then bonding the bevel to a polishing disk; Polishing the sample cross section into a bevel of known angle so that the damage layer on the wafer surface can be exposed on the bevel of known angle; Using a special fixture to clamp the sample and put it into the etching solution for etching, so that the damage layer on the bevel of known angle can be further magnified and displayed; and

The boundary line or interface of the bonded sample is observed under a microscope. The length of the crack at the boundary line and the number and distribution of the etch pits are used to measure the length of the damage on the slope of the known angle, and the depth of the damaged layer is calculated by the sine value of the length and the known angle.

However, it can be seen from the above steps that this method requires wafer splitting to obtain smaller samples, and a separate fixture and trough need to be designed when etching the polished small pieces; the small pieces need to be bonded to a bevel with a known angle, and the bevel needs to be bonded to the polishing plate, and the two bondings result in poor stability; when the sample is angle-polished, new damage should be avoided, and the bevel is preferably ground to a smooth surface, and the smoothness of the bevel directly affects the resolution of the microscope; moreover, when measuring the bevel, the interface between the damaged layer and the undamaged layer is judged by the naked eye, which makes the measurement result greatly affected by personnel.

To solve the above problem, the present invention measures the depth of the damaged layer by laterally decomposing the damage in the direction perpendicular to the wafer surface and judging the change of the damage degree as the depth changes. Specifically, referring to FIG. 1 , the embodiment of the present invention provides a method for measuring the depth of a damaged layer on a wafer surface, the method comprising: Step 101: repeatedly performing a pull-up etching operation on a wafer 100 to be tested, immersing the wafer 100 in an etching solution for a specified time and pulling the wafer 100 out of the etching solution, so that a terrace shape having a series of terraces is formed on the surface of the wafer 100 by etching with the etching solution; Step 102: sequentially performing damage detection on the series of terraces until no damage is detected; Step 103: Determine the depth of the surface damage layer of the wafer 100 according to the number of pull-up etching operations that have been performed when no damage is detected and the thickness of the wafer 100 etched away each time it is immersed in the etching solution, wherein the thickness is calculated based on the etching rate of the etching solution and the specified time.

In this method, the depth of the damaged layer can be directly measured for the whole wafer. The whole wafer can be directly applied to the laboratory's general testing equipment such as the etcher and the material basket. The pull-up etching operation can be realized through the program of the etcher robot arm. However, the measurement after the wafer is split into small pieces requires the design of a special fixture and trough for etching the small pieces. In addition, since there is no need to split the wafer into small pieces, there is no problem of poor stability caused by two bondings when performing angle polishing on the small pieces, and there is no problem of introducing new damage on the bevel due to angle polishing, thereby affecting the measurement results. This saves processes, reduces costs, and improves the accuracy of the measurement results.

Referring to FIG. 2 and FIG. 3 , for step 101, the pull-up etching operation is an operation of immersing the wafer 100 in an etching solution for a predetermined time and pulling it out of the etching solution. In this operation, the etching solution etches the surface of the wafer 100, so that the surface is peeled off by a certain thickness. By repeatedly performing this pull-up etching operation, a terrace shape with a series of terraces is formed on the surface, as can be clearly seen in FIG. In this way, the damaged layer in the direction perpendicular to the wafer surface is decomposed horizontally.

After a series of terraces are formed, step 102 can be performed, i.e., damage detection is performed on these terraces in sequence. It should be noted that the damage detection is only to detect whether there is still damage at the terrace. As the etching liquid etches layer by layer, the damaged layer on the wafer surface will be etched away through continuous thickness peeling, i.e., etching is performed to a perfect layer, and correspondingly, no damage will be detected.

In this case, step 103 can be performed, that is, the number n of pull-up etching operations that have been performed when no damage is detected is counted, and the thickness ΔL of the wafer 100 etched and peeled off each time it is immersed in the etching solution is calculated based on the corrosion rate v of the etching solution and the specified time t, and finally the depth H of the surface damage layer of the wafer is calculated based on the number of times and the thickness.

In the above method, the change of damage degree with depth is determined by decomposing vertical damage horizontally. What is tested is the depth of the damaged layer itself. There is no need to reverse the geometric relationship, and the measurement result can be obtained more quickly and accurately.

It is conceivable that the prescribed time t for each immersion of the wafer in the etching solution may be equal.

The thickness ΔL can be calculated by the formula ΔL=v*t. When the specified time t of the wafer being immersed in the etching solution is equal each time, the thickness ΔL etched away from the wafer each time it is immersed in the etching solution is also equal. In this case, the depth H of the surface damage layer of the wafer can be directly calculated by the formula H=n*ΔL.

It is also conceivable that the prescribed time t for each immersion of the wafer in the etching solution may be different. For example, in the first few pull-up etching operations, t may be relatively long so that the wafer is etched away by the etching solution to a greater thickness to save operation time, while in subsequent pull-up etching operations, t may be relatively short so that the etching gradually approaches the perfect layer with a smaller amount of stripping, thereby avoiding the situation where the prescribed time t is too long and the etching reaches the perfect layer too early before t is completed, resulting in inaccurate measurement results.

In this case, the thickness ΔL etched away from the wafer each time it is immersed in the etching solution is also different. It is necessary to add these different thicknesses ΔL according to the number n of pull-up etching operations that have been performed when no damage is detected to obtain the depth H of the surface damage layer of the wafer.

It is understandable that the specified time t should not be too long, so as to avoid the etching reaching the perfect layer too early before t is completed, resulting in inaccurate measurement results. On the other hand, the specified time t should not be too short, so as to avoid too many pull-up etching operations before reaching the perfect layer, resulting in the entire process taking too long. Usually, the specified time t can be set to a few seconds.

It should be noted that the number of pull-up etching operations in step 101 can be roughly set according to the corrosion rate of the etching solution, the estimated depth of the damaged layer and the set prescribed time, so that the etching can reach a perfect layer through the set number of pull-up etching operations.

According to an embodiment of the present invention, in step 102, if the last step in the series of steps is still detected to be damaged, steps 101 and 102 may be repeated.

Specifically, when damage is still detected on the last step after the series of steps are tested for damage in sequence, step 101 needs to be repeated, i.e., the wafer is repeatedly subjected to multiple pull-up and etching operations to continue to form multiple new steps, and then step 102 is performed, i.e., the multiple new steps are tested for damage in sequence until no damage is detected. This process can be repeated until damage is still not detected on the last step.

An exemplary implementation of damage detection for a step is described in detail below with reference to FIGS. 4 to 7 .

According to an embodiment of the present invention, referring to FIG. 4 and FIG. 5 , the damage detection of the series of terraces includes sequentially performing roughness detection on the series of terraces, and no damage is detected, which is determined by detecting that the roughness tends to be constant.

Specifically, the roughness of each terrace can be detected to detect whether there is damage on the terrace. For the roughness detection process, after the wafer after multiple pull-up and etching operations is placed on the test platform, as shown in FIG4 , the roughness detector, specifically the roughness probe 11 of the roughness detector, can be moved to sequentially detect the roughness of the series of terraces of the wafer 100 supported on the supporting base 10 at a fixed position.

Alternatively, the supporting base 10 for supporting the wafer 100 may be moved so that the roughness detector at a fixed position, specifically the roughness probe 11 of the roughness detector, sequentially detects the roughness of the series of terraces on the surface of the wafer 100 .

FIG5 shows the relationship curve between each detected roughness value and the number of pull-up etching operations. As the number of pull-up etching operations increases, the terrace formed after etching and peeling gradually approaches the perfect layer, so that the roughness detected at the terrace gradually approaches the roughness of the perfect layer. When the roughness value tends to remain constant, the curve in FIG5 also changes from a continuously changing curvature to a straight line that tends to be close to a horizontal line, and it is determined that the etching has reached the perfect layer, that is, no damage is detected. At this time, the number of pull-up etching operations that have been performed is the number of pull-up etching operations that have been performed when no damage is detected.

According to another embodiment of the present invention, referring to FIG. 6 and FIG. 7 , performing damage detection on the series of terraces in sequence includes performing X-ray diffraction detection on the series of terraces in sequence, and no damage is detected by detecting that the half-height width of the diffraction front tends to be constant.

Specifically, the detection of whether there is damage at each step can be achieved by performing X-ray diffraction detection at the step. For the X-ray diffraction detection process, after placing the wafer after multiple pull-up and etching operations on the test platform, as shown in FIG6 , the support base 10 for supporting the wafer 100 can be moved so that the X-ray diffraction instrument 12 in a fixed position sequentially performs X-ray diffraction detection on the series of steps formed on the surface of the wafer 100. As shown in FIG6 , X-rays are emitted from the X-ray diffraction instrument, diffracted at the step, and then received by the X-ray diffraction instrument.

Likewise, alternatively, the X-ray diffraction device 12 may be moved to sequentially perform X-ray diffraction inspection on the series of steps of the wafer 100 supported on the support base 10 at a fixed position.

Figure 7 shows the relationship between the half-height width of each detected diffraction peak and the number of pull-etching operations. As the number of pull-etching operations increases, the terrace formed after etching and stripping gradually approaches the perfect layer, so that the diffraction peak detected at the terrace gradually approaches the diffraction peak of the perfect layer. When there is severe damage on the wafer surface, there is almost no crystal property, so the half-height width of the diffraction curve is The width is very large. As the etching continues, the half-height width of the diffraction curve of the damaged layer will gradually decrease. When the half-height width of the diffraction peak tends to be constant, the curve in Figure 7 also changes from a constantly changing curvature to a nearly horizontal straight line, and it is determined that the etching has reached a perfect layer, that is, no damage is detected. The number of pull-up etching operations that have been performed at this time is the number of pull-up etching operations that have been performed when no damage is detected.

In this method, the damaged surface, i.e., the terrace surface, at each depth is obtained by peeling layer by layer, and roughness detection/X-ray diffraction detection, for example, is used to clearly determine whether the terrace surface is damaged, thereby avoiding human judgment errors that may be introduced by naked eye observation.

It is also conceivable to use detection methods in other related technologies to detect whether there is damage on the platform step.

According to the implementation of the present invention, the etching solution can be a Bright etching solution, wherein Bright etching solution is a mixed acid including nitric acid, hydrofluoric acid and acetic acid commonly used for thinning in semiconductor enterprises. As an example, the Bright etching solution in this implementation can be a mixture of nitric acid, hydrofluoric acid, acetic acid and distilled water in a volume ratio of 4:1:2:3.

The etching solution may include acid etching solutions commonly used in wafer thinning, such as nitric acid, glacial acetic acid, and hydrofluoric acid, and alkaline etching solutions such as KOH solution. As another example, the etching solution may also be a mixed acid formed by mixing hydrofluoric acid, nitric acid, sulfuric acid, and phosphoric acid in a volume ratio of 1:6:1:2.

When using Bright etching solution made of nitric acid, hydrofluoric acid, acetic acid and distilled water in a volume ratio of 4:1:2:3, the etching rate is 6um/min, or 0.1um/s. Since the damage depth on the wafer surface is generally in the range of 5um to 20um, the time that the wafer is immersed in the etching solution each time, i.e., the specified time t, can be set to 5s to 10s.

The specified time can be set differently according to the type of wafer. For example, when the wafer is obtained after wire cutting, due to the large damage on its surface, the single specified time can be set to 10s, and the corresponding number of pull-up etching operations can be set to about 25 times; and when the wafer is obtained after fine grinding, due to the small damage on its surface, the single specified time can be set to 2s or 5s, and the corresponding number of pull-up etching operations can be set to about 10 times or 25 times respectively.

In an embodiment of the present invention, the corrosion rate of the etching solution can be determined by the following steps: Step 1: measuring the initial thickness of the test wafer; Step 2: immersing the test wafer in the etching solution for etching for a specific time and taking it out; Step 3: measuring the remaining thickness of the test wafer after step 2; and Step 4: calculating the corrosion rate based on the difference between the initial thickness and the remaining thickness and the specific time.

Specifically, for example, a whole wafer can be selected as a test wafer, and the initial thickness d0 of the test wafer is first measured, and the wafer is put into the etching solution for etching time t and then taken out as a whole, and then the thickness at this time, i.e., the retained thickness, is measured as d1, and thus, the corrosion rate can be calculated according to v=(d1-d0)/t. For example, for the above-mentioned Bright etching solution composed of nitric acid, hydrofluoric acid, acetic acid, and distilled water in a volume ratio of 4:1:2:3, after testing and calculation, its corrosion rate is 6um/min.

According to another aspect of the present invention, a system for measuring the depth of a damaged layer on a wafer surface is provided, which includes: A pulling unit, which is used to repeatedly perform a pulling etching operation on a wafer to be tested, immersing the wafer in an etching solution for a specified time and pulling it out of the etching solution for multiple times, so that a step shape having a series of step surfaces is formed on the surface of the wafer by etching with the etching solution; A detection unit, which is used to perform damage detection on the series of step surfaces in sequence until no damage is detected; and The calculation acquisition unit is used to determine the depth of the surface damage layer of the wafer according to the number of pull-up etching operations that have been performed when no damage is detected and the thickness of the wafer etched and peeled off each time the wafer is immersed in the etching solution, wherein the thickness is calculated by the calculation acquisition unit according to the etching rate of the etching solution and the specified time.

According to an embodiment of the present invention, the system for measuring the depth of the damaged layer on the wafer surface may further include a repeating unit, which is used to cause the pulling unit and the detection unit to repeatedly operate when the detection unit detects that the last step in the series of steps still has damage.

According to an embodiment of the present invention, the detection unit may include a roughness detector or an X-ray diffractometer.

According to an embodiment of the present invention, the lifting unit may include a basket for placing the wafer to be tested and a robot arm for lifting the basket.

The above are only preferred embodiments of the present invention and are not intended to limit the scope of implementation of the present invention. If the present invention is modified or replaced by something equivalent without departing from the spirit and scope of the present invention, it should be included in the protection scope of the patent application of the present invention.

100: Wafer 10: Carrier base 11: Roughness probe 12: X-ray diffractometer 101-103: Steps

FIG1 is a schematic flow chart of a method for measuring the depth of a wafer surface damage layer according to an embodiment of the present invention; FIG2 schematically shows in a front view a wafer obtained by performing multiple pull-up and etching operations on a wafer to be tested using the method for measuring the depth of a wafer surface damage layer according to an embodiment of the present invention; FIG3 schematically shows in a side cross-sectional view a series of terraces of the wafer in FIG2; FIG4 schematically shows the operation process of using roughness detection to realize damage detection of terraces; FIG5 schematically shows in a curve diagram the relationship between the detected roughness value and the number of pull-ups; FIG6 schematically shows the operation process of using X-ray diffraction detection to realize damage detection of terraces; Figure 7 schematically shows the relationship between the half-width of the detected diffraction peak and the number of pull-ups in a curve diagram.

101-103: Steps

Claims (6)

A method for measuring the depth of a damaged layer on a wafer surface comprises: step 101: repeatedly performing a pull-up etching operation on a wafer to be tested, wherein the wafer is immersed in an etching solution for a predetermined time and then pulled up from the etching solution, so that a step shape having a series of terraces is formed on the surface of the wafer by etching with the etching solution; step 102: sequentially performing damage detection on the series of terraces until no damage is detected; step 103: determining the depth of a damaged layer on a wafer surface according to the number of pull-up etching operations performed when no damage is detected and the number of steps of the wafer after each immersion in the etching solution; The depth of the surface damage layer of the wafer is determined by the thickness of the etching stripped off in the etching solution, wherein the thickness is calculated based on the etching rate of the etching solution and the specified time; wherein, in the step 102, if the last terrace in the series of terraces is still detected to have damage, the steps 101 and 102 are repeated; the etching solution is a Bright etching solution composed of nitric acid, hydrofluoric acid, acetic acid, and distilled water in a volume ratio of 4:1:2:3; the specified time is set to 5s to 10s. A method for measuring the depth of a damaged layer on a wafer surface as described in claim 1, wherein the prescribed time for each immersion of the wafer in the etching solution is equal. A method for measuring the depth of a damage layer on a wafer surface as described in claim 1, wherein the damage detection of the series of terraces in sequence includes the roughness detection of the series of terraces in sequence, and the failure to detect damage is determined by detecting that the roughness tends to be constant. A method for measuring the depth of a damage layer on a wafer surface as described in claim 1, wherein the damage detection of the series of terraces in sequence includes performing X-ray diffraction detection on the series of terraces in sequence, and the undetected damage is determined by detecting that the half-height width of the diffraction front tends to be constant. A method for measuring the depth of a damaged layer on a wafer surface as described in claim 1, wherein the corrosion rate is determined by the following steps: step 1: measuring the initial thickness of a test wafer; step 2: immersing the test wafer in the etching solution for a specific time and then taking it out; step 3: measuring the remaining thickness of the test wafer after step 2; and step 4: calculating the corrosion rate based on the difference between the initial thickness and the remaining thickness and the specific time. A system for measuring the depth of a damaged layer on a wafer surface comprises: a pulling unit, which is used to repeatedly perform a pull-up etching operation on a wafer to be tested, immersing the wafer in an etching solution for a specified time and pulling the wafer out of the etching solution, so that a step shape having a series of terraces is formed on the surface of the wafer by etching with the etching solution; a detection unit, which is used to perform damage detection on the series of terraces in sequence until no damage is detected; and a calculation acquisition unit, which is used to calculate the depth of a damaged layer on a wafer surface according to the number of pull-up etching operations that have been performed when no damage is detected and the number of steps of the wafer during each immersion in the etching solution. The depth of the surface damage layer of the wafer is determined by the thickness of the etched and peeled layer, wherein the thickness is calculated by the calculation unit according to the corrosion rate of the etching solution and the specified time; Wherein, a repeating unit is also included, which is used to make the pulling unit and the detection unit repeat the operation when the detection unit detects that the last step in the series of steps still has damage; the etching solution is a Bright etching solution mixed with nitric acid, hydrofluoric acid, acetic acid, and distilled water in a volume ratio of 4:1:2:3; the specified time is set to 5s to 10s.

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