Silicon wafer cutting method and silicon wafer cutting device

Abstract

The invention provides a silicon wafer cutting method and a silicon wafer cutting device, and belongs to the technical field of semiconductor manufacturing. The silicon wafer cutting device comprises a mortar storage box which is configured to store and provide mortar and comprises a mortar outlet; the mortar valve is arranged at the mortar outlet, and the opening degree of the mortar valve can be adjusted; the steel wire conveying device is arranged below the mortar outlet; the surface laser measuring instrument is configured to detect the steel wire in the cutting process in real time and measure the cross section area of the passing steel wire; and the controller is configured to judge the amount of mortar carried by the steel wire per unit length according to the detected cross section area, and control the valve opening degree of the mortar valve according to the amount of mortar. The method can greatly reduce steel wire breakage, improve silicon wafer cutting surface quality and reduce mortar waste.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing technology, and in particular to a silicon wafer cutting method and a silicon wafer cutting device. Background Art

[0002] During the wafer production process, single crystal silicon rods need to be cut into silicon wafers of uniform thickness. Currently, the cutting is done by rubbing mortar attached to a steel wire against the single crystal silicon rod. However, the steel wire may break during the cutting process, which will cause serious wire marks on the surface of the silicon wafer, causing the product to be downgraded or scrapped. In severe cases, the entire single crystal silicon rod will be scrapped. Summary of the invention

[0003] In order to solve the above technical problems, the present invention provides a silicon wafer cutting method and a silicon wafer cutting device, which can significantly reduce the occurrence of steel wire breakage, improve the quality of the silicon wafer cutting surface, and reduce mortar waste.

[0004] In order to achieve the above object, the technical solution adopted by the embodiment of the present invention is:

[0005] A silicon wafer cutting device, comprising:

[0006] a mortar storage box configured to store and provide mortar, including a mortar outlet;

[0007] A mortar valve with an adjustable opening and closing degree arranged at the mortar outlet;

[0008] A steel wire conveyor disposed below the mortar outlet;

[0009] A surface laser measuring instrument is configured to detect the steel wire being cut in real time and measure the cross-sectional area of ​​the steel wire passing through;

[0010] The controller is configured to determine the amount of mortar carried by the steel wire per unit length according to the detected cross-sectional area, and control the valve opening of the mortar valve according to the amount of mortar.

[0011] In some embodiments, the controller is configured to subtract the cross-sectional area of ​​the steel wire from the detected cross-sectional area to obtain a difference, and determine the amount of mortar carried by a unit length of the steel wire based on the difference.

[0012] In some embodiments, the steel wire conveying device comprises:

[0013] A steel wire inlet winding reel and a steel wire outlet winding reel are arranged opposite to each other.

[0014] In some embodiments, the surface laser measuring instrument is disposed between the steel wire inlet winding shaft and the steel wire outlet winding shaft.

[0015] In some embodiments, the controller is configured to reduce the valve opening of the mortar valve by a preset step size when the amount of mortar carried by a unit length of the steel wire is greater than a preset threshold value; and to increase the valve opening of the mortar valve by a preset step size when the amount of mortar carried by a unit length of the steel wire is less than a preset threshold value.

[0016] In some embodiments, the preset step size is 1%.

[0017] The embodiment of the present invention further provides a silicon wafer cutting method, which is used in the silicon wafer cutting device as described above, and the method comprises:

[0018] Use a surface laser measuring instrument to perform real-time detection of the steel wire being cut and measure the cross-sectional area of ​​the steel wire passing through;

[0019] The amount of mortar carried by the steel wire per unit length is determined based on the detected cross-sectional area, and the valve opening of the mortar valve is controlled based on the amount of mortar.

[0020] In some embodiments, determining the amount of mortar carried by the steel wire per unit length according to the detected cross-sectional area includes:

[0021] The detected cross-sectional area is subtracted from the cross-sectional area of ​​the steel wire to obtain a difference, and the amount of mortar carried by the steel wire per unit length is determined based on the difference.

[0022] In some embodiments, controlling the valve opening of the mortar valve according to the mortar amount includes:

[0023] When the amount of mortar carried by the steel wire per unit length is greater than a preset threshold, the valve opening of the mortar valve is reduced by a preset step size; when the amount of mortar carried by the steel wire per unit length is less than the preset threshold, the valve opening of the mortar valve is increased by a preset step size.

[0024] An embodiment of the present invention further provides a computer-readable storage medium, wherein the computer-readable storage medium stores at least one instruction, and the at least one instruction is used to be executed by a processor to implement the above-mentioned silicon wafer cutting method.

[0025] The beneficial effects of the present invention are:

[0026] In this embodiment, a surface laser measuring instrument is used to perform real-time detection on the steel wire being cut, and the cross-sectional area of ​​the steel wire passing through is measured. The amount of mortar carried by the steel wire is judged by the detected cross-sectional area. If the cross-sectional area is large, it indicates that the steel wire carries a large amount of mortar. At this time, there are more mortar particles ground with the silicon rod during the cutting process, and the steel wire is not easy to break. If the cross-sectional area is small, there are fewer mortar particles ground with the silicon rod during the cutting process, and there is even a phenomenon of dry grinding of the steel wire, and the steel wire is easy to break. By controlling the opening of the mortar valve through the real-time measurement of the cross-sectional area of ​​the steel wire, the amount of mortar carried on the steel wire can be ensured to be consistent, the breakage of the steel wire can be greatly reduced, the quality of the cutting surface of the silicon wafer is improved, and the uniformity of the cut silicon wafer is improved. In addition, by controlling the opening of the mortar valve through the real-time measurement of the cross-sectional area of ​​the steel wire, the mortar waste caused by a large amount of mortar can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 A schematic diagram showing the structure of a silicon wafer cutting device according to an embodiment of the present invention;

[0028] Figure 2 A schematic diagram showing a flow chart of a silicon wafer cutting method according to an embodiment of the present invention.

[0029] Reference numerals

[0030] 01Mortar Storage Box

[0031] 02 Mortar export

[0032] 03 Mortar valve

[0033] 04 Steel Wire

[0034] 05 Surface laser measuring instrument

[0035] 06 Steel wire feeding winding spool

[0036] 07 Steel wire winding spool DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0038] The present invention provides a silicon wafer cutting method and a silicon wafer cutting device, which can significantly reduce the situation of steel wire breakage, improve the quality of the silicon wafer cutting surface, and reduce mortar waste.

[0039] The embodiment of the present invention provides a silicon wafer cutting device, such as Figure 1 As shown, including:

[0040] A mortar storage box 01, configured to store and provide mortar, the mortar storage box 01 comprises a mortar outlet 02;

[0041] A mortar valve 03 with an adjustable opening and closing degree arranged at the mortar outlet 02;

[0042] A steel wire conveying device arranged below the mortar outlet 02;

[0043] The surface laser measuring instrument 05 is configured to detect the steel wire 04 being cut in real time and measure the cross-sectional area of ​​the steel wire passing through;

[0044] The controller is configured to determine the amount of mortar carried by the steel wire per unit length according to the detected cross-sectional area, and control the valve opening of the mortar valve according to the amount of mortar.

[0045] In this embodiment, a surface laser measuring instrument is used to perform real-time detection on the steel wire being cut, and the cross-sectional area of ​​the steel wire passing through is measured. The amount of mortar carried by the steel wire is judged by the detected cross-sectional area. If the cross-sectional area is large, it indicates that the steel wire carries a large amount of mortar. At this time, there are more mortar particles ground with the silicon rod during the cutting process, and the steel wire is not easy to break. If the cross-sectional area is small, there are fewer mortar particles ground with the silicon rod during the cutting process, and there is even a phenomenon of dry grinding of the steel wire, and the steel wire is easy to break. By controlling the opening of the mortar valve through the real-time measurement of the cross-sectional area of ​​the steel wire, the amount of mortar carried on the steel wire can be ensured to be consistent, the breakage of the steel wire can be greatly reduced, the quality of the cutting surface of the silicon wafer is improved, and the uniformity of the cut silicon wafer is improved. In addition, by controlling the opening of the mortar valve through the real-time measurement of the cross-sectional area of ​​the steel wire, the mortar waste caused by a large amount of mortar can be reduced.

[0046] In some embodiments, the controller is configured to subtract the cross-sectional area of ​​the steel wire from the detected cross-sectional area to obtain a difference, and determine the amount of mortar carried by a unit length of the steel wire based on the difference.

[0047] In this embodiment, after the specifications of the steel wire are determined, the cross-sectional area of ​​the steel wire is known. When the steel wire passes through the surface laser measuring instrument, the total cross-sectional area of ​​the steel wire and the mortar carried on it can be detected, and the detected cross-sectional area is subtracted from the known cross-sectional area of ​​the steel wire to obtain a difference. According to the difference, the distribution of the mortar on the steel wire can be obtained, and then the amount of mortar carried by the steel wire per unit length can be determined. Among them, when the viscosity of the mortar is fixed, the valve opening of the mortar valve is linearly related to the amount of mortar attached to the steel wire, that is, the larger the valve opening of the mortar valve, the larger the amount of mortar attached to the steel wire; that is, the smaller the opening of the mortar valve, the smaller the amount of mortar attached to the steel wire.

[0048] In some embodiments, Figure 2As shown, the steel wire conveying device comprises:

[0049] The steel wire inlet winding reel 06 and the steel wire outlet winding reel 07 are arranged opposite to each other.

[0050] The steel wire 04 located between the steel wire inlet winding shaft 06 and the steel wire outlet winding shaft 07 is used to cut the silicon rod. Therefore, in order to accurately obtain the amount of mortar attached to the steel wire 04, as shown in FIG. Figure 1 As shown, the surface laser measuring instrument 05 is arranged between the steel wire inlet winding shaft 06 and the steel wire outlet winding shaft 07 .

[0051] In some embodiments, the controller is configured to reduce the valve opening of the mortar valve by a preset step length when the amount of mortar carried by the steel wire per unit length is greater than a preset threshold; and to increase the valve opening of the mortar valve by a preset step length when the amount of mortar carried by the steel wire per unit length is less than the preset threshold. The value of the preset step length may be 1%, but the preset step length is not limited to 1%, and may also be other values, such as 0.5%, 1.5%, etc.

[0052] The above preset threshold can be predetermined based on a large amount of experimental data. When the amount of mortar carried by the steel wire per unit length is equal to the preset threshold, the quality of the cut surface of the silicon wafer can be guaranteed, and the steel wire will not break. When the amount of mortar carried by the steel wire per unit length is greater than the preset threshold, the valve opening of the current mortar valve can be reduced by 1%, and then the amount of mortar carried by the steel wire per unit length is detected again. If the amount of mortar carried by the steel wire per unit length is still greater than the preset threshold, the valve opening of the mortar valve continues to be reduced; if the amount of mortar carried by the steel wire per unit length is equal to the preset threshold, the valve opening of the mortar valve is no longer reduced. When the amount of mortar carried by the steel wire per unit length is less than the preset threshold, the valve opening of the current mortar valve can be increased by 1%, and then the amount of mortar carried by the steel wire per unit length is detected again. If the amount of mortar carried by the steel wire per unit length is still less than the preset threshold, the valve opening of the mortar valve continues to be increased; if the amount of mortar carried by the steel wire per unit length is equal to the preset threshold, the valve opening of the mortar valve is no longer increased.

[0053] The embodiment of the present invention also provides a silicon wafer cutting method, which is used in the silicon wafer cutting device as described above. Figure 2 As shown, the method includes:

[0054] Step 101: Use a surface laser measuring instrument to perform real-time detection on the steel wire being cut, and measure the cross-sectional area of ​​the steel wire passing through;

[0055] Step 102: Determine the amount of mortar carried by the steel wire per unit length based on the detected cross-sectional area, and control the valve opening of the mortar valve based on the amount of mortar.

[0056] In this embodiment, a surface laser measuring instrument is used to perform real-time detection on the steel wire being cut, and the cross-sectional area of ​​the steel wire passing through is measured. The amount of mortar carried by the steel wire is judged by the detected cross-sectional area. If the cross-sectional area is large, it indicates that the steel wire carries a large amount of mortar. At this time, there are more mortar particles ground with the silicon rod during the cutting process, and the steel wire is not easy to break. If the cross-sectional area is small, there are fewer mortar particles ground with the silicon rod during the cutting process, and there is even a phenomenon of dry grinding of the steel wire, and the steel wire is easy to break. By controlling the opening of the mortar valve through the real-time measurement of the cross-sectional area of ​​the steel wire, the amount of mortar carried on the steel wire can be ensured to be consistent, the breakage of the steel wire can be greatly reduced, the quality of the cutting surface of the silicon wafer is improved, and the uniformity of the cut silicon wafer is improved. In addition, by controlling the opening of the mortar valve through the real-time measurement of the cross-sectional area of ​​the steel wire, the mortar waste caused by a large amount of mortar can be reduced.

[0057] In some embodiments, determining the amount of mortar carried by the steel wire per unit length according to the detected cross-sectional area includes:

[0058] The detected cross-sectional area is subtracted from the cross-sectional area of ​​the steel wire to obtain a difference, and the amount of mortar carried by the steel wire per unit length is determined based on the difference.

[0059] In this embodiment, after the specifications of the steel wire are determined, the cross-sectional area of ​​the steel wire is known. When the steel wire passes through the surface laser measuring instrument, the total cross-sectional area of ​​the steel wire and the mortar carried on it can be detected, and the detected cross-sectional area is subtracted from the known cross-sectional area of ​​the steel wire to obtain a difference. According to the difference, the distribution of the mortar on the steel wire can be obtained, and then the amount of mortar carried by the steel wire per unit length can be determined. Among them, when the viscosity of the mortar is fixed, the valve opening of the mortar valve is linearly related to the amount of mortar attached to the steel wire, that is, the larger the valve opening of the mortar valve, the larger the amount of mortar attached to the steel wire; that is, the smaller the opening of the mortar valve, the smaller the amount of mortar attached to the steel wire.

[0060] In some embodiments, controlling the valve opening of the mortar valve according to the mortar amount includes:

[0061] When the amount of mortar carried by the steel wire per unit length is greater than a preset threshold, the valve opening of the mortar valve is reduced by a preset step size; when the amount of mortar carried by the steel wire per unit length is less than the preset threshold, the valve opening of the mortar valve is increased by a preset step size.

[0062] The preset step length may be set to a value of 1%. Of course, the preset step length is not limited to 1%, and may also be other values, such as 0.5%, 1.5%, etc.

[0063] The above preset threshold can be predetermined based on a large amount of experimental data. When the amount of mortar carried by the steel wire per unit length is equal to the preset threshold, the quality of the cut surface of the silicon wafer can be guaranteed, and the steel wire will not break. When the amount of mortar carried by the steel wire per unit length is greater than the preset threshold, the valve opening of the current mortar valve can be reduced by 1%, and then the amount of mortar carried by the steel wire per unit length is detected again. If the amount of mortar carried by the steel wire per unit length is still greater than the preset threshold, the valve opening of the mortar valve continues to be reduced; if the amount of mortar carried by the steel wire per unit length is equal to the preset threshold, the valve opening of the mortar valve is no longer reduced. When the amount of mortar carried by the steel wire per unit length is less than the preset threshold, the valve opening of the current mortar valve can be increased by 1%, and then the amount of mortar carried by the steel wire per unit length is detected again. If the amount of mortar carried by the steel wire per unit length is still less than the preset threshold, the valve opening of the mortar valve continues to be increased; if the amount of mortar carried by the steel wire per unit length is equal to the preset threshold, the valve opening of the mortar valve is no longer increased.

[0064] An embodiment of the present invention further provides a computer-readable storage medium, wherein the computer-readable storage medium stores at least one instruction, and the at least one instruction is used to be executed by a processor to implement the above-mentioned silicon wafer cutting method.

[0065] Those skilled in the art should be aware that in one or more of the above examples, the functions described in the embodiments of the present application can be implemented with hardware, software, firmware, or any combination thereof. When implemented using software, these functions can be stored in a computer-readable medium or transmitted as one or more instructions or codes on a computer-readable medium. Computer-readable media include computer storage media and communication media, wherein the communication media include any media that facilitates the transmission of a computer program from one place to another. The storage medium can be any available medium that a general or special-purpose computer can access.

[0066] It should be noted that each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the embodiments, since they are basically similar to the product embodiments, the description is relatively simple, and the relevant parts can be referred to the partial description of the product embodiments.

[0067] In the description of the above embodiments, specific features, structures, materials or characteristics may be combined in a suitable manner in any one or more embodiments or examples.

[0068] The above is only a specific embodiment of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any person skilled in the art who is familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present disclosure, which should be included in the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be based on the protection scope of the claims.

Claims

1. A silicon wafer cutting device, characterized in that: include: a mortar storage box configured to store and provide mortar, including a mortar outlet; A mortar valve with an adjustable opening and closing degree arranged at the mortar outlet; A steel wire conveyor disposed below the mortar outlet; A surface laser measuring instrument is configured to detect the steel wire being cut in real time and measure the cross-sectional area of ​​the steel wire passing through; The controller is configured to determine the amount of mortar carried by the steel wire per unit length according to the detected cross-sectional area, and control the valve opening of the mortar valve according to the amount of mortar.

2. The silicon wafer cutting device according to claim 1, characterized in that: The controller is configured to subtract the cross-sectional area of ​​the steel wire from the detected cross-sectional area to obtain a difference, and determine the amount of mortar carried by a unit length of the steel wire according to the difference.

3. The silicon wafer cutting device according to claim 1, characterized in that: The steel wire conveying device comprises: A steel wire inlet winding reel and a steel wire outlet winding reel are arranged opposite to each other.

4. The silicon wafer cutting device according to claim 3, characterized in that: The surface laser measuring instrument is arranged between the steel wire inlet winding shaft and the steel wire outlet winding shaft.

5. The silicon wafer cutting device according to claim 1, characterized in that: The controller is configured to reduce the valve opening of the mortar valve in a preset step size when the amount of mortar carried by a unit length of the steel wire is greater than a preset threshold; and to increase the valve opening of the mortar valve in a preset step size when the amount of mortar carried by a unit length of the steel wire is less than the preset threshold.

6. The silicon wafer cutting device according to claim 5, characterized in that: The preset step size is 1%.

7. A silicon wafer cutting method, characterized in that: For use in a silicon wafer cutting device as claimed in any one of claims 1 to 6, the method comprising: Use a surface laser measuring instrument to perform real-time detection of the steel wire being cut and measure the cross-sectional area of ​​the steel wire passing through; The amount of mortar carried by the steel wire per unit length is determined based on the detected cross-sectional area, and the valve opening of the mortar valve is controlled based on the amount of mortar.

8. The silicon wafer cutting method according to claim 7, characterized in that: The method of judging the amount of mortar carried by the steel wire per unit length according to the detected cross-sectional area comprises: The detected cross-sectional area is subtracted from the cross-sectional area of ​​the steel wire to obtain a difference, and the amount of mortar carried by the steel wire per unit length is determined based on the difference.

9. The silicon wafer cutting method according to claim 7, characterized in that: The controlling the valve opening of the mortar valve according to the mortar amount comprises: When the amount of mortar carried by the steel wire per unit length is greater than a preset threshold, the valve opening of the mortar valve is reduced by a preset step size; when the amount of mortar carried by the steel wire per unit length is less than the preset threshold, the valve opening of the mortar valve is increased by a preset step size.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores at least one instruction, and the at least one instruction is used to be executed by a processor to implement the silicon wafer cutting method according to any one of claims 7 to 9.

Images