Method and device for removing bulk metal in silicon wafer
By subjecting silicon wafers with different oxygen contents to temperature treatment and cleaning, a bulk metal diffusion model was generated, which solved the problem of low bulk metal removal efficiency in silicon wafers and achieved an effective reduction in bulk metal content in silicon wafers.
Patent Information
- Application Number
- CN202511110372.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-08
- Publication Date
- 2025-11-14
AI Technical Summary
In existing technologies, the efficiency of bulk metal removal during silicon wafer manufacturing is poor, which cannot effectively reduce the content of bulk metal in silicon wafers, especially the problem of metal diffusion into the silicon wafer during etching.
By heating multiple silicon wafers with different oxygen contents at different temperatures, a bulk metal diffusion model is generated. Based on the model, the silicon wafers to be treated are adaptively heated and cleaned to remove the bulk metal from the surface of the silicon wafers.
This effectively reduces the bulk metal content in silicon wafers, improves the purity of silicon wafers, and meets the metal specification requirements of subsequent devices.
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Figure CN120954971A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of semiconductor manufacturing technology, and in particular to a method and apparatus for removing bulk metal from a silicon wafer. Background Technology
[0002] Silicon wafers are the substrate material for integrated circuit (IC) devices. With the continuous development of IC technology, the linewidth of devices is constantly shrinking, leading to increasingly higher requirements for the metal content on the silicon wafer surface and within the wafer itself. During the silicon wafer manufacturing process, some steps inevitably introduce metals into the wafer. For example, after processes such as wafer grinding, a certain amount of metal may remain in the damaged layer on the silicon wafer surface.
[0003] To remove these damaged layers, acidic or alkaline chemicals are typically used for etching. To ensure etching speed, the chemical etching solution is usually maintained at a certain temperature. Therefore, while removing the damaged layer on the silicon wafer surface, the metal enriched on the silicon wafer surface and in the etching solution also diffuses into the silicon wafer, resulting in a high bulk metal content. Related technologies usually involve uniform low-temperature oxidation cleaning or oxidation to remove the bulk metal from the silicon wafer. However, these methods do not take into account the different properties of various silicon wafers, leading to poor bulk metal removal efficiency. Summary of the Invention
[0004] To address the aforementioned technical problems, this invention provides a method and apparatus for removing bulk metal from silicon wafers, which can effectively reduce the content of bulk metal in silicon wafers.
[0005] To achieve the above objectives, the technical solution adopted in the embodiments of the present invention is as follows:
[0006] In a first aspect, the present invention provides a method for removing bulk metal from a silicon wafer, comprising:
[0007] Multiple sets of first silicon wafers are obtained, and multiple temperature values are set in order of size. Each set of first silicon wafers includes multiple first silicon wafers. The oxygen content of the first silicon wafers included in each set of first silicon wafers is the same, while the oxygen content of the first silicon wafers included in different sets of first silicon wafers is different.
[0008] Based on each of the plurality of temperature values, the plurality of first silicon wafer sets are heated sequentially to obtain a plurality of bulk metal diffusion results. Each bulk metal precipitation result is used to indicate the diffusion of bulk metal on the first silicon wafer at the corresponding oxygen content and temperature value.
[0009] A bulk metal diffusion model is generated based on the multiple bulk metal precipitation results. The metal diffusion model is used to represent the diffusion of bulk metal in silicon wafers under different oxygen contents and different temperature values.
[0010] Based on the bulk metal diffusion model and the oxygen content of the silicon wafer to be treated, the silicon wafer to be treated is heated and then cleaned to remove the bulk metal from the surface of the silicon wafer.
[0011] In some embodiments, the step of sequentially heating the plurality of first silicon wafer assemblies based on each of the plurality of temperature values to obtain a plurality of bulk metal diffusion results includes:
[0012] Based on each of the plurality of temperature values, the plurality of first silicon wafer sets are sequentially heated to obtain a plurality of second silicon wafer sets, wherein each second silicon wafer set includes a plurality of second silicon wafers after the plurality of first silicon wafers have been heated;
[0013] The bulk metal content on the surface of the multiple second silicon wafers included in the multiple second silicon wafer sets is detected to obtain multiple bulk metal diffusion results.
[0014] In some embodiments, the step of sequentially heating the plurality of first silicon wafer sets based on each of the plurality of temperature values to obtain a plurality of second silicon wafer sets includes:
[0015] For each set of first silicon wafers, the plurality of first silicon wafers included in each set of first silicon wafers are cleaned to obtain a plurality of cleaned first silicon wafers;
[0016] Based on the plurality of temperature values, the multiple first silicon wafers after cleaning are grouped to obtain multiple silicon wafer groups, and the multiple silicon wafer groups correspond one-to-one with the plurality of temperature values;
[0017] The multiple silicon wafer groups are heated according to the temperature values corresponding to the silicon wafer groups to obtain the second silicon wafer set.
[0018] In some embodiments, detecting the bulk metal content on the surfaces of the plurality of second silicon wafers included in the plurality of second silicon wafer assemblies to obtain multiple bulk metal diffusion results includes:
[0019] For each of the second silicon wafer sets, the bulk metal content on the surface of the plurality of second silicon wafers included in the second silicon wafer set is measured to obtain first measurement data;
[0020] After treating the plurality of second silicon wafers with polyuridine triphosphate, the bulk metal content on the surface of the plurality of second silicon wafers is measured again to obtain second measurement data;
[0021] The bulk metal diffusion results are generated based on the first measurement data and the second measurement data.
[0022] In some embodiments, the step of heating the silicon wafer to be treated based on the bulk metal diffusion model and the oxygen content corresponding to the silicon wafer to be treated, and then cleaning the heated silicon wafer to remove the bulk metal from the surface of the silicon wafer to be treated, includes:
[0023] Determine the oxygen content corresponding to the silicon wafer to be processed;
[0024] Based on the oxygen content corresponding to the silicon wafer to be processed, the target temperature value of the silicon wafer to be processed is determined by querying the bulk metal diffusion model. The target temperature value is the heating temperature value of the silicon wafer to be processed.
[0025] The silicon wafer to be processed is heated based on the target temperature value, and then the heated silicon wafer is cleaned to remove the bulk metal on the surface of the silicon wafer.
[0026] In some embodiments, each of the plurality of temperature values is within the range of 60°C to 120°C, and the difference between any two adjacent temperature values is the same.
[0027] In a second aspect, the present invention provides an apparatus for removing bulk metal from a silicon wafer, the apparatus comprising:
[0028] The acquisition module is used to acquire multiple sets of first silicon wafers and set multiple temperature values in order of size. Each set of first silicon wafers includes multiple first silicon wafers. The oxygen content of the first silicon wafers included in each set of first silicon wafers is the same, while the oxygen content of the first silicon wafers included in different sets of first silicon wafers is different.
[0029] The heating module is used to sequentially heat the plurality of first silicon wafer sets based on each of the plurality of temperature values to obtain a plurality of bulk metal diffusion results. Each bulk metal precipitation result is used to indicate the diffusion of bulk metal on the first silicon wafer at the corresponding oxygen content and temperature value.
[0030] A generation module is used to generate a bulk metal diffusion model based on the multiple bulk metal precipitation results. The metal diffusion model is used to represent the diffusion of bulk metals in a silicon wafer under different oxygen contents and different temperature values.
[0031] The processing module is used to heat the silicon wafer to be processed based on the bulk metal diffusion model and the oxygen content corresponding to the silicon wafer to be processed, and to clean the heated silicon wafer to be processed in order to remove the bulk metal on the surface of the silicon wafer to be processed.
[0032] Thirdly, the present invention also provides an electronic device including a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein the computer program, when executed by the processor, performs the steps of the method described in the first aspect above.
[0033] Fourthly, the present invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the method described in the first aspect above.
[0034] Fifthly, the present invention also provides a computer program product, including computer instructions that, when executed by a processor, implement the steps of the method described in the first aspect above.
[0035] The beneficial effects of this invention are:
[0036] The present invention provides a method for heating multiple sets of first silicon wafers with different oxygen contents at different temperature values to obtain bulk metal diffusion results for each set of first silicon wafers. Based on these bulk metal diffusion results, a bulk metal diffusion model is generated to indicate the diffusion of bulk metal in the silicon wafers under different oxygen contents and temperature values. Therefore, when processing silicon wafers, the silicon wafers are adaptively heated according to the metal diffusion model and the corresponding oxygen content, and then cleaned after heating, thereby effectively reducing the bulk metal content in the silicon wafers. Attached Figure Description
[0037] To more clearly illustrate the technical solution of the present invention, the accompanying drawings used in the description of the present invention will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0038] Figure 1 This is a flowchart of a method for removing bulk metal from a silicon wafer provided in an embodiment of the present invention;
[0039] Figure 2 This is a schematic diagram showing the relationship between Cu content in silicon wafers with different oxygen contents in an embodiment of the present invention;
[0040] Figure 3 This is a schematic diagram illustrating the relationship between different temperatures and the diffusion output ratio of Bulk Cu in an embodiment of the present invention;
[0041] Figure 4 This is a schematic diagram of the theoretical model of the bulk metal at different temperatures in the embodiments of the present invention;
[0042] Figure 5 This is a graph showing the relationship between the decrease in Bulk Cu before and after heat treatment at a specific temperature in an embodiment of the present invention;
[0043] Figure 6 This is a structural diagram of a device for removing bulk metal from a silicon wafer provided in an embodiment of the present invention;
[0044] Figure 7 This is a structural diagram of an electronic device provided in an embodiment of the present invention. Detailed Implementation
[0045] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention are within the scope of protection of the present invention.
[0046] This invention provides a method and apparatus for removing bulk metals from silicon wafers, which can effectively reduce the content of bulk metals in silicon wafers.
[0047] This invention provides a method for removing bulk metal from a silicon wafer, such as... Figure 1 As shown, it includes:
[0048] Step 101: Obtain multiple sets of first silicon wafers and set multiple temperature values in order of size. Each set of first silicon wafers includes multiple first silicon wafers. The oxygen content of the first silicon wafers included in each set of first silicon wafers is the same, while the oxygen content of the first silicon wafers included in different sets of first silicon wafers is different.
[0049] In this embodiment, each of the multiple sets of first silicon wafers includes multiple first silicon wafers. It should be noted that the number of first silicon wafers can be the same or different; this invention uses the example of multiple sets of first silicon wafers having the same number. For example, there are 8 sets of first silicon wafers, each set containing 8 first silicon wafers. Within the same set, all the first silicon wafers have the same oxygen content, while in different sets, the oxygen content differs, facilitating comparative testing. For example, the oxygen content in the 8 sets of silicon wafers could be 1%, 2%, ..., 8%, respectively. The multiple sets of first silicon wafers are processed using multiple set temperature values, which are multiple temperature values ordered sequentially according to their magnitude. In this embodiment, the range of the multiple temperature values can be 60℃ to 120℃; for example, the multiple temperature values could be 60℃, 80℃, 100℃, and 120℃.
[0050] Each silicon wafer includes a bulk metal, which typically refers to the metallic material used in semiconductor manufacturing to create various electronic components. These metals are usually located inside the silicon wafer or attached to its surface, serving functions such as conductivity, connectivity, and heat dissipation. Common bulk metals include aluminum (Al), copper (Cu), and titanium (Ti). These metals have different applications and roles in different manufacturing processes. In this invention, copper is used as an example to illustrate the bulk metal included in the silicon wafer. The bulk Cu within the silicon wafer is mainly affected by the doping amount, oxygen content, and manufacturing process. Reducing the bulk Cu in the final product through doping amount and manufacturing process is costly and the reduction effect is not significant. Changing the etching temperature and etching alkali concentration in the semi-finished product state has little effect on reducing the bulk Cu within the silicon wafer. Therefore, the relationship between oxygen content and bulk Cu is analyzed, such as... Figure 2 As shown, Figure 2 This is a schematic diagram showing the relationship between Cu content within silicon wafers with different oxygen contents. Figure 2 It can be seen that there is a certain linear relationship between the oxygen content within the silicon wafer and Bulk Cu, where a1 and b1 represent different oxygen contents, and c is a critical value. When the oxygen content is below c, the change trend of Bulk Cu with oxygen content is relatively stable. When the oxygen content is above c, the change trend of Bulk Cu with oxygen content is obvious.
[0051] Step 102: Based on each of the multiple temperature values, heat the multiple sets of first silicon wafers sequentially to obtain multiple bulk metal diffusion results. Each bulk metal precipitation result is used to indicate the diffusion of bulk metal on the first silicon wafer under the corresponding oxygen content and temperature value.
[0052] In this embodiment, multiple sets of first silicon wafers are heated according to multiple set temperature values to obtain multiple bulk metal diffusion results. For example, taking a set of first silicon wafers as an example, the set of first silicon wafers includes 8 silicon wafers. Therefore, 2 first silicon wafers are heated at 60°C, 2 first silicon wafers are heated at 80°C, 2 first silicon wafers are heated at 100°C, and the remaining two first silicon wafers are heated at 120°C to obtain multiple bulk metal diffusion results. The bulk metal diffusion results are obtained by measuring the metal on the surface of the silicon wafers.
[0053] Step 103: Generate a bulk metal diffusion model based on the multiple bulk metal precipitation results. The metal diffusion model is used to represent the diffusion of bulk metal in the silicon wafer under different oxygen contents and different temperature values.
[0054] The metal diffusion results from multiple volumes were analyzed to obtain a metal diffusion model. It should be noted that the metal diffusion model can be, for example,... Figure 3 The relationship diagram shown is composed of... Figure 3 It can be seen that the diffusion out ratio of Bulk Cu varies at different temperatures, and the diffusion out ratio of Bulk Cu is approximately positively correlated with temperature.
[0055] Step 104: Based on the bulk metal diffusion model and the oxygen content corresponding to the silicon wafer to be processed, heat the silicon wafer to be processed and clean it after heating to remove the bulk metal on the surface of the silicon wafer to be processed.
[0056] In this embodiment, the oxygen content of the silicon wafer to be treated is determined, and an appropriate temperature is selected to heat the silicon wafer according to the metal diffusion model. After the heat treatment is completed, the surface of the silicon wafer to be treated is cleaned to remove the bulk metal on the surface of the silicon wafer, thereby reducing the content of bulk metal in the silicon wafer.
[0057] The present invention provides a method for heating multiple sets of first silicon wafers with different oxygen contents at different temperature values to obtain bulk metal diffusion results for each set of first silicon wafers. Based on these bulk metal diffusion results, a bulk metal diffusion model is generated to indicate the diffusion of bulk metal in the silicon wafers under different oxygen contents and temperature values. Therefore, when processing silicon wafers, the silicon wafers are adaptively heated according to the metal diffusion model and the corresponding oxygen content, and then cleaned after heating, thereby effectively reducing the bulk metal content in the silicon wafers.
[0058] In some embodiments, the step of sequentially heating the plurality of first silicon wafer assemblies based on each of the plurality of temperature values to obtain a plurality of bulk metal diffusion results includes:
[0059] Based on each of the plurality of temperature values, the plurality of first silicon wafer sets are sequentially heated to obtain a plurality of second silicon wafer sets, wherein each second silicon wafer set includes a plurality of second silicon wafers after the plurality of first silicon wafers have been heated;
[0060] The bulk metal content on the surface of the multiple second silicon wafers included in the multiple second silicon wafer sets is detected to obtain multiple bulk metal diffusion results. In this embodiment, multiple first silicon wafer sets are heated according to multiple set temperature values to obtain multiple second silicon wafer sets, wherein each second silicon wafer set includes multiple second silicon wafers after heat treatment.
[0061] After heating, the bulk metal diffuses to the surface of multiple second silicon wafers, thereby detecting the bulk metal content on the surface of multiple second silicon wafers and obtaining multiple bulk metal diffusion results. Subsequently, the multiple bulk metal diffusion results can be analyzed to generate a bulk metal diffusion model.
[0062] In some embodiments, the step of sequentially heating the plurality of first silicon wafer sets based on each of the plurality of temperature values to obtain a plurality of second silicon wafer sets includes:
[0063] For each set of first silicon wafers, the plurality of first silicon wafers included in each set of first silicon wafers are cleaned to obtain a plurality of cleaned first silicon wafers;
[0064] Based on the plurality of temperature values, the multiple first silicon wafers after cleaning are grouped to obtain multiple silicon wafer groups, and the multiple silicon wafer groups correspond one-to-one with the plurality of temperature values;
[0065] The multiple silicon wafer groups are heated according to the temperature values corresponding to the silicon wafer groups to obtain the second silicon wafer set.
[0066] In this embodiment, before heating the multiple first silicon wafer sets, the silicon wafers need to be cleaned to ensure the accuracy of the measurement of metal diffusion in the silicon wafers. This embodiment uses a single silicon wafer set as an example. First, the multiple first silicon wafers are cleaned to obtain cleaned first silicon wafers. For example, a cleaning machine can be used to clean both sides of the silicon wafers.
[0067] Multiple first silicon wafers are grouped according to multiple temperature values. In some embodiments, each of the multiple temperature values is within the range of 60°C to 120°C, and the difference between any two adjacent temperature values is the same.
[0068] For example, the multiple temperature values can be 60℃, 80℃, 100℃, and 120℃. Therefore, the multiple cleaned first silicon wafers are grouped into four wafer groups corresponding to the four temperature values. For example, if the multiple first silicon wafers include eight wafers, then two cleaned first silicon wafers are assigned to the wafer group corresponding to 60℃, two cleaned first silicon wafers to the wafer group corresponding to 80℃, two cleaned first silicon wafers to the wafer group corresponding to 100℃, and two cleaned first silicon wafers to the wafer group corresponding to 120℃. Heating is then performed according to the corresponding temperature. It should be noted that the heating method can be oven heating, but this embodiment is not specifically limited to this method.
[0069] Therefore, by processing multiple sets of first silicon wafers separately, multiple sets of second silicon wafers are finally obtained.
[0070] In some embodiments, detecting the bulk metal content on the surfaces of the plurality of second silicon wafers included in the plurality of second silicon wafer assemblies to obtain multiple bulk metal diffusion results includes:
[0071] For each of the second silicon wafer sets, the bulk metal content on the surface of the plurality of second silicon wafers included in the second silicon wafer set is measured to obtain first measurement data;
[0072] After treating the plurality of second silicon wafers with polyuridine triphosphate, the bulk metal content on the surface of the plurality of second silicon wafers is measured again to obtain second measurement data;
[0073] The bulk metal diffusion results are generated based on the first measurement data and the second measurement data.
[0074] In this embodiment, taking each second silicon wafer set as an example, the multiple second silicon wafers included in the second silicon wafer set are first heated, and the bulk metal content on their surfaces is measured to obtain first measurement data. Specifically, WSPS-ICP-MS can be used to measure the metal content on the silicon wafer surface (by etching the natural oxide layer on the silicon wafer surface). WSPS-ICP-MS is an analytical technique that combines a greenhouse gas (such as volatile organic compounds) collection and sensing system with inductively coupled plasma mass spectrometry (ICP-MS) technology, enabling effective measurement of the bulk metal content on the silicon wafer surface.
[0075] After all the first measurement data are collected, the silicon wafers are processed with polyuridine triphosphate (Poly-UTP) for multiple second silicon wafers, and then the surface of the silicon wafers is measured using WSPS-ICP-MS (the WSPS-ICP-MS equipment etches the polysilicon layer on the surface of the silicon wafers and the shallow surface layer of the silicon wafers, and measures the metals on the surface after etching), thereby obtaining multiple second measurement data.
[0076] Thus, a bulk metal diffusion model is generated based on multiple first measurement data and multiple second measurement data, as Figure 4 shown, Figure 4 which is a schematic diagram of the theoretical model for reducing bulk metal at different temperatures in the embodiments of the present invention. As Figure 4 can be seen, taking bulk metal as Cu, at different temperatures, the diffusion efficiency of bulk metal in silicon wafers with different oxygen contents is different. Thus, according to Figure 4 the temperature shown, a suitable temperature can be selected to process the silicon wafers.
[0077] As Figure 5 shown, Figure 5 is a graph of the relationship between the reduction degree of Bulk Cu before and after heat treatment at a specific temperature. According to the relationship between oxygen content and Bulk Cu, when c < b1, according to the requirements of the subsequent devices for the metal content, combined with the theoretical relationship between temperature and Bulk Cu Diffusion Out Ratio, for silicon wafers that do not meet the metal specifications, a suitable temperature is selected within the temperature range of 60°C to 120°C for heating to achieve the purpose of quickly reducing the Bulk Cu content of the silicon wafers at the lowest cost. In the case where the oxygen content is b1, within the temperature range of 60°C to 120°C, the Bulk Cu Diffusion Out Ratio can reach 0% to 60%. According to the statistical analysis of the test data as Figure 5 shown, for silicon wafers with a Bulk Cu content of 2.5E10, after being heated at a specific temperature for a certain period of time, the Bulk Cu level can be reduced to the 1E10 level.
[0078] According to the relationship between oxygen content and Bulk Cu, when c > a1, according to the requirements of the subsequent devices for the metal content, combined with the theoretical relationship between temperature and Bulk Cu Diffusion Out Ratio, for silicon wafers that do not meet the metal specifications, a suitable temperature is selected within the temperature range of 60°C to 120°C for heating to achieve the purpose of quickly reducing the BulkCu content of the silicon wafers at the lowest cost. In the case where the oxygen content is a1, within the temperature range of 60°C to 120°C, the Bulk Cu Diffusion OutRatio can reach 0% to 80%. According to the statistical analysis of the test data as Figure 5As shown, a silicon wafer with a Bulk Cu content of 1.5E10 can have its Bulk Cu level reduced to 4E9 after being heated to a specific temperature for a certain period of time.
[0079] It should be noted that, based on the experimental data in Table 1, the value range of a1 is 8ppma-10ppma, the value range of c is 10.5ppma-11ppma, and the value range of b1 is 11.5ppma-13ppma.
[0080] oxygen content temperature Bulk metal diffusion output ratio 9ppma 60℃ 0％ 9ppma 80℃ 20％ 9ppma 100℃ 75％ 9ppma 120℃ 80％ 11ppma 60℃ 0％ 11ppma 80℃ 10％ 11ppma 100℃ 55％ 11ppma 120℃ 70％ 12ppma 60℃ 0％ 12ppma 80℃ 3％ 12ppma 100℃ 35％ 12ppma 120℃ 60％
[0081] Table 1
[0082] In some embodiments, the method of heating the silicon wafer to be treated based on the bulk metal diffusion model and the oxygen content corresponding to the silicon wafer to be treated, and then cleaning the heated silicon wafer to remove the bulk metal from the surface of the silicon wafer to be treated, includes:
[0083] Determine the oxygen content corresponding to the silicon wafer to be processed;
[0084] Based on the oxygen content corresponding to the silicon wafer to be processed, the target temperature value of the silicon wafer to be processed is determined by querying the bulk metal diffusion model. The target temperature value is the heating temperature value of the silicon wafer to be processed.
[0085] The silicon wafer to be processed is heated based on the target temperature value, and then the heated silicon wafer is cleaned to remove the bulk metal on the surface of the silicon wafer.
[0086] In this embodiment, when the silicon wafer to be processed needs to be determined, the oxygen content of the silicon wafer is identified, and the optimal target temperature for processing the silicon wafer is determined by querying the bulk metal diffusion model based on the oxygen content. The silicon wafer is then heated according to the target temperature to remove the bulk metal from its surface. That is, when the bulk metal does not meet the metal specification requirements of downstream devices, different heating temperatures can be selected based on the different oxygen contents of the silicon wafer to allow the bulk metal to diffuse to the surface of the silicon wafer. The surface metal is then removed by cleaning, ensuring that the silicon wafer's bulk metal meets the metal specification requirements of downstream devices.
[0087] The present invention provides a method for heating multiple sets of first silicon wafers with different oxygen contents at different temperature values to obtain bulk metal diffusion results for each set of first silicon wafers. Based on these bulk metal diffusion results, a bulk metal diffusion model is generated to indicate the diffusion of bulk metal in the silicon wafers under different oxygen contents and temperature values. Therefore, when processing silicon wafers, the silicon wafers are adaptively heated according to the metal diffusion model and the corresponding oxygen content, and then cleaned after heating, thereby effectively reducing the bulk metal content in the silicon wafers.
[0088] This invention also provides a device for removing bulk metal from a silicon wafer, such as... Figure 6 As shown, it includes:
[0089] The acquisition module 610 is used to acquire multiple sets of first silicon wafers and set multiple temperature values in order of size. The oxygen content of the first silicon wafers included in each set of first silicon wafers is the same, and the oxygen content of the first silicon wafers included in different sets of first silicon wafers is different.
[0090] A heating module is used to generate a bulk metal diffusion model based on the multiple bulk metal precipitation results. The metal diffusion model is used to represent the diffusion of bulk metal in the silicon wafer under different oxygen contents and different temperature values.
[0091] The generation module 630 is used to heat the plurality of first silicon wafer sets sequentially based on each of the plurality of temperature values to obtain a plurality of bulk metal diffusion results. Each bulk metal precipitation result is used to indicate the diffusion of bulk metal on the first silicon wafer at the corresponding oxygen content and temperature value.
[0092] The processing module 640 is used to heat the silicon wafer to be processed based on the bulk metal diffusion model and the oxygen content corresponding to the silicon wafer to be processed, and to clean the heated silicon wafer to be processed to remove the bulk metal on the surface of the silicon wafer to be processed.
[0093] In some embodiments, the generation module 630 includes:
[0094] The processing submodule is used to sequentially heat the plurality of first silicon wafer sets based on each of the plurality of temperature values to obtain a plurality of second silicon wafer sets, wherein each second silicon wafer set includes a plurality of second silicon wafers after the plurality of first silicon wafers have been heat-treated;
[0095] The detection submodule detects the bulk metal content on the surface of the multiple second silicon wafers included in the multiple second silicon wafer sets, and obtains multiple bulk metal diffusion results.
[0096] In some embodiments, the processing submodule includes:
[0097] A cleaning unit is used to clean the plurality of first silicon wafers included in each first silicon wafer set to obtain a plurality of cleaned first silicon wafers.
[0098] A grouping unit is used to sequentially group the multiple first silicon wafers after cleaning based on the multiple temperature values to obtain multiple silicon wafer groups, wherein the multiple silicon wafer groups correspond one-to-one with the multiple temperature values;
[0099] A heating unit is used to heat the plurality of silicon wafer groups respectively at the temperature values corresponding to the silicon wafer groups to obtain the second silicon wafer set.
[0100] In some embodiments, the detection submodule includes:
[0101] The first measurement unit is used to measure the bulk metal content on the surface of the plurality of second silicon wafers included in each second silicon wafer set, and to obtain first measurement data.
[0102] The second measurement unit is used to measure the bulk metal content on the surface of the plurality of second silicon wafers again after treating them with polyurethane triphosphate, and to obtain second measurement data.
[0103] A generation unit is used to generate the plurality of bulk metal diffusion results based on the first measurement data and the second measurement data.
[0104] In some embodiments, the processing module 640 includes:
[0105] The determination submodule is used to determine the oxygen content corresponding to the silicon wafer to be processed;
[0106] The query submodule is used to query the bulk metal diffusion model based on the oxygen content corresponding to the silicon wafer to be processed, and to determine the target temperature value of the silicon wafer to be processed. The target temperature value is the heating temperature value of the silicon wafer to be processed.
[0107] The processing submodule is used to heat the silicon wafer to be processed based on the target temperature value, and to clean the heated silicon wafer to remove the bulk metal on the surface of the silicon wafer.
[0108] In some embodiments, each of the plurality of temperature values is within the range of 60°C to 120°C, and the difference between any two adjacent temperature values is the same.
[0109] The present invention provides a method for heating multiple sets of first silicon wafers with different oxygen contents at different temperature values to obtain bulk metal diffusion results for each set of first silicon wafers. Based on these bulk metal diffusion results, a bulk metal diffusion model is generated to indicate the diffusion of bulk metal in the silicon wafers under different oxygen contents and temperature values. Therefore, when processing silicon wafers, the silicon wafers are adaptively heated according to the metal diffusion model and the corresponding oxygen content, and then cleaned after heating, thereby effectively reducing the bulk metal content in the silicon wafers.
[0110] This invention also provides an electronic device. Please refer to [link to relevant documentation]. Figure 7 The electronic device may include a processor 701, a memory 702, and a program 7021 stored in the memory 702 and capable of running on the processor 701.
[0111] When program 7021 is executed by processor 701, it can achieve the following: Figure 1 Any step in the corresponding method embodiment can achieve the same technical effect, and will not be repeated here to avoid repetition.
[0112] This invention also provides a computer-readable storage medium storing a computer program. When executed by a processor, this computer program implements the various processes of the above-described method for removing bulk metal from a silicon wafer, achieving the same technical effects. To avoid repetition, these processes will not be described again here. The computer-readable storage medium may be a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.
[0113] This invention also provides a computer program product, which is stored in a storage medium and executed by at least one processor to implement the various processes of the above-described method for removing bulk metal from silicon wafers, and achieves the same technical effect. To avoid repetition, it will not be described again here.
[0114] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.
[0115] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk), and includes several instructions to cause a terminal (which may be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in the various embodiments of the present invention.
[0116] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of the present invention.
[0117] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk), and includes several instructions to cause a terminal (which may be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in the various embodiments of the present invention.
[0118] In the various method embodiments of this disclosure, the sequence numbers of each step are not intended to limit the order of the steps. For those skilled in the art, any changes in the order of the steps are within the scope of protection of this disclosure without any creative effort.
[0119] It should be noted that the various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, since the embodiments are basically similar to the product embodiments, the descriptions are relatively simple, and the relevant parts can be referred to the descriptions of the product embodiments.
[0120] The above description represents the preferred embodiments of this disclosure. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles described herein, and these improvements and modifications should also be considered within the scope of protection of this disclosure.
Claims
1. A method for removing bulk metal from a silicon wafer, characterized in that, The method includes: Multiple sets of first silicon wafers are obtained, and multiple temperature values are set in order of size. Each set of first silicon wafers includes multiple first silicon wafers. The oxygen content of the first silicon wafers included in each set of first silicon wafers is the same, while the oxygen content of the first silicon wafers included in different sets of first silicon wafers is different. Based on each of the plurality of temperature values, the plurality of first silicon wafer sets are heated sequentially to obtain a plurality of bulk metal diffusion results. Each bulk metal precipitation result is used to indicate the diffusion of bulk metal on the first silicon wafer at the corresponding oxygen content and temperature value. A bulk metal diffusion model is generated based on the multiple bulk metal precipitation results. The metal diffusion model is used to represent the diffusion of bulk metal in silicon wafers under different oxygen contents and different temperature values. Based on the bulk metal diffusion model and the oxygen content of the silicon wafer to be treated, the silicon wafer to be treated is heated and then cleaned to remove the bulk metal from the surface of the silicon wafer.
2. The method according to claim 1, characterized in that, The process of sequentially heating the plurality of first silicon wafer assemblies based on each of the plurality of temperature values to obtain a plurality of bulk metal diffusion results includes: Based on each of the plurality of temperature values, the plurality of first silicon wafer sets are sequentially heated to obtain a plurality of second silicon wafer sets, wherein each second silicon wafer set includes a plurality of second silicon wafers after the plurality of first silicon wafers have been heated; The bulk metal content on the surface of the multiple second silicon wafers included in the multiple second silicon wafer sets is detected to obtain multiple bulk metal diffusion results.
3. The method according to claim 2, characterized in that, The step of sequentially heating the plurality of first silicon wafer sets based on each of the plurality of temperature values to obtain a plurality of second silicon wafer sets includes: For each set of first silicon wafers, the plurality of first silicon wafers included in each set of first silicon wafers are cleaned to obtain a plurality of cleaned first silicon wafers; Based on the plurality of temperature values, the multiple first silicon wafers after cleaning are grouped to obtain multiple silicon wafer groups, and the multiple silicon wafer groups correspond one-to-one with the plurality of temperature values; The multiple silicon wafer groups are heated according to the temperature values corresponding to the silicon wafer groups to obtain the second silicon wafer set.
4. The method according to claim 3, characterized in that, The step of detecting the bulk metal content on the surfaces of the multiple second silicon wafers included in the plurality of second silicon wafer sets to obtain multiple bulk metal diffusion results includes: For each of the second silicon wafer sets, the bulk metal content on the surface of the plurality of second silicon wafers included in the second silicon wafer set is measured to obtain first measurement data; After treating the plurality of second silicon wafers with polyuridine triphosphate, the bulk metal content on the surface of the plurality of second silicon wafers is measured again to obtain second measurement data; The bulk metal diffusion results are generated based on the first measurement data and the second measurement data.
5. The method according to claim 1, characterized in that, The process of heating the silicon wafer to be treated based on the bulk metal diffusion model and the oxygen content corresponding to the silicon wafer to be treated, and then cleaning the heated silicon wafer to remove the bulk metal from the surface of the silicon wafer to be treated, includes: Determine the oxygen content corresponding to the silicon wafer to be processed; Based on the oxygen content corresponding to the silicon wafer to be processed, the target temperature value of the silicon wafer to be processed is determined by querying the bulk metal diffusion model. The target temperature value is the heating temperature value of the silicon wafer to be processed. The silicon wafer to be processed is heated based on the target temperature value, and then the heated silicon wafer is cleaned to remove the bulk metal on the surface of the silicon wafer.
6. The method according to any one of claims 1-5, characterized in that, Each of the plurality of temperature values is within the range of 60℃ to 120℃, and the difference between any two adjacent temperature values is the same.
7. A device for removing bulk metal from a silicon wafer, characterized in that, The device includes: The acquisition module is used to acquire multiple sets of first silicon wafers and set multiple temperature values in order of size. The oxygen content of the first silicon wafers included in each set of first silicon wafers is the same, and the oxygen content of the first silicon wafers included in different sets of first silicon wafers is different. A heating module is used to sequentially heat the plurality of first silicon wafer sets based on each of the plurality of temperature values to obtain a plurality of bulk metal diffusion results. Each bulk metal precipitation result is used to indicate the diffusion of bulk metal on the first silicon wafer at the corresponding oxygen content and temperature value. A generation module is used to generate a bulk metal diffusion model based on the multiple bulk metal precipitation results. The metal diffusion model is used to represent the diffusion of bulk metals in a silicon wafer under different oxygen contents and different temperature values. The processing module is used to heat the silicon wafer to be processed based on the bulk metal diffusion model and the oxygen content corresponding to the silicon wafer to be processed, and to clean the heated silicon wafer to remove the bulk metal on the surface of the silicon wafer to be processed.
8. An electronic device, characterized in that, include: A processor, a memory, and a program stored in the memory and executable on the processor, wherein the program, when executed by the processor, implements the steps of the method as described in any one of claims 1 to 6.
9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the steps of the method as described in any one of claims 1 to 6.
10. A computer program product, characterized in that, Includes computer instructions that, when executed by a processor, implement the steps of the method as described in any one of claims 1 to 6.