Electroplating method for rough copper surfaces and substrates thereof

Abstract

The application provides a rough copper surface electroplating method and a substrate thereof, and the method comprises the following steps: preparing a target substrate, wherein the surface of the target substrate is attached with a first base copper layer; placing the target substrate into an oven for baking; thinning the first base copper layer by using a copper etching stabilizer, and then drilling a target hole in the target substrate; performing sand blasting treatment on the surface of the target substrate by using a horizontal sand blasting device, wherein the sand blasting material of the sand blasting device is corundum; performing high-pressure water washing on the surface of the target substrate, and then electroplating a target copper layer on the surface of the target substrate. According to the technical scheme, the uneven copper surface of the target substrate is rubbed by the corundum of the sand blasting treatment before copper plating, so that the uneven copper surface is lowered, the flatness of the surface of the first base copper layer is improved, the electroplating effect of the target substrate is improved, and the crystallization level of the copper surface of the substrate is improved.

Description

Technical Field

[0001] This invention relates to the field of semiconductor process technology, and in particular to an electroplating method for rough copper surfaces and a substrate thereof. Background Technology

[0002] Electroplating copper is an important step in the substrate manufacturing process. However, the quality of substrates provided by different suppliers varies, especially the roughness of the base copper layer on the substrate surface. If the base copper layer is relatively rough, the surface of the electroplated copper layer is not flat with the surface of the base copper layer, resulting in the crystallization level of the copper surface of the substrate not meeting the requirements. Summary of the Invention

[0003] This invention aims to at least solve one of the technical problems existing in the prior art. To this end, this invention proposes an electroplating method for a rough copper surface and a substrate thereof, which can reduce the influence of the roughness of the base copper layer on the electroplating and improve the crystallinity of the copper surface of the substrate.

[0004] In a first aspect, embodiments of the present invention provide an electroplating method for a rough copper surface, comprising:

[0005] Prepare a target substrate, wherein a first base copper layer is attached to the surface of the target substrate;

[0006] The target substrate is placed in an oven for baking.

[0007] After the first base copper layer is thinned by using a copper etching stabilizer, a target hole is drilled in the target substrate.

[0008] The surface of the target substrate is sandblasted using a horizontal sandblasting device, wherein the sandblasting material of the sandblasting device is corundum.

[0009] After the surface of the target substrate is subjected to high-pressure water washing, a target copper layer is electroplated on the surface of the target substrate.

[0010] According to some embodiments of the present invention, after drilling a target hole in the target substrate, the method further includes:

[0011] The surface of the target substrate and the walls of the target holes are degreased;

[0012] After removing the oxide layer from the surface of the first base copper layer, the target substrate is pre-impregnated.

[0013] A layer of copper is deposited after the copper-plating catalyst is adsorbed on the pore wall of the target pore;

[0014] An organic conductive film is prepared between the hole wall of the target hole and the surface of the target substrate.

[0015] According to some embodiments of the present invention, the number of target substrates is multiple, and a target copper layer is electroplated on the surface of the target substrates, including:

[0016] At least one electroplating test substrate is determined from the plurality of target substrates;

[0017] After performing an electroplating DOE test on the electroplating test substrate, the copper plating lattice of the electroplating test substrate is detected.

[0018] When the copper plating lattice meets the preset crystallization level, the target copper layer is electroplated on the surface of the target substrate according to the electroplating process parameters of the DOE test.

[0019] According to some embodiments of the present invention, after drilling a target hole in the target substrate, the method further includes:

[0020] The height of the first copper particle is determined by detecting the surface roughness of the target substrate. The height of the first copper particle is the height of the surface copper particles of the first base copper layer before sandblasting. The number of surface copper particles is multiple.

[0021] When the maximum height of the first copper particle is greater than the preset height threshold, the target substrate is subjected to sandblasting and high-pressure water washing in sequence, and then the target copper layer is electroplated.

[0022] Alternatively, when the maximum height of the first copper particle is less than the height threshold, the target copper layer is electroplated on the surface of the target substrate.

[0023] According to some embodiments of the present invention, before the surface of the target substrate is sandblasted using a horizontal sandblasting device, the method further includes:

[0024] Prepare a sandblasting test substrate, the surface of which is coated with a second base copper layer.

[0025] The height of the second copper particle is determined by detecting the surface roughness of the sandblasting test substrate. The height of the second copper particle is the height of the surface copper particles of the second base copper layer before the sandblasting process.

[0026] The surface of the test substrate is sandblasted using the horizontal sandblasting equipment, and the target operating parameters for sandblasting the target substrate are determined based on the sandblasting results.

[0027] According to some embodiments of the present invention, determining the target operating parameters for sandblasting the target substrate using the horizontal sandblasting equipment based on the sandblasting results includes:

[0028] The third copper particle height is determined by re-inspecting the surface roughness of the sandblasting test substrate. The third copper particle height is the height of the surface copper particles of the second base copper layer after sandblasting.

[0029] Determine the decrease in copper particle height between the second copper particle height and the third copper particle height, and determine the target operating parameters based on the decrease in copper particle height, the first copper particle height, and the height threshold.

[0030] According to some embodiments of the present invention, the step of sandblasting the surface of the sandblasting test substrate using the horizontal sandblasting equipment, and determining the target operating parameters for sandblasting the target substrate using the horizontal sandblasting equipment based on the sandblasting results, includes:

[0031] The horizontal sandblasting equipment is controlled to perform sandblasting on a first area of ​​the sandblasting test substrate according to a first operating parameter, and the horizontal sandblasting equipment is controlled to perform sandblasting on a second area of ​​the sandblasting test substrate according to a second operating parameter. The sandblasting intensity of the horizontal sandblasting equipment under the first operating parameter is greater than that under the second operating parameter, and the first area and the second area do not overlap.

[0032] The copper particle height decrease value in the first region and the copper particle height decrease value in the second region are determined, and the target operating parameters are determined based on the copper particle height decrease value in the first region, the copper particle height decrease value in the second region, the first copper particle height, and the height threshold.

[0033] According to some embodiments of the present invention, the target operating parameters include a target sandblasting pressure value and a target sandblasting linear velocity, wherein the target sandblasting linear velocity is the linear velocity of the diamond abrasive passing through a horizontal line.

[0034] In a second aspect, embodiments of the present invention provide a substrate, the surface of which includes a first base copper layer and a target copper layer, the target copper layer being obtained by electroplating using an electroplating method for rough copper surfaces as described in the first aspect.

[0035] According to some embodiments of the present invention, the copper plating lattice on the surface of the copper layer formed by the first base copper layer and the target copper layer satisfies a preset crystallization level, wherein the crystallization level is used to indicate the roughness of the copper layer surface.

[0036] An embodiment of the present invention includes: preparing a target substrate, wherein a first base copper layer is attached to the surface of the target substrate; placing the target substrate in a baking machine for baking; thinning the first base copper layer using a copper etching stabilizer, and then drilling target holes in the target substrate; sandblasting the surface of the target substrate using a horizontal sandblasting device, wherein the sandblasting material of the sandblasting device is diamond abrasive; and after high-pressure water washing of the surface of the target substrate, electroplating a target copper layer onto the surface of the target substrate. According to the technical solution of this embodiment, before copper plating, the sandblasted diamond abrasive can rub against the uneven copper surface of the target substrate, causing the uneven copper surface to decrease, improving the smoothness of the first base copper layer surface, improving the electroplating effect of the target substrate, and improving the crystallinity level of the copper surface of the substrate. Attached Figure Description

[0037] Figure 1 This is a flowchart of an electroplating method for a rough copper surface provided in one embodiment of the present invention;

[0038] Figure 2 This is a schematic diagram of a substrate subjected to sandblasting treatment according to another embodiment of the present invention;

[0039] Figure 3 This is an image showing the effect of sandblasting a substrate according to another embodiment of the present invention;

[0040] Figure 4 This is a schematic diagram of the structure after electroplating the target copper layer according to another embodiment of the present invention;

[0041] Figure 5 This is a flowchart of the deposition of chemical copper and pore formation provided in another embodiment of the present invention;

[0042] Figure 6 This is a flowchart of an electroplating target copper layer provided in another embodiment of the present invention;

[0043] Figure 7 This is a flowchart of the process for determining the target copper layer for electroplating provided in another embodiment of the present invention;

[0044] Figure 8 This is a flowchart for determining the target operating parameters of a sandblasting device, provided in another embodiment of the present invention;

[0045] Figure 9 This is a flowchart for determining target operating parameters provided in another embodiment of the present invention;

[0046] Figure 10 This is a flowchart of determining target operating parameters based on the results of different operating parameters, provided in another embodiment of the present invention. Detailed Implementation

[0047] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0048] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0049] In the description of this invention, "several" means one or more, "more than" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0050] This invention provides an electroplating method for rough copper surfaces and a substrate thereof. The method includes: preparing a target substrate, wherein a first base copper layer is attached to the surface of the target substrate; placing the target substrate in a baking machine for baking; thinning the first base copper layer using a copper etching stabilizer, and then drilling target holes in the target substrate; sandblasting the surface of the target substrate using a horizontal sandblasting device, wherein the sandblasting material of the sandblasting device is diamond abrasive; and after high-pressure water washing of the surface of the target substrate, electroplating a target copper layer onto the surface of the target substrate. According to the technical solution of this embodiment, before copper plating, the sandblasted diamond abrasive can be used to rub against the uneven copper surface of the target substrate, thereby reducing the unevenness of the copper surface, improving the smoothness of the first base copper layer surface, improving the electroplating effect of the target substrate, and improving the crystallinity of the copper surface of the substrate.

[0051] In the description of this invention, unless otherwise explicitly defined, terms such as "setting," "installing," and "connecting" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0052] The embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0053] like Figure 1 As shown, Figure 1This is a flowchart of an electroplating method for a rough copper surface according to an embodiment of the present invention. The method includes, but is not limited to, the following steps:

[0054] S1, Prepare a target substrate, wherein a first base copper layer is attached to the surface of the target substrate;

[0055] S2, Place the target substrate into the baking machine for feeding and baking;

[0056] S3, after thinning the first base copper layer with a copper etching stabilizer, drill the target hole in the target substrate;

[0057] S4, The surface of the target substrate is sandblasted using a horizontal sandblasting device, wherein the sandblasting material of the sandblasting device is diamond abrasive;

[0058] S5. After high-pressure water washing of the surface of the target substrate, the target copper layer is electroplated on the surface of the target substrate.

[0059] It should be noted that, as Figure 2 As shown, a first base copper layer 20 is usually attached to the surface of the target substrate 10, which results in a certain grainy texture on the surface of the target substrate 10. Figure 2 The shape and distribution of the first base copper layer 20 shown are merely examples and do not limit the specific shape and structure of the first base copper layer 20.

[0060] It should be noted that the baking tray can eliminate stress on the target substrate, preventing defects such as board bending and warping that affect yield when the target substrate is subjected to stress in subsequent processes; it can also stabilize the size of the target substrate and reduce the expansion and contraction of the target substrate. The baking tray can be completed by equipment such as a baking machine. Those skilled in the art are familiar with how to bake the target substrate, so it will not be repeated here.

[0061] It should be noted that, since a first base copper layer is attached to the surface of the target substrate, in order to ensure that the thickness of the copper layer after electroplating meets the process requirements and facilitates fine line etching, it is necessary to reduce the copper layer through a copper reduction process. For example, copper reduction can be accomplished using a sulfuric acid and hydrogen peroxide system. Under the action of a copper etching stabilizer, the copper layer is thinned. Those skilled in the art are familiar with how to use sulfuric acid and hydrogen peroxide for copper reduction, and will not elaborate further here.

[0062] It should be noted that the target holes obtained by drilling on the target substrate can be through holes or blind holes. They can serve as conductive paths on the copper surface of the target substrate, or as alignment holes or positioning holes for other processes. The specific type of target hole is not limited here.

[0063] Understandably, due to the varying quality of target substrates provided by different manufacturers, it is difficult for metallic copper to extend beyond the top of the first base copper layer during electroplating. The copper particles in the first base copper layer inevitably protrude beyond the electroplated target copper layer. If the first base copper layer of the target substrate is relatively rough, and the copper particles protrude excessively beyond the target copper layer, the surface of the electroplated target substrate can be considered very rough. Specifically, the copper surface crystallization does not meet the required crystallization level, affecting subsequent processes and resulting in a low yield of the target substrate. Therefore, this embodiment uses a horizontal sandblasting device to sandblast the surface of the target substrate, using diamond abrasive to polish the copper particles in the first base copper layer, obtaining a smoother surface. Afterward, high-pressure water washing removes the diamond abrasive, further reducing the height difference between the surface of the target copper layer and the copper particles during electroplating, thus reducing the roughness of the target substrate and improving the crystallization level.

[0064] For example, refer to Figures 2 to 4 The structure of the target substrate is as follows Figure 2 As shown, the target substrate 10 moves horizontally in the horizontal sandblasting equipment, and the diamond abrasive spraying device can spray perpendicularly to the target substrate 10. Due to the copper particles of the first base copper layer 20 ( Figure 2 The triangular structure shown is typically a raised structure. When diamond powder is sprayed onto the first base copper layer, the diamond powder rubs against the sides and top of the copper particles, physically smoothing the copper particles. Figure 2 The structure obtained after sandblasting at the position indicated by the dashed line is as follows: Figure 3 As shown, diamond abrasive 30 is filled into two adjacent polished copper particles. Figure 3 Between the trapezoidal structures shown, it can be seen that the copper particles are effectively reduced in both width and height, that is, the first base copper layer 20 is effectively smoothed, and the roughness is effectively reduced.

[0065] Then, it is washed with high-pressure water. Figure 3 The diamond abrasive 30 shown is used for cleaning to expose the surface of the target substrate, which is then placed in an electroplating apparatus for electroplating of the target copper layer, resulting in the structure shown. Figure 4 As shown, a target copper layer 40 is electroplated on the surface of the target substrate 10 based on the first base copper layer 20. The height difference between the target copper layer 40 and the first base copper layer 20 is small, which can meet the requirements of crystallization level, making subsequent processes more accurate and improving the production yield of the target substrate.

[0066] Additionally, in one embodiment, reference is made to Figure 5 After step S3 is completed, the following steps are included, but are not limited to:

[0067] S31, Degrease the surface of the target substrate and the walls of the target holes;

[0068] S32, after removing the oxide layer on the surface of the first base copper layer, pre-impregnate the target substrate;

[0069] S33, after adsorbing copper-plating catalyst on the pore wall of the target pore, a layer of porous copper is deposited;

[0070] S34, an organic conductive film is prepared between the hole wall of the target hole and the surface of the target substrate.

[0071] It should be noted that since electroplating of the target copper layer is required after sandblasting, necessary processes can be performed on the target holes after drilling. In this embodiment, the processes include degreasing, micro-etching, pre-dip, activation, acceleration, and chemical copper plating. The degreasing process cleans the copper surface of the first base copper layer of the target substrate and also cleans the hole walls, creating a positive charge on the hole walls to adsorb the negatively charged copper plating catalyst in the subsequent activation process. In this embodiment, colloidal palladium is used as the copper plating catalyst. After degreasing the target hole walls, the copper oxide layer can be removed by micro-etching, and water and impurities can be filtered out by pre-dip to prevent them from being introduced into the activation process. The activation process adsorbs colloidal palladium onto the hole walls, and the acceleration process removes the tin compounds from the colloidal palladium to expose the palladium. Finally, the chemical copper plating process, catalyzed by the colloidal palladium, deposits a thin layer of copper as hole copper in the hole walls.

[0072] It should be noted that after obtaining the copper foil in the holes, a hole-forming process can be performed on the target holes to form an organic conductive film on the hole walls and the surface of the target substrate, giving the copper foils on both sides conductive properties. For example, the hole-forming process can sequentially include: micro-etching into the substrate, pressure water washing for PI adjustment, water washing, hole preparation, water jet washing, oxidation, recovery water washing, water jet washing, sponge drying, strong air drying, hot air drying, and board assembly. Pressure water washing for PI adjustment can slightly etch and roughen the PI substrate inside the target holes; hole preparation can clean the hole walls and also adjust them to some extent; oxidation can cause a layer of manganese dioxide to accumulate on the hole walls, thereby undergoing translation under the catalysis of manganese dioxide, forming a manganese reaction between the hole walls and the surface of the target substrate to obtain an organic conductive film.

[0073] In another embodiment, the number of target substrates is multiple, as shown in the reference. Figure 6 Step S5 also includes, but is not limited to, the following steps:

[0074] S51, at least one electroplating test substrate is determined from a plurality of target substrates;

[0075] S52, after performing electroplating DOE test on the electroplating test substrate, detect the copper plating lattice of the electroplating test substrate;

[0076] S53, when the copper plating lattice meets the preset crystallization level, the target copper layer is electroplated on the surface of the target substrate according to the electroplating process parameters of the DOE test.

[0077] It should be noted that during the substrate manufacturing process, multiple target substrates are usually manufactured simultaneously. For target substrates in the same batch, the physical parameters of the first base copper layer are similar, that is, the surface roughness is also similar. Before electroplating, the target substrates that have undergone sandblasting can be subjected to electroplating DOE test to determine the final electroplating process parameters.

[0078] It should be noted that after performing DOE testing on the electroplating test substrate, the copper plating lattice, i.e. the crystallization of the copper surface after copper plating, can be determined by visual inspection. If the copper plating lattice meets the requirements, such as a certain grade, then the same electroplating process parameters can be used for other target substrates.

[0079] It should be noted that the electroplating process parameters may include the type of electroplating solution, the magnitude of the current applied during electroplating, the energizing time, etc., but this embodiment does not impose any limitations on these.

[0080] Additionally, refer to Figure 7 In one embodiment, after performing step S3, the following steps are included, but are not limited to:

[0081] S41, the height of the first copper particle is determined by detecting the surface roughness of the target substrate. The height of the first copper particle is the height of the surface copper particles of the first base copper layer before sandblasting. The number of surface copper particles is multiple.

[0082] S42, when the maximum height of the first copper particle is greater than the preset height threshold, the target substrate is subjected to sandblasting and high-pressure water washing in sequence, and then the target copper layer is electroplated.

[0083] S43, when the maximum height of the first copper particle is less than the height threshold, a target copper layer is electroplated on the surface of the target substrate.

[0084] It should be noted that, due to variations in the quality of substrates from different suppliers or batches, sandblasting involves polishing the first base copper layer. Therefore, it is essential to determine beforehand whether sandblasting is necessary for the target substrate to avoid over-polishing and affecting its yield. Based on this, in this embodiment, after drilling and before sandblasting, the surface roughness of the target substrate is measured to determine the height of the first copper particles (e.g., ...). Figure 2The height of the triangular region shown in the diagram is considered. If the maximum height of the first copper particle (i.e., the tallest copper particle) is higher than the height threshold, the surface of the target substrate is determined to be relatively rough, requiring sandblasting and then copper plating. If the minimum height of the first copper particle is less than the height threshold, the surface roughness of the target substrate is considered to be within the normal range, and electroplating can proceed directly. The height threshold can be set according to the actual process requirements for roughness, and is not specified here.

[0085] Additionally, refer to Figure 8 In one embodiment, before performing step S4, the following steps are included, but are not limited to:

[0086] S61, Prepare the sandblasting test substrate. The surface of the sandblasting test substrate is coated with a second base copper layer.

[0087] S62, the height of the second copper particle is determined by detecting the surface roughness of the sandblasting test substrate. The height of the second copper particle is the height of the surface copper particles of the second base copper layer before the sandblasting process.

[0088] S63, the surface of the test substrate is sandblasted using a horizontal sandblasting device, and the target operating parameters for sandblasting the target substrate are determined based on the sandblasting results.

[0089] It should be noted that since horizontal sandblasting equipment can be set with different target operating parameters, the polishing effect on the copper surface will also be different. According to the description of the above embodiment, the surface roughness of different batches of target substrates is different. Therefore, the same operating parameters cannot be used to sandblast and polish all batches of substrates. Based on this, this embodiment needs to determine the polishing effect of different operating parameters, so as to determine the target operating parameters required for the target substrate, so as to ensure that the surface roughness of the target substrate after sandblasting meets the electroplating requirements.

[0090] It should be noted that, referring to the description of the above embodiments, sandblasting is achieved by friction between diamond abrasive and copper particles, thereby polishing the copper particles, reducing their height and width, and making the surface of the target substrate smoother. When the height and width of the copper particles are different, the degree of friction between the diamond abrasive and the copper particles may not be the same. Therefore, the sandblasting test substrate in this embodiment can be one or more of the target substrates. The test is carried out under similar physical parameters to ensure that the obtained target operating parameters meet the polishing requirements of the target substrate.

[0091] For example, one of the multiple target substrates that have been drilled is selected as the sandblasting test substrate. First, the second copper particle height of the sandblasting test substrate is determined by the detection equipment. After sandblasting with preset operating parameters, the descent height of the copper particles is determined according to the sandblasting results. If the descent height meets the polishing requirements of the target substrate, the current operating parameters can be determined as the target operating parameters.

[0092] Additionally, refer to Figure 9 In one embodiment, step S63 further includes, but is not limited to, the following steps:

[0093] S631, the height of the third copper particle is determined by re-inspecting the surface roughness of the sandblasted test substrate. The height of the third copper particle is the height of the surface copper particles of the second base copper layer after sandblasting.

[0094] S632, determine the decrease in copper particle height between the second copper particle height and the third copper particle height, and determine the target operating parameters based on the decrease in copper particle height, the first copper particle height, and the height threshold.

[0095] It should be noted that, according to the description of the above embodiments, when the sandblasting result obtained after sandblasting the test substrate meets the electroplating requirements, the current operating parameters of the horizontal sandblasting equipment can be determined as the target operating parameters. However, if the sandblasting result obtained after sandblasting still fails to meet the electroplating requirements, it may be due to insufficient pressure or linear velocity of the diamond abrasive, resulting in a smaller drop height of the copper particles. Based on this, in this embodiment, given the known height of the second copper particle on the test substrate before sandblasting, the height of the third copper particle is determined after the test sandblasting is completed, and then the drop value of the copper particle height is determined. Since the height of the first copper particle is known, and the height threshold is also known, the required grinding height can be determined based on the height threshold and the first copper particle height. Then, based on the drop value of the copper particle height and the current operating parameters, the target operating parameters are determined by proportional conversion. For example, if the drop value of the copper particle height is half of the required grinding height, the current operating parameters can be adjusted proportionally to double the grinding effect, thereby determining the target operating parameters.

[0096] Additionally, refer to Figure 10 In one embodiment, step S43 further includes, but is not limited to, the following steps:

[0097] S633, according to the first operating parameters, the horizontal sandblasting equipment is controlled to sandblast the first area of ​​the sandblasting test substrate, and according to the second operating parameters, the horizontal sandblasting equipment is controlled to sandblast the second area of ​​the sandblasting test substrate, wherein the sandblasting intensity of the horizontal sandblasting equipment under the first operating parameters is greater than the sandblasting intensity under the second operating parameters, and the first area and the second area do not overlap.

[0098] S634, determine the copper particle height drop value in the first region and the copper particle height drop value in the second region, and determine the target operating parameters based on the copper particle height drop value in the first region, the copper particle height drop value in the second region, the first copper particle height, and the height threshold.

[0099] It should be noted that, according to the description of the above embodiments, if the sandblasting effect of the tested sandblasting treatment cannot meet the electroplating requirements, further testing or analysis is needed to determine the target operating parameters. Based on this, this embodiment performs sandblasting treatment on at least two regions on the sandblasting test substrate. For example, as described above, the sandblasting test substrate is divided into a first region and a second region. When using a horizontal sandblasting device, the front half of the sandblasting test substrate in the horizontal direction can be used as the first region, and the rear half as the second region. After the sandblasting test substrate is moved by the horizontal sandblasting device, it is moved halfway with the first operating parameter, and then switched to the second operating parameter to move the other half, thereby achieving sandblasting treatment with different parameters for two different regions. Of course, the above method is only an example. It is also possible to divide the sandblasting test substrate into upper and lower halves according to actual needs, and achieve sandblasting with different parameters for different regions by blocking one half and sandblasting the other half. Alternatively, the sandblasting test substrate can be divided into multiple regions, which can be adjusted according to the testing requirements.

[0100] It should be noted that after determining the sandblasting results of the first and second regions, the decrease in copper particle height in the first and second regions is determined respectively. According to the description in the above embodiment, when the first copper particle height and the height threshold are known, the difference between the decrease in copper particle height in the first and second regions is used to determine how much more is needed under the current operating parameters to meet the height threshold. For example, if the intensity of the first operating parameter is half the intensity of the second operating parameter, and the decrease in copper particle height in the first region is 50% of the decrease in copper particle height in the second region, and the difference between the first copper particle height and the height threshold is four times the decrease in copper particle height in the first region, then the operating parameter corresponding to four times the intensity of the first operating parameter can be used as the target operating parameter. Of course, the above is only an example. Given the different polishing effects brought about by different parameters, those skilled in the art are motivated to calculate the target operating parameters based on the actual hardware capabilities of the equipment; this will not be elaborated upon here.

[0101] In another embodiment, the target operating parameters include the target sandblasting pressure value and the target sandblasting linear velocity, wherein the target sandblasting linear velocity is the linear velocity of the diamond abrasive passing through a horizontal line.

[0102] It should be noted that the target sandblasting pressure value is used to characterize the ejection pressure of the diamond abrasive, and the target sandblasting linear velocity is the linear velocity of the diamond abrasive across the horizontal line. The specific values ​​can be determined according to the method in the above embodiment. For example, the target sandblasting pressure value can be 1.8 kg / cm², and the target sandblasting linear velocity can be 1.8 m / min.

[0103] In addition, embodiments of the present invention also provide a substrate, see reference. Figure 4 The surface of the substrate 10 includes a first base copper layer 20 and a target copper layer 40, which is obtained by electroplating a rough copper surface.

[0104] It should be noted that by performing electroplating on a rough copper surface in the manner described in the above embodiments, the rough copper surface can be polished by sandblasting, which reduces the particle height of the first base copper layer 20, making the target copper layer 40 of electroplating closer to the surface height of the copper particles, effectively reducing the graininess of the copper surface after electroplating and improving the grade of the copper plating lattice.

[0105] In another embodiment, the copper plating lattice on the surface of the copper layer formed by the first base copper layer and the target copper layer satisfies a preset crystallization level, which is used to indicate the roughness of the copper layer surface.

[0106] It should be noted that before electroplating the target copper layer, the target operating parameters of the horizontal sandblasting equipment can be determined according to the method described in the above embodiments, so that the sandblasting effect meets the electroplating requirements, thereby making the surface of the copper layer formed by the electroplated target copper layer and the first base copper layer smoother, that is, the copper plating lattice on the surface of the copper layer meets the preset crystallization level. The detection method of the copper plating lattice is a technology well known to those skilled in the art, for example, it can be determined by visual inspection, which will not be elaborated here.

[0107] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the embodiments disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein.

[0108] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

[0109] The above provides a detailed description of the preferred embodiments of the present invention. However, the present invention is not limited to the above embodiments. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention. All such equivalent modifications or substitutions are included within the scope defined by the claims of the present invention.

Claims

1. A method for electroplating a rough copper surface, characterized in that, include, Prepare a target substrate, wherein a first base copper layer is attached to the surface of the target substrate; The target substrate is placed in an oven for baking. After the first base copper layer is thinned by using a copper etching stabilizer, a target hole is drilled in the target substrate. The surface of the target substrate is sandblasted using a horizontal sandblasting device, wherein the sandblasting material of the sandblasting device is corundum. After the surface of the target substrate is subjected to high-pressure water washing, a target copper layer is electroplated on the surface of the target substrate. After drilling the target hole in the target substrate, the method further includes: The height of the first copper particle is determined by detecting the surface roughness of the target substrate. The height of the first copper particle is the height of the surface copper particles of the first base copper layer before sandblasting. The number of surface copper particles is multiple. When the maximum height of the first copper particle is greater than the preset height threshold, the target substrate is subjected to sandblasting and high-pressure water washing in sequence, and then the target copper layer is electroplated. Alternatively, when the maximum height of the first copper particle is less than the height threshold, the target copper layer is electroplated on the surface of the target substrate.

2. The electroplating method for rough copper surfaces according to claim 1, characterized in that, After drilling the target hole in the target substrate, the method further includes: The surface of the target substrate and the walls of the target holes are degreased; After removing the oxide layer from the surface of the first base copper layer, the target substrate is pre-impregnated. A layer of copper is deposited after the copper-plating catalyst is adsorbed on the pore wall of the target pore; An organic conductive film is prepared between the hole wall of the target hole and the surface of the target substrate.

3. The electroplating method for rough copper surfaces according to claim 1, characterized in that, The number of target substrates is multiple, and a target copper layer is electroplated on the surface of the target substrates, including: At least one electroplating test substrate is determined from the plurality of target substrates; After performing an electroplating DOE test on the electroplating test substrate, the copper plating lattice of the electroplating test substrate is detected. When the copper plating lattice meets the preset crystallization level, the target copper layer is electroplated on the surface of the target substrate according to the electroplating process parameters of the DOE test.

4. The electroplating method for rough copper surfaces according to claim 1, characterized in that, Before the surface of the target substrate is sandblasted using a horizontal sandblasting device, the method further includes: Prepare a sandblasting test substrate, the surface of which is coated with a second base copper layer. The height of the second copper particle is determined by detecting the surface roughness of the sandblasting test substrate. The height of the second copper particle is the height of the surface copper particles of the second base copper layer before the sandblasting process. The surface of the test substrate is sandblasted using the horizontal sandblasting equipment, and the target operating parameters for sandblasting the target substrate are determined based on the sandblasting results.

5. The electroplating method for rough copper surfaces according to claim 4, characterized in that, The step of determining the target operating parameters for sandblasting the target substrate using the horizontal sandblasting equipment based on the sandblasting results includes: The third copper particle height is determined by re-inspecting the surface roughness of the sandblasting test substrate. The third copper particle height is the height of the surface copper particles of the second base copper layer after sandblasting. Determine the decrease in copper particle height between the second copper particle height and the third copper particle height, and determine the target operating parameters based on the decrease in copper particle height, the first copper particle height, and the height threshold.

6. The electroplating method for rough copper surfaces according to claim 5, characterized in that, The process of sandblasting the surface of the test substrate using the horizontal sandblasting equipment, and determining the target operating parameters for sandblasting the target substrate using the horizontal sandblasting equipment based on the sandblasting results, includes: The horizontal sandblasting equipment is controlled to perform sandblasting on a first area of ​​the sandblasting test substrate according to a first operating parameter, and the horizontal sandblasting equipment is controlled to perform sandblasting on a second area of ​​the sandblasting test substrate according to a second operating parameter. The sandblasting intensity of the horizontal sandblasting equipment under the first operating parameter is greater than that under the second operating parameter, and the first area and the second area do not overlap. The copper particle height decrease value in the first region and the copper particle height decrease value in the second region are determined, and the target operating parameters are determined based on the copper particle height decrease value in the first region, the copper particle height decrease value in the second region, the first copper particle height, and the height threshold.

7. The electroplating method for a rough copper surface according to any one of claims 4 to 6, characterized in that, The target operating parameters include the target sandblasting pressure value and the target sandblasting linear velocity, wherein the target sandblasting linear velocity is the linear velocity of the diamond abrasive passing through a horizontal line.

8. A substrate, characterized in that, The surface of the substrate includes a first base copper layer and a target copper layer, wherein the target copper layer is obtained by electroplating using the method for plating rough copper surfaces as described in any one of claims 1 to 7.

9. A substrate according to claim 8, characterized in that, The copper lattice on the surface of the copper layer formed by the first base copper layer and the target copper layer satisfies a preset crystallization level, which is used to indicate the roughness of the copper layer surface.

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