Method and system for detecting pressure parameters of grinding head

Abstract

This invention provides a method and system for detecting the pressure parameters of a grinding head. The method includes: providing a grinding head to be tested; setting a usage mode for the grinding head to be tested, and setting a first preset value for the pressure parameters of the grinding head to be tested in the usage mode based on the usage mode and a pre-established database; placing a thin-film sensor on the grinding head to be tested, and applying pressure to the thin-film sensor using the grinding head to be tested in the usage mode, so that the thin-film sensor detects a first actual pressure parameter of the grinding head to be tested, and verifying whether the difference between the first actual pressure parameter and the first preset value is less than a preset value; when the difference between the first actual pressure parameter and the first preset value is less than the preset value, removing the thin-film sensor, and grinding a wafer using the grinding head to be tested in the usage mode according to the first preset value. The method can ensure the grinding effect of the wafer and improve the wafer yield.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing technology, and in particular to a method and system for detecting the pressure parameters of a grinding head. Background Technology

[0002] In semiconductor manufacturing processes, wafers are typically polished using grinding heads in chemical mechanical equipment.

[0003] In related technologies, the pressure parameters of the polishing head vary depending on the wafer (for example, the pressure parameters of the polishing head should be larger for thicker wafers and smaller for thinner wafers). Therefore, before polishing a wafer, the operator will pre-set the pressure parameters of the polishing head to a set value based on experience, and then control the polishing head to polish the wafer based on the set value.

[0004] However, in related technologies, replacing the grinding head in chemical mechanical polishing equipment will change the process parameters of the grinding head. This will cause a large error between the actual pressure parameters applied when the replaced grinding head polishes the wafer and the preset value, which will affect the polishing effect of the wafer and reduce the wafer yield. Summary of the Invention

[0005] The purpose of this invention is to provide a method and system for detecting the pressure parameters of the grinding head, so as to ensure the grinding effect of the wafer and improve the wafer yield.

[0006] This invention provides a method for detecting the pressure parameters of a grinding head, the method comprising:

[0007] Provide a grinding head to be tested;

[0008] The usage mode of the grinding head to be tested is set, and based on the usage mode and a pre-established database, the pressure parameter of the grinding head to be tested in the usage mode is set to a first set value. The database includes at least one usage mode of the grinding head and a qualified pressure parameter range of the grinding head corresponding to the usage mode of the grinding head.

[0009] A thin-film sensing sheet is placed on the grinding head to be tested, and the grinding head to be tested applies pressure to the thin-film sensing sheet according to the first set value in the usage mode, so that the thin-film sensing sheet detects the first actual pressure parameter of the grinding head to be tested, and verifies whether the difference between the first actual pressure parameter and the first set value is less than a preset value.

[0010] When the difference between the first actual pressure parameter and the first set value is less than a preset value, the thin film sensing sheet is removed, and the wafer is ground in the usage mode according to the first set value using the grinding head to be tested.

[0011] Optionally, before setting the usage mode of the grinding head to be tested, the method further includes:

[0012] Establish the database;

[0013] The database establishment method includes: Step 1, setting the usage mode of the grinding head and setting the pressure parameter of the grinding head in the usage mode as a second set value, placing a thin film sensing sheet on the grinding head, and using the grinding head to apply pressure to the thin film sensing sheet according to the second set value in the usage mode, so that the thin film sensing sheet can detect the second actual pressure parameter of the grinding head.

[0014] Step 2: Remove the thin-film sensing sheet, and use the grinding head to grind the wafer according to the second set value in the usage mode, and record whether the ground wafer meets the process requirements; if it does, the second actual pressure parameter is a qualified pressure parameter, and collect the qualified pressure parameter;

[0015] Furthermore, in the same usage mode, steps one and two are executed repeatedly to obtain multiple qualified pressure parameters, and the maximum and minimum values ​​are determined among the multiple qualified pressure parameters to form a range of qualified pressure parameters;

[0016] The usage mode of the grinding head and the corresponding qualified pressure parameter range are stored in the database.

[0017] Optionally, based on the usage mode and a pre-established database, the method for setting the pressure parameter of the grinding head to be tested in the usage mode to a first set value includes:

[0018] Based on the usage mode of the grinding head to be tested, the corresponding qualified pressure parameter range is determined from the database;

[0019] The first setting value is set based on the determined corresponding qualified pressure parameter range, and the first setting value is within the corresponding qualified pressure parameter range.

[0020] Optionally, when the difference between the first actual pressure parameter and the first set value is not less than a preset value, the actual pressure parameter of the grinding head is adjusted to be less than the preset value.

[0021] Remove the thin-film sensor and use the grinding head to grind the wafer according to the first set value in the usage mode.

[0022] Optionally, the grinding head to be tested includes multiple concentric annular regions, each annular region constituting an independent grinding region. When the grinding head to be tested is used to grind the wafer, the independent grinding regions independently apply pressure to the wafer.

[0023] The usage mode of the grinding head includes the position and number of independent grinding areas for applying pressure, and the qualified pressure parameter range of the grinding head is the qualified range of the pressure parameters of the independent grinding areas for applying pressure; the first setting value of the grinding head includes the first setting value of each independent grinding area for applying pressure.

[0024] Optionally, before setting the usage mode of the grinding head to be tested, the method further includes:

[0025] Establish the database;

[0026] The database establishment method includes: Step 1, setting the usage mode of the grinding head to determine the independent grinding area in the grinding head for applying pressure, and pre-setting a second set value for the pressure parameters of each independent grinding area in the grinding head for applying pressure, and placing a thin film sensing sheet on the grinding head, applying pressure to the thin film sensing sheet using the independent grinding area for applying pressure, so as to detect the second actual pressure parameter of each independent grinding area for applying pressure using the thin film sensing sheet;

[0027] Step 2: Remove the thin-film sensing sheet and use the grinding head to grind the wafer in the usage mode, and record whether the ground wafer meets the process requirements; if it does, the second actual pressure parameter is a qualified pressure parameter, and the qualified pressure parameter is collected.

[0028] Furthermore, in the same usage mode, steps one and two are executed repeatedly to obtain multiple qualified pressure parameters corresponding to each independent grinding area used for pressure application, and the maximum and minimum values ​​are determined among the multiple qualified pressure parameters to form the range of qualified pressure parameters corresponding to each independent grinding area used for pressure application.

[0029] The usage mode of the grinding head and the qualified pressure parameter range for each independent grinding area used for applying pressure are stored in the database.

[0030] Optionally, based on the usage mode and a pre-established database, the method for setting the pressure parameter of the grinding head to be tested in the usage mode to a first set value includes:

[0031] Based on the usage mode of the grinding head to be tested, the qualified pressure parameter range for each independent grinding disc area of ​​the grinding head to be tested for applying pressure is determined from the database;

[0032] Based on the qualified pressure parameter range of each independent grinding disc area used for applying pressure, a first set value is set for the pressure parameter of each independent grinding disc area used for applying pressure in the grinding head, wherein the first set value of each independent grinding area used for applying pressure is within the corresponding qualified pressure parameter range.

[0033] Optionally, the method of applying pressure to the thin-film sensing sheet using the grinding head under test in the usage mode, so that the thin-film sensing sheet detects a first actual pressure parameter of the grinding head under test, includes:

[0034] The thin-film sensing sheet is pressured using the independent grinding areas of the grinding head to be tested, so that the first actual pressure parameter of each independent grinding area for applying pressure can be detected by the thin-film sensing sheet.

[0035] Optionally, the method for verifying whether the difference between the first actual pressure parameter and the first set value is less than a preset value includes: verifying whether the first actual pressure parameter and the first set value of each independent grinding area used for pressure application are both less than the preset value;

[0036] When the difference between the first actual pressure parameter and the first set value of each independent grinding plate area used for applying pressure is less than the preset value, the thin film sensing sheet is removed, and the wafer is ground according to the corresponding first set value using each independent grinding plate area used for applying pressure of the grinding head to be tested.

[0037] Optionally, when the difference between the first actual pressure parameter and the first set value is not less than a preset value, the method further includes: determining the faulty independent grinding area and adjusting the actual pressure parameter of the faulty independent grinding area to be less than the preset value compared with the corresponding first set value;

[0038] Remove the thin-film sensor and use the grinding head to grind the wafer according to the first set value in the usage mode.

[0039] Optionally, after detecting the first actual pressure parameter and the second actual pressure parameter using the thin-film sensing sheet, a display device is also used to display the first actual pressure parameter and the second actual pressure parameter.

[0040] Furthermore, the present invention also provides a detection system for the pressure parameters of the grinding head, the system comprising:

[0041] The grinding head to be tested;

[0042] The setting module is used to set the usage mode of the grinding head to be tested, and based on the usage mode and a pre-established database, set the pressure parameter of the grinding head to be tested in the usage mode to a first set value.

[0043] A thin-film sensing sheet is placed on the grinding head to be tested to detect the first actual pressure parameter when the grinding head to be tested is pressed according to the first set value in the usage mode;

[0044] The verification module is used to verify whether the difference between the first actual pressure parameter and the first set value is less than a preset value; when the difference between the first actual pressure parameter and the first set value is less than the preset value, the thin film sensing sheet is removed, and the wafer is ground according to the first set value in the usage mode using the grinding head to be tested.

[0045] Optionally, the system further includes a database, which includes at least one usage mode of the grinding head and a range of qualified pressure parameters for the grinding head corresponding to the usage mode of the grinding head.

[0046] Optionally, the grinding head includes multiple concentric annular regions, each annular region constituting an independent grinding region. When the grinding head grinds a wafer, the independent grinding regions independently apply pressure to the wafer. The usage mode of the grinding head includes the position and number of the independent grinding regions in the grinding head used for applying pressure, and the qualified pressure parameter range of the grinding head is the qualified range of the pressure parameters of the independent grinding regions used for applying pressure.

[0047] Optionally, the system further includes a display device connected to the thin-film sensing sheet for receiving and displaying the first actual pressure parameter detected by the thin-film sensing sheet.

[0048] Optionally, the system further includes an adjustment module, used to adjust the actual pressure parameter of the grinding head to be less than the preset value when the difference between the first actual pressure parameter and the first set value is not less than a preset value.

[0049] In summary, the grinding head inspection method and system provided by this invention, before grinding a wafer with the grinding head under test, sets the pressure parameters of the grinding head under test to a first preset value based on a database, and the first preset value is within the acceptable pressure parameter range. Then, a thin-film sensor detects the first actual pressure parameter when the grinding head under test applies pressure according to the first preset value, and determines whether the difference between the first actual pressure parameter and the first preset value is less than a preset value. If it is not less than the preset value, the actual pressure parameter of the grinding head under test is adjusted until the difference between it and the first preset value is less than the preset value. This ensures that the actual pressure parameter of the grinding head under test has a small error compared to the preset value, thereby ensuring that the actual pressure parameter is within a reasonable pressure parameter range. This avoids situations where a large error exists between the actual pressure parameter and the preset value when the grinding head grinds the wafer, leading to unreasonable actual pressure parameters and affecting the wafer grinding effect, thus improving the wafer yield. Attached Figure Description

[0050] Figure 1 This is a flowchart illustrating a method for detecting the pressure parameters of a grinding head according to an embodiment of the present invention;

[0051] Figure 2 This is a schematic diagram of a grinding head structure according to an embodiment of the present invention;

[0052] Figure 3 This is a schematic diagram of the second actual pressure parameters of the grinding head detected by the thin-film sensing sheet in one usage mode of an embodiment of the present invention;

[0053] Figure 4 This is a simulation diagram of the actual pressure application of a grinding head in mode one according to an embodiment of the present invention;

[0054] Figure 5 This is a schematic diagram of the structure of a grinding head pressure parameter detection system according to an embodiment of the present invention. Detailed Implementation

[0055] The following detailed description, in conjunction with the accompanying drawings and specific embodiments, provides a more comprehensive understanding of the method and system for detecting the pressure parameters of the grinding head proposed in this invention. The advantages and features of this invention will become clearer from the following description. It should be noted that the accompanying drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of this invention.

[0056] Figure 1 This is a flowchart illustrating a method for detecting the pressure parameters of a grinding head according to an embodiment of the present invention. Figure 1 As shown, the method may include:

[0057] Step 10a: Establish a database, which includes at least one usage mode of the grinding head and the qualified pressure parameter range of the grinding head corresponding to the usage mode of the grinding head.

[0058] In this embodiment, the grinding head may include multiple concentric annular regions, each constituting an independent grinding region. During wafer grinding, each independent grinding region corresponds to a specific area of ​​the wafer, and is used to independently apply pressure to that corresponding area. For example... Figure 2 This is a schematic diagram of a grinding head structure according to an embodiment of the present invention, as shown below. Figure 2 As shown, the grinding head may include independent grinding areas a, b, c and d. When grinding the wafer, independent grinding area a corresponds to the center area of ​​the wafer and is used to apply pressure to the center area of ​​the wafer, and independent grinding area d corresponds to the edge area of ​​the wafer and is used to apply pressure to the edge area of ​​the wafer.

[0059] Based on this, the usage mode of the grinding head includes the location and number of independent grinding zones for applying pressure. The acceptable pressure parameter range of the grinding head includes the acceptable range of pressure parameters for the independent grinding zones used for applying pressure.

[0060] Specifically, the method for establishing the database in step 10a may include:

[0061] Step 1: Set the usage mode of the grinding head and set the pressure parameter of the grinding head to a second set value. Place a thin film sensing plate on the grinding head and apply pressure to the thin film sensing plate according to the second set value in the usage mode to detect the second actual pressure parameter of the grinding head in the usage mode.

[0062] Specifically, step one may include: determining the position and number of independent grinding regions for applying pressure in the grinding head based on the thickness distribution of the wafer to be ground, in order to set the usage mode of the grinding head, and pre-setting a second set value for the pressure parameters of each independent grinding region for applying pressure in the grinding head. A thin-film sensor is placed on the grinding head, and pressure is applied to the thin-film sensor according to the corresponding second set value using the independent grinding regions for applying pressure, so as to detect the second actual pressure parameter of each independent grinding region for applying pressure using the thin-film sensor.

[0063] It's important to note that setting the grinding head's usage mode and pressure parameters is necessary because different wafers have different thickness distributions (e.g., the wafer thickness distribution could be: center region thickness > edge region thickness > other region thickness, or edge region thickness > center region thickness > other region thickness, etc.). To ensure uniform wafer thickness after grinding, the grinding head's usage mode also varies. For example, the independent grinding areas of the grinding head corresponding to areas with thinner wafer thickness may not require pressure, while the independent grinding areas of the grinding head corresponding to areas with thicker wafer thickness require pressure. Therefore, before grinding the wafer, the grinding head's usage mode must be determined, that is, the location and number of independent grinding areas for applying pressure within the grinding head must be determined. Then, a second setting value must be set for the pressure parameters of each independent grinding area to ensure that the grinding head grinds the wafer with the corresponding grinding parameters in the usage mode. Furthermore, to ensure uniform wafer thickness distribution after grinding, the pressure parameter values ​​of the independent grinding areas are positively correlated with the thickness of their corresponding wafer regions.

[0064] For example, the thickness distribution of a wafer to be ground is: edge region thickness > center region thickness > other regions thickness. Before grinding the wafer, the grinding head can be set to usage mode one. Usage mode one can be characterized by two independent grinding areas for applying pressure, located at the edge and center of the grinding head (i.e., corresponding to...). Figure 2 The independent grinding regions a and d are further defined. Since the thickness of the edge region of the wafer to be ground is greater than that of the center region, when setting the pressure parameters of the grinding head, the pressure parameter of independent grinding region a should be smaller, and the pressure parameter of independent grinding region d should be larger. For example, the pressure parameter of independent grinding region a can be set to 12 N, and the pressure parameter of independent grinding region d can be set to 18 N, so that when grinding the wafer to be ground, independent grinding regions a and d apply different pressures to the center and edge regions of the wafer to be ground, respectively, resulting in a uniform thickness distribution of the ground wafer.

[0065] Furthermore, after setting the pressure parameters of the grinding head, a second actual pressure parameter of the grinding head is detected using a thin-film sensor, and the second actual pressure parameter is displayed in the form of a coordinate graph using a display device. The horizontal axis of the coordinate graph is used to indicate each independent grinding area of ​​the grinding head, and the vertical axis of the coordinate graph is used to indicate the pressure parameter of each independent grinding area. Based on the coordinate graph, the specific value of the second actual pressure parameter of the grinding head detected by the thin-film sensor can be determined so that a database can be established based on the specific value of the second actual pressure parameter.

[0066] For example, Figure 3 This is a schematic diagram illustrating the second actual pressure parameters of the grinding head detected by the thin-film sensor in the first usage mode of this embodiment. Figure 3 It can be seen that, in the first mode of use, the second actual pressure parameter of the independent grinding area a detected by the thin film sensor is 15N, and the second actual pressure parameter of the independent grinding area d is 20N.

[0067] Furthermore, it should be noted that in this embodiment, the thin-film sensing sheet can be used to simulate the actual pressure applied by the grinding head, and a simulation diagram of the actual pressure applied by the grinding head will be displayed on the display device. This simulation diagram not only reflects the distribution of the actual pressure parameters of each independent grinding area of ​​the grinding head, but also reflects the thickness distribution of the wafer to be ground. Areas with larger actual pressure parameters correspond to thicker areas of the wafer, while areas with smaller actual pressure parameters correspond to thinner areas of the wafer.

[0068] Furthermore, Figure 4 This is a simulation diagram of the pressure applied to the grinding head in mode one of this embodiment. For example... Figure 4 As shown, the actual pressure parameter of the independent grinding area can be represented by the color depth of the independent grinding area. For example, the actual pressure parameter of the darker-colored independent grinding area is larger, and the actual pressure parameter of the lighter-colored independent grinding area is smaller. Figure 4 The actual pressure parameter of the independent grinding region d is greater than that of the independent grinding region a, which is greater than that of the independent grinding regions b and c. In other words, the thickness of the wafer region corresponding to the independent grinding region d is greater than that of the wafer region corresponding to the independent grinding region a, which is greater than that of the wafer regions corresponding to the independent grinding regions b and c.

[0069] Step 2: Remove the thin-film sensing sheet and use the grinding head to grind a wafer according to the second set value in the usage mode. Record whether the ground wafer meets the process requirements. If it does, the second actual pressure parameter is a qualified pressure parameter. Collect the qualified pressure parameter. The wafer meeting the process requirements can specifically mean that the wafer has high thickness uniformity or high wafer integrity (i.e., the wafer is not damaged).

[0070] It should be noted that, in step two, when the grinding head grinds the wafer according to the second set value in the usage mode, the pressure parameter applied to the wafer by the independent grinding area used for applying pressure is the second actual pressure parameter. This second actual pressure parameter may differ from the second set value. Therefore, it can be understood that the final grinding effect of the wafer is essentially related to the second actual pressure parameter of the grinding head. Thus, in this embodiment, when the ground wafer meets the process requirements, the second actual pressure parameter is determined as the qualified pressure parameter.

[0071] Furthermore, under the same usage mode, steps one and two are repeatedly executed for multiple wafers to obtain multiple qualified pressure parameters corresponding to the usage mode, and the maximum and minimum values ​​are determined among the multiple qualified pressure parameters to form a qualified pressure parameter range. Each of the multiple wafers has the same thickness distribution, but the thickness magnitude differs.

[0072] Specifically, the process of repeatedly executing steps one and two under the same usage mode is to obtain multiple qualified pressure parameters corresponding to each independent grinding area for applying pressure under the usage mode, so as to determine the maximum and minimum values ​​among the multiple qualified pressure parameters, thereby constituting the range of qualified pressure parameters for each independent grinding area for applying pressure under the usage mode.

[0073] For example, assuming that in the usage mode of the grinding head, the grinding head grinds a first wafer, a second wafer, a third wafer, and a fourth wafer using independent grinding areas a and d respectively, and before grinding the first wafer, the second actual pressure parameter detected for independent grinding area a is A1N, and the second actual pressure parameter detected for independent grinding area d is A2N. Before grinding the second wafer, the second actual pressure parameter detected for independent grinding area a is A3N, and the second actual pressure parameter detected for independent grinding area d is A4N. Before grinding the third wafer, the second set value detected for independent grinding area a is A5N, and the second set value detected for independent grinding area d is A6N. Before grinding the fourth wafer, the second actual pressure parameter detected for independent grinding area a is A7N, and the second actual pressure parameter detected for independent grinding area d is A8N. Furthermore, the first, second, and third wafers all meet the process requirements after grinding.

[0074] Therefore, A1N, A3N, and A5N can be determined as the reasonable pressure parameters for the independent grinding region a, and A2N, A4N, and A6N as the reasonable pressure parameters for the independent grinding region d, where A5 < A1 < A3, and A4 < A2 < A6. Thus, the acceptable pressure parameter range for the independent grinding region a is [A5, A3], and the acceptable pressure parameter range for the independent grinding region d is [A4, A6].

[0075] Finally, the usage mode of the grinding head and the qualified pressure parameter range of the grinding head are stored in the database.

[0076] Specifically, the usage mode of the grinding head, and the qualified pressure parameter range for each independent grinding area used for applying pressure under the usage mode, are stored in the database.

[0077] For example, the acceptable pressure parameter ranges for mode 1 and independent grinding area a ([A5, A3]) and independent grinding area d ([A4, A6]) can be stored in the database. For example, they can be stored in the manner shown in Table 1.

[0078] Table 1

[0079]

[0080] Step 20a: Provide a grinding head to be tested and set the usage mode of the grinding head to be tested, and based on the usage mode and a pre-established database, set the pressure parameter of the grinding head to be tested in the usage mode to a first set value.

[0081] Step 20a mainly includes:

[0082] The first step is to determine the corresponding qualified pressure parameter range from the database based on the usage mode of the grinding head to be tested.

[0083] Specifically, the usage mode of the polishing head is first determined based on the thickness distribution of the wafer to be polished. Then, based on the usage mode of the polishing head to be tested, the qualified pressure parameter range for each independent polishing wafer area used for applying pressure is determined in the database. The method for determining the usage mode of the polishing head is the same as the method in step one of step 10a, and will not be described in detail here.

[0084] For example, if the pre-set usage mode of the grinding head to be tested is usage mode one, then referring to Table 1, it can be determined that the qualified pressure parameter range for independent grinding area a is [A5, A3]; and the qualified pressure parameter range for independent grinding area d is [A4, A6].

[0085] The second step is to determine the first set value based on the determined range of qualified pressure parameters, wherein the first set value is within the corresponding range of qualified pressure parameters.

[0086] Specifically, based on the qualified pressure parameter range of each independent grinding area used for applying pressure, the pressure parameter of each independent grinding area used for applying pressure is set to a corresponding first set value, wherein the first set value of each independent grinding area used for applying pressure is within the qualified pressure parameter range of each independent grinding area used for applying pressure.

[0087] For example, the first setting value of the independent grinding area a can be 15N, and the first setting value of the independent grinding area d can be 14N, where A5 < 15 < A3, A4 < 14 < A6.

[0088] Compared to related technologies where operators set grinding head parameters based on experience before grinding wafers, this invention sets the grinding parameters of the grinding head to be tested using a database established from a large amount of experimental data. Therefore, the method of setting the pressure parameters of the grinding head before grinding wafers in this invention is more precise, ensuring the grinding effect of the wafers after grinding and improving wafer yield.

[0089] Step 30a: Place a thin-film sensing sheet on the grinding head to be tested, and apply pressure to the thin-film sensing sheet according to the first set value in the usage mode using the grinding head to be tested, so that the thin-film sensing sheet can detect the first actual pressure parameter of the grinding head to be tested, and verify whether the difference between the first actual pressure parameter and the first set value is less than a preset value.

[0090] When grinding a wafer using a grinding head under test, there may be an error between the first actual pressure parameter of the grinding head and the first set value of the grinding head, resulting in a difference between the two. If the difference is small enough, and the first set value is within the acceptable pressure parameter range, the first actual pressure parameter can also be within the acceptable pressure parameter range. This ensures that after grinding the wafer according to the first set value in the usage mode, the ground wafer meets the process requirements. However, if the difference is large, and the first set value is within the acceptable pressure parameter range, the first actual pressure parameter of the grinding head may not be within the acceptable pressure parameter range. This would cause the ground wafer to fail to meet production requirements, affecting the grinding effect and reducing the wafer yield.

[0091] Therefore, after setting the first set value of the grinding head to be tested, it is also necessary to verify whether the difference between the first actual pressure parameter of the grinding head to be tested and the first set value is less than a preset value. The preset value should be small enough, for example, the preset value can be between 1 and 2N, to ensure that the first actual pressure parameter is within the qualified pressure parameter range, thereby ensuring the grinding effect of the wafer and improving the wafer yield.

[0092] Specifically, step 30a may include: applying pressure to the thin-film sensing sheet using each independent grinding area of ​​the grinding head to be tested, so that the thin-film sensing sheet detects a first actual pressure parameter for each independent grinding area. And, verifying whether the first actual pressure parameter of each independent grinding area is less than a preset value.

[0093] For example, suppose the first actual pressure parameter detected by the thin-film sensing sheet for the independent grinding region a is 16N, the first actual pressure parameter detected for the independent grinding region d is 20N, and the preset value is 15N. Then the first preset value and the first actual pressure parameter of the independent grinding region a differ by 1N, which is less than the preset value, while the first preset value and the first actual pressure parameter of the independent grinding region d differ by 6N, which is greater than the preset value.

[0094] It should be noted that the first actual pressure parameter of the grinding head in this invention is also displayed on the display device in the form of a display diagram, so as to determine the specific value of the first actual pressure parameter based on the display result of the display device. The display method of the first actual pressure parameter is similar to that of the second actual pressure parameter; please refer to the appendix for details. Figure 3 The invention will not be described in detail here.

[0095] Step 40a: When the difference between the first actual pressure parameter and the first set value is less than a preset value, the thin film sensing sheet is removed, and the wafer is ground in the usage mode according to the first set value using the grinding head to be tested.

[0096] Specifically, when the first actual pressure parameter of each independent grinding area of ​​the grinding head under test is less than the first set value, it can be determined that the first actual pressure parameter of each independent grinding area under test is within the reasonable pressure parameter range. Then, the thin film sensing sheet is removed, and the wafer is ground according to the corresponding first set value using each independent grinding area of ​​the grinding head under test, thereby ensuring that the ground wafer meets the process requirements.

[0097] Furthermore, when the difference between the first actual pressure parameter of the grinding head to be tested and the first set value is not less than a preset value, the first actual pressure parameter of the grinding head is adjusted to be less than the preset value.

[0098] Specifically, when the first actual pressure parameter of an independent grinding area used for applying pressure in the grinding head to be tested differs from the first set value by no less than a preset value, the independent grinding area used for applying pressure is identified as a faulty independent grinding area, and the actual pressure parameter of the independent grinding area used for applying pressure is adjusted until it differs from the first set value by less than the preset value.

[0099] For example, if the difference between the first set value and the first actual pressure parameter of the independent grinding area d is greater than the preset value, then the independent grinding area d is determined to be a faulty independent grinding area, and the actual pressure parameter of the independent grinding area d is adjusted to be less than the preset value compared with the corresponding first set value. For example, the actual pressure parameter of the independent grinding area d can be adjusted to 14N.

[0100] Then, the thin-film sensing sheet is removed, and the wafer is ground according to the corresponding first set value using the independent grinding area for applying pressure of the grinding head to be tested.

[0101] In summary, the grinding head inspection method provided by this invention sets the pressure parameters of the grinding head to a first preset value based on a database before grinding the wafer. This first preset value is within the acceptable pressure parameter range. Then, a thin-film sensor detects the first actual pressure parameter of the grinding head and determines whether the difference between the first actual pressure parameter and the first preset value is less than a preset value. If it is not less than the preset value, the actual pressure parameter of the grinding head is adjusted until the difference between it and the first preset value is less than the preset value. This ensures that the actual pressure parameter of the grinding head is within a reasonable pressure parameter range, avoiding a large error between the actual pressure parameter and the preset value that could affect the wafer grinding effect and improving wafer yield.

[0102] Furthermore, the present invention also provides a system for detecting the pressure parameters of the grinding head. Figure 5 This is a schematic diagram of a system for detecting the pressure parameters of a grinding head according to an embodiment of the present invention. Figure 5 As shown, the system includes:

[0103] Grinding head 01 to be tested;

[0104] Setting module 02 is used to set the usage mode of the grinding head to be tested, and based on the usage mode and a pre-established database, set the pressure parameter of the grinding head to be tested in the usage mode to a first set value;

[0105] Thin-film sensing sheet 03 is placed on the grinding head to be tested to detect the first actual pressure parameter of the grinding head to be tested;

[0106] Verification module 04 is used to verify whether the difference between the first actual pressure parameter and the first set value is less than a preset value; when the difference between the first actual pressure parameter and the first set value is less than the preset value, the thin film sensing sheet is removed, and the wafer is ground according to the first set value in the usage mode using the grinding head to be tested.

[0107] Optionally, the system further includes a database, which includes at least one usage mode of the grinding head and a range of qualified pressure parameters for the grinding head corresponding to the usage mode of the grinding head.

[0108] Optionally, the grinding head includes multiple concentric annular regions, each annular region constituting an independent grinding region. When the grinding head grinds the wafer, the independent grinding regions independently apply pressure to the wafer. The usage mode of the grinding head includes the position and number of the independent grinding regions in the grinding head used for applying pressure, and the qualified pressure parameter range includes the qualified range of the pressure parameters of the independent grinding regions.

[0109] Optionally, the system further includes a display device for receiving and displaying the first actual pressure parameter detected by the thin-film sensing sheet.

[0110] Optionally, the system further includes an adjustment module, used to adjust the actual pressure parameter of the grinding head to be less than the preset value when the difference between the first actual pressure parameter and the first set value is not less than a preset value.

[0111] In summary, the grinding head inspection system provided by this invention includes a setting module and a verification module. Before grinding a wafer with the grinding head under test, the setting module sets the pressure parameters of the grinding head under test to a first set value based on a database, and the first set value is within the acceptable pressure parameter range. Then, a thin-film sensor detects the first actual pressure parameter of the grinding head under test, and the verification module verifies whether the difference between the first actual pressure parameter and the first set value is less than a preset value. If it is not less than the preset value, the actual pressure parameter of the grinding head under test is adjusted until the difference between it and the first set value is less than the preset value. This ensures that the actual pressure parameter of the grinding head under test is within a reasonable pressure parameter range, avoiding a situation where a large error exists between the actual pressure parameter and the preset value when the grinding head grinds the wafer, which affects the wafer grinding effect and improves the wafer yield.

[0112] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple; relevant parts can be referred to the method section.

[0113] The above description is merely a description of preferred embodiments of the present invention and is not intended to limit the scope of the present invention in any way. Any changes or modifications made by those skilled in the art based on the above disclosure shall fall within the protection scope of the claims.

Claims

1. A method for detecting the pressure parameters of a grinding head, characterized in that, The method includes: Provide a grinding head to be tested; The usage mode of the grinding head to be tested is set, and based on the usage mode and a pre-established database, the pressure parameter of the grinding head to be tested in the usage mode is set to a first set value. The database includes at least one usage mode of the grinding head and a qualified pressure parameter range of the grinding head corresponding to the usage mode of the grinding head. A thin-film sensing sheet is placed on the grinding head to be tested, and the grinding head to be tested applies pressure to the thin-film sensing sheet according to the first set value in the usage mode, so that the thin-film sensing sheet detects the first actual pressure parameter of the grinding head to be tested, and verifies whether the difference between the first actual pressure parameter and the first set value is less than a preset value. When the difference between the first actual pressure parameter and the first set value is less than a preset value, the thin film sensing sheet is removed, and the wafer is ground in the usage mode according to the first set value using the grinding head to be tested.

2. The method for detecting the pressure parameters of the grinding head as described in claim 1, characterized in that, Before setting the usage mode of the grinding head to be tested, the method further includes: Establish the database; The database establishment method includes: Step 1, setting the usage mode of the grinding head and setting the pressure parameter of the grinding head in the usage mode as a second set value, placing a thin film sensing sheet on the grinding head, and using the grinding head to apply pressure to the thin film sensing sheet according to the second set value in the usage mode, so that the thin film sensing sheet can detect the second actual pressure parameter of the grinding head. Step 2: Remove the thin-film sensing sheet, and use the grinding head to grind the wafer according to the second set value in the usage mode, and record whether the ground wafer meets the process requirements; if it does, the second actual pressure parameter is a qualified pressure parameter, and collect the qualified pressure parameter; Furthermore, in the same usage mode, steps one and two are executed repeatedly to obtain multiple qualified pressure parameters, and the maximum and minimum values ​​are determined among the multiple qualified pressure parameters to form a range of qualified pressure parameters; The usage mode of the grinding head and the corresponding qualified pressure parameter range are stored in the database.

3. The method for detecting the pressure parameters of the grinding head as described in claim 1, characterized in that, Based on the usage mode and a pre-established database, the method for setting the pressure parameter of the grinding head to be tested in the usage mode to a first set value includes: Based on the usage mode of the grinding head to be tested, the corresponding qualified pressure parameter range is determined from the database; The first setting value is set based on the determined corresponding qualified pressure parameter range, and the first setting value is within the corresponding qualified pressure parameter range.

4. The method for detecting the pressure parameters of the grinding head as described in claim 1, characterized in that, When the difference between the first actual pressure parameter and the first set value is not less than the preset value, the actual pressure parameter of the grinding head is adjusted to be less than the preset value. Remove the thin-film sensor and use the grinding head to grind the wafer according to the first set value in the usage mode.

5. The method for detecting the pressure parameters of the grinding head as described in claim 1, characterized in that, The grinding head to be tested includes multiple concentric annular regions, each annular region constituting an independent grinding region. When the grinding head to be tested is used to grind the wafer, the independent grinding regions independently apply pressure to the wafer. The usage mode of the grinding head includes the position and number of independent grinding areas for applying pressure, and the qualified pressure parameter range of the grinding head is the qualified range of the pressure parameters of the independent grinding areas for applying pressure; the first setting value of the grinding head includes the first setting value of each independent grinding area for applying pressure.

6. The method for detecting the pressure parameters of the grinding head as described in claim 5, characterized in that, Before setting the usage mode of the grinding head to be tested, the method further includes: Establish the database; The database establishment method includes: Step 1, setting the usage mode of the grinding head to determine the independent grinding area in the grinding head for applying pressure, and pre-setting a second set value for the pressure parameters of each independent grinding area in the grinding head for applying pressure, and placing a thin film sensing sheet on the grinding head, applying pressure to the thin film sensing sheet using the independent grinding area for applying pressure, so as to detect the second actual pressure parameter of each independent grinding area for applying pressure using the thin film sensing sheet; Step 2: Remove the thin-film sensing sheet and use the grinding head to grind the wafer in the usage mode, and record whether the ground wafer meets the process requirements; if it does, the second actual pressure parameter is a qualified pressure parameter, and the qualified pressure parameter is collected. Furthermore, in the same usage mode, steps one and two are executed repeatedly to obtain multiple qualified pressure parameters corresponding to each independent grinding area used for pressure application, and the maximum and minimum values ​​are determined among the multiple qualified pressure parameters to form the range of qualified pressure parameters corresponding to each independent grinding area used for pressure application. The usage mode of the grinding head and the qualified pressure parameter range for each independent grinding area used for applying pressure are stored in the database.

7. The method for detecting the pressure parameters of the grinding head as described in claim 5, characterized in that, Based on the usage mode and a pre-established database, the method for setting the pressure parameter of the grinding head to be tested in the usage mode to a first set value includes: Based on the usage mode of the grinding head to be tested, the qualified pressure parameter range for each independent grinding disc area of ​​the grinding head to be tested for applying pressure is determined from the database; Based on the qualified pressure parameter range of each independent grinding disc area used for applying pressure, a first set value is set for the pressure parameter of each independent grinding disc area used for applying pressure in the grinding head, wherein the first set value of each independent grinding area used for applying pressure is within the corresponding qualified pressure parameter range.

8. The method for detecting the pressure parameters of the grinding head as described in claim 5, characterized in that, A method for applying pressure to a thin-film sensing sheet using the grinding head under test in the usage mode, so that the thin-film sensing sheet detects a first actual pressure parameter of the grinding head under test, includes: The thin-film sensing sheet is pressured using the independent grinding areas of the grinding head to be tested, so that the first actual pressure parameter of each independent grinding area for applying pressure can be detected by the thin-film sensing sheet.

9. The method for detecting the pressure parameters of the grinding head as described in claim 8, characterized in that, A method for verifying whether the difference between the first actual pressure parameter and the first set value is less than a preset value includes: verifying whether the difference between the first actual pressure parameter and the first set value for each independent grinding area used for pressure application is less than a preset value; When the difference between the first actual pressure parameter and the first set value of each independent grinding plate area used for applying pressure is less than the preset value, the thin film sensing sheet is removed, and the wafer is ground according to the corresponding first set value using each independent grinding plate area used for applying pressure of the grinding head to be tested.

10. The method for detecting the pressure parameters of the grinding head as described in claim 9, characterized in that, When the difference between the first actual pressure parameter and the first set value is not less than a preset value, the method further includes: determining the faulty independent grinding area and adjusting the actual pressure parameter of the faulty independent grinding area to be less than the preset value compared with the corresponding first set value; Remove the thin-film sensor and use the grinding head to grind the wafer according to the first set value in the usage mode.

11. The method for detecting the pressure parameters of the grinding head as described in claim 2, characterized in that, After detecting the first and second actual pressure parameters using the thin-film sensing sheet, a display device is used to display the first and second actual pressure parameters.

12. A system for detecting the pressure parameters of a grinding head, characterized in that, The system includes: The grinding head to be tested; The setting module is used to set the usage mode of the grinding head to be tested, and based on the usage mode and a pre-established database, set the pressure parameter of the grinding head to be tested in the usage mode to a first set value. A thin-film sensing sheet is placed on the grinding head to be tested to detect the first actual pressure parameter when the grinding head to be tested is pressed according to the first set value in the usage mode; The adjustment module is used to adjust the actual pressure parameter of the grinding head to be less than the preset value when the difference between the first actual pressure parameter and the first set value is not less than a preset value, remove the thin film sensing sheet, and use the grinding head to be tested to grind the wafer according to the first set value in the usage mode.

13. The detection system for the grinding head pressure parameters as described in claim 12, characterized in that, The system further includes a database, which includes at least one usage mode of the grinding head and a range of qualified pressure parameters for the grinding head corresponding to the usage mode of the grinding head.

14. The system for detecting the pressure parameters of the grinding head as described in claim 13, characterized in that, The grinding head includes multiple concentric annular regions, each annular region constituting an independent grinding region. When the grinding head grinds the wafer, the independent grinding regions independently apply pressure to the wafer. The usage mode of the grinding head includes the position and number of independent grinding areas for applying pressure in the grinding head, and the qualified pressure parameter range of the grinding head is the qualified range of the pressure parameters of the independent grinding areas for applying pressure.

15. The detection system for the grinding head pressure parameters as described in claim 12, characterized in that, The system further includes a display device connected to the thin-film sensor, for receiving and displaying the first actual pressure parameter detected by the thin-film sensor.

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