Method for improving back surface handwriting absorption of silicon wafer
By pretreating the silicon wafer and curing the anti-handwriting penetration membrane, combined with the use of a vacuum pressure valve, the marking problem left by the back of the silicon wafer due to the contact of the pen is solved, and the protection effect of the product and customer satisfaction are improved. Spend.
Patent Information
- Application Number
- CN202411352304.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-26
- Publication Date
- 2024-12-31
AI Technical Summary
The prior art cannot effectively avoid the marking problem left by the back of the silicon wafer due to the contact of the pen, which affects the product's aesthetics and customer satisfaction.
By pretreating the silicon wafer to improve the cleanliness and roughness of the back, attaching a screened anti-handwriting membrane, and controlling the combination of the membrane with the silicon wafer in the curing process, secondary treatment is performed to ensure that The firm adhesion of the membrane and the cleanliness of the silicon wafer.
Effectively prevent handwriting penetration, improve the protection effect on the back of the silicon wafer, reduce customer complaints, improve the safety and quality of the product during handling and processing, and improve customer satisfaction.
Smart Images
Figure CN119230467A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of semiconductor manufacturing technology, and in particular to a method for improving the absorption of pen marks on the back side of a silicon wafer. Background Art
[0002] As the basic material of the semiconductor industry, silicon wafers play a vital role in modern electronic technology. They are widely used in many fields such as semiconductor manufacturing, integrated circuits, solar cells, LEDs, etc. With the continuous development of electronic technology, the quality requirements for silicon wafers are getting higher and higher. In the existing production, processing and transportation of silicon wafers, Poly film is often used as a protective layer and attached to the back of the product. However, when using a suction pen or other tools to touch the surface of the product, marks are often left on the back of the Poly film. These marks not only affect the appearance of the product, but also become more obvious after a specific process, such as the epitaxial process, which causes customer dissatisfaction and complaints.
[0003] However, the inventors have discovered that the related art has at least the following technical problems: the related art cannot effectively avoid the mark problem caused by the suction pen contacting the silicon wafer. Summary of the invention
[0004] One purpose of the present application is to provide a method for improving the mark of the suction pen on the back of a silicon wafer, at least to solve the mark problem caused by the suction pen contacting the silicon wafer.
[0005] To achieve the above objectives, some embodiments of the present application provide the following aspects:
[0006] In a first aspect, some embodiments of the present application further provide a method for improving the absorption of pen marks on the back side of a silicon wafer, comprising:
[0007] Pre-processing the silicon wafer;
[0008] Attaching an anti-pencil penetration film to the back of the pre-treated silicon wafer;
[0009] Performing a curing treatment on the silicon wafer to which the anti-handwriting penetration film has been attached;
[0010] A secondary treatment is performed based on the silicon wafer after the curing treatment.
[0011] Compared with the related art, in the solution provided by the embodiment of the present application, the silicon wafer is pre-treated, deeply cleaned and the back of the silicon wafer can be roughened according to the actual situation to improve the binding force of the subsequent anti-handwriting penetration membrane; the anti-handwriting penetration membrane that has been strictly screened is attached to the back of the pre-treated silicon wafer to effectively prevent handwriting from penetrating to the back of the silicon wafer; the silicon wafer with the film attached is cured, and a vacuum pressure valve is installed to control it within a specific pressure range to ensure that the membrane is firmly and stably bonded to the silicon wafer; then secondary treatment is performed, surface inspection, re-cleaning to remove impurities and make the silicon wafer flow, to ensure that the silicon wafer has good performance, stability and reliability during subsequent use, and overall achieves effective improvement in the absorption of handwriting on the back of the silicon wafer. This application improves the safety and quality of products during transportation and handling through technical improvements and optimization of operating procedures, reduces customer complaints, and improves satisfaction. BRIEF DESCRIPTION OF THE DRAWINGS
[0012] One or more embodiments are exemplarily described by pictures in the corresponding drawings, and these exemplified descriptions do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and unless otherwise stated, the figures in the drawings do not constitute proportional limitations.
[0013] Figure 1 This is a schematic diagram of an exemplary process of a method for improving the absorption of pen marks on the back side of a silicon wafer according to the first embodiment of the present application;
[0014] Figure 2 It is a schematic diagram of the structure of the polyethylene film provided according to the second embodiment of the present application. DETAILED DESCRIPTION
[0015] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.
[0016] The following terms are used in this article.
[0017] Epitaxy: the process of growing a single crystal thin film with specific crystal structure and electrical properties on a single crystal substrate (such as a silicon wafer);
[0018] Poly film: In the field of semiconductor manufacturing, it refers to polycrystalline silicon film.
[0019] First embodiment
[0020] The first embodiment of the present application relates to a method for improving the absorption of pen marks on the back side of a silicon wafer. Figure 1 As shown, the method may include the following steps:
[0021] Step S101: pre-treating the silicon wafer;
[0022] Step S102: attaching an anti-handwriting penetration film to the back of the pre-treated silicon wafer;
[0023] Step S103: curing the silicon wafer to which the anti-handwriting penetration film has been attached;
[0024] Step S104: performing secondary processing based on the silicon wafer after the curing process.
[0025] The following is a detailed description of each of the above steps.
[0026] For step S101, specifically, in some embodiments, the silicon wafer is first subjected to a comprehensive and detailed pretreatment operation. During the pretreatment process, professional cleaning tools and cleaning agents are required to deeply clean the back of the silicon wafer to remove dust, oil and other impurities on the back, and ensure that the cleanliness of the back of the silicon wafer meets specific standards. Exemplarily, the professional cleaning tools may include: ultrapure water cleaning system, megasonic cleaning equipment, rotary spray cleaning equipment, dust-free wiping cloth, microfiltration membrane filter, etc.; the cleaning agents may include: organic solvents, hydrogen peroxide, acidic or alkaline solutions, which can be selected according to actual needs. In addition, the back of the silicon wafer can also be roughened according to actual conditions, and the roughness of the back of the silicon wafer can be increased by specific mechanical or chemical methods, thereby improving the bonding strength between the anti-handwriting penetration membrane and the back of the silicon wafer in subsequent steps.
[0027] Regarding step S102, specifically, in some embodiments, the anti-handwriting penetration film is precisely attached to the back of the silicon wafer after the pretreatment. The anti-handwriting penetration film should have good anti-handwriting penetration performance, flexibility and wear resistance, and can effectively prevent handwriting from penetrating to the back of the silicon wafer.
[0028] Regarding step S103, specifically, in some embodiments, the curing process can further promote the formation of a stronger chemical bond or physical adsorption between the anti-handwriting permeation film and the silicon wafer, so that the anti-handwriting permeation film can be more firmly adsorbed on the back of the silicon wafer. For example, during the semiconductor processing process, the silicon wafer will experience various mechanical stresses and chemical environments. If the bonding force of the attached anti-handwriting permeation film is insufficient, the anti-handwriting permeation film is likely to fall off or shift, thereby affecting the protective effect.
[0029] For step S104, the silicon wafer after the curing treatment is subjected to secondary treatment. During the secondary treatment, the silicon wafer needs to be inspected to check the adhesion of the anti-pencil penetration film and whether there are any defects. If any problems are found, they should be dealt with in a timely manner. After the surface inspection is completed, the silicon wafer is re-cleaned to remove impurities that may be generated during the secondary treatment. After cleaning, the silicon wafer is allowed to flow to ensure that it can maintain good performance during subsequent use.
[0030] It is not difficult to find that compared with the related art, the solution provided in the embodiment of the present application pre-treats the silicon wafer, deeply cleans it, and can roughen the back of the silicon wafer according to actual conditions, thereby improving the binding force of the subsequent anti-handwriting penetration membrane; a strictly screened anti-handwriting penetration membrane is attached to the back of the pre-treated silicon wafer to effectively prevent handwriting from penetrating to the back of the silicon wafer; the silicon wafer with the attached film is cured, and a vacuum pressure valve is installed to control it within a specific pressure range to ensure that the film is firmly and stably bonded to the silicon wafer; and then a secondary treatment is performed, including surface inspection, re-cleaning to remove impurities, and making the silicon wafer flow, to ensure that the silicon wafer has good performance, stability and reliability during subsequent use, and overall achieves effective improvement in the absorption of handwriting on the back of the silicon wafer. This application improves the safety and quality of products during transportation and handling, reduces customer complaints, and improves satisfaction through technical improvements and optimization of operating procedures.
[0031] Second embodiment
[0032] The second embodiment of the present application relates to a method for improving backside absorption of handwriting. The second implementation is an improvement on the first embodiment, and the specific improvement is: providing a specific implementation method of the anti-handwriting penetration film.
[0033] The anti-handwriting penetration film is a polyethylene film.
[0034] Specifically, in some embodiments, combined with Figure 2 Since polyethylene is composed of repeating ethylene monomers, its molecular structure is tight and has a certain degree of crystallinity, and its permeability to liquids and small molecules is low. This structure enables the polyethylene film to have a good blocking effect on ink, pigments and other substances in handwriting, and can effectively prevent handwriting from penetrating to the back of the silicon wafer.
[0035] The thickness of the polyethylene film is between 10 μm and 20 μm.
[0036] Preferably, the polyethylene film may have a thickness of 15 μm.
[0037] Specifically, a thickness of 15 μm can ensure the strength of the film to a certain extent, reduce the risk of damage during operation, and provide more reliable protection; at the same time, it is not too thick to have a significant impact on the overall performance of the silicon wafer or significantly increase the difficulty of the process, and can better meet the requirements of semiconductor processing technology. For example, if a thinner one is selected, it is easy to break during operation and it is difficult to provide sufficient protection; a thicker one may affect the overall performance of the silicon wafer or increase the difficulty of the process.
[0038] Specifically, in some embodiments, the polyethylene film should be selected considering its thickness, transparency, tensile strength, thermal stability, chemical stability, etc. Exemplarily, various stresses and operations in the semiconductor processing process can ensure that the polyethylene film is not easy to break during transportation, processing, etc., and can be stably attached to the back of the silicon wafer to provide effective protection.
[0039] It is not difficult to find that in the embodiment of the present application, the present application uses a polyethylene film with a thickness of 10 μm to 20 μm as an anti-handwriting penetration film. On the one hand, it can effectively prevent handwriting penetration; on the other hand, it does not increase too much thickness and weight, is not easy to fall off and damage, and improves durability and stability. In addition, the polyethylene film is low in cost and easy to produce and process, which is conducive to large-scale application in writing products, providing consumers with a cost-effective solution.
[0040] Third embodiment
[0041] The third embodiment of the present application relates to a method for improving backside ink absorption. The third embodiment is an improvement made on the basis of the first embodiment, and the specific improvement is: providing a specific implementation of the curing process.
[0042] The curing process includes: installing a vacuum pressure valve on the silicon wafer to which the anti-handwriting penetration film has been attached;
[0043] Wherein, the pressure range of the vacuum pressure valve is: 60-70pa.
[0044] The vacuum pressure valve can automatically adjust its own pressure in real time.
[0045] The vacuum pressure valve adjusts the pressure in the system through a closed-loop PID control loop;
[0046] When the pressure in the system deviates from the set pressure value, the vacuum pressure valve detects the pressure change, and the PID control loop calculates a control signal based on the pressure change detected by the vacuum pressure valve, and adjusts the opening and closing of the vacuum pressure valve to increase or decrease the pressure in the system.
[0047] Specifically, in some embodiments, the vacuum pressure valve is installed on the silicon wafer to which the anti-handwriting permeation film has been attached, ensuring that the installation is firm and the seal is good, and the pressure range of the vacuum pressure valve is adjusted to 60-70pa. The vacuum pressure valve adjusts the pressure in the system through a closed-loop PID control loop. Exemplarily, when the pressure value in the system is lower than the set pressure value, the PID control loop controls the valve of the vacuum pressure valve to open, allowing external gas to enter the system to prevent the pressure in the system from being too low. The too low pressure will affect the ability of the anti-handwriting permeation film to be attached, and even cause the silicon wafer and the anti-handwriting permeation film to be delaminated, which will not protect the silicon wafer. When the pressure value in the system is higher than the set pressure value, the PID control loop controls the valve of the vacuum pressure valve to open, and the excess gas or fluid is discharged from the system to prevent the pressure in the system from being too high, thereby causing the silicon wafer to deform or warp, further affecting the performance, and maintaining the system pressure within a safe range. After a certain period of curing treatment, when the anti-handwriting permeation film is fully combined with the silicon wafer, the curing process is completed. At this time, the PID control loop controls the vacuum pressure valve to close the valve.
[0048] It should be noted that the system is a closed or semi-closed space area consisting of a silicon wafer with an anti-handwriting penetration film attached thereto and a vacuum pressure valve installed thereon.
[0049] It is not difficult to find that in the embodiment of the present application, by installing a vacuum pressure valve on the silicon wafer with an anti-handwriting penetration film, the pressure is controlled within the range of 60-70pa, and the vacuum pressure valve can automatically adjust the pressure in real time, thereby ensuring the stability of the curing environment, improving the bonding quality between the anti-handwriting penetration film and the silicon wafer, improving production efficiency and reducing manual intervention.
[0050] Fourth embodiment
[0051] The fourth embodiment of the present application relates to a method for improving back-side ink absorption. The fourth embodiment is an improvement made on the basis of the first embodiment, and the specific improvement is: providing a specific implementation of the secondary processing.
[0052] The secondary treatment includes: performing surface inspection on the silicon wafer and re-cleaning and then flowing.
[0053] The silicon wafer does not contact the suction pen during the secondary treatment.
[0054] Specifically, in some embodiments, the surface inspection may include: whether there are bubbles, dust, oil and other impurities; whether the back side of the silicon wafer is flat; whether the polyethylene film is completely and evenly attached to the silicon wafer, etc.
[0055] The silicon wafer after the inspection is then subjected to final cleaning to remove slight contamination found during the inspection process, thereby ensuring that the silicon wafer meets higher cleanliness requirements. The final cleaning process may include: selecting a cleaning solution (deionized water, organic solution, certain specific cleaning agents, etc.), a cleaning method (immersion cleaning, spray cleaning, ultrasonic cleaning, etc.), and parameter control (time, temperature, strength, etc.).
[0056] After the final cleaning is completed, the silicon wafer enters the flow link, wherein the flow link is a conveying device for the silicon wafer through an assembly line to ensure that the silicon wafer can be smoothly and orderly transferred from one processing link to the next processing link.
[0057] It should be noted that during the entire secondary processing, the silicon wafer does not touch the suction pen. When the suction pen touches the silicon wafer, it may cause physical damage to the silicon wafer, such as scratches and indentations, due to improper manual operation or problems with the suction pen itself, affecting the appearance quality of the silicon wafer, and further affecting the quality and efficiency of the entire production process, and reducing customer satisfaction.
[0058] The step division of the above methods is only for the purpose of clear description. When implemented, they can be combined into one step or some steps can be split and decomposed into multiple steps. As long as they include the same logical relationship, they are all within the scope of protection of this patent; adding insignificant modifications to the algorithm or process or introducing insignificant designs without changing the core design of the algorithm and process are all within the scope of protection of this patent.
[0059] The flow chart or block diagram in the accompanying drawings shows the possible architecture, function and operation of the equipment, method and computer program product according to various embodiments of the present application. In this regard, each box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flow chart, and the combination of the boxes in the block diagram and / or flow chart can be implemented with a dedicated system for hardware that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.
[0060] The scope of the present application is defined by the appended claims rather than the above description, and it is intended that all changes that fall within the meaning and scope of the equivalent elements of the claims are included in the present application. Any figure mark in the claims should not be regarded as limiting the claims involved. In addition, it is clear that the word "comprising" does not exclude other units or steps, and the singular does not exclude the plural. Multiple units or devices stated in the device claim may also be implemented by one unit or device through software or hardware. The words "first", "second", etc. are only used to distinguish the description, and do not indicate any particular order, nor can they be understood as indicating or implying relative importance.
[0061] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily mention changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims, and the above embodiments should be regarded as exemplary and non-restrictive.
Claims
1. A method for improving the absorption of pen marks on the back side of a silicon wafer, characterized in that: The method comprises: Pre-processing the silicon wafer; Attaching an anti-pencil penetration film to the back of the pre-treated silicon wafer; Performing a curing treatment on the silicon wafer to which the anti-handwriting penetration film has been attached; A secondary treatment is performed based on the silicon wafer after the curing treatment.
2. The method according to claim 1, characterized in that The anti-handwriting penetration film is a polyethylene film.
3. The method according to claim 2, characterized in that The thickness of the polyethylene film is between 10 μm and 20 μm.
4. The method according to claim 1, characterized in that: The curing process includes: installing a vacuum pressure valve on the silicon wafer to which the anti-handwriting penetration film has been attached.
5. The method according to claim 4, characterized in that The pressure range of the vacuum pressure valve is: 60-70pa.
6. The method according to claim 4 or 5, characterized in that: The vacuum pressure valve can automatically adjust its own pressure in real time.
7. The method according to claim 6, characterized in that The vacuum pressure valve adjusts the pressure in the system through a closed-loop PID control loop; When the pressure in the system deviates from the set pressure value, the vacuum pressure valve detects the pressure change, and the PID control loop calculates a control signal based on the pressure change detected by the vacuum pressure valve, and adjusts the opening and closing of the vacuum pressure valve to increase or decrease the pressure in the system.
8. The method according to claim 1, characterized in that The secondary treatment includes: performing surface inspection on the silicon wafer and re-cleaning and then flowing.
9. The method according to claim 8, characterized in that The silicon wafer does not contact the suction pen during the secondary treatment.