Method for removing tocs from a semiconductor grade hydrogen peroxide solution by means of a cascade
Patent Information
- Application Number
- CN202611178050.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-08-05
- Publication Date
- 2026-09-25
AI Technical Summary
在纯化过程中对有机物杂质的去除尤为重要，过氧化氢中有机物杂质过高，不仅影响离子交换树脂去除阴阳离子的效果，更重要的是有机物杂质在蚀刻和清洗过程中会沾污线路板，使其导电性下降甚至断路
本发明采用TOC脱除柱去除大部分的TOC，随后通过螯合树脂柱截留各类高价过渡重金属，通过阳离子交换树脂深度脱除钠、钾一价碱金属，通过阴离子交换树脂去除磷酸根、卤素与有机阴离子，三者串联协同可脱除体系中各类杂质，而后再利用氨基化聚四氟乙烯粒料柱脱除剩余的TOC，使得所制产品TOC≤ 1ppm。
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Figure CN122806304A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of semiconductor-grade hydrogen peroxide solution technology, specifically a method for the stepwise removal of TOC from semiconductor-grade hydrogen peroxide solution. Background Technology
[0002] Conductor-grade hydrogen peroxide aqueous solution is an ultra-clean, high-purity electronic chemical used in semiconductor processes, primarily for oxidation and cleaning of silicon wafers. Its purity and cleanliness have a significant impact on yield, electrical performance, and reliability. The preparation of semiconductor-grade hydrogen peroxide aqueous solution involves using industrial-grade hydrogen peroxide aqueous solution as raw material, removing impurities from the industrial-grade product, and purifying it to prepare a high-quality semiconductor-grade hydrogen peroxide aqueous solution. The removal of organic impurities is particularly important during the purification process. Excessive organic impurities in the hydrogen peroxide not only affect the effectiveness of ion exchange resins in removing anions and cations, but more importantly, these organic impurities can contaminate circuit boards during etching and cleaning, reducing conductivity and even causing open circuits.
[0003] Existing technologies, such as chelating resins and cation / anion exchange resins, can remove most impurities from hydrogen peroxide through adsorption and filtration. However, with the continuous development of the semiconductor industry, the requirements for the organic impurity content in semiconductor-grade hydrogen peroxide solutions are becoming increasingly stringent. Some specialized industries require organic impurity content to be less than 1 ppm, but traditional tandem resin adsorption column methods cannot reliably achieve this goal. Therefore, a stepwise method for removing TOC from semiconductor-grade hydrogen peroxide solutions is proposed. Summary of the Invention
[0004] To address the shortcomings of existing technologies, this invention provides a stepwise method for removing TOC from semiconductor-grade hydrogen peroxide solutions. The method employs a TOC removal column to remove most of the TOC, followed by the synergistic use of chelating resins, cation and anion exchange resins to remove various impurities from the system. Finally, an aminated polytetrafluoroethylene (PTFE) granule column is used to remove the remaining TOC, further improving the purity of the hydrogen peroxide solution.
[0005] To achieve the above objectives, the present invention provides the following technical solution: a method for stepwise removal of TOC from semiconductor-grade hydrogen peroxide solution, comprising the following steps: (1) The raw material solution is filtered through a reverse osmosis membrane filtration device and then enters a TOC removal column to initially remove TOC and obtain a primary hydrogen peroxide solution; (2) The primary hydrogen peroxide solution is then passed sequentially through a chelating resin column, a cation exchange resin column, and an anion exchange resin column to obtain a secondary hydrogen peroxide solution; (3) The intermediate hydrogen peroxide solution is then passed through an aminated polytetrafluoroethylene granule column and an end membrane filtration device to obtain a high-purity hydrogen peroxide solution.
[0006] Preferably, in step (1), the pore size of the filter membrane in the reverse osmosis membrane filtration device is ≤ 1nm.
[0007] Preferably, in step (1), the filler in the TOC removal column is resin D4006.
[0008] Preferably, in step (2), the packing material in the chelating resin column is aminophosphonic acid chelating resin; the packing material in the cation exchange resin column is resin 1200Na; and the packing material in the anion exchange resin column is resin IRA900. Industrial hydrogen peroxide solution contains both cation and anion impurities, and a single cation / anion resin cannot meet the standards; 1200Na removes metal cations, and IRA900 removes phosphate and organic anions. The two are connected in series and complement each other, simultaneously reducing the total content of cations and anions, thus meeting the stringent requirement of low content of metal ions and anions in semiconductor-grade high-purity hydrogen peroxide solution.
[0009] Preferably, in step (3), the pore size of the filter membrane in the end membrane filtration device is 20 nm.
[0010] Preferably, in step (3), the preparation method of the aminated polytetrafluoroethylene granules is as follows: S1, the polytetrafluoroethylene granules are washed with ultrapure water and dried to obtain pretreated granules; S2, the pretreated granules are placed in a plasma treatment device, the vacuum is ≤ 2pa, and nitrogen and hydrogen are used as gas sources for plasma treatment. After the treatment is completed, nitrogen is used to purge for 15-20 minutes to obtain modified granules; S3, the modified granules are then purified to obtain aminated polytetrafluoroethylene granules.
[0011] Preferably, in step S2, the flow rate of nitrogen is 0.5-0.6 L / min and the flow rate of hydrogen is 1-1.2 L / min.
[0012] Preferably, in step S2, the plasma treatment is performed at a discharge power of 90-100W for 8-10 minutes.
[0013] Preferably, in step S3, the purification process involves first keeping the sample at 90-100°C under vacuum for 30-40 minutes, then dynamically soaking it in ultrapure water for 30-35 hours, and finally drying and sieving.
[0014] Preferably, in steps (1)-(3), the flow rate in the TOC removal column is 3 BV / h; the flow rate in the chelating resin column is 5 BV / h; the flow rate in the cation exchange resin column is 10 BV / h; the flow rate in the anion exchange resin column is 10 BV / h; and the flow rate in the aminated polytetrafluoroethylene granule column is 4 BV / h.
[0015] This invention provides a method for the stepwise removal of TOC from semiconductor-grade hydrogen peroxide solutions, which has the following advantages compared with existing technologies: This invention employs a TOC removal column to remove most of the TOC, followed by the retention of various high-valence transition heavy metals through a chelating resin column, the deep removal of sodium and potassium monovalent alkali metals through a cation exchange resin, and the removal of phosphate, halogens, and organic anions through anion exchange resin. These three processes work synergistically to remove various impurities from the system. Finally, an aminated polytetrafluoroethylene granule column is used to remove the remaining TOC, resulting in a product with a TOC ≤ 1 ppm.
[0016] This invention grafts amino groups onto polytetrafluoroethylene (PTFE) granules via plasma treatment to capture residual trace amounts of TOC in the adsorbed product, thereby improving the purity of the hydrogen peroxide solution. After grafting, vacuum insulation is used to drive surface free radical rearrangement to form stable amino groups, removing volatile byproducts and reducing amino group attenuation. Dynamic circulation immersion in ultrapure water washes away nitrogen-containing fragments, sputtered metals, and air-adsorbed impurities, preventing contamination of the hydrogen peroxide solution and affecting its purity. Attached Figure Description
[0017] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a diagram of the high-purity hydrogen peroxide solution preparation system of the present invention; Figure 2 These are morphological images of polytetrafluoroethylene granules and aminated polytetrafluoroethylene granules in Example 2 of the present invention.
[0018] In the picture: 1-Reverse osmosis membrane filtration device, 2-TOC removal column, 3-chelating resin column, 4-cation exchange resin column, 5-anion exchange resin column, 6-aminated polytetrafluoroethylene granular column, 7-terminal membrane filtration device, 8-cooler. Detailed Implementation
[0019] The following embodiments are provided to illustrate the implementation of this application in detail, so that the process of how this application uses technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.
[0020] Example 1
[0021] A stepwise TOC removal system for semiconductor-grade hydrogen peroxide solution includes a reverse osmosis membrane filtration unit 1, a TOC removal column 2, a chelating resin column 3, a cation exchange resin column 4, an anion exchange resin column 5, an aminated polytetrafluoroethylene (PTFE) granule column 6, an end-membrane filtration unit 7, and two sets of coolers 8. One set of coolers 8 is located between the reverse osmosis membrane filtration unit 1 and the TOC removal column 2, and the other set of coolers 8 is located between the chelating resin column 3 and the cation exchange resin column 4. The production temperature can be controlled between 5-20°C using the coolers 8.
[0022] Example 2
[0023] The preparation method of aminated polytetrafluoroethylene granules is as follows: S1. Polytetrafluoroethylene granules (0.4mm±0.1mm) are washed with ultrapure water and dried to obtain pretreated granules; S2. Place the pretreated granules in a plasma treatment device, evacuate to a vacuum of ≤ 2pa, use nitrogen (0.5L / min) and hydrogen (1L / min) as gas sources, treat for 8.5min at a discharge power of 95W, and after treatment, purge with nitrogen for 18min to obtain modified granules. S3. Subsequently, the modified granules were first kept at 95°C under vacuum for 36 minutes, then dynamically soaked in ultrapure water for 32 hours, and finally dried and sieved to obtain aminated polytetrafluoroethylene granules.
[0024] Example 3
[0025] The preparation method of aminated polytetrafluoroethylene granules is as follows: S1. Polytetrafluoroethylene granules (0.4mm±0.1mm) are washed with ultrapure water and dried to obtain pretreated granules; S2. Place the pretreated granules in a plasma treatment device, evacuate to a vacuum of ≤ 2pa, use nitrogen (0.6L / min) and hydrogen (1L / min) as gas sources, treat for 8min at a discharge power of 100W, and after treatment, purge with nitrogen for 20min to obtain modified granules. S3. Subsequently, the modified granules were first kept at 90°C under vacuum for 40 minutes, then dynamically soaked in ultrapure water for 30 hours, and finally dried and sieved to obtain aminated polytetrafluoroethylene granules.
[0026] Example 4
[0027] The preparation method of aminated polytetrafluoroethylene granules is as follows: S1. Polytetrafluoroethylene granules (0.4mm±0.1mm) are washed with ultrapure water and dried to obtain pretreated granules; S2. Place the pretreated granules in a plasma treatment device, evacuate to a vacuum of ≤ 2pa, use nitrogen (0.5L / min) and hydrogen (1.2L / min) as gas sources, treat for 10min at a discharge power of 90W, and after treatment, purge with nitrogen for 15min to obtain modified granules. S3. Subsequently, the modified granules were first kept at 100°C under vacuum for 30 minutes, then dynamically soaked in ultrapure water for 35 hours, and finally dried and sieved to obtain aminated polytetrafluoroethylene granules.
[0028] Example 5
[0029] A method for stepwise removal of TOC from semiconductor-grade hydrogen peroxide solution, using the aminated polytetrafluoroethylene granules from Example 2, includes the following steps: (1) The raw material solution is filtered through a reverse osmosis membrane filtration device (membrane pore size ≤ 1nm) and then enters a TOC removal column (resin D4006, flow rate 3BV / h) to initially remove TOC and obtain a primary hydrogen peroxide solution (TOC ≤ 20ppm). (2) The primary hydrogen peroxide solution was then passed sequentially through a chelating resin column (aminophosphonic acid chelating resin, flow rate of 5 BV / h), a cation exchange resin column (resin 1200Na, flow rate of 10 BV / h), and an anion exchange resin column (resin IRA900, flow rate of 10 BV / h) to obtain a secondary hydrogen peroxide solution. (3) The intermediate hydrogen peroxide solution is then passed through an aminated polytetrafluoroethylene granule column (flow rate of 4 BV / h) and an end membrane filtration device (filter membrane pore size of 20 nm) to obtain a high-purity hydrogen peroxide solution.
[0030] Example 6
[0031] A method for stepwise removal of TOC from semiconductor-grade hydrogen peroxide solution, using the aminated polytetrafluoroethylene granules from Example 3, with the remainder being the same as in Example 5.
[0032] Example 7
[0033] A method for stepwise removal of TOC from semiconductor-grade hydrogen peroxide solution, using the aminated polytetrafluoroethylene granules from Example 4, with the remainder being the same as in Example 5.
[0034] Comparative Example 1 A method for stepwise removal of TOC from semiconductor-grade hydrogen peroxide solution is basically the same as that in Example 5, except that the aminated polytetrafluoroethylene granules are replaced with aminated polytetrafluoroethylene granules-A.
[0035] The preparation method of aminated polytetrafluoroethylene granules-A is as follows: S1. Polytetrafluoroethylene granules (0.4mm±0.1mm) are washed with ultrapure water and dried to obtain pretreated granules; S2. Place the pretreated granules in a plasma treatment device, evacuate to a vacuum of ≤ 2pa, use nitrogen (0.5L / min) and hydrogen (1L / min) as gas sources, treat for 8.5min at a discharge power of 95W, and after treatment, purge with nitrogen for 18min to obtain modified granules. S3. The modified granules were dynamically soaked in ultrapure water for 32 hours, and then dried and sieved to obtain aminated polytetrafluoroethylene granules-A.
[0036] Comparative Example 2 A method for stepwise removal of TOC from semiconductor-grade hydrogen peroxide solution is basically the same as that in Example 5, except that the aminated polytetrafluoroethylene granules are replaced with aminated polytetrafluoroethylene granules-B.
[0037] The preparation method of aminated polytetrafluoroethylene granules-B is as follows: S1. Polytetrafluoroethylene granules (0.4mm±0.1mm) are washed with ultrapure water and dried to obtain pretreated granules; S2. Place the pretreated granules in a plasma treatment device, evacuate to a vacuum of ≤ 2pa, use nitrogen (0.5L / min) and hydrogen (1L / min) as gas sources, treat for 8.5min at a discharge power of 95W, and after treatment, purge with nitrogen for 18min to obtain modified granules. S3. Subsequently, the modified granules were kept at 95°C under vacuum for 36 minutes, and then dried and sieved to obtain aminated polytetrafluoroethylene granules-B.
[0038] Comparative Example 3 A method for stepwise removal of TOC from semiconductor-grade hydrogen peroxide solution, using the aminated polytetrafluoroethylene granules from Example 2, includes the following steps: (1) The raw material solution is filtered through a reverse osmosis membrane filtration device (membrane pore size ≤ 1nm) to obtain a primary hydrogen peroxide solution; Steps (2)-(3) are the same as in Example 5.
[0039] Comparative Example 4 A method for stepwise removal of TOC from semiconductor-grade hydrogen peroxide solution includes the following steps: Steps (1)-(2) are the same as in Example 5; (3) The intermediate hydrogen peroxide solution is then filtered through an end-of-line membrane filtration device (membrane pore size 20nm) to obtain a high-purity hydrogen peroxide solution.
[0040] Comparative Example 5 A method for stepwise removal of TOC from semiconductor-grade hydrogen peroxide solution, using the aminated polytetrafluoroethylene granules from Example 2, includes the following steps: (1) The raw material solution is filtered through a reverse osmosis membrane filtration device (membrane pore size ≤ 1nm) to obtain a primary hydrogen peroxide solution; (2) The primary hydrogen peroxide solution is then passed sequentially through several sets (1-4 sets) of aminated polytetrafluoroethylene granule columns connected in series (flow rate of 4 BV / h) and an end membrane filtration device (filter membrane pore size of 20 nm) to obtain a high-purity hydrogen peroxide solution.
[0041] Table 1. Number of series connections and TOC content in hydrogen peroxide solution
[0042] As shown in Table 1, although the TOC in the hydrogen peroxide solution can be ≤ 1ppm by connecting four sets of aminated polytetrafluoroethylene granule columns in series, the removal effect on potassium and sodium is relatively poor. Moreover, under the strong oxidizing environment of hydrogen peroxide, the amino group is gradually oxidized into nitro group with no adsorption activity. Regeneration can only wash away impurities and cannot reduce the amino group, which greatly shortens the cycle life and increases the cost.
[0043] Quality Inspection 1. The high-purity hydrogen peroxide solutions in Example 5 and Comparative Examples 1-4 were tested. The specific test results are shown in Table 2.
[0044] Table 2 Test Results
[0045] Table 2 shows that compared with Example 5, the amino-tetrafluoroethylene granules-A in Comparative Example 1 did not undergo vacuum insulation treatment, and the amino-tetrafluoroethylene granules-B in Comparative Example 2 did not undergo dynamic soaking in ultrapure water, resulting in an increase in the TOC content of the product. Comparative Example 3 did not use a TOC removal column to remove a large amount of TOC in advance, resulting in a higher TOC content in the final product. Comparative Example 4 did not use an amino-tetrafluoroethylene granule column, and its product had the highest TOC content. The combination of Example 5 and Comparative Examples 3-4 indicates that the amino-tetrafluoroethylene granule column has a good removal effect on small amounts of TOC in hydrogen peroxide solution. However, its removal effect is limited when dealing with large amounts of TOC. But by using other adsorption columns in advance, the TOC content in the product can be significantly reduced to ≤ 1 ppm, achieving high purification of the hydrogen peroxide solution.
[0046] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A method for stepwise removal of TOC from semiconductor-grade hydrogen peroxide solution, characterized in that, Includes the following steps: (1) The raw material solution is filtered through a reverse osmosis membrane filtration device and then enters a TOC removal column to initially remove TOC and obtain a primary hydrogen peroxide solution; (2) The primary hydrogen peroxide solution is then passed sequentially through a chelating resin column, a cation exchange resin column, and an anion exchange resin column to obtain a secondary hydrogen peroxide solution; (3) The intermediate hydrogen peroxide solution is then passed through an aminated polytetrafluoroethylene granule column and an end membrane filtration device to obtain a high-purity hydrogen peroxide solution.
2. The method for step-by-step removal of TOC from semiconductor-grade hydrogen peroxide solution according to claim 1, characterized in that, In step (1), the pore size of the filter membrane in the reverse osmosis membrane filtration device is ≤ 1nm.
3. The method for step-by-step removal of TOC from semiconductor-grade hydrogen peroxide solution according to claim 1, characterized in that, In step (1), the filler in the TOC removal column is resin D4006.
4. The method for step-by-step removal of TOC from semiconductor-grade hydrogen peroxide solution according to claim 1, characterized in that, In step (2), the packing material in the chelating resin column is aminophosphonic acid chelating resin; the packing material in the cation exchange resin column is resin 1200Na; and the packing material in the anion exchange resin column is resin IRA900.
5. The method for stepwise removal of TOC from semiconductor-grade hydrogen peroxide solution according to claim 1, characterized in that, In step (3), the pore size of the filter membrane in the end membrane filtration device is 20 nm.
6. The method for step-by-step removal of TOC from semiconductor-grade hydrogen peroxide solution according to claim 1, characterized in that, In step (3), the preparation method of the aminated polytetrafluoroethylene granules is as follows: S1. The polytetrafluoroethylene granules are washed with ultrapure water and dried to obtain pretreated granules. S2. Place the pretreated granules in a plasma treatment device, evacuate to a vacuum of ≤ 2pa, and use nitrogen and hydrogen as gas sources for plasma treatment. After the treatment is completed, purge with nitrogen for 15-20 minutes to obtain modified granules. S3. Subsequently, the modified granules were purified to obtain aminated polytetrafluoroethylene granules.
7. The method for step-by-step removal of TOC from semiconductor-grade hydrogen peroxide solution according to claim 6, characterized in that, In step S2, the flow rate of nitrogen is 0.5-0.6 L / min, and the flow rate of hydrogen is 1-1.2 L / min.
8. The method for step-by-step removal of TOC from semiconductor-grade hydrogen peroxide solution according to claim 6, characterized in that, In step S2, the plasma treatment is performed at a discharge power of 90-100W for 8-10 minutes.
9. The method for stepwise removal of TOC from semiconductor-grade hydrogen peroxide solution according to claim 6, characterized in that, In step S3, the purification process involves first keeping the sample at 90-100℃ under vacuum for 30-40 minutes, then dynamically soaking it in ultrapure water for 30-35 hours, and finally drying and sieving.
10. The method for stepwise removal of TOC from semiconductor-grade hydrogen peroxide solution according to claim 1, characterized in that, In steps (1)-(3), the flow rate in the TOC removal column is 3 BV / h; the flow rate in the chelating resin column is 5 BV / h; the flow rate in the cation exchange resin column is 10 BV / h; the flow rate in the anion exchange resin column is 10 BV / h; and the flow rate in the aminated polytetrafluoroethylene granule column is 4 BV / h.