IC (integrated circuit) carrier plate film removing agent and preparation and use methods thereof

Abstract

The invention discloses an IC (integrated circuit) carrier plate film removing agent as well as a preparation method and a use method thereof. The copper plating solution comprises the following components in percentage by mass: 1-3% of an amino acid imidazole copper protective agent, 10-15% of ammonia alcohol organic alkali, 2-9% of a compound surfactant and the balance of water, the compound surfactant is a composition of a terphenyl derivative wetting agent and an alcohol ether surfactant. All the components in the film stripping agent are coordinated, a film material on a high-precision circuit IC carrier plate can be efficiently removed, and the minimum line width / line distance capable of effectively stripping a film can reach 6 / 6 [mu] m; meanwhile, dry film cracking fragments are small, residues or film clamping phenomena are avoided, the copper surface is not corroded, and blackening of equipment rollers and groove bodies is avoided.

Description

Technical Field

[0001] The invention relates to the technical field of IC carrier board film removal technology, and in particular to an IC carrier board film stripping agent and a preparation and use method thereof. Background Art

[0002] IC substrate, also known as package substrate, is developed on the basis of HDI circuit board. It is a technological innovation that adapts to the rapid development of electronic packaging technology. It has excellent characteristics such as high density, high precision, high performance, miniaturization and thinness. It is mainly used to establish signal connection between IC and PCB. In addition, it can also protect circuits, fix routes and dissipate excess heat. Compared with conventional PCB boards, IC substrates have smaller line widths and line spacings, and smaller board sizes. Usually, line widths / line spacings of 50 / 50μm belong to high-end PCB products, while in the field of IC substrate manufacturing, line widths / line spacings within 30 / 30μm belong to conventional products.

[0003] IC substrates can be divided into hard substrates, flexible substrates and ceramic substrates. Hard substrates can be further divided into BT, ABF, and MIS substrates. Compared with BT resin, ABF substrates have the advantage of finer lines, which are suitable for ICs with high pin counts and high transmission. They are mainly used for high-performance computing (HPC) chip packaging such as CPU, GPU, and FPGA. With the rise of new technologies and applications such as AI, 5G, and autonomous driving, the huge chip opportunities hidden behind them have greatly promoted the market growth of ABF substrates in IC substrates. As a result, companies' requirements for ABF substrates have gradually increased, mainly reflected in: 1) Larger area (currently developing to more than 110mm*110mm); 2) Finer line width / line spacing (developing to less than 5 / 5μm).

[0004] In the process of making IC substrates, dry film needs to be removed after being applied to circuit pattern transfer. Traditional stripping solutions mostly use inorganic alkali solutions of a certain concentration of NaOH or KOH, or organic alkali solutions as stripping agents to peel off the dry film. However, since IC substrates, especially ABF substrates, have finer line widths / line spacings, higher requirements are placed on the bonding strength between the dry film and the copper surface, which increases the difficulty of subsequent dry film stripping. When the above-mentioned traditional stripping agents are used to strip IC substrates, problems such as incomplete film stripping, sandwiched buns or copper surfaces, and blackening and damage to the tank body or equipment rollers are likely to occur. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides an IC substrate stripping agent and a preparation and use method thereof.

[0006] The technical solution of the present invention is:

[0007] An IC substrate stripping agent, characterized in that it comprises the following components by mass fraction: 1-3% amino acid imidazole copper protective agent, 10-15% amino alcohol organic base, 2-9% compound surfactant and balance water; the compound surfactant is a combination of terphenyl derivative wetting agent and alcohol ether surfactant.

[0008] Furthermore, the amino acid imidazole copper protective agent includes at least one of 3-imidazolyl-L-alanine, D-2-amino-3-(4-imidazolyl) propionic acid, and 3-methyl-L-histidine.

[0009] Imidazole compounds are the most widely used organic protective agents for copper. Imidazole compounds have good coordination reaction activity with metallic copper and can be instantly adsorbed on the copper surface to produce dense anti-oxidation and anti-corrosion films. Compared with the common imidazole compound benzimidazole (BTA) or its derivative methylbenzimidazole (TTA) in the prior art, the amino acid imidazole copper protective agent of the present invention is the same as the imidazole ring in BTA or TTA, which forms a coordination bond with copper and is adsorbed on the copper surface to form an anti-corrosion film; the difference is that the amino acid imidazole of the present invention contains an amino group, and the H in the amino group can generate hydrogen bonds with electronegative atoms in acid-based resin dry film materials, such as oxygen in the carboxyl group. When the amino group forms hydrogen bonds with the dry film material, these hydrogen bonds will be inserted into the molecules of the dry film material, destroying the original intermolecular interactions, thereby weakening the overall structure of the dry film, making it more flexible, and ultimately making the dry film material more prone to deformation and rupture when subjected to external forces; in addition, when the hydrogen bonds are inserted between the dry film and the layout, the interaction between the two is weakened, thereby reducing the adhesion of the dry film and making it easier to fall off.

[0010] Furthermore, the amino alcohol organic base includes at least one of 3-hydroxy-N,N-diethylaniline, 1-(4-hydroxyphenyl)-2-(methylamino)ethanol, 1-(4-hydroxyphenyl)-2-aminoethanol, and 1-(3,4-dihydroxyphenyl)-2-(methylamino)ethanol.

[0011] The amino alcohol organic base of the present invention has both phenolic hydroxyl and amino functional groups, which makes it have higher reactivity and selectivity in chemical reactions, making it faster in film stripping rate, and more accurately reacting to specific dry film layer materials without affecting other parts of the circuit board, which helps to reduce the damage to the circuit on the carrier board during the film stripping process and improves the quality of the finished product. In addition, the amino alcohol organic base of the present invention produces fewer by-products during the film stripping process, which is easier to process or recycle, reduces the pollution of the film stripping process to the environment, and is more in line with the requirements of modern industry for environmental protection. At the same time, the amino alcohol organic base of the present invention is suitable for a variety of different types of film materials, photoresists, etc.

[0012] Furthermore, the alcohol ether surfactant includes at least one of 2-hydroxy-4-methylanisole, α-[3,5-dimethyl-1-(2-methylpropyl)hexyl]-ω-hydroxypoly(oxy-1,2-ethanediyl), hydroquinone monohexyl ether, and p-hydroxyphenyl ethyl ether.

[0013] Furthermore, the terphenyl derivative wetting agent includes at least one of 4,5-diphenyl-1,3-phthalic acid and 1-(2,6,2",6"-tetramethyl-(1,1',3',1")terphenyl-2'-yl)-ethanol.

[0014] The terphenyl derivative wetting agent includes three conjugated benzene rings, which form an extended large conjugated system in structure. It has good thermal stability, making it more resistant to decomposition in the high-temperature environment of film stripping, avoiding failure due to high temperature, thereby ensuring stability and reliability in the film stripping process. It is used in combination with alcohol ether surfactants. On the one hand, it significantly reduces the surface tension of the dry film, making it easier for the amino alcohol organic base in the film stripping agent system to act on the dry film and crack the dry film. In addition, the π electrons in the multiple conjugated benzene ring structures in the terphenyl derivative wetting agent can interact with other molecules, thereby increasing its solubility in the film stripping agent system solution, so that the dry film is cracked more finely, avoiding the generation of large dry film fragments and the occurrence of film sandwiching.

[0015] Furthermore, the mass ratio of the alcohol ether surfactant to the terphenyl derivative wetting agent is 1:(2-4).

[0016] Furthermore, the mass ratio of the amino acid imidazole copper protective agent, the amino alcohol organic base and the compound surfactant is 1:(5-10):(2-3).

[0017] The present invention also provides a method for preparing the IC substrate stripping agent, which comprises the following steps: adding amino acid imidazole copper protective agent, amino alcohol organic base, alcohol ether surfactant, and terphenyl derivative wetting agent into water in proportion, stirring until completely dissolved, and obtaining the IC substrate stripping agent.

[0018] The method for using the IC substrate stripping agent includes a stripping agent temperature of 40-50°C, a moving line speed of 1.5-2.0 m / min, and a spray pressure of 2.0-3.0 kg / cm 2 .

[0019] The present invention adopts a spraying method to spray from the top and bottom of the board surface to the middle, so that the dry film is accelerated to separate from the board surface, so as to achieve effective auxiliary film removal.

[0020] The beneficial technical effect of the present invention is: the present invention comprises an amino acid imidazole copper protective agent, an amino alcohol organic base, a compound surfactant and a residual amount of water, the compound surfactant is a composition of a terphenyl derivative wetting agent and an alcohol ether surfactant, and the components work in coordination to efficiently remove the dry film on the high-precision circuit IC carrier, and the minimum line width / line spacing for effective film removal reaches 6 / 6μm; at the same time, the dry film cracking fragments are small, there is no residue or film clamping phenomenon, and it does not corrode the copper surface, and will not cause the blackening of the equipment roller and the trough body. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is an appearance diagram of a third IC carrier board of the present invention;

[0022] Figure 2 This is a diagram showing the appearance of the dry film on the third IC carrier board in Example 6 of the present invention after being cracked by the film stripping agent;

[0023] Figure 3 This is a microscopic magnified image of the 6 / 6 μm line width / line spacing of the third IC carrier after being treated with the stripper of Example 6 of the present invention;

[0024] Figure 4 This is a diagram showing the appearance of the dry film on the third IC carrier board in Example 7 of the present invention after being cracked by the film stripping agent;

[0025] Figure 5 This is a picture showing the appearance of the dry film on the second IC carrier in Comparative Example 1 of the present invention after being cracked by the film stripping agent;

[0026] Figure 6 This is a picture showing the appearance of the dry film on the third IC carrier in Comparative Example 4 of the present invention after being cracked by the film stripping agent;

[0027] Figure 7 This is a microscopic magnified image of the 6 / 6 μm line width / line spacing of the third IC carrier after being treated with the stripping agent of Comparative Example 4 of the present invention;

[0028] Figure 8 This is a picture showing the appearance of the dry film on the third IC carrier in Comparative Example 10 of the present invention after being cracked by the film stripping agent;

[0029] Fig. 9 This is a microscopic magnified image of the 6 / 6 μm line width / line spacing of the third IC carrier after being treated with the stripper of Comparative Example 10 of the present invention. DETAILED DESCRIPTION

[0030] In order to be able to more clearly understand the technical means of the present invention and to implement it according to the contents of the specification, the specific embodiments of the present invention are further described in detail below in conjunction with the drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention. The experimental reagents and instruments involved in the implementation of the present invention are all commonly used ordinary reagents and instruments unless otherwise specified.

[0031] The present invention provides an IC substrate stripping agent, which comprises the following components by mass percentage: 1-3% amino acid imidazole copper protective agent, 10-15% amino alcohol organic base, 2-9% compound surfactant and balance water; the compound surfactant is a composition of alcohol ether surfactant and terphenyl derivative wetting agent, wherein the mass ratio of the alcohol ether surfactant to the terphenyl derivative wetting agent is 1:(2-4). The mass ratio of the amino acid imidazole copper protective agent, the amino alcohol organic base and the compound surfactant is 1:(5-10):(2-3).

[0032] Amino acid imidazole copper protective agent, amino alcohol organic base, alcohol ether surfactant, terphenyl derivative wetting agent are added to water in proportion, stirred at room temperature (25°C) for 30 minutes, and allowed to stand to obtain the IC substrate stripping agent, which is used to remove the dry film on the IC substrate, so that the dry film is cracked into small particles or uniform small fragments to achieve stripping, and is also suitable for ordinary PCB circuit boards.

[0033] Table 1 shows the components and their contents (mass percentage %) in the IC substrate stripping agent of Examples 1-7.

[0034] Table 1

[0035]

[0036]

[0037] Table 2 shows the components and their contents (mass percentage %) in the stripping agents of Comparative Examples 1-10.

[0038] Table 2

[0039]

[0040]

[0041]

[0042] The IC substrate stripping agents of Examples 1-7 and the stripping agents of Comparative Examples 1-10 were subjected to stripping tests.

[0043] Stripping test includes:

[0044] S1, make a sample:

[0045] The present invention is provided with three kinds of IC carriers, which are ABF boards, and their length, width and thickness are all the same, which are 50cm*50cm*1μm. The dry film (acid-based resin) on the four IC carriers has the same thickness, which is 20μm, but the line width / line spacing thereon is different. They are all manufactured in sequence using the mSAP process.

[0046] The line width / line spacing on the first IC substrate is 15 / 15 μm; the line width / line spacing on the second IC substrate is 9 / 9 μm; the line width / line spacing on the third IC substrate is 6 / 6 μm, wherein, Figure 1 This is the appearance of the third IC carrier board. Figure 1 A is a circuit module, which is about 2mm*4mm in size and has about 200 circuits arranged on it.

[0047] S2, film stripping process:

[0048] The stripping agent is sprayed on the IC substrate to be stripped in a spraying manner. The spraying direction is to spray the board surface synchronously from top to bottom, so that the film is accelerated to separate from the surface and effectively assist in stripping. The upper spraying pressure and the lower spraying pressure are both 2.0kg / cm 2 The temperature of the stripping agent is 40°C, and the moving line speed of the IC substrate to be stripped is 1.5m / min.

[0049] The film stripping effects of Examples 1-7 and Comparative Examples 1-10 on the first IC substrate are shown in Table 3.

[0050] Table 3

[0051]

[0052]

[0053] The film stripping effects of Examples 1-7 and Comparative Examples 1-10 on the second IC substrate are shown in Table 4.

[0054] Table 4

[0055]

[0056]

[0057] The film stripping effects of Examples 1-7 and Comparative Examples 1-10 on the third IC substrate are shown in Table 5.

[0058] Table 5

[0059]

[0060]

[0061] By analyzing the test results of the embodiments and comparative examples in Tables 3, 4 and 5, it can be seen that within the set range, the film stripping agent of the present invention has excellent film stripping ability for the dry film on the first IC substrate, the second IC substrate and the third IC substrate, corrosion inhibition of the substrate surface, the tank body and the roller, and film prevention ability. In addition, as shown in the test results of Examples 1-2 and 5-6 in Tables 3-5, when the mass ratio of the amino acid imidazole copper protective agent, the amino alcohol organic base and the surfactant is 1: (5-10): (2-3), while ensuring clean film stripping without corrosion and film sandwiching, the appearance of the removed dry film is uniform small particle fragments, that is, it has a stronger cracking ability for the dry film. Among them, when Example 6 acts on the third IC substrate, its film fragmentation is as follows: Figure 2 As shown, it is in the form of uniform small particles and fragments. The enlarged picture of the third IC carrier after stripping is as follows Figure 3 When Example 7 acts on the third IC substrate, the film is broken as shown in FIG. Figure 4 As shown, it is in the form of uniform small fragments.

[0062] Since the ratio of each component in the stripper system of Comparative Examples 1-10 is not within the range set by the present invention, the stripping effect on the first IC substrate and the second IC substrate is relatively poor, which is mainly manifested in different degrees of film clamping, different degrees of dry film cracking, large and long fragments, blackening of the board surface or blackening of the tank body and the roller, and increased stripping time; further, since the third IC substrate has a narrower line spacing / line width than the first and second IC substrates, its line width / line spacing is only 6 / 6μm, when Comparative Examples 1-10 are applied to the third When the IC carrier is used, it is accompanied by a more serious film clamping phenomenon. This is mainly because during the film stripping process, the expanded dry film is firmly clamped between the narrower circuits. On the one hand, the film stripping agent of comparative examples 1-10 has insufficient wetting ability for the narrower circuits, and on the other hand, its degree of cracking of the dry film is limited, which ultimately leads to the problem that the film clamping phenomenon becomes more serious as the line width / line spacing of the carrier decreases. It even causes comparative examples 1-10 to fail to complete the film stripping action within 180s when acting on the third IC carrier, that is, there are some areas on the board where the dry film is not removed. Needless to say, the film clamping phenomenon directly affects the performance of the IC carrier. In addition to indirectly causing the film clamping problem, the different degrees of cracking of the dry film are also prone to cause the problem of the dry film section being too long and winding around the equipment roller.

[0063] Specifically, in Comparative Examples 1 and 5, there is no amino acid imidazole copper protective agent in the stripper or the content of the amino acid imidazole copper protective agent is too low. On the one hand, it directly leads to the copper surface of the IC substrate not producing a dense anti-oxidation and anti-corrosion film, and the copper surface of the first IC substrate to the third IC substrate is blackened or partially blackened; on the other hand, the stripper system lacks the synergistic softening effect of the amino acid imidazole copper protective agent on the dry film, resulting in uneven fragmentation of the dry film. When Comparative Example 1 acts on the first and second IC substrates, the appearance of the removed dry film is uneven fragments or has the following characteristics: Figure 5 Furthermore, when it acts on the third IC substrate, because the third IC substrate has a narrower line spacing / line width than the first and second IC substrates, the appearance of the withdrawn dry film appears as a whole film scrap.

[0064] Comparative Example 2 does not contain an amino alcohol organic base, which results in not only incomplete film stripping and serious film sandwiching, but also the problem of film scraps, which easily causes the problem of the dry film section being too long and winding around the equipment roller. As shown in Comparative Example 6, it contains too much amino alcohol organic base, which, on the one hand, easily causes the board surface, the tank body and the roller to turn black, and on the other hand, because the ratio of the amino alcohol organic base to the compound surfactant is not within the preset range of this aspect, the film stripping agent system has poor ability to crack the dry film.

[0065] In the systems of Comparative Examples 3 and 4, there is only a single alcohol ether surfactant or a terphenyl derivative wetting agent in the compound surfactant, or as shown in Comparative Examples 7-8, the alcohol ether surfactant and the terphenyl derivative wetting agent in the compound surfactant system are not in the ratio within the set range. Therefore, firstly, the surface tension of the system is higher, and secondly, the solubility of the compound surfactant in the stripping agent system is reduced, which ultimately affects the stripping and film cracking effects. When Comparative Example 4 acts on the first and second IC substrates, the appearance of the stripped dry film is uneven fragments. When Comparative Example 4 acts on the third IC substrate, the appearance of the stripped dry film is Figure 6 The third IC carrier board is shown as a whole film scrap. The enlarged picture of the carrier board after the film stripping agent of comparative example 4 is shown as follows: Figure 7 shown.

[0066] Comparative Example 9 tried different organic bases. When the organic bases were applied to the first IC substrate, the substrate surface did not turn black, but the tank and roller turned black. When the organic bases were applied to the second and third IC substrates, the substrate surface, tank and roller turned black. This is also a common problem in the prior art. When facing a wider line width / line spacing, a certain proportion of organic base combined with a copper protective agent can prevent the substrate surface from turning black. However, as the line width / line spacing further narrows, due to the limited surface tension of the stripping agent system and the synergistic effect between the components, Its ability to strip the IC substrates with narrower and smaller line widths / line spacings is also significantly weakened, which can easily lead to the problem of blackening of the IC substrate surface with narrower and smaller line widths / line spacings. In addition, although a certain proportion of copper protective agent mixed with an organic base can avoid the blackening of the IC substrate surface with wider line widths / line spacings, the alkalinity of the organic base in the prior art is relatively high, and the copper protective agent cannot form a protective film on the trough body and roller as instantly as on the substrate surface. Therefore, the stripping agent system cannot avoid the blackening of the trough body and roller, thereby affecting the effective use of the production equipment.

[0067] Similarly, in Example 10, different organic bases and copper protective agents were tried. In addition to the blackening of the board surface, tank body and roller, the more obvious problem was the poor cracking ability of the dry film, especially when facing the second and third IC carriers, accompanied by a more serious film clamping phenomenon. When it acted on the third IC carrier, the appearance of the dry film removed was as follows: Figure 8 The third IC carrier board is shown as a whole film scrap. The enlarged picture of the carrier board after the film stripping agent of comparative example 10 is shown as follows: Fig. 9 shown.

[0068] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the technical principles of the present invention, and these improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. An IC substrate stripping agent, characterized in that: The invention comprises the following components by mass fraction: 1-3% amino acid imidazole copper protective agent, 10-15% amino alcohol organic base, 2-9% compound surfactant and balance water; the compound surfactant is a composition of terphenyl derivative wetting agent and alcohol ether surfactant.

2. The IC substrate stripping agent according to claim 1, characterized in that: The amino acid imidazole copper protective agent includes at least one of 3-imidazolyl-L-alanine, D-2-amino-3-(4-imidazolyl) propionic acid and 3-methyl-L-histidine.

3. The IC substrate stripping agent according to claim 1, characterized in that: The amino alcohol organic base includes at least one of 3-hydroxy-N,N-diethylaniline, 1-(4-hydroxyphenyl)-2-(methylamino)ethanol, 1-(4-hydroxyphenyl)-2-aminoethanol, and 1-(3,4-dihydroxyphenyl)-2-(methylamino)ethanol.

4. The IC substrate stripping agent according to claim 1, characterized in that: The alcohol ether surfactant includes at least one of 2-hydroxy-4-methylanisole, α-[3,5-dimethyl-1-(2-methylpropyl)hexyl]-ω-hydroxypoly(oxy-1,2-ethanediyl), hydroquinone monohexyl ether, and p-hydroxyphenyl ethyl ether.

5. The IC substrate stripping agent according to claim 1, characterized in that: The terphenyl derivative wetting agent includes at least one of 4,5-diphenyl-1,3-phthalic acid and 1-(2,6,2",6"-tetramethyl-(1,1',3',1")terphenyl-2'-yl)-ethanol.

6. The IC substrate stripping agent according to claim 1, characterized in that: The mass ratio of the alcohol ether surfactant to the terphenyl derivative wetting agent is 1:(2-4).

7. The IC substrate stripping agent according to claim 1, characterized in that: The mass ratio of the amino acid imidazole copper protective agent, the amino alcohol organic base and the compound surfactant is 1:(5-10):(2-3).

8. A method for preparing an IC substrate stripping agent according to any one of claims 1 to 7, characterized in that: The method comprises the following steps: adding amino acid imidazole copper protective agent, amino alcohol organic base, alcohol ether surfactant and terphenyl derivative wetting agent into water in proportion, stirring until completely dissolved, and obtaining IC substrate stripping agent.

9. A method for using the IC substrate stripping agent according to any one of claims 1 to 7, characterized in that: Including stripping agent temperature 40-50℃, moving line speed 1.5-2.0m / min, spray pressure 2.0-3.0kg / cm 2 .

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