KR100439534B1 - Leveler for electroplating - Google Patents

Abstract

The present invention relates to an electroplating composition for fine pattern or microhole plating, the plating composition according to the present invention comprises an alkane, cycloalkane or phenol sulfonic acid or derivative thereof having at least one or more fluorine substituents as a leveler (leveler) It is characterized in that, it is possible to provide a plating film excellent in uniformity in the fine pattern and the fine holes.

Description

Leveling agent for electroplating {LEVELER FOR ELECTROPLATING}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electroplating composition for plating micropatterns or microholes, and more particularly to a plating composition in which a specific sulfonic acid having a fluorine substituent or a derivative thereof is added as an additive to significantly improve the uniformity of the plating film.

The process of plating fine patterns and holes is a key process in the semiconductor and printed circuit board (PCB) industries. For example, in the case of semiconductors, many attempts have been made to use copper as metal wiring, and the core of this technology is uniform plating in fine holes and fine patterns. In addition, in the PCB industry, as the integration and fine patterning are made, the uniform plating of the fine holes and the fine patterns is emerging as a problem to be urgently solved.

Additives for electroplating compositions can be broadly divided into brighteners, levelers, and ion carriers. The leveling agent is an additive that serves to reduce the fine roughness of the surface of the plated film to help form the plated film uniformly during the plating process, for example, sulfuric acid including an alkane-based surfactant. The polisher is basically similar to the leveling agent, but serves to reduce the fine roughness to further polish the plating surface, for example, propane sulfuric acid having a surface active group. In addition, the carrier serves to reduce the surface tension of the plating liquid to facilitate the plating of the micropattern and the microholes, for example, a polyalkylene glycol-based polymer.

In the case of using the conventionally developed sulfonic acid-based additive, there is still a need to develop a plating composition that satisfies uniformity and productivity simultaneously due to the lack of uniformity of the plating film. In addition, improvements in electrical and mechanical plating equipment have been made to improve the plating property, but this also has not been effective in terms of initial investment cost and productivity.

Accordingly, the present invention aims to develop an additive having an effect of forming a uniform plating film while maintaining high productivity in microhole and micropattern plating.

1 is a photograph showing a cross section of a plating film in the case of plating a fine hole using a copper electroplating composition according to the prior art,

FIG. 2 is a photograph showing a cross section of a plating film in the case where the micro holes are plated using the copper electroplating composition including a specific leveling agent according to the present invention.

In accordance with the above object, the present invention provides a leveler for electroplating comprising a sulfonic acid compound containing at least one fluorine substituent.

Hereinafter, the present invention will be described in more detail.

The electroplating composition of the present invention can be applied to the plating of all metals (eg, copper, tin, nickel, zinc, gold, silver, cobalt, etc.) used in the semiconductor or PCB field, the metal source used in the plating composition May be any water soluble metal source commonly used as the source of the metal in question.

The sulfonic acid derivative used as an additive in the present invention is characterized in that it has a fluorine radical, a fluorine substituted alkane sulfonic acid or a derivative thereof of the formula (1), a fluorine substituted cycloalkane sulfonic acid or a derivative thereof of the formula (2) or It may be represented by a fluorine substituted phenol sulfonic acid or a derivative thereof of formula 3:

Where

R ¹ to R ⁷ are each independently fluorine (F), hydrogen (H), C _p H _{2p + 1} or C _p F _{2p + 1} wherein p is 1 to 4, wherein at least one of R ¹ to R ⁵ And at least one of R ⁶ and R ⁷ is fluorine (F),

A is an alkali metal, alkaline earth metal, hydrogen, —NB ¹ B ² B ³ B ⁴ , wherein B ¹ to B ⁴ are each independently hydrogen or alkyl, aryl or aralkyl,

n is a number ranging from 0 to 18.

In the above formula, it is preferable that both R ¹ to R ⁵ are fluorine, both R ⁶ and R ⁷ are fluorine, and A is an alkali metal.

The use concentration of the additive according to the present invention may range from 1 to 3,000 mg / L in the plating composition.

The plating composition of the present invention may further contain other additives commonly used in the plating composition in an amount within a range that does not impair the effects of the present invention.

The plated film of the desired metal may be electroplated on the substrate by immersing the substrate to be plated in the plating composition of the present invention as a cathode and applying an appropriate current at room temperature for an appropriate time using a plating metal as the anode.

By using the plating composition of the present invention, it is possible to obtain a plated film having excellent uniformity even in fine holes or fine patterns.

The present invention is described below by way of examples, which do not limit the invention.

Example

On a general substrate for PCB, where a thin copper film is formed to a thickness of 20 μm on the entire surface of a glossy epoxy resin substrate, about 150 μm holes are formed to a depth of about 60 to 70 μm, and chemical copper can be used for electroplating. And an organic copper plated PCB substrate (10 cm × 1 cm) was prepared.

To prepare a water-based plating compositions having a composition as shown in Table 1, to the 300 mL of the plating composition to connect the PCB substrate as a cathode, the plating copper plate (P content 3 to 5% by weight) as an anode temperature 25 ℃, The plating was performed for 60 minutes under the condition of 20 mA / cm ² current.

Example 1 Comparative Example 1 Copper Sulfate (CuSO ₄ -5H ₂ O) 75 g / L Copper Sulfate (CuSO ₄ -5H ₂ O) 75 g / L Concentrated sulfuric acid (H ₂ SO ₄ , about 95% by weight) 190 g / L Concentrated sulfuric acid (H ₂ SO ₄ , about 95% by weight) 190 g / L Hydrochloric acid (HCl, 35 wt%) 12 ml / L Hydrochloric acid (HCl, 35 wt%) 12 ml / L Shipley CG125-A 5 ml / L Shipley's CG125-A 5 ml / L Shipley's CG125-B 20 ml / L Shipley's CG125-B 20 ml / L Potassium nonafluorobutane sulfonate 667 mg / L -

In order to compare the plating uniformity of the obtained plating film, the cross section of the microhole part of the board | substrate was observed in the plating film obtained from the composition of Example 1 and the comparative example 1, and the result is shown to FIG. 1 and FIG. 2, respectively.

By comparing FIG. 1 and FIG. 2, it can be seen that the inside of the microholes is more uniformly plated when using the additive according to the present invention.

According to the present invention, a metal electroplating composition comprising a fluorine substituent-containing specific sulfonic acid or a derivative thereof as an additive may plate the micro holes and the micro patterns more uniformly.

Claims (5)

A leveling agent for electroplating comprising a sulfonic acid compound containing at least one fluorine substituent. The method of claim 1, An electroplating leveling agent, characterized in that it is an alkane sulfonic acid type of Formula 1, a cycloalkane sulfonic acid type of Formula 2, or a phenol sulfonic acid type compound of Formula 3 or a derivative thereof having a fluorine substituent: Formula 1 Formula 2 Formula 3 Where R ¹ to R ⁷ are each independently fluorine (F), hydrogen (H), C _p H _{2p + 1} or C _p F _{2p + 1} wherein p is 1 to 4, wherein at least one of R ¹ to R ⁵ And at least one of R ⁶ and R ⁷ is fluorine (F), A is an alkali metal, alkaline earth metal, hydrogen, —NB ¹ B ² B ³ B ⁴ , wherein B ¹ to B ⁴ are each independently hydrogen or alkyl, aryl or aralkyl, n is a number ranging from 0 to 18. The method of claim 2, In the formula, R ¹ to R ⁷ are all fluorine, A is an alkali metal, leveling agent for electroplating. delete The method of claim 1, An electroplating leveling agent, characterized by being used for copper, tin, nickel, zinc, gold, silver or cobalt plating.