Method for preserving an article and system for preserving an article

Abstract

This disclosure provides a method and system for preserving a product, belonging to the field of semiconductor technology. The preservation method is used to preserve a product after low-temperature halogen etching. The method includes: placing the product in a preservation tank containing a flowing cleaning solution, immersing the product in the cleaning solution with the etched surface of the product facing the flow direction of the cleaning solution. This disclosure can slow down the corrosion of the product.

Description

Technical Field

[0001] This disclosure belongs to the field of semiconductor technology, and particularly relates to a method for storing articles and a system for storing articles. Background Technology

[0002] In the manufacturing process of light-emitting diodes (LEDs), low-temperature halogen plasma etching is a key step in achieving fine pattern transfer. After the etching process is completed, due to the continuous operation of the equipment in a mass production environment (the current product has finished etching while the previous batch of products may still be undergoing the resist removal and cleaning process) and the time required for the transfer of products from the etching process to the resist removal and cleaning process, the products cannot immediately enter the resist removal and cleaning process after etching, but must undergo a storage period.

[0003] In related technologies, the storage of etched products mainly employs two types of preservation methods: dry and wet. Dry preservation typically uses equipment such as nitrogen cabinets or clean boxes with low relative humidity (<10%) to store the products for a short period in a low-humidity, clean environment. Wet preservation involves statically immersing the products in deionized water or other inert liquids, isolating them from air through the liquid phase to delay direct contact between byproducts and oxygen.

[0004] However, in a dry storage environment, byproducts such as gallium halide, aluminum halide, and halogen-containing photoresist polymers generated during etching cannot be effectively treated. These byproducts undergo hydrolysis upon contact with moisture in the air, generating strong acidic substances that continuously corrode the PN junction and heterojunction interface, leading to irreversible failures such as device leakage and breakdown. While static immersion can isolate the device from air, the acidic byproducts generated during immersion accumulate on the etched surface, causing localized corrosion. Summary of the Invention

[0005] This disclosure provides a method and system for preserving a product, which can slow down corrosion of the product. The technical solution is as follows: This disclosure provides a method for preserving a product after low-temperature halogen etching. The preservation method includes: The product is placed in a storage tank containing a flowing cleaning solution, the product is immersed in the cleaning solution, and the etched surface of the product faces the flow direction of the cleaning solution.

[0006] In another implementation of this disclosure, the temperature of the cleaning fluid is 18°C ​​to 25°C.

[0007] In another implementation of this disclosure, the flow rate of the cleaning fluid is 0.2 m / s to 1.5 m / s.

[0008] In another implementation of this disclosure, the resistivity of the cleaning fluid is greater than or equal to 18.2 MΩ. cm.

[0009] In another implementation of this disclosure, the pH of the cleaning solution is 6.5 to 7.5.

[0010] In another implementation of this disclosure, the step of placing the article in a storage slot for storage includes: The product is fixed in the storage tank by a wafer carrier; the cleaning solution is continuously introduced from the inlet end of the storage tank and continuously discharged from the outlet end of the storage tank, so that the cleaning solution flows in a directional manner.

[0011] In another implementation of this disclosure, the discharge flow rate of the cleaning fluid discharged from the drain end is 20% to 30% of the inlet flow rate of the cleaning fluid entering from the inlet end.

[0012] In another implementation of this disclosure, after the product is placed in the storage tank, the storage method further includes: detecting the concentration of halide ions in the cleaning solution, and increasing the flow rate of the cleaning solution when the concentration of halide ions in the cleaning solution is higher than 10 ppb.

[0013] In another implementation of this disclosure, the cleaning solution is deionized water, anhydrous ethanol, or anhydrous isopropanol.

[0014] On the other hand, this disclosure also provides a preservation system for an article of manufacture, the preservation system comprising: A storage tank containing a flowing cleaning solution is used to store a product, wherein the product is immersed in the cleaning solution during storage, and the etched surface of the product faces the flow direction of the cleaning solution.

[0015] The beneficial effects of the technical solutions provided in this disclosure are: When the article is preserved using the preservation method provided in this embodiment, the method involves immersing the article in a preservation tank containing a flowing cleaning solution. The etched surface of the article faces the flow direction of the cleaning solution. This arrangement ensures that the article is always immersed in the flowing cleaning solution, thereby removing acidic substances generated from the hydrolysis of byproducts on the article's surface and preventing localized acid accumulation that could corrode the article. Compared to static wet immersion, this preservation method helps prevent byproducts from depositing in micro-areas on the etched surface of the article, reducing corrosion. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this disclosure, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a flowchart of a method for preserving an article provided in an embodiment of this disclosure; Figure 2 This is a schematic diagram of the product being placed in the storage tank; Figure 3 This is a flowchart of another method for preserving an article provided in this disclosure. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this disclosure clearer, the embodiments of this disclosure will be described in further detail below with reference to the accompanying drawings.

[0019] This disclosure provides a method for preserving a product after low-temperature halogen etching.

[0020] Low-temperature halogen etching is a semiconductor micro-nano fabrication technology. Simply put, it is a high-precision, low-damage patterning process for semiconductor materials using active gases / plasma containing halogen elements (such as chlorine and bromine) at relatively low temperatures (usually -20°C).

[0021] In this embodiment, the product is an AlGaInP product. In other examples, the product may also be a GaN product.

[0022] After being excited into plasma, halogen gases undergo a violent chemical reaction with AlGaInP materials to generate volatile metal halides (such as GaCl3, AlCl3, InCl3, etc.).

[0023] The reason for choosing halogen etching is that the products (AlCl3, GaCl3, etc.) generated by the reaction of aluminum (Al), gallium (Ga), and indium (In) in AlGaInP with chlorine and bromine have high volatility and can be easily removed by the vacuum system during the reaction, thus achieving continuous and clean etching.

[0024] The purpose of etching is to precisely and controllably transfer the pattern on the photoresist mask onto the underlying AlGaInP material.

[0025] After etching, the surface of the artifact has numerous fine mesas, trenches, or holes (used to define electrode areas or achieve current limiting). These structures have very steep sidewalls and contain dangling bonds and damage layers. After etching, the artifact surface is still covered with a layer of photoresist used for the etching mask. At this point, the photoresist has not yet been removed.

[0026] Figure 1 For a flowchart of the method for preserving the article provided in the embodiments of this disclosure, please refer to [link / reference]. Figure 1 The methods for saving include: S101: Immerse the product in a storage tank for preservation.

[0027] The storage tank contains flowing cleaning fluid, and the etched surface of the workpiece faces the direction of the cleaning fluid flow.

[0028] Figure 2 This is a diagram showing the product placed in the storage tank, such as... Figure 2 As shown, the etched surface a of the product faces the flow direction b of the cleaning fluid, meaning that the etched surface a has no structural obstruction and is directly exposed to the flow direction b of the cleaning fluid. The cleaning fluid directly washes and flows over the etched surface a.

[0029] When the article is preserved using the preservation method provided in this embodiment, the method involves immersing the article in a preservation tank containing a flowing cleaning solution. The etched surface of the article faces the flow direction of the cleaning solution. This arrangement ensures that the article is always immersed in the flowing cleaning solution, thereby removing acidic substances generated from the hydrolysis of byproducts on the article's surface and preventing localized acid accumulation that could corrode the article. Compared to static wet immersion, this preservation method helps prevent byproducts from depositing in micro-areas on the etched surface of the article, reducing corrosion.

[0030] This disclosure also provides another method for preserving articles, such as... Figure 3 As shown, the saving methods include: S301: Products containing AlGaInP.

[0031] In this embodiment, the AlGaInP product has completed pattern transfer through low-temperature halogen etching, but the surface of the product still has photoresist.

[0032] Among them, AlGaInP products can be AlGaInP-based red / yellow light-emitting diode chips after etching.

[0033] S302: Immerse the product in a storage tank for preservation.

[0034] After etching is complete, the product is removed within 10 minutes in a Class 100 clean environment and immediately placed in a storage tank containing a flowing cleaning solution.

[0035] The product is immersed in the cleaning solution with the etched surface facing the direction of the cleaning solution flow. This prevents the etched surface of the product from being exposed to air for a long time.

[0036] In this embodiment, the cleaning solution is deionized water.

[0037] In the above implementation method, deionized water is used as the cleaning solution. Its core advantages lie in its high purity and chemical inertness. It can effectively dissolve and remove the acid and metal ions generated by the hydrolysis of etching byproducts without introducing additional active substances. Compared with organic solvents or acid / alkali solutions, deionized water will not undergo uncontrollable reactions with the photoresist (such as swelling, stripping, or excessive cross-linking) and will not cause chemical erosion to the AlGaInP interface, making it a gentle medium.

[0038] In another example, the cleaning solution may also be anhydrous isopropanol or anhydrous ethanol.

[0039] For water-sensitive ultrathin AlGaInP barrier layer devices, anhydrous isopropanol or anhydrous ethanol can be used as the flowing rinsing medium. At the same time, nitrogen is used to seal the entire process to prevent water vapor from entering, so as to achieve damage-free storage in an anhydrous environment.

[0040] Among them, water-sensitive ultrathin AlGaInP barrier layer devices can be found in AlGaInP-light-emitting diode chips. In these chips, the barrier layer is typically an AlGaInP layer with a high Al content and a thickness of 5-15 nm, much smaller than that of conventional barrier layers. Moisture can easily penetrate it, and water sensitivity increases exponentially compared to conventional methods.

[0041] Optionally, the temperature inside the storage tank is 18℃~25℃.

[0042] In the above implementation, after the product is etched, the byproducts of the etching (AlCl3, GaCl3, etc.) will rapidly hydrolyze upon contact with water to generate strong acid (HCl), which will corrode the etched structure of the product.

[0043] Hydrolysis is an exothermic reaction and is temperature-sensitive. During hydrolysis, the hydrolysis rate typically increases by 2 to 4 times for every 10°C increase in ambient temperature. Setting the temperature in the storage tank within the above range (i.e., room temperature) avoids both excessively slow hydrolysis at low temperatures (e.g., <10°C) leading to difficulties in subsequent cleaning and rapidly accelerated hydrolysis at high temperatures (e.g., >30°C), which could instantly generate large amounts of acid that corrode the products.

[0044] Within this temperature range, the acid produced by the hydrolysis reaction can be carried away by the flowing cleaning fluid in a timely manner rather than accumulating locally, reducing the possibility of corrosion.

[0045] For example, the temperature inside the storage tank is 20°C or 22°C, etc.

[0046] Optionally, the flow rate of the cleaning fluid in the storage tank is 0.2 m / s to 1.5 m / s.

[0047] In the above implementation, the flow rate of the cleaning solution in the storage tank is 0.2m / s to 1.5m / s. This ensures that the cleaning solution in the storage tank flows at the above speed, so that the acid and dissolution products generated by the by-products of the product during the hydrolysis process can be quickly carried away after etching, preventing local enrichment corrosion.

[0048] At the same time, it can avoid excessive flow rate causing shear damage to the fine etched structure, thus ensuring that the ejected particles do not fall back onto the product surface but are carried away while protecting the integrity of the device. Moreover, the gentle flushing force will not damage the product structure.

[0049] In this embodiment, the flow rate of the cleaning fluid in the storage tank is 0.8 or 1.0 m / s.

[0050] Optionally, the resistivity of the cleaning fluid in the storage tank is ≥18.2 MΩ. cm.

[0051] In the above implementation, the surface of the etched product contains various metal halides (AlCl3, GaCl3, etc.) and exposed semiconductor heterojunction interfaces. If the cleaning solution contains trace amounts of ions, these ions will form a micro-battery effect between different metal / semiconductor regions, accelerating localized corrosion.

[0052] The resistivity of the cleaning fluid in the storage tank is ≥18.2 MΩ. The cm ensures that the cleaning solution contains almost no free ions, preventing the formation of conductive circuits and fundamentally inhibiting electrochemical corrosion.

[0053] In other words, using a cleaning solution with a resistivity ≥18.2 MΩ·cm to dynamically rinse and store the work-in-process completely eliminates metal ion contamination from the perspective of liquid chemical purity, avoids electrochemical corrosion and ion catalytic side reactions, and provides a clean temporary storage environment for AlGaInP etched products before resist removal.

[0054] Optionally, the pH of the cleaning solution in the storage tank is 6.5 to 7.5.

[0055] In the above implementation method, the pH value of the liquid in the storage tank is controlled at 6.5~7.5 (i.e., neutral range). Its core advantage is to suppress the hydrolysis reaction rate of metal halides to the maximum extent, while avoiding additional damage to the semiconductor interface and photoresist by acid or alkali.

[0056] When the pH is too low (<6.5), the acidic environment will directly erode the aluminum-rich layer and heterojunction interface in AlGaInP, leading to irreversible leakage current channels.

[0057] When the pH is too high (>7.5), OH - Will with Al 3+ Ga 3+ When metal ions react, they form hydroxide precipitates. These precipitates adhere to the etched sidewalls and the photoresist surface, and are extremely difficult to remove subsequently, potentially blocking the microstructure.

[0058] Therefore, maintaining a neutral pH of 6.5–7.5 ensures that trace amounts of H+ generated during hydrolysis are contained within the pH range during dynamic rinsing. + The solution in the tank is carried away by the overflow in time, and always maintains a non-corrosive neutral environment. At the same time, the metal ions exist in a dissolved state rather than a precipitated state and are discharged with the overflow without remaining on the surface of the product. Moreover, the photoresist remains stable under weak alkaline or weak acidic conditions and will not undergo premature cross-linking, softening or peeling.

[0059] For example, the pH of the cleaning solution in the storage tank is 7.0, 7.1, etc.

[0060] Optionally, step S302 can be implemented in the following way: 3021: The product is fixed in the storage tank by a wafer carrier and immersed in the cleaning solution.

[0061] In this embodiment, the product is vertically clamped in a special PFA material carrier. After clamping, the entire product is placed in a corrosion-resistant storage tank to ensure that the product is completely submerged in the cleaning solution and that there are no air bubbles adhering to the etched surface of the product. At the same time, it is ensured that the etched surface of each product faces the flow direction of the cleaning solution, and that the etched surface is not obstructed by any structure, but rather faces the flow direction.

[0062] 3022: The cleaning solution continuously enters from the inlet end of the storage tank and continuously exits from the outlet end of the storage tank, so as to make the cleaning solution flow in a specific direction.

[0063] In this embodiment of the present disclosure, a fluid circulation system is used in the storage tank to allow the cleaning fluid to continuously enter from the inlet end of the storage tank and continuously exit from the outlet end of the storage tank, thereby ensuring that the cleaning fluid can flow stably and continuously in a directional manner.

[0064] Optionally, by controlling the fluid circulation system, the discharge flow rate of the cleaning fluid discharged from the drain end is 20% to 30% of the inlet flow rate of the cleaning fluid entering from the inlet end.

[0065] Assuming that the amount of cleaning fluid injected into the storage tank per unit time is 100%, then the flow rate of the cleaning fluid discharged from the drain end of the storage tank is 20% to 30% of the total amount of cleaning fluid injected.

[0066] In other words, most of the cleaning solution (70%~80%) is not drained immediately, but remains in the storage tank, with only a portion being continuously replaced through overflow. This avoids damage to the products caused by drastic replacement due to liquid level fluctuations, while achieving slow and stable liquid replacement.

[0067] The product is immersed in an environment where fresh liquid is constantly flowing in while old liquid (containing acids produced by hydrolysis) continuously overflows. Compared to static immersion, the continuous injection of fresh cleaning solution dilutes and removes acidic substances generated by the hydrolysis of byproducts on the product surface, preventing localized acid accumulation and corrosion. The overflowing cleaning solution promptly removes dissolved corrosive byproducts such as gallium halides and aluminum halides from the storage tank, preventing their accumulation around the product. Compared to complete stillness, slight liquid agitation helps prevent byproduct deposition in the micro-regions of the etched structure without physically impacting the product's fine structure.

[0068] In this embodiment, the fluid circulation system includes a water supply unit, a constant temperature sealing unit, a wafer carrier, a variable frequency water flow control unit, an overflow circulation filtration unit, and an online water quality monitoring unit.

[0069] The water supply unit is used to continuously inject new deionized water into the storage tank.

[0070] The thermostatic sealing unit is used to seal the storage tank and control the temperature inside the storage tank to ensure that the temperature inside the storage tank remains constant.

[0071] Wafer carriers are used to clamp wafers, ensuring that the wafers are completely immersed in the cleaning solution in the storage tank.

[0072] The variable frequency water flow control unit is used to control the flow rate of the cleaning solution in the storage tank. The control unit includes a water pump; by changing the power supply frequency of the pump motor, the pump speed is adjusted, thereby changing the flow rate of the cleaning solution in the storage tank.

[0073] The overflow circulation filtration unit is used to continuously discharge the cleaning solution in the storage tank, and the discharged cleaning solution is filtered by the filter element to remove particulate matter, by-product sediments, bacteria, etc., keeping the cleaning solution clean, and then transferred to the water supply unit for circulation.

[0074] The online water quality monitoring unit is used to monitor the resistivity, pH value, temperature, and halide ion concentration of the cleaning solution in the storage tank.

[0075] In another example, a circulating spray system can also be used to preserve the products.

[0076] High-purity cleaning solution is evenly sprayed onto the etched surface of the product using a fan-shaped cleaning nozzle. The spraying pressure is controlled at 0.05MPa~0.2MPa, making it suitable for batch storage of large-size wafers.

[0077] S303: Real-time detection of the concentration of halide ions in the cleaning solution, and when the concentration of halide ions in the cleaning solution is higher than 10 ppb, increase the flow rate of the cleaning solution.

[0078] In the above implementation, the surface of the product after AlGaInP etching itself adsorbs trace amounts of halide ions (from metal halides that have not been completely volatilized).

[0079] After AlGaInP etching is placed in the storage tank, if the halide ion concentration in the cleaning solution is too high (e.g., >10 ppb), the halide ions in the cleaning solution will interact with the residual halide ions on the product surface, directly corroding the exposed AlGaInP heterojunction interface. This is because halide ions (especially Cl-) can cause corrosion. - It has extremely strong coordination ability, which can break the III-V bonds of III-V semiconductors, form soluble complexes, and cause pitting corrosion on the material surface.

[0080] Moreover, there is a potential difference between different semiconductor layers (such as n-type and p-type regions). Halogen ions, as active anions in the electrolyte, will accelerate the dissolution of metal in the anode region, causing local perforation at the edge of the PN junction.

[0081] When the concentration of halide ions is controlled at ≤10ppb, the cleaning solution cannot provide a sufficient concentration of active ions to directly attack semiconductor bonds, nor can it form an effective electrochemical circuit. Thus, the only source of residual halide ions on the product surface is limited to the etching process itself, and they are gradually diluted and discharged by subsequent dynamic rinsing.

[0082] In this embodiment, when the concentration of halide ions in the cleaning solution is greater than 10 ppb, the concentration of halide ions in the cleaning solution can be reduced by increasing the flow rate of the cleaning solution or by replacing the cleaning solution.

[0083] Optionally, the product is stored in the storage tank for 72 hours or less.

[0084] In the above implementation, since the surface of the product is covered with photoresist, and photoresist (especially chemical amplification photoresist or some deep ultraviolet photoresist) is hygroscopic, when the product is immersed in the cleaning solution, such as water, for a long time, the photoresist on the product will absorb water, causing the photoresist layer to soften and expand in volume. This may cause the adhesion between the photoresist and the product to decrease, resulting in edge lifting or local detachment, or deformation or collapse of fine patterns (such as submicron linewidths). Moreover, some photoresists contain small molecule plasticizers or unreacted photosensitive compounds, which may gradually precipitate into the water after long-term immersion, making the photoresist brittle and fragile. During subsequent photoresist removal, it may break into tiny particles, making it difficult to remove completely.

[0085] Furthermore, when the product is immersed in water for a long time, the final products of the hydrolysis of metal halides (such as AlCl3) are metal hydroxides or oxides (Al(OH)3, Al2O3, etc.). These substances have extremely low solubility in water, and once formed, they adhere to the etched sidewalls and photoresist surface in the form of nanoparticles or gel-like precipitates. These precipitates are more difficult to remove than the original halides (they are insoluble in water and not easily soluble in ordinary photoresist removers), which increases the difficulty of subsequent cleaning.

[0086] S304: Remove glue from preserved products.

[0087] After storage, the products can be directly removed and proceeded to the subsequent standard degumming and cleaning process without any additional pretreatment.

[0088] Through comparative testing, after storing the product for 72 hours using the preservation method provided in this embodiment, the reverse leakage current change rate of the PN junction of the device is ≤5%, the reverse breakdown voltage decay is ≤1%, and there are no interface corrosion marks.

[0089] However, when the same product is stored in a dry state for 24 hours, the leakage current of the device increases by 2 to 3 orders of magnitude, and the breakdown voltage decreases by more than 15%.

[0090] As can be seen, the preservation method provided in this embodiment can effectively preserve the product and greatly reduce corrosion.

[0091] In this embodiment, corrosion during product storage can be blocked at the source, and free halogens and hydrolyzed acid can be carried away in real time through a continuously flowing medium, thus completely avoiding corrosion of the PN junction by etching byproducts.

[0092] Moreover, it can also simultaneously improve the efficiency of subsequent glue removal.

[0093] The entire process of liquid phase wetting keeps the photoresist in a swollen state, completely avoiding cross-linking and curing. The pre-removal rate of etching byproducts exceeds 60%, and the subsequent photoresist removal time is shortened by more than 40%. The removal rate of byproducts at the bottom of high aspect ratio structures is increased to 99.99%, eliminating the need for additional strong corrosion cleaning steps.

[0094] At the same time, it can also greatly improve mass production adaptability.

[0095] The process window for removing resist after etching has been extended from a maximum of 2 hours to 72 hours, perfectly adapting to production line scheduling needs and completely solving the problem of batch scrapping caused by the inability to remove resist in time. The batch yield of AlGaInP devices has increased from 72% to over 98%.

[0096] The preservation method provided in the embodiments of this disclosure is free of strong corrosive reagents and high-temperature processes, and does not damage AlGaInP materials, PN junctions, or metal layers. It is fully compatible with existing semiconductor manufacturing processes. The equipment investment is only 1 / 5 of that of traditional vacuum storage systems, and the operating cost is only 1 / 10 of that of nitrogen cabinet storage. It can be directly connected to existing production lines and is easy to mass-produce.

[0097] This embodiment also provides a product preservation system, the preservation system including: The storage tank contains a flowing cleaning solution. The storage tank is used to store the product, and during storage, the product is immersed in the cleaning solution with the etched surface of the product facing the direction of the cleaning solution flow.

[0098] The above-mentioned storage system has the same beneficial effects as the aforementioned storage method, and will not be described in detail here.

[0099] Optionally, the storage system also includes a water supply unit, a constant temperature sealing unit, a wafer carrier, a variable frequency water flow control unit, an overflow circulation filtration unit, and an online water quality monitoring unit.

[0100] The water supply unit is used to continuously inject new deionized water into the storage tank.

[0101] The thermostatic sealing unit is used to seal the storage tank and control the temperature inside the storage tank to ensure that the temperature inside the storage tank remains constant.

[0102] Wafer carriers are used to clamp wafers, ensuring that the wafers are completely immersed in the cleaning solution in the storage tank.

[0103] The variable frequency water flow control unit is used to control the flow rate of the cleaning solution in the storage tank. The control unit includes a water pump; by changing the power supply frequency of the pump motor, the pump speed is adjusted, thereby changing the flow rate of the cleaning solution in the storage tank.

[0104] The overflow circulation filtration unit is used to allow the cleaning solution in the storage tank to continuously overflow. The overflowing cleaning solution is filtered by the filter element to remove particulate matter, by-product sediments, bacteria, etc., keeping the cleaning solution clean, and then transferred to the water supply unit for circulation.

[0105] The online water quality monitoring unit is used to monitor the resistivity, pH value, temperature, and halide ion concentration of the cleaning solution in the storage tank.

[0106] Unless otherwise defined, the technical or scientific terms used herein shall have the ordinary meaning understood by one of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” “third,” and similar terms used in this patent application specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the terms “an” or “a” and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. The terms “comprising” or “including” and similar terms mean that the elements or objects preceding “comprising” or “including” encompass the elements or objects listed following “comprising” or “including” and their equivalents, and do not exclude other elements or objects. The terms “connected” or “linked” and similar terms are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. The terms “upper,” “lower,” “left,” “right,” etc., are used only to indicate relative positional relationships; when the absolute position of the described objects changes, the relative positional relationship may also change accordingly.

[0107] The above description is merely an optional embodiment of this disclosure and is not intended to limit this disclosure. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this disclosure should be included within the protection scope of this disclosure.

Claims

1. A method for preserving a product, characterized in that, For preserving products after low-temperature halogen etching, the preservation method includes: The product is placed in a storage tank containing a flowing cleaning solution, the product is immersed in the cleaning solution, and the etched surface of the product faces the flow direction of the cleaning solution.

2. The preservation method according to claim 1, characterized in that, The temperature of the cleaning solution is 18℃~25℃.

3. The preservation method according to claim 1, characterized in that, The flow rate of the cleaning fluid is 0.2 m / s to 1.5 m / s.

4. The preservation method according to claim 1, characterized in that, The resistivity of the cleaning fluid is greater than or equal to 18.2 MΩ. cm.

5. The preservation method according to claim 1, characterized in that, The pH of the cleaning solution is 6.5~7.

5.

6. The preservation method according to claim 1, characterized in that, The step of placing the product in a storage tank for preservation includes: The product is fixed in the storage tank using a wafer carrier; The cleaning fluid is continuously introduced into the storage tank from the inlet and continuously discharged from the outlet of the storage tank, so that the cleaning fluid flows in a directional manner.

7. The preservation method according to claim 6, characterized in that, The discharge flow rate of the cleaning fluid from the drain end is 20% to 30% of the inflow flow rate of the cleaning fluid from the inlet end.

8. The preservation method according to claim 6, characterized in that, After placing the product in the storage tank, the storage method further includes: The concentration of halide ions in the cleaning solution is detected, and when the concentration of halide ions in the cleaning solution is higher than 10 ppb, the flow rate of the cleaning solution is increased.

9. The preservation method according to any one of claims 1-8, characterized in that, The cleaning solution is deionized water, anhydrous ethanol, or anhydrous isopropanol.

10. A preservation system for an article, characterized in that, The storage system includes: A storage tank containing a flowing cleaning solution is used to store a product, wherein the product is immersed in the cleaning solution during storage, and the etched surface of the product faces the flow direction of the cleaning solution.

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