A copper electroplating solution suitable for ultra-deep hole TSV filling and copper electroplating process thereof

Abstract

The present invention discloses a copper electroplating solution suitable for ultra-deep hole TSV filling and a copper electroplating process thereof. The copper electroplating process is pre-treated by vacuum ultrasonic wetting, and then the copper electroplating solution for TSV filling provided by the present invention is used to achieve 100% filling of ultra-deep hole TSV. The TSV electroplating filling solution includes copper methanesulfonate, methanesulfonic acid, copper chloride dihydrate, sodium N,N-dimethyldithiocarbamoylpropanesulfonate, 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol polyoxyethylene ether, sodium dodecyl polyoxyethylene ether sulfate, 4,5,6,7-tetrahydro-6-methyl-2-aminobenzothiazole, and 4,5,6,7-tetrahydrobenzothiazole-6-ketone. The copper plating technology for TSV filling suitable for ultra-deep holes provided by the present invention not only has stable potion performance and a service life of up to 30 days, which is more than 1 times the life of other potions.

Description

Technical Field

[0001] The present invention relates to the technical field of copper electroplating, and in particular to a copper electroplating solution suitable for filling ultra-deep vias (TSVs) and a copper electroplating process thereof. Background Art

[0002] TSV technology is currently the most widely used technology in 3D packaging. Through Silicon Via (TSV) can perform three-dimensional stacked packaging. In advanced packaging, the most suitable wafer-level packaging technology is to lead out electrical signals through vertical interconnection based on TSV technology.

[0003] The key technologies of TSV are vertical interconnection and electrical isolation technology, including the formation of through-holes, the realization of insulating layers and barrier layers, and the filling of conductive materials. Among them, electroplating filling is the key node of the entire TSV process. In order to achieve high integration, many studies have focused on this, but due to yield issues or service life issues, they have not been able to meet the mass production needs of TSV packaging processes for 12-inch wafers. With many domestic companies launching 12-inch TSV three-dimensional integration projects, it is urgent to solve the TSV copper plating technology for ultra-deep holes.

[0004] Patent CN103290438B provides a copper plating solution including 120-300g / L copper salt, 10-200g / L acid, 30-80mg / L chloride ion; 0.001-0.3g / L sulfide; 0.5-10g / L polyoxyether compound; 0.05-5g / L polyethylene glycol; 0.001-0.2g / L quaternary ammonium salt; temperature 10-50°C, current density 0.2-20A / dm2. Although this formula inhibits the growth of copper in the high current density area to a certain extent and improves the uniformity of the coating to a certain extent, there is equal wall growth in blind hole electroplating, resulting in voids.

[0005] Patent CN110541179B, Yao Jihao et al. disclosed a wafer-level packaging super TSV copper interconnect material electroplating solution formula including 100-250g / L of copper sulfate pentahydrate, 40-80g / L of concentrated sulfuric acid, 30-50mg / L of chloride ions, 1-5mg / L of 3-thio-isothiourea propanesulfonic acid inner salt, 50-100mg / L of nonylphenol polyoxyethylene ether, and 40-80mg / L of phenazine dye. The nonylphenol polyoxyethylene ether described in the patent is an organic surfactant, which is easy to produce a large amount of foam, which is not conducive to actual production. Therefore, in order to solve the above problems, the present invention realizes 100% filling of holes with a depth of 300um on a 12-inch wafer by improving the pre-treatment process technology and suitable TSV filling technology, solves the filling of TSV holes with a depth of 300um on a 12-inch wafer, and realizes mass production, thereby meeting the needs of the market. Summary of the invention

[0006] In view of the shortcomings of the above-mentioned technologies, the present invention provides a copper electroplating solution and copper electroplating process suitable for ultra-deep hole TSV filling. Not only does it have the advantages of stable solution performance, 100% filling yield, high filling efficiency, and the ability to achieve ultra-deep hole filling with a maximum depth of 300um, and 100% yield on a 12-inch wafer, but the electroplating time is effectively shortened by more than 1 times compared with other similar solutions.

[0007] To achieve the above object, the present invention provides a copper electroplating process suitable for ultra-deep hole TSV filling, comprising the following specific steps:

[0008] a. Pre-plating treatment: Place the wafer in a sealed chamber and evacuate the wafer hole to achieve a vacuum state. Then, the wetting solution is sucked into the TSV hole through the vacuum negative pressure. At the same time, ultrasonic treatment is performed to achieve full and complete wetting of all TSV holes.

[0009] b. After pre-treatment, the substrate enters the copper electroplating tank, clamps the fixture, sets relevant parameters, and checks that the equipment is correct before copper electroplating.

[0010] Among them, the specific conditions of step a are: ultrasonic power of 300-600W, ultrasonic time of 3-10min. The pretreatment technology provided by the present invention adopts a vacuum method to spray the super wetting agent solution through a negative pressure spray method, so that the water droplets generated during spraying can be smaller than the TSV aperture and enter the TSV hole through a negative pressure method. At the same time, it is to avoid the problem of excessive surface tension of the metal in the hole and a small wetting contact angle.

[0011] The specific conditions of step b are: the water injection method is spraying water under vacuum, and the spraying pressure is 1.5-2.5kg / cm 2 , electroplating current density is 0.5-2.5A / dm 2 By forming the wetting solution into a spray state, it is beneficial to wetting the pores and achieve water saving.

[0012] Among them, the vacuum wetting solution in step b is a composite wetting agent solution, including 30-60 mg / L of 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol polyoxyethylene ether and 30-60 mg / L of sodium dodecyl polyoxyethylene ether sulfate, which are composed of a high-efficiency wetting agent at a mass concentration of 1:1. The wetting agent can effectively reduce the surface tension between the metal copper and water in the TSV hole, and the wetting agent is a neutral reagent and will not attack the limited metal seed layer in the hole. At the same time, in order to ensure 100% wetting effect in the hole, a 300-600W ultrasonic process is used to vibrate the water molecules and discharge the air generated by the combination of water droplets to ensure 100% wetting in the TSV hole on a 12-inch wafer.

[0013] The method comprises the following mass concentrations: 500-700 ml / L of copper methanesulfonate, 100-300 ml / L of methanesulfonic acid, 0.12-0.24 g / L of cupric chloride dihydrate and additive components, and the temperature is 25-35°C.

[0014] The additive components include 10-30 mg / L sodium N,N-dimethyldithiocarbamoylpropane sulfonate, 5-45 mg / L 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol polyoxyethylene ether, 5-45 mg / L sodium dodecyl polyoxyethylene ether sulfate, 30-60 mg / L 4,5,6,7-tetrahydro-6-methyl-2-aminobenzothiazole, and 30-60 mg / L 4,5,6,7-tetrahydrobenzothiazole-6-one.

[0015] The mass concentration ratio of 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol polyoxyethylene ether and sodium dodecyl polyoxyethylene ether sulfate in the additive component is 1:1 when used, which improves the wetting ability during the electroplating process.

[0016] Among them, the mass concentration ratio of 4,5,6,7-tetrahydrobenzothiazol-6-one and 4,5,6,7-tetrahydro-6-methyl-2-aminobenzothiazole in the additive component when used is 1:1, which can greatly improve the filling ability of TSV, obtain efficient leveling inhibitor, realize uniform competitive adsorption on the wafer surface, and realize efficient filling in the hole.

[0017] The beneficial effects of the present invention are as follows: compared with the prior art, the copper electroplating solution and copper electroplating process suitable for ultra-deep hole TSV filling provided by the present invention have the following advantages:

[0018] 1) The TSV electroplating solution has stable performance and can stably mass-produce 12-inch wafers (300um hole depth) for 30 days under the same parameters without changing any process parameters. However, a foreign manufacturer needs to constantly sample and analyze the solution and regularly add the solution during mass production. The process parameters are unstable and need to be fine-tuned according to the production quantity. At the same time, the service life is no more than 14 days.

[0019] 2) The TSV electroplating solution has a high filling yield. Through the pre-treatment process and TSV electroplating filling, the filling yield on 12-inch wafers (300um hole depth) during stable mass production has reached 100%. A foreign manufacturer can only achieve 80-95%, and it is difficult to achieve 100% completely, or only occasionally achieve 100% yield.

[0020] 3) The pretreatment technology provided by the present invention adopts a vacuum method to spray a super wetting agent solution through a negative pressure spray method, so that the water droplets generated during the spraying can be smaller than the TSV aperture and enter the TSV hole through the negative pressure method. At the same time, in order to avoid the problem of excessive surface tension of the metal surface of the water droplets in the hole and a small wetting contact angle, the wetting solution used is a composite wetting agent solution, which is a high-efficiency wetting agent composed of 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol polyoxyethylene ether and sodium dodecyl polyoxyethylene ether sulfate in a mass concentration of 1:1, which can effectively reduce the surface tension of the metal copper and water in the TSV hole, and the wetting agent is a neutral reagent and will not attack the limited metal seed layer in the hole. At the same time, in order to ensure 100% wetting effect in the hole, a 300-600W ultrasonic process is used to vibrate the water molecules and discharge the air generated by the combination of the water droplets, thereby ensuring 100% wetting in the TSV hole on a 12-inch wafer.

[0021] 4) The present invention uses 4,5,6,7-tetrahydro-6-methyl-2-aminobenzothiazole and 4,5,6,7-tetrahydrobenzothiazol-6-one in a ratio of 10:1 to obtain a highly efficient leveling inhibitor, achieve uniform competitive adsorption on the wafer surface, and achieve efficient filling in the hole. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The ultra-deep hole TSV filling diagram is obtained by the electroplating process and copper electroplating solution of the present invention. DETAILED DESCRIPTION

[0023] In order to more clearly describe the present invention, the present invention is further described below through text and drawings. The copper electroplating process and copper electroplating solution provided by the present invention can obtain ultra-deep hole TSV filling. Figure 1 shown.

[0024] To achieve the above object, the present invention provides a copper electroplating process suitable for ultra-deep hole TSV filling, comprising the following specific steps:

[0025] a. Pre-plating treatment: Place the wafer in a sealed chamber and evacuate the wafer hole to achieve a vacuum state. Then, the wetting solution is sucked into the TSV hole through the vacuum negative pressure. At the same time, ultrasonic treatment is performed to achieve full and complete wetting of all TSV holes.

[0026] b. After pre-treatment, the substrate enters the copper electroplating tank, clamps the fixture, sets relevant parameters, and checks that the equipment is correct before copper electroplating.

[0027] In this embodiment, the specific conditions of step a are: ultrasonic power of 300-600W, and ultrasonic time of 3-10min.

[0028] In this embodiment, the specific conditions of step b are: the water injection method is spraying water under vacuum, and the spraying pressure is 1.5-2.5kg / cm 2 , electroplating current density is 0.5-2.5A / dm 2 By forming the wetting solution into a spray state, it is beneficial to wetting the pores and achieve water saving.

[0029] In this embodiment, the vacuum wetting solution in step b is a composite wetting agent solution, including 30-60 mg / L of 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol polyoxyethylene ether and 30-60 mg / L of sodium dodecyl polyoxyethylene ether sulfate, which form a high-efficiency wetting agent in a mass concentration of 1:1.

[0030] In this embodiment, the following mass concentrations are included: copper methanesulfonate is 500-700 ml / L, methanesulfonic acid is 100-300 ml / L, cupric chloride dihydrate is 0.12-0.24 g / L and additive components, and the temperature is 25-35°C.

[0031] In this embodiment, the additive components include 10-30 mg / L of sodium N,N-dimethyldithiocarbamoylpropane sulfonate, 5-45 mg / L of 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol polyoxyethylene ether, 5-45 mg / L of sodium dodecyl polyoxyethylene ether sulfate, 30-60 mg / L of 4,5,6,7-tetrahydro-6-methyl-2-aminobenzothiazole, and 30-60 mg / L of 4,5,6,7-tetrahydrobenzothiazole-6-one.

[0032] In this embodiment, the mass concentration ratio of 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol polyoxyethylene ether and sodium dodecyl polyoxyethylene ether sulfate in the additive component is 1:1 when used, which improves the wetting ability during the electroplating process.

[0033] In this embodiment, the mass concentration ratio of 4,5,6,7-tetrahydrobenzothiazol-6-one and 4,5,6,7-tetrahydro-6-methyl-2-aminobenzothiazole in the additive component is 1:1 when used, which can greatly improve the filling ability of TSV.

[0034] The beneficial effects of the present invention are as follows: compared with the prior art, the copper electroplating solution and copper electroplating process suitable for ultra-deep hole TSV filling provided by the present invention have the following advantages:

[0035] 1) The TSV electroplating solution has stable performance and can stably mass-produce 12-inch wafers (300um hole depth) for 30 days under the same parameters without changing any process parameters. However, a foreign manufacturer needs to constantly sample and analyze the solution and regularly add the solution during mass production. The process parameters are unstable and need to be fine-tuned according to the production quantity. At the same time, the service life is no more than 14 days.

[0036] 2) The TSV electroplating solution has a high filling yield. Through the pre-treatment process and TSV electroplating filling, the filling yield on 12-inch wafers (300um hole depth) during stable mass production has reached 100%. A foreign manufacturer can only achieve 80-95%, and it is difficult to achieve 100% completely, or only occasionally achieve 100% yield.

[0037] 3) The pretreatment technology provided by the present invention adopts a vacuum method to spray a super wetting agent solution through a negative pressure spray method, so that the water droplets generated during the spraying can be smaller than the TSV aperture and enter the TSV hole through the negative pressure method. At the same time, in order to avoid the problem of excessive surface tension of the metal surface of the water droplets in the hole and a small wetting contact angle, the wetting solution used is a composite wetting agent solution, which is a high-efficiency wetting agent composed of 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol polyoxyethylene ether and sodium dodecyl polyoxyethylene ether sulfate in a mass concentration of 1:1, which can effectively reduce the surface tension of the metal copper and water in the TSV hole, and the wetting agent is a neutral reagent and will not attack the limited metal seed layer in the hole. At the same time, in order to ensure 100% wetting effect in the hole, a 300-600W ultrasonic process is used to vibrate the water molecules and discharge the air generated by the combination of the water droplets, thereby ensuring 100% wetting in the TSV hole on a 12-inch wafer.

[0038] 4) The present invention uses 4,5,6,7-tetrahydro-6-methyl-2-aminobenzothiazole and 4,5,6,7-tetrahydrobenzothiazol-6-one in a ratio of 10:1 to obtain a highly efficient leveling inhibitor, achieve uniform competitive adsorption on the wafer surface, and achieve efficient filling in the hole.

[0039] In the following examples and comparative examples, ten substrates of the same type are taken as experimental raw materials for each group of experiments for comparison, and the yield rate is obtained to illustrate the effect.

[0040] Embodiment 1:

[0041] A copper electroplating solution suitable for TSV filling of ultra-deep holes and a copper electroplating process thereof:

[0042] Pretreatment (including ultrasonic)

[0043] Ultrasonic time 7min power 500W

[0044] The vacuum wetting agent solution consists of:

[0045] 2,5,8,11-Tetramethyl-6-dodecyne-5,8-diol polyoxyethylene ether 50mg / L

[0046] Sodium dodecyl polyoxyethylene ether sulfate 50mg / L

[0047] Copper methanesulfonate is 500ml / L, methanesulfonic acid is 100ml / L, copper chloride dihydrate is 0.12g / L, sodium N,N-dimethyldithiocarbamoylpropanesulfonate is 10mg / L, 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol polyoxyethylene ether is 5mg / L, sodium dodecyl polyoxyethylene ether sulfate is 5mg / L, 4,5,6,7-tetrahydro-6-methyl-2-aminobenzothiazole is 30mg / L, 4,5,6,7-tetrahydrobenzothiazol-6-one is 30mg / L, the balance is pure water, the temperature is 30℃, and the current density is 0.5A / dm 2 .

[0048] This test was conducted on a vertical electroplating machine. The final electroplating time was 360 minutes, achieving complete filling of the 300um deep TSV hole on a 12-inch surface. No defects were found in the hole during the full inspection, and the yield rate reached 100%.

[0049] Embodiment 2:

[0050] A copper electroplating solution suitable for TSV filling of ultra-deep holes and a copper electroplating process thereof

[0051] Pretreatment (including ultrasonic)

[0052] Ultrasonic time 7min power 500W

[0053] The vacuum wetting agent solution consists of:

[0054] 2,5,8,11-Tetramethyl-6-dodecyne-5,8-diol polyoxyethylene ether 30mg / L

[0055] Sodium dodecyl polyoxyethylene ether sulfate 30mg / L

[0056] Copper methanesulfonate is 700ml / L, methanesulfonic acid is 300ml / L, copper chloride dihydrate is 0.24g / L, sodium N,N-dimethyldithiocarbamoylpropanesulfonate is 30mg / L, 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol polyoxyethylene ether is 45mg / L, sodium dodecyl polyoxyethylene ether sulfate is 45mg / L, 4,5,6,7-tetrahydro-6-methyl-2-aminobenzothiazole is 60mg / L, 4,5,6,7-tetrahydrobenzothiazol-6-one is 60mg / L, the balance is pure water, the temperature is 30℃, and the current density is 1.5A / dm 2 .

[0057] This test was conducted on a vertical electroplating machine. The final electroplating time was 150 minutes, achieving complete filling of the 300um deep TSV hole on a 12-inch surface. No defects were found in the hole during the full inspection, and the yield rate reached 100%.

[0058] Example 3

[0059] A copper electroplating solution suitable for TSV filling of ultra-deep holes and a copper electroplating process thereof

[0060] Pretreatment (including ultrasonic)

[0061] Ultrasonic time 7min power 500W

[0062] The vacuum wetting agent solution consists of:

[0063] 2,5,8,11-Tetramethyl-6-dodecyne-5,8-diol polyoxyethylene ether 60mg / L

[0064] Sodium dodecyl polyoxyethylene ether sulfate 60mg / L

[0065] Copper methanesulfonate is 600ml / L, methanesulfonic acid is 200ml / L, copper chloride dihydrate is 0.2g / L, sodium N,N-dimethyldithiocarbamoylpropanesulfonate is 20mg / L, 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol polyoxyethylene ether is 30mg / L, sodium dodecyl polyoxyethylene ether sulfate is 30mg / L, 4,5,6,7-tetrahydro-6-methyl-2-aminobenzothiazole is 40mg / L, 4,5,6,7-tetrahydrobenzothiazol-6-one is 40mg / L, the balance is pure water, the temperature is 30℃, and the current density is 2.5A / dm 2 .

[0066] This test was conducted on a vertical electroplating machine. The final electroplating time was 90 minutes, achieving complete filling of the 300um deep TSV hole on a 12-inch surface. No defects were found in the hole during the full inspection, and the yield rate reached 100%.

[0067] Comparative Example 1:

[0068] A copper electroplating solution suitable for TSV filling of ultra-deep holes and a copper electroplating process thereof:

[0069] Pretreatment (excluding ultrasonic)

[0070] The vacuum wetting agent solution consists of:

[0071] 2,5,8,11-Tetramethyl-6-dodecyne-5,8-diol polyoxyethylene ether 50mg / L

[0072] Sodium dodecyl polyoxyethylene ether sulfate 50mg / L

[0073] Copper methanesulfonate is 500ml / L, methanesulfonic acid is 100ml / L, copper chloride dihydrate is 0.12g / L, sodium N,N-dimethyldithiocarbamoylpropanesulfonate is 10mg / L, 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol polyoxyethylene ether is 5mg / L, sodium dodecyl polyoxyethylene ether sulfate is 5mg / L, 4,5,6,7-tetrahydro-6-methyl-2-aminobenzothiazole is 30mg / L, 4,5,6,7-tetrahydrobenzothiazol-6-one is 30mg / L, the balance is pure water, the temperature is 30℃, and the current density is 0.5A / dm 2 .

[0074] This test was a comparative test. Ultrasonic waves were reduced in the pre-treatment. The same parameters were tested on a vertical electroplating machine. The electroplating time was 360 minutes, and the yield was only 20%. Poor wetting at the bottom of a large number of holes caused voids.

[0075] Comparative Example 2

[0076] A copper electroplating solution suitable for TSV filling of ultra-deep holes and a copper electroplating process thereof:

[0077] Pretreatment (including ultrasonic)

[0078] Ultrasonic time 7min power 500W

[0079] Copper methanesulfonate is 500ml / L, methanesulfonic acid is 100ml / L, copper chloride dihydrate is 0.12g / L, sodium N,N-dimethyldithiocarbamoylpropanesulfonate is 10mg / L, 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol polyoxyethylene ether is 5mg / L, sodium dodecyl polyoxyethylene ether sulfate is 5mg / L, 4,5,6,7-tetrahydro-6-methyl-2-aminobenzothiazole is 30mg / L, 4,5,6,7-tetrahydrobenzothiazol-6-one is 30mg / L, the balance is pure water, the temperature is 30℃, and the current density is 0.5A / dm 2 .

[0080] This test is a comparative test. No wetting agent is used in the pre-treatment stage. The same parameters are tested on a vertical electroplating machine. The electroplating time is 360 minutes and the yield is only 50%. There is a high probability of poor wetting leading to voids in some parts, especially in the relatively sparse holes and the center area of ​​the wafer.

[0081] Comparative Example 3

[0082] A copper electroplating solution suitable for TSV filling of ultra-deep holes and a copper electroplating process thereof

[0083] Pretreatment (including ultrasonic)

[0084] Ultrasonic time 7min power 500W

[0085] The vacuum wetting agent solution consists of:

[0086] 2,5,8,11-Tetramethyl-6-dodecyne-5,8-diol polyoxyethylene ether 30mg / L

[0087] Sodium dodecyl polyoxyethylene ether sulfate 30mg / L

[0088] Copper methanesulfonate is 700ml / L, methanesulfonic acid is 300ml / L, copper chloride dihydrate is 0.24g / L, sodium N,N-dimethyldithiocarbamoylpropanesulfonate is 30mg / L, 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol polyoxyethylene ether is 45mg / L, sodium dodecyl polyoxyethylene ether sulfate is 45mg / L, the balance is pure water, the temperature is 30℃, and the current density is 0.5A / dm 2 .

[0089] This test is a comparative test. The plating solution lacks 4,5,6,7-tetrahydro-6-methyl-2-aminobenzothiazole and 4,5,6,7-tetrahydrobenzothiazol-6-one. The same parameters are tested on a vertical electroplating machine. The plating time is 360 minutes and the yield is only about 40%. There is a high probability of poor wetting leading to voids in some parts, especially in the relatively sparse holes and the center area of ​​the wafer.

[0090] Comparative Example 4

[0091] A copper electroplating solution suitable for TSV filling of ultra-deep holes and a copper electroplating process thereof

[0092] Pretreatment (including ultrasonic)

[0093] Ultrasonic time 7min power 500W

[0094] The vacuum wetting agent solution consists of:

[0095] 2,5,8,11-Tetramethyl-6-dodecyne-5,8-diol polyoxyethylene ether 30mg / L

[0096] Sodium dodecyl polyoxyethylene ether sulfate 30mg / L

[0097] Copper methanesulfonate is 700ml / L, methanesulfonic acid is 300ml / L, copper chloride dihydrate is 0.24g / L, sodium N,N-dimethyldithiocarbamoylpropanesulfonate is 30mg / L, the balance is pure water, the temperature is 30℃, and the current density is 0.5A / dm 2 .

[0098] This test was a comparative test. The electroplating solution lacked 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol polyoxyethylene ether and sodium dodecyl polyoxyethylene ether sulfate. The same parameters were tested on a vertical electroplating machine. The electroplating time was 360 minutes, and the yield was only 70%. Poor wetting occurred at the bottom of a large number of holes, resulting in voids.

[0099] The above disclosure is only an embodiment of the present invention, but the present invention is not limited thereto, and any changes that can be conceived by those skilled in the art should fall within the protection scope of the present invention.

Claims

1. A copper electroplating process suitable for ultra-deep hole TSV filling, characterized in that: The specific steps include: a. Pre-plating treatment: Place the wafer in a sealed chamber and evacuate the wafer hole to achieve a vacuum state. Then, the wetting solution is sucked into the TSV hole through the vacuum negative pressure. At the same time, ultrasonic treatment is performed to achieve full and complete wetting of all TSV holes. b. After pretreatment, the substrate enters the copper electroplating tank, clamps the fixture, sets relevant parameters, and checks the equipment for correctness before copper electroplating; The specific conditions of step a are as follows: ultrasonic power of 300-600W, ultrasonic time of 3-10min, negative pressure spraying, spraying pressure of 1.5-2.5kg / cm 2 ; The specific conditions of step b are: the electroplating current density is 0.5-2.5A / dm 2 ; Wherein, the wetting solution in step a comprises 30-60 mg / L of 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol polyoxyethylene ether and 30-60 mg / L of sodium dodecyl polyoxyethylene ether sulfate, and the mass concentration ratio of the two when used is 1:

1.

2. A copper electroplating solution suitable for the copper electroplating process for filling ultra-deep vias TSV according to claim 1, characterized in that: The invention comprises the following mass concentrations: 500-700 ml / L of copper methanesulfonate, 100-300 ml / L of methanesulfonic acid, 0.12-0.24 g / L of cupric chloride dihydrate and additive components; the additive components comprise 10-30 mg / L of sodium N,N-dimethyldithiocarbamoylpropanesulfonate, 5-45 mg / L of 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol polyoxyethylene ether, 5-45 mg / L of sodium dodecyl polyoxyethylene ether sulfate, 30-60 mg / L of 4,5,6,7-tetrahydro-6-methyl-2-aminobenzothiazole and 30-60 mg / L of 4,5,6,7-tetrahydrobenzothiazole-6-one.

3. The copper electroplating solution according to claim 2, characterized in that: The mass concentration ratio of 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol polyoxyethylene ether and sodium dodecyl polyoxyethylene ether sulfate in the additive component when used is 1:

1.

4. The copper electroplating solution according to claim 2, characterized in that: The mass concentration ratio of 4,5,6,7-tetrahydrobenzothiazol-6-one and 4,5,6,7-tetrahydro-6-methyl-2-aminobenzothiazole in the additive component when used is 1:1.

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