High copper cylinder processing method and system for wafer substrate, terminal and storage medium
By employing a step-by-step electroplating and etching process, the problem of copper pillar tilting was solved, enabling precise control over the height and shape of the high-strength copper pillars and improving the bonding strength and electroplating uniformity of the copper pillars.
Patent Information
- Application Number
- CN202511744753.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-25
- Publication Date
- 2026-03-06
AI Technical Summary
In chip manufacturing, as chip size shrinks and the height of copper pillars increases, the copper pillars are prone to tilting or falling over, and existing technologies struggle to effectively control the height and shape accuracy of the copper pillars.
A step-by-step electroplating process is adopted, in which a photoresist layer is coated on the wafer to form an opening, and copper pillars are electroplated layer by layer. Combined with molding and etching processes, the uniformity and bonding strength of the copper pillars are ensured.
This improved the height and shape accuracy of the copper pillars, reduced their tilt angle, enhanced their bonding strength and electroplating uniformity, and ensured the overall processing quality of the high-strength copper pillars.
Smart Images
Figure CN121620186A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of chip fabrication, and in particular to a method, system, terminal, and storage medium for fabricating high copper pillars on a wafer substrate. Background Technology
[0002] In chip manufacturing, copper pillars in chips are mainly used for electrical interconnection and physical connection between chips or between chips and packaging substrates. It is one of the key technologies for achieving high-performance, high-density, and small-size packaging.
[0003] The relevant technology defines a fine pattern window on the wafer at the location where copper pillars need to be formed through photolithography steps such as spin coating, exposure, and development. Subsequently, metallic copper is deposited within the pattern window through an electroplating process. As the copper continues to accumulate, it gradually fills the window and eventually forms a columnar structure, thus obtaining the copper pillar.
[0004] Regarding the aforementioned technologies, as chip size shrinks, copper pillar size also shrinks. However, when the copper pillar is tall, it may tilt or even fall over. Summary of the Invention
[0005] To reduce the tilt angle of the copper pillars, this application provides a method, system, terminal, and storage medium for processing high copper pillars on a wafer substrate.
[0006] In a first aspect, this application provides a method for processing high-copper pillars on a wafer substrate, employing the following technical solution: A method for fabricating high-copper pillars on a wafer substrate, comprising: A first photoresist layer is coated onto the wafer; A first opening is formed at the location of the copper pillar in the first photoresist layer; A first layer of copper pillars is formed inside the first opening through an electroplating process; Remove the first photoresist layer; A molding compound is formed on the wafer to cover the first copper pillar. The molding layer is ground to expose the first copper pillar layer; A second photoresist layer is coated on the molding layer; A second opening is formed at the location of the copper pillar in the second photoresist layer, and the second opening exposes the first copper pillar. A second layer of copper pillars is formed inside the second opening through an electroplating process, so that the first layer of copper pillars and the second layer of copper pillars are combined into a high copper pillar. Remove the second photoresist layer; Grinding removes the wafer; A protective layer is formed on the surface of the high copper pillar.
[0007] By adopting the above technical solution, a high copper pillar is formed through a step-by-step electroplating process: first, a first photoresist layer is coated on the wafer to form a first opening; after electroplating the first copper pillar, the photoresist is removed; a molding compound is formed to cover the first copper pillar and then ground to expose it; next, a second photoresist layer is coated to form a second opening; the second copper pillar is then electroplated and bonded to the first copper pillar; finally, the photoresist is removed, the wafer is ground, and a protective layer is formed. This avoids the uniformity problem of high copper pillars in a single electroplating process, improves the height and shape accuracy of the copper pillars, and reduces the tilt angle of the copper pillars.
[0008] Optionally, a third opening is formed at the copper pillar position of the second photoresist layer, the size of the third opening being smaller than the size of the second opening, and the third opening exposing the first copper pillar; The top of the first layer of copper pillars is etched along the third opening; Based on the third opening, the second photoresist layer is removed to form the second opening.
[0009] By employing the above technical solution, a smaller third opening is first formed on the second photoresist layer to expose the first copper pillar and etch its top. Then, a second opening is formed based on the third opening through a removal operation. This step-by-step method of forming the second opening allows for more precise control over the size and shape of the opening, ensuring that the top of the first copper pillar is uniformly etched. This provides a flat and clean bonding surface for the subsequent electroplating of the second copper pillar, avoiding alignment errors or uneven etching that may result from directly forming a large opening. This improves the bonding strength and electroplating uniformity of the high-strength copper pillar.
[0010] Optionally, a first region and a second region are determined on the first layer of copper pillars. The first region is the projection area of the third opening on the first layer of copper pillars, and the second region is the region other than the first region within the projection area of the second opening on the first layer of copper pillars. Obtain the first height value corresponding to the first region; Obtain the second height value corresponding to the second region; Calculate the difference between the first height value and the second height value to obtain the height difference; If the height difference is greater than a preset height difference threshold, then the second region is etched according to the height difference.
[0011] By employing the above technical solution, a first region and a second region on the first layer of copper pillars are identified, a first height value of the first region and a second height value of the second region are obtained, the height difference is calculated, and the second region is etched when the height difference exceeds a preset threshold. This method can detect and compensate for the height non-uniformity at the top of the first layer of copper pillars. Through selective etching, the height of the second region is made consistent with that of the first region, ensuring the flatness of the top of the first layer of copper pillars. This provides a uniform foundation for the subsequent electroplating of the second layer of copper pillars, reduces the height deviation of tall copper pillars, and improves the reliability and performance of the product.
[0012] Optionally, the inner radius and outer radius of the second region can be obtained; Using the inner radius and the outer radius as the domain, and the height difference as a constant term, a first processing function is generated. The first processing function is used to describe the relationship between the etching position and the etching depth in the second region. The first processing function is an increasing function. The second region is etched according to the first processing function.
[0013] By employing the above technical solution, the inner and outer radii of the second region are obtained, and a first processing function is generated with the height difference as a constant. This function describes the relationship between the etching position and the etching depth and is an increasing function. The second region is then etched according to this function. This function-based etching method enables precise control of the etching depth, adaptively adjusting etching parameters based on the region's geometric characteristics to ensure that the second region is uniformly etched to the same height as the first region. This avoids over-etching or under-etching, improving the flatness and bonding quality of the high-copper pillar substrate.
[0014] Optionally, obtain the first height value corresponding to the first region; The deposition thickness distribution is set according to the first height value; A copper layer is formed on top of the first copper pillar within the third opening using a deposition process, according to the deposition thickness distribution.
[0015] By adopting the above technical solution, a first height value corresponding to the first region is obtained before the second opening is formed. Based on this value, the deposition thickness distribution is set, and a copper layer is formed on the top of the first copper pillar within the third opening through a deposition process. This method allows for selective deposition of a copper layer on the top of the first copper pillar according to the actual height value, compensating for insufficient height and ensuring the top of the first copper pillar reaches the ideal height. This provides a uniform base surface for subsequent electroplating of the second copper pillar, reduces the impact of height deviation on the formation of tall copper pillars, and improves the bonding consistency and overall height accuracy of the copper pillars.
[0016] Optionally, a second processing function is obtained, which describes the relationship between the deposition location and the ideal height in the first region; Generate the ideal height distribution according to the second processing function; The deposition thickness distribution is generated according to the ideal deposition thickness distribution and the first height value.
[0017] By adopting the above technical solution, the first region is circular. A second processing function is obtained to describe the relationship between the deposition position and the ideal height. Based on this function, an ideal height distribution is generated, and combined with the first height value, a deposition thickness distribution is generated. This function-based deposition control method can achieve precise adjustment of the deposition thickness, optimize deposition parameters according to the region shape and height requirements, ensure that the copper layer deposited at the top of the first copper pillar is uniform in thickness and meets the ideal height, avoid uneven deposition or height errors, and improve the flatness of the high copper pillar substrate and the electroplating effect.
[0018] Optionally, obtain the current etching parameters; Obtain standard etching parameters; If the difference between the current etching parameter and the standard etching parameter is greater than the preset parameter difference, the current etching parameter is adjusted according to the standard etching parameter.
[0019] By adopting the above technical solution, the current etching parameters and standard etching parameters are obtained. When the difference between the current etching parameters and the standard etching parameters exceeds the preset parameter difference, the current etching parameters are adjusted according to the standard etching parameters. This method can detect and correct deviations in etching parameters in real time, ensuring the stability and repeatability of the etching process. It avoids uneven etching or over-etching caused by parameter drift, improves the accuracy of the top processing of the first layer of copper pillars, and thus improves the overall processing quality and product yield of high copper pillars.
[0020] Secondly, this application provides a high-copper pillar processing system for wafer substrates, employing the following technical solution: A high-copper pillar processing system for wafer substrates includes: The acquisition module is used to acquire data related to the high copper pillar processing method of the wafer substrate; A memory for storing a program for processing the high copper pillars of the wafer substrate; The processor and the program in the memory can be loaded and executed by the processor to implement the high copper pillar processing method of the wafer substrate.
[0021] By adopting the above technical solution, a high copper pillar is formed through a step-by-step electroplating process: first, a first photoresist layer is coated on the wafer to form a first opening; after electroplating the first copper pillar, the photoresist is removed; a molding compound is formed to cover the first copper pillar and then ground to expose it; next, a second photoresist layer is coated to form a second opening; the second copper pillar is then electroplated and bonded to the first copper pillar; finally, the photoresist is removed, the wafer is ground, and a protective layer is formed. This avoids the uniformity problem of high copper pillars in a single electroplating process, improves the height and shape accuracy of the copper pillars, and reduces the tilt angle of the copper pillars.
[0022] Thirdly, this application provides a smart terminal, which adopts the following technical solution: A smart terminal includes a memory and a processor, wherein the memory stores a computer program that can be loaded by the processor and execute the method described in any of the above-mentioned embodiments.
[0023] Fourthly, this application provides a computer storage medium capable of storing corresponding programs, which facilitates reducing the tilt angle of the copper pillar, and adopts the following technical solution: A computer-readable storage medium storing a computer program that can be loaded by a processor and executed as a high-copper pillar fabrication method for any of the above-described wafer substrates.
[0024] In summary, this application includes at least one of the following beneficial technical effects: 1. Forming high copper pillars through a step-by-step electroplating process: First, a first photoresist layer is coated on the wafer to form a first opening. After electroplating the first copper pillar, the photoresist is removed. A molding compound is formed to cover the first copper pillar and then ground to expose it. Next, a second photoresist layer is coated to form a second opening. The second copper pillar is then electroplated to bond with the first copper pillar. Finally, the photoresist is removed, the wafer is ground, and a protective layer is formed. This avoids the uniformity problem of single-stage high copper pillar plating, improves the height and shape accuracy of the copper pillars, and reduces the tilt angle of the copper pillars. 2. By first forming a smaller third opening on the second photoresist layer to expose the first copper pillar and etching its top, and then forming the second opening based on the third opening through a removal operation, this step-by-step method of forming the second opening allows for more precise control of the opening size and shape, ensuring that the top of the first copper pillar is uniformly etched. This provides a flat and clean bonding surface for the subsequent electroplating of the second copper pillar, avoiding alignment errors or uneven etching that may result from directly forming a large opening, and improving the bonding strength and electroplating uniformity of the high copper pillars. Attached Figure Description
[0025] Figure 1 This is a schematic flowchart of a high-copper pillar processing method for a wafer substrate provided in an embodiment of this application.
[0026] Figure 2 This is a schematic diagram of a high-copper pillar processing method for a wafer substrate provided in an embodiment of this application.
[0027] Figure 3 This is a schematic flowchart of a processing method for a second opening provided in an embodiment of this application.
[0028] Figure 4 This is a schematic diagram of a first-layer copper pillar provided in an embodiment of this application. Figure 1 .
[0029] Figure 5 This is a flowchart illustrating a processing method for a second region provided in an embodiment of this application.
[0030] Figure 6 This is a flowchart illustrating a processing method for a first region provided in an embodiment of this application.
[0031] Figure 7 This is a schematic diagram of a high-copper pillar processing system for a wafer substrate provided in an embodiment of this application. Detailed Implementation
[0032] To make the purpose, technical solution, and advantages of this application clearer, the following description is provided in conjunction with the appendix. Figure 1 To be continued Figure 7 The present application will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the application.
[0033] This application discloses a method for fabricating high-copper pillars on a wafer substrate. (Refer to...) Figure 1 The method includes: Step S101: Coat the first photoresist layer on the wafer.
[0034] For example, please refer to Figure 2 A first photoresist layer 22 is coated on wafer 21.
[0035] Step S102: Form a first opening at the copper pillar position of the first photoresist layer.
[0036] The size and shape of the first opening match the copper pillar.
[0037] Optionally, a photomask is used to expose the photoresist at the copper pillar locations of the first photoresist layer. The exposed portions are then removed using a developer to form the first opening.
[0038] For example, please refer to Figure 2 The photoresist at the copper pillar position of the first photoresist layer 22 is exposed. The exposed photoresist is then removed to obtain the first opening 221.
[0039] Step S103: A first layer of copper pillar 23 is formed in the first opening 221 by electroplating.
[0040] Please refer to Figure 2 The first layer of copper pillars is formed inside the first opening through an electroplating process.
[0041] Step S104: Remove the first photoresist layer.
[0042] Optionally, the first photoresist layer can be removed using a photoresist remover.
[0043] For example, please refer to Figure 2 Remove the first photoresist layer 22.
[0044] Step S105: Form a molding compound on the wafer so that the molding compound covers the first copper pillar.
[0045] The thickness of the plastic sealant layer is greater than the height of the first copper pillar.
[0046] For example, please refer to Figure 2 A molding compound 24 is formed on wafer 21, which covers the first copper pillar 23.
[0047] Step S106: Grind the molding layer to expose the first copper pillar.
[0048] For example, please refer to Figure 2 The molding layer 24 is ground to expose the first copper pillar 23.
[0049] Step S107: Coat the second photoresist layer on the molding layer.
[0050] The material of the second photoresist layer can be the same as or different from that of the first photoresist layer.
[0051] For example, please refer to Figure 2 A second photoresist layer 25 is coated on the molding layer 24.
[0052] Step S108: A second opening is formed at the position of the copper pillar in the second photoresist layer, and the second opening exposes the first copper pillar.
[0053] The shape and size of the second opening match those of the first layer of copper pillars, so that after the second layer of copper pillars is formed, the first and second layers of copper pillars can form a complete tall copper pillar.
[0054] For example, please refer to Figure 2 A second opening 251 is formed at the position of the copper pillar in the second photoresist layer 25, and the second opening 251 exposes the first copper pillar 23.
[0055] Step S109: A second layer of copper pillar is formed in the second opening through an electroplating process, so that the first layer of copper pillar and the second layer of copper pillar are combined into a high copper pillar.
[0056] The height of the first and second layers of copper pillars can be the same or different. The height of each layer of copper pillars must be less than or equal to 100 μm, and the minimum width of each layer must be limited to 50-60 μm.
[0057] For example, please refer to Figure 2 A second layer of copper pillars is formed within the second opening 251, so that the first layer of copper pillars 23 and the second layer of copper pillars are combined to form a high copper pillar 26.
[0058] Step S110: Remove the second photoresist layer.
[0059] It should be noted that this embodiment only illustrates the case where the high copper column consists of two layers of copper columns, namely the first layer and the second layer. In actual operation, the high copper column can also be formed by stacking more copper columns.
[0060] Please refer to Figure 2 Remove the second photoresist layer 25 on the molding layer 24.
[0061] Step S111: Grinding to remove the wafer.
[0062] Optionally, a BG (bonding glass) film is formed on the wafer surface to protect the copper pillars. The wafer is then removed by grinding. The BG film is then removed.
[0063] For example, please refer to Figure 2 Grinding removes wafer 21.
[0064] Step S112: Form a protective layer on the surface of the high copper pillar.
[0065] The protective layer serves to protect the copper pillars by preventing them from oxidizing. For example, tin can be used as a material for the protective layer.
[0066] For example, please refer to Figure 2 A protective layer 27 is formed on the surface of the high copper pillar 26.
[0067] Furthermore, the chip product obtained in this step is cut into a preset size using a cutting process to obtain a single chip. Each single chip will have at least four high copper pillars distributed on it to play a balancing and stabilizing role in the subsequent mounting process and reduce the tilt angle.
[0068] Optionally, retrieve the current etching parameters. Alternatively, retrieve the standard etching parameters. If the difference between the current etching parameters and the standard etching parameters is greater than the preset parameter difference, adjust the current etching parameters according to the standard etching parameters.
[0069] The etching parameters include exposure parameters and development parameters. Exposure parameters include at least one of exposure energy, exposure wavelength, focal length, and depth of focus. Development parameters include at least one of development time, developer concentration, development temperature, and development method.
[0070] By employing the above technical solution, a high copper pillar is formed through a step-by-step electroplating process: First, a first photoresist layer is coated on the wafer to form a first opening. After electroplating the first copper pillar, the photoresist is removed. A molding compound is formed to cover the first copper pillar and then ground to expose it. Next, a second photoresist layer is coated to form a second opening, and the second copper pillar is electroplated to bond with the first copper pillar. Finally, the photoresist is removed, the wafer is ground, and a protective layer is formed. This avoids the uniformity problem of high copper pillars in a single electroplating process, improves the height and shape accuracy of the copper pillars, and reduces the tilt angle of the copper pillars.
[0071] In the following embodiments, after forming the second opening, a flat and clean bonding surface is required for the second layer of copper pillars. Therefore, embodiments of this application disclose a method for processing the second opening. (Refer to...) Figure 3 The method includes: step S301: forming a third opening at the copper pillar position of the second photoresist layer, the size of the third opening being smaller than the size of the second opening, and the third opening exposing the first copper pillar.
[0072] Because the size of the third opening is smaller than the size of the second opening, the third opening only exposes a portion of the first copper pillar, with the remaining area covered by the second photoresist layer. For example, if the size of the second opening is R, the size of the third opening can be set to 0.95R.
[0073] For example, please refer to Figure 4 A third opening is formed at the copper pillar position of the second photoresist layer.
[0074] Step S302: Etch the top of the first layer of copper pillars along the third opening.
[0075] It should be noted that after the first copper pillar is formed, its top surface is affected by the molding compound and the second photoresist layer. This results in poor uniformity on the top surface of the first copper pillar, affecting the subsequent electroplating formation of the second copper pillar. Therefore, in this step, the top of the first copper pillar is etched to remove some of the copper, making the top surface of the first copper pillar as clean and flat as possible to ensure the electroplating effect of the second copper pillar and thus avoid the tilting of the tall copper pillar.
[0076] Optionally, ion beam etching or dry etching is used to etch the top of the first copper pillar along the third opening. The etching depth can be set to a preset depth, for example, 1% to 3% of the height of the first copper pillar.
[0077] Step S303: Based on the third opening, the second photoresist layer is removed to form the second opening.
[0078] In this embodiment, a distributed method for forming the second opening is used. If the second opening is formed in one step, after the second opening is formed, if the top of the first copper pillar is etched, the second photoresist layer located at the edge of the first copper pillar will also be affected, causing this part of the photoresist to be removed, thus affecting the size of the second copper pillar. The distributed opening method avoids the aforementioned situation.
[0079] In this process, a photomask is used to expose the photoresist at the second opening of the first photoresist layer. A developer is then used to remove the exposed photoresist, forming the first opening.
[0080] For example, please refer to Figure 4 Based on the third opening, the second photoresist layer 25 is removed to form the second opening.
[0081] By employing the above technical solution, a smaller third opening is first formed on the second photoresist layer to expose the first copper pillar and etch its top. Then, a second opening is formed based on the third opening through a removal operation. This step-by-step method of forming the second opening allows for more precise control over the size and shape of the opening, ensuring that the top of the first copper pillar is uniformly etched. This provides a flat and clean bonding surface for the subsequent electroplating of the second copper pillar, avoiding alignment errors or uneven etching that may result from directly forming a large opening. This improves the bonding strength and electroplating uniformity of the high-strength copper pillar.
[0082] This application discloses a processing method for a second region. (Refer to...) Figure 5 The method includes: Step S501: Determine the first region and the second region on the first layer of copper pillars. The first region is the projection area of the third opening on the first layer of copper pillars, and the second region is the region other than the first region within the projection area of the second opening on the first layer of copper pillars.
[0083] After the second opening is formed, the first area is etched, which makes the top of the first copper pillar appear as a shape that is low in the middle and high around the edges. However, this shape is not conducive to the implementation of the electroplating process. This is because the opening in the middle part will shield the internal electric field, making it difficult for the electric field lines to penetrate to the bottom. This results in fast deposition around the edges and slow deposition in the middle, which easily forms a "sealing" at the opening and leaves a void inside. Therefore, certain treatments are needed to overcome the aforementioned problems.
[0084] Step S502: Obtain the first height value corresponding to the first region.
[0085] The first height value refers to the shortest distance from the first region to the wafer. For example, a distance sensor is positioned above the wafer. The distance sensor can be used to obtain a first distance value from the distance sensor to the first region, and also a second distance value from the distance sensor to the wafer. The difference between the first distance value and the second distance value is calculated to obtain the first height value.
[0086] Step S503: Obtain the second height value corresponding to the second region.
[0087] The second height value refers to the shortest distance from the second region to the wafer.
[0088] Step S504: Calculate the difference between the first height value and the second height value to obtain the height difference.
[0089] The height difference is the difference between the first height value and the second height value.
[0090] Step S505: If the height difference is greater than the preset height difference threshold, then the second region is etched according to the height difference.
[0091] The height difference threshold is a preset empirical value, which technicians can adjust as needed. When the height difference exceeds the preset threshold, it indicates a noticeable indentation at the top of the first copper pillar, which will significantly impact subsequent electroplating. In some other embodiments, if the height difference is not greater than the preset threshold, the top of the first copper pillar does not exhibit a noticeable indentation, and its impact on electroplating is minimal, thus requiring no etching of the second area.
[0092] Optionally, the inner and outer radii of the second region are obtained. Using the inner and outer radii as the domain and the height difference as a constant, a first processing function is generated. This first processing function describes the relationship between the etching position and the etching depth within the second region and is an increasing function. The second region is then etched according to this first processing function.
[0093] For example, let the inner radius be r1, the outer radius be r2, and the height difference be Δh, then the first processing function is D1=a*(r–R1). 2 Where a = Δh / (r2-r1) 2 D1 represents the etching depth, and r represents the etching position, both expressed in polar coordinates.
[0094] By employing the above technical solution, a first region and a second region on the first layer of copper pillars are identified, a first height value of the first region and a second height value of the second region are obtained, the height difference is calculated, and the second region is etched when the height difference exceeds a preset threshold. This method can detect and compensate for the height non-uniformity at the top of the first layer of copper pillars. Through selective etching, the height of the second region is made consistent with that of the first region, ensuring the flatness of the top of the first layer of copper pillars. This provides a uniform foundation for the subsequent electroplating of the second layer of copper pillars, reduces the height deviation of tall copper pillars, and improves the reliability and performance of the product.
[0095] This application discloses a processing method for a first region. (Refer to...) Figure 6 The method includes: Step S601: Obtain the first height value corresponding to the first region.
[0096] It should be noted that this embodiment is different from... Figure 5 The steps shown in the embodiments are all optional. They can be implemented together or separately.
[0097] The first height value refers to the shortest distance from the first region to the wafer.
[0098] Step S602: Set the deposition thickness distribution according to the first height value.
[0099] Optionally, a second processing function is obtained, which describes the relationship between the deposition location and the ideal height within the first region. An ideal height distribution is generated based on the second processing function. A deposition thickness distribution is then generated according to the ideal deposition thickness distribution and the first height value.
[0100] For example, the second processing function is H_ideal(r) = H_center - b*r 2 Where H_center refers to the ideal height of the center point of the first region, b is a non-negative constant coefficient, and H_ideal(r) is the ideal height at a radius of r.
[0101] Step S603: A copper layer is formed on top of the first copper pillar within the third opening by means of a deposition process, according to the deposition thickness distribution.
[0102] By adopting the above technical solution, a first height value corresponding to the first region is obtained before the second opening is formed. Based on this value, the deposition thickness distribution is set, and a copper layer is formed on the top of the first copper pillar within the third opening through a deposition process. This method allows for selective deposition of a copper layer on the top of the first copper pillar according to the actual height value, compensating for insufficient height and ensuring the top of the first copper pillar reaches the ideal height. This provides a uniform base surface for subsequent electroplating of the second copper pillar, reduces the impact of height deviation on the formation of tall copper pillars, and improves the bonding consistency and overall height accuracy of the copper pillars.
[0103] Based on the same inventive concept, this application provides a high-copper pillar processing system for wafer substrates. Please refer to... Figure 7 The system includes: The acquisition module 701 is used to acquire data related to the above-mentioned high copper pillar processing method for wafer substrates; The memory 702 is used to store the program for the above-described high-copper pillar processing method for wafer substrates; The processor 703 can load and execute the program in the memory to implement the above-described high copper pillar processing method for wafer substrates.
[0104] In summary, a step-by-step electroplating process for forming high copper pillars involves: first, coating a first photoresist layer on the wafer to form a first opening; electroplating the first copper pillar and then removing the photoresist; forming a molding compound to cover the first copper pillar and grinding it to expose it; then coating a second photoresist layer to form a second opening; electroplating the second copper pillar to bond it with the first copper pillar; finally, removing the photoresist, grinding the wafer, and forming a protective layer. This avoids the uniformity issues associated with single-stage electroplating of high copper pillars, improves the height and shape accuracy of the copper pillars, and reduces the tilt angle of the copper pillars.
[0105] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional modules is used as an example. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. The specific working process of the system, device, and unit described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.
[0106] This application provides a computer-readable storage medium storing a computer program that can be loaded by a processor and executed as a method for processing high copper pillars on a wafer substrate.
[0107] Computer storage media include, for example, USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, optical disks, and other media that can store program code.
[0108] Based on the same inventive concept, embodiments of this application provide a smart terminal, including a memory and a processor, wherein the memory stores a computer program that can be loaded by the processor and executed for a high copper pillar processing method of a wafer substrate.
[0109] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional modules is used as an example. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. The specific working process of the system, device, and unit described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.
[0110] The above are all preferred embodiments of this application and are not intended to limit the scope of protection of this application. Any feature disclosed in this specification (including the abstract and drawings) may be replaced by other equivalent or similar features unless specifically stated otherwise. That is, unless specifically stated otherwise, each feature is only one example of a series of equivalent or similar features.
Claims
1. A high copper pillar processing method of a wafer substrate, characterized by, The method comprises the following steps: coating a first photoresist layer on a wafer; forming a first opening at a copper column position of the first photoresist layer; forming a first layer of copper column in the first opening through an electroplating process; removing the first photoresist layer; forming a plastic encapsulation layer on the wafer, so that the plastic encapsulation layer covers the first layer of copper column; grinding the plastic encapsulation layer to expose the first layer of copper column; coating a second photoresist layer on the plastic encapsulation layer; forming a second opening at a copper column position of the second photoresist layer, the second opening exposing the first layer of copper column; forming a second layer of copper column in the second opening through an electroplating process, so that the first layer of copper column and the second layer of copper column are combined into a high copper column; removing the second photoresist layer; grinding the wafer; forming a protective layer on the surface of the high copper column.
2. The high copper pillar processing method of a wafer substrate according to claim 1, wherein, The step of forming a second opening at a copper column position of the second photoresist layer comprises the following steps: forming a third opening at a copper column position of the second photoresist layer, the size of the third opening being smaller than the size of the second opening, and the third opening exposing the first layer of copper column; etching the top of the first layer of copper column along the third opening; removing the second photoresist layer based on the third opening to form the second opening.
3. The high copper pillar processing method of a wafer substrate according to claim 2, wherein, After the step of removing the second photoresist layer based on the third opening to form the second opening, the method further comprises the following steps: determining a first region and a second region on the first layer of copper column, the first region being a projection region of the third opening on the first layer of copper column, and the second region being a region in the projection region of the second opening on the first layer of copper column except the first region; obtaining a first height value corresponding to the first region; obtaining a second height value corresponding to the second region; calculating a difference value between the first height value and the second height value to obtain a height difference value; if the height difference value is greater than a preset height difference threshold value, etching the second region according to the height difference value.
4. The high copper pillar processing method of a wafer substrate according to claim 3, wherein, The second region is in a circular ring shape. The step of etching the second region according to the height difference value comprises the following steps: obtaining an inner radius and an outer radius of the second region; generating a first processing function formula with the inner radius and the outer radius as a definition domain and the height difference value as a constant term, the first processing function formula being used to describe a relationship between an etching position and an etching depth in the second region, and the first processing function formula being an increasing function; etching the second region according to the first processing function formula.
5. The high copper pillar processing method of a wafer substrate according to claim 2, wherein, Before the step of removing the second photoresist layer based on the third opening to form the second opening, the method further comprises the following steps: obtaining a first height value corresponding to the first region; setting a deposition thickness distribution according to the first height value; forming a copper layer on the top of the first layer of copper column in the third opening through a deposition process according to the deposition thickness distribution.
6. The high copper pillar processing method of a wafer substrate according to claim 5, wherein, The first region is in a circular shape. The step of setting a deposition thickness distribution according to the first height value comprises the following steps: obtaining a second processing function, the second processing function being used to describe a relationship between a deposition position and an ideal height in the first region; generating an ideal height distribution according to the second processing function; generating the deposition thickness distribution according to the ideal deposition thickness distribution and the first height value.
7. The high copper pillar processing method of a wafer substrate according to claim 2, wherein, The method further comprises: obtaining a current etching parameter; obtaining a standard etching parameter; adjusting the current etching parameter according to the standard etching parameter when a difference between the current etching parameter and the standard etching parameter is greater than a preset parameter difference.
8. A high copper pillar processing system of a wafer substrate, characterized by, The system is used to execute the high copper pillar processing method of the wafer substrate as claimed in any one of claims 1 to 7, comprising: an obtaining module, used to obtain data related to the high copper pillar processing method of the wafer substrate; a memory, used to store a program of the high copper pillar processing method of the wafer substrate; a processor, the program in the memory being capable of being loaded and executed by the processor and realizing the high copper pillar processing method of the wafer substrate.
9. A smart terminal, characterized by comprising a memory and a processor, the memory storing a computer program capable of being loaded and executed by the processor to execute the method as claimed in any one of claims 1 to 7.
10. A computer-readable storage medium, characterized in that, a computer program capable of being loaded and executed by the processor to execute the method as claimed in any one of claims 1 to 7.