A kind of HDI board hole filling copper plating liquid composition

Abstract

The invention discloses a HDI board hole-filling copper plating liquid composition, which belongs to the technical field of electroplating. The composition comprises a hole-filling copper plating liquid base liquid, a leveling agent, a brightener and a wetting agent. When VCP (vertical continuous plating) is used to copper-plate a blind hole substrate of an HDI board, the plated board has a high hole-filling rate, a low depression value, a low hole-filling defect rate, a high hole-filling efficiency, and excellent all-plating ability and through-hole deep plating ability. The copper-plated surface has excellent ductility, forms a smooth and bright surface, and the plating layer is stress-free.

Description

Technical Field

[0001] The invention relates to the technical field of electroplating, and in particular to a HDI board hole-filling copper plating liquid composition. Background Art

[0002] HDI is the abbreviation of High Density Interconnector, which is a technology for producing printed circuit boards. It is a circuit board with a relatively high line distribution density using micro blind buried hole technology. HDI is a compact product designed for small-capacity users. Usually, the manufacturing process of HDI boards requires that the blind holes that have been chemically copper-plated be filled by electroplating copper. The advantages of electroplating filling holes are: (1) It is conducive to the design of stacked holes and holes on the disk; (2) It improves electrical performance and helps high-frequency design; (3) It helps heat dissipation; (4) Hole plugging and electrical interconnection are completed in one step; (5) The blind holes are filled with electroplated copper, which has higher reliability and better conductivity than conductive glue.

[0003] The prior art hole filling copper plating scheme is: adding a leveling agent, a brightener and a wetting agent to the hole filling copper plating basic working solution, and copper plating is performed on the blind hole with a blind hole dielectric layer thickness of 40-100μm at a cathode current density of 1.0-2.5ASD. It is required that the blind hole be almost filled or filled to a depression value of less than 10μm (the lower the better) within a certain period of electroplating time. While the hole filling copper plating is being performed, the board surface is also being copper plated. Finally, after the electroplating is completed, while the hole filling depression value is met, the lower the plated copper thickness is, the better. Therefore, a hole filling copper plating additive with excellent performance is required to make the hole filling copper plating more efficient, and the physical properties of the copper plating layer can meet the requirements, and the deep plating ability of the hole filling copper plating is excellent.

[0004] The copper plating additives for hole filling in the prior art have the following shortcomings during use:

[0005] 1. The hole filling efficiency is not high, resulting in a high hole filling electroplating cost. To achieve a qualified hole filling rate, a larger current and a longer electroplating time are required, making the copper plating on the board thicker, resulting in a large amount of unnecessary consumption of copper raw materials;

[0006] 2. While filling the holes with electroplating, there are still some holes on the board for through-hole electroplating. When through-hole electroplating is performed, the hole mouth will be somewhat thin and sharpened, which reduces the reliability of the through-hole;

[0007] 3. When filling the hole with electroplating, the deep plating ability of the through hole on the board is low, which affects the reliability of the entire board

[0008] 4. Occasionally, certain hole filling defects may occur, which will have a certain impact on quality stability. Summary of the invention

[0009] The embodiment of the present invention provides a HDI board hole filling copper plating liquid composition to solve the technical problems existing in the use of the above-mentioned hole filling copper plating additive. The specific contents of the present invention are as follows:

[0010] The object of the present invention is to provide a HDI board hole-filling copper plating solution composition, comprising a hole-filling copper plating solution base liquid, a leveling agent, a brightener and a wetting agent, and the technical point thereof is:

[0011] The leveling agent comprises 1-2% (v / v) polyether, 0.1-0.5% (w / v) polyethylene glycol 20000, 2-3% (v / v) leveling aid, 0.4-0.6% (v / v) sulfuric acid, 0.3-0.6% (v / v) formaldehyde, 0.2-0.3% (w / v) gallstone, and 93-96% (v / v) deionized water;

[0012] The brightener comprises 1-2% (v / v) polyether, 0.1-0.5% (w / v) polyethylene glycol 20000, 0.1-0.5% (v / v) sodium polydisulfide dipropane sulfonate, 0.4-0.6% (v / v) sulfuric acid, 0.3-0.6% (v / v) formaldehyde, 0.2-0.3% (w / v) gallstone, and 95.5-97.9% (v / v) deionized water;

[0013] The wetting agent comprises 12-20% (v / v) polyether, 2-5% (w / v) polyethylene glycol 20000, 0.4-0.6% (v / v) sulfuric acid, 0.4-0.6% (v / v) formaldehyde, 0.2-0.3% (w / v) gallstone, and 73.5-85% (v / v) deionized water.

[0014] In some embodiments of the present invention, in the above-mentioned HDI board hole filling copper plating solution composition, the preparation method of the leveling agent is:

[0015] a. Add deionized water to the reactor, start stirring, slowly add sulfuric acid and stir evenly;

[0016] b. Add polyether, polyethylene glycol 20000 and leveling agent to the reactor in sequence and stir until completely dissolved;

[0017] c. Add formaldehyde to the reactor and stir evenly;

[0018] d. Add gallstones to the reaction kettle and stir until completely dissolved and uniformly dissolved to obtain the leveling agent.

[0019] In some embodiments of the present invention, in the above-mentioned HDI board hole filling copper plating solution composition, the preparation method of the brightener is:

[0020] a. Add deionized water to the reactor, start stirring, slowly add sulfuric acid and stir evenly;

[0021] b. Sequentially add polyether, polyethylene glycol 20000, and sodium polydisulfide propane sulfonate to the reactor and stir until completely dissolved;

[0022] c. Add formaldehyde to the reactor and stir evenly;

[0023] d. Add gallstones to the reaction kettle and stir until completely dissolved and uniformly dissolved to obtain the brightener.

[0024] In some embodiments of the present invention, in the above-mentioned HDI board hole filling copper plating liquid composition, the preparation method of the wetting agent is:

[0025] a. Add deionized water to the reactor, start stirring, slowly add sulfuric acid and stir evenly;

[0026] b. Sequentially add polyether and polyethylene glycol 20000 to the reactor and stir until completely dissolved;

[0027] c. Add formaldehyde to the reactor and stir evenly;

[0028] d. Add gallstones to the reaction kettle and stir until completely dissolved and uniformly dissolved to obtain the brightener.

[0029] In some embodiments of the present invention, in the above-mentioned HDI board hole filling copper plating solution composition, the hole filling copper plating solution base solution includes 30-50 g / L sulfuric acid, 200-250 g / L copper sulfate and 30-70 ppm chloride ions.

[0030] In some embodiments of the present invention, in the above HDI board hole filling copper plating solution composition, the added amount of the leveler is 15-25 mL / L.

[0031] In some embodiments of the present invention, in the above-mentioned HDI board hole filling copper plating solution composition, the added amount of the brightener is 1-2 mL / L.

[0032] In some embodiments of the present invention, in the above HDI board hole filling copper plating solution composition, the added amount of the wetting agent is 10-20 mL / L.

[0033] In some embodiments of the present invention, in the above-mentioned HDI board hole filling copper plating solution composition, the polyether is any one of propylene glycol block polyether, polyether F-6, polyether NPE-108, polyether NPE-105 and random polyether.

[0034] In some embodiments of the present invention, in the above-mentioned HDI board hole filling copper plating solution composition, the leveling auxiliary agent is butynediol diethoxy ether.

[0035] Compared with the prior art, the HDI board hole filling copper plating solution composition of the present invention has the following beneficial effects:

[0036] The HDI board hole filling copper plating liquid composition of the present invention comprises a hole filling copper plating liquid base liquid (30-50 g / L sulfuric acid, 200-250 g / L copper sulfate and 30-70 ppm chloride ions), a leveling agent (1-2% (v / v) polyether, 0.1-0.5% (w / v) polyethylene glycol 20000, 2-3% (v / v) leveling aid, 0.4-0.6% ( v / v) sulfuric acid, 0.3-0.6% (v / v) formaldehyde, 0.2-0.3% (w / v) gallstone, 93-96% (v / v) deionized water), brightener (1-2% (v / v) polyether, 0.1-0.5% (w / v) polyethylene glycol 20000, 0.1-0.5% (v / v) sodium polydisulfide dipropane sulfonate, 0.4-0.6% (v / v) / v) sulfuric acid, 0.3-0.6% (v / v) formaldehyde, 0.2-0.3% (w / v) gallstone, 95.5-97.9% (v / v) deionized water) and wetting agents (12-20% (v / v) polyether, 2-5% (w / v) polyethylene glycol 20000, 0.4-0.6% (v / v) sulfuric acid, 0.4-0.6% (v / v) formaldehyde When copper is plated on blind hole substrate of HDI board by VCP (vertical continuous plating), the plated board has high hole filling rate, low depression value, low hole filling defect rate, high hole filling efficiency, excellent all-plating ability and through-hole deep plating ability, and the copper-plated surface has excellent ductility, forming a smooth and bright surface, and the plating layer is stress-free. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0038] Figure 1 The HDI board hole filling copper plating process of the present invention;

[0039] Figure 2 This is a SEM image of electroplating using the HDI board hole-filling copper plating solution in Example 1 (blind hole board with a hole depth of 75 μm and a hole diameter of 110 μm);

[0040] Figure 3 It is a schematic diagram for calculating the filling rate and the concave value;

[0041] Figure 4 Schematic diagram of hole filling defect;

[0042] Figure 5This is a schematic diagram of electroplating uniformity calculation;

[0043] Figure 6 Schematic diagram of deep capability TP calculation. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0045] The technical solutions provided by various embodiments of the present invention are described in detail below in conjunction with the accompanying drawings.

[0046] Example 1

[0047] The embodiment of the present invention provides a HDI board hole filling copper plating liquid composition to solve the technical problems existing in the use of the above-mentioned hole filling copper plating additive. The specific contents of the present invention are as follows:

[0048] A HDI board hole-filling copper plating liquid composition, comprising

[0049] 40g / L sulfuric acid;

[0050] 225 g / L copper sulfate;

[0051] 50ppm chloride ion;

[0052] 10mL / L leveling agent: including 1.5% (v / v) propylene glycol block polyether (F38), 0.3% (w / v) polyethylene glycol 20000, 2.5% (v / v) butynediol diethoxy ether, 0.5% (v / v) sulfuric acid, 0.45% (v / v) formaldehyde, 0.25% (w / v) gallstone, 94.5% (v / v) deionized water; the preparation method of the leveling agent is:

[0053] a. Add deionized water to the reactor, start stirring, slowly add sulfuric acid and stir evenly;

[0054] b. Sequentially add propylene glycol block polyether (F38), polyethylene glycol 20000, butynediol diethoxy ether to the reactor and stir until completely dissolved;

[0055] c. Add formaldehyde to the reactor and stir evenly;

[0056] d. Add gallstones to the reaction kettle and stir until completely dissolved and uniformly dissolved to obtain the leveling agent.

[0057] 1.5mL / L brightener: comprising 1.5% (v / v) propylene glycol block polyether (F38), 0.3% (w / v) polyethylene glycol 20000, 0.3% (v / v) sodium polydisulfide dipropane sulfonate, 0.5% (v / v) sulfuric acid, 0.45% (v / v) formaldehyde, 0.25% (w / v) gallstone, and 96.7% (v / v) deionized water; the preparation method of the brightener is as follows:

[0058] a. Add deionized water to the reactor, start stirring, slowly add sulfuric acid and stir evenly;

[0059] b. Sequentially add propylene glycol block polyether (F38), polyethylene glycol 20000, and sodium polydisulfide propane sulfonate to the reactor and stir until completely dissolved;

[0060] c. Add formaldehyde to the reactor and stir evenly;

[0061] d. Add gallstones to the reaction kettle and stir until completely dissolved and uniformly dissolved to obtain the brightener.

[0062] 15mL / L wetting agent: including 16% (v / v) propylene glycol block polyether (F38), 3.5% (w / v) polyethylene glycol 20000, 0.5% (v / v) sulfuric acid, 0.5% (v / v) formaldehyde, 0.25% (w / v) gallstone, 79.25% (v / v) deionized water. The preparation method of the wetting agent is:

[0063] a. Add deionized water to the reactor, start stirring, slowly add sulfuric acid and stir evenly;

[0064] b. Sequentially add propylene glycol block polyether (F38) and polyethylene glycol 20000 to the reactor and stir until completely dissolved;

[0065] c. Add formaldehyde to the reactor and stir evenly;

[0066] d. Add gallstones to the reaction kettle and stir until completely dissolved and uniformly dissolved to obtain the brightener.

[0067] Example 2

[0068] The embodiment of the present invention provides a HDI board hole filling copper plating liquid composition to solve the technical problems existing in the use of the above-mentioned hole filling copper plating additive. The specific contents of the present invention are as follows:

[0069] A HDI board hole-filling copper plating liquid composition, comprising

[0070] 30g / L sulfuric acid;

[0071] 200g / L copper sulfate;

[0072] 30ppm chloride ion;

[0073] 15mL / L leveling agent: including 1% (v / v) polyether NPE-108, 0.1% (w / v) polyethylene glycol 20000, 2% (v / v) butynediol diethoxy ether, 0.4% (v / v) sulfuric acid, 0.3% (v / v) formaldehyde, 0.2% (w / v) gallstone, 96% (v / v) deionized water; the preparation method of the leveling agent is:

[0074] a. Add deionized water to the reactor, start stirring, slowly add sulfuric acid and stir evenly;

[0075] b. Sequentially add polyether NPE-108, polyethylene glycol 20000, butynediol diethoxy ether to the reactor and stir until completely dissolved;

[0076] c. Add formaldehyde to the reactor and stir evenly;

[0077] d. Add gallstones to the reaction kettle and stir until completely dissolved and uniformly dissolved to obtain the leveling agent.

[0078] 1mL / L brightener: including 1% (v / v) polyether NPE-108, 0.1% (w / v) polyethylene glycol 20000, 0.1% (v / v) sodium polydisulfide propane sulfonate, 0.4% (v / v) sulfuric acid, 0.3% (v / v) formaldehyde, 0.2% (w / v) gallstone, 97.9% (v / v) deionized water; the preparation method of the brightener is:

[0079] a. Add deionized water to the reactor, start stirring, slowly add sulfuric acid and stir evenly;

[0080] b. Sequentially add polyether NPE-108, polyethylene glycol 20000, and sodium polydisulfide propane sulfonate to the reactor and stir until completely dissolved;

[0081] c. Add formaldehyde to the reactor and stir evenly;

[0082] d. Add gallstones to the reaction kettle and stir until completely dissolved and uniformly dissolved to obtain the brightener.

[0083] 10mL / L wetting agent: including 12% (v / v) polyether NPE-108, 2% (w / v) polyethylene glycol 20000, 0.4% (v / v) sulfuric acid, 0.4% (v / v) formaldehyde, 0.2% (w / v) gallstone, 85% (v / v) deionized water. The preparation method of the wetting agent is:

[0084] a. Add deionized water to the reactor, start stirring, slowly add sulfuric acid and stir evenly;

[0085] b. Add polyether NPE-108 and polyethylene glycol 20000 to the reactor in sequence and stir until completely dissolved;

[0086] c. Add formaldehyde to the reactor and stir evenly;

[0087] d. Add gallstones to the reaction kettle and stir until completely dissolved and uniformly dissolved to obtain the brightener.

[0088] Example 3

[0089] The embodiment of the present invention provides a HDI board hole filling copper plating liquid composition to solve the technical problems existing in the use of the above-mentioned hole filling copper plating additive. The specific contents of the present invention are as follows:

[0090] A HDI board hole-filling copper plating liquid composition, comprising

[0091] 50g / L sulfuric acid;

[0092] 250g / L copper sulfate;

[0093] 70 ppm of chloride ion;

[0094] 25mL / L leveling agent: including 2% (v / v) polyether NPE-105, 0.5% (w / v) polyethylene glycol 20000, 3% (v / v) butynediol diethoxy ether, 0.6% (v / v) sulfuric acid, 0.6% (v / v) formaldehyde, 0.3% (w / v) gallstone, 93% (v / v) deionized water; the preparation method of the leveling agent is:

[0095] a. Add deionized water to the reactor, start stirring, slowly add sulfuric acid and stir evenly;

[0096] b. Sequentially add polyether NPE-105, polyethylene glycol 20000, butynediol diethoxy ether to the reactor and stir until completely dissolved;

[0097] c. Add formaldehyde to the reactor and stir evenly;

[0098] d. Add gallstones to the reaction kettle and stir until completely dissolved and uniformly dissolved to obtain the leveling agent.

[0099] 2mL / L brightener: including 2% (v / v) polyether NPE-105, 0.5% (w / v) polyethylene glycol 20000, 0.5% (v / v) sodium polydisulfide dipropane sulfonate, 0.6% (v / v) sulfuric acid, 0.6% (v / v) formaldehyde, 0.3% (w / v) gallstone, 95.5% (v / v) deionized water; the preparation method of the brightener is:

[0100] a. Add deionized water to the reactor, start stirring, slowly add sulfuric acid and stir evenly;

[0101] b. Sequentially add polyether NPE-105, polyethylene glycol 20000, and sodium polydisulfide propane sulfonate to the reactor and stir until completely dissolved;

[0102] c. Add formaldehyde to the reactor and stir evenly;

[0103] d. Add gallstones to the reaction kettle and stir until completely dissolved and uniformly dissolved to obtain the brightener.

[0104] 20mL / L wetting agent: including 20% ​​(v / v) polyether NPE-105, 5% (w / v) polyethylene glycol 20000, 0.6% (v / v) sulfuric acid, 0.6% (v / v) formaldehyde, 0.3% (w / v) gallstone, 73.5% (v / v) deionized water; the preparation method of the wetting agent is:

[0105] a. Add deionized water to the reactor, start stirring, slowly add sulfuric acid and stir evenly;

[0106] b. Add polyether NPE-105 and polyethylene glycol 20000 to the reactor in sequence and stir until completely dissolved;

[0107] c. Add formaldehyde to the reactor and stir evenly;

[0108] d. Add gallstones to the reaction kettle and stir until completely dissolved and uniformly dissolved to obtain the brightener.

[0109] Test example

[0110] The HDI board hole filling copper plating additive of the present invention is compared with a famous American brand additive, which is replaced by code J, and a domestic brand additive, which is replaced by code B, for all-round performance comparison. The specific sample preparation is as follows: 25 PCB substrates with holes drilled, 5 boards of each additive are used as test boards, and the average value of each test result is taken. The board thickness is 1.2mm, the minimum aperture of the through hole is 0.225mm, and the thickness-to-diameter ratio of the through hole is 5.3:1; the blind hole has a depth of 60μm, an aperture of 100μm, a substrate copper thickness of 14μm, a size of 603mm*518mm, a current density of 1.2ASD, and an electroplating time of 50min. The specific process is shown in General Cao Figure 1 , the test results are shown in the following table:

[0111]

[0112] The industry standard requirements for the test items are as follows: bright and smooth appearance, no copper particles; no or very few hole filling defects; the higher the hole filling rate, the better; the smaller the hole filling depression value, the better; COV≦5%: the smaller the copper thickness range, the better; the larger the TP value, the better; thermal shock reaches 3 times without hole copper fracture; ductility≧14%. The greater the ductility, the better the physical properties and the better the additive performance.

[0113] like Figure 3 As shown, the calculation method of the hole filling rate and the depression value is: hole filling rate = B / A*100%; hole filling depression value (Dimple) = AB.

[0114] like Figure 4 As shown, there are 6 types of hole filling defects:

[0115] like Figure 5 As shown, COV (uniformity) test method;

[0116] like Figure 6 As shown, TP (thickness plating capability) test method;

[0117] Thermal shock: Immerse the electroplated board in a lead-free tin furnace at 288°C for 10 seconds, take it out and place it in the air for 10 seconds, which is a thermal shock. Repeat this cycle 3-6 times. After at least 3 tests, make slices and check whether the copper layer is broken.

[0118] Ductility test for this test: Tested in accordance with IPC-TM-650.2.4.18.1.

[0119] like Figure 2 The figure is a SEM image of the copper plating liquid composition for filling holes of a blind hole plate embodiment with a hole depth of 75 μm and a hole diameter of 110 μm for copper plating. The electroplated copper thickness of the HDI board is 10.7 μm, the hole filling rate is greater than 95%, and the depression value is less than 3 μm.

[0120] It can be seen from the above test examples that the solution of the present invention, while ensuring the excellent physical properties of the via-filling copper plating, greatly improves the via-filling copper plating efficiency of the plating solution and enhances various performances, making the via-filling copper plating process of better quality, lower cost and greater reliability.

[0121] The above description is only an embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A HDI board hole-filling copper plating solution composition, comprising a hole-filling copper plating solution base liquid, a leveling agent, a brightener and a wetting agent, characterized in that: The leveling agent comprises 1-2% v / v polyether, 0.1-0.5% w / v polyethylene glycol 20000, 2-3% v / v leveling aid, 0.4-0.6% v / v sulfuric acid, 0.3-0.6% v / v formaldehyde, 0.2-0.3% w / v gallstone, and 93-96% v / v deionized water; The brightener comprises 1-2% v / v polyether, 0.1-0.5% w / v polyethylene glycol 20000, 0.1-0.5% v / v sodium polydisulfide dipropane sulfonate, 0.4-0.6% v / v sulfuric acid, 0.3-0.6% v / v formaldehyde, 0.2-0.3% w / v gallstone, and 95.5-97.9% v / v deionized water; The wetting agent comprises 12-20% v / v polyether, 2-5% w / v polyethylene glycol 20000, 0.4-0.6% v / v sulfuric acid, 0.4-0.6% v / v formaldehyde, 0.2-0.3% w / v gallstone, and 73.5-85% v / v deionized water; The preparation method of the leveling agent is: a. Add deionized water to the reactor, start stirring, slowly add sulfuric acid and stir evenly; b. Add polyether, polyethylene glycol 20000 and leveling agent to the reactor and stir until completely dissolved; c. Add formaldehyde to the reactor and stir evenly; d. Add gallstones to the reactor and stir until completely dissolved to obtain the leveling agent; The preparation method of the brightener is: a. Add deionized water to the reactor, start stirring, slowly add sulfuric acid and stir evenly; b. Sequentially add polyether, polyethylene glycol 20000, and sodium polydisulfide propane sulfonate to the reactor and stir until completely dissolved; c. Add formaldehyde to the reactor and stir evenly; d. Add gallstones to the reaction kettle and stir until completely dissolved and uniformly dissolved to obtain the brightener.

2. The HDI board hole filling copper plating solution composition according to claim 1, characterized in that: The preparation method of the wetting agent is: a. Add deionized water to the reactor, start stirring, slowly add sulfuric acid and stir evenly; b. Sequentially add polyether and polyethylene glycol 20000 to the reactor and stir until completely dissolved; c. Add formaldehyde to the reactor and stir evenly; d. Add gallstones to the reaction kettle and stir until completely dissolved and uniformly dissolved to obtain the brightener.

3. The HDI board hole filling copper plating solution composition according to claim 1, characterized in that: The base solution of the hole-filling copper plating solution includes 30-50 g / L of sulfuric acid, 200-250 g / L of copper sulfate and 30-70 ppm of chloride ions.

4. The HDI board hole-filling copper plating solution composition according to claim 3, characterized in that: The added amount of the leveling agent is 15-25 mL / L.

5. The HDI board hole-filling copper plating solution composition according to claim 4, characterized in that: The amount of the brightener added is 1-2 mL / L.

6. The HDI board hole-filling copper plating solution composition according to claim 5, characterized in that: The amount of the wetting agent added is 10-20 mL / L.

7. The HDI board hole-filling copper plating solution composition according to claim 1, characterized in that: The polyether is any one of propylene glycol block polyether, polyether F-6, polyether NPE-108, polyether NPE-105 and random polyether.

8. The HDI board hole-filling copper plating solution composition according to claim 1, characterized in that: The leveling aid is butynediol diethoxy ether.

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