KR101250768B1 - Method for removing photoresist by using electrolytic degrease - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of peeling photoresist using electrolytic degreasing to improve peelability, wherein the photoresist is coated on a conductive or insulating material, followed by a photoresist coating, exposure and development process. In the method of peeling the photoresist by means, the peeling means is provided by a current application method using electrolytic degreasing, to provide a photoresist stripping method, photodedicated, in particular electrodeposited photoresist It is economical by not using a stripping solution, and the length and time of the stripping process can be shortened to provide a photoresist stripping method using an electrolytic degreasing having high peeling efficiency and excellent stripping effect.

Description

Photoresist stripping method using electrolytic degreasing {METHOD FOR REMOVING PHOTORESIST BY USING ELECTROLYTIC DEGREASE}

The present invention relates to a method of peeling a photoresist, and more particularly, to a method of peeling a photoresist using electrolytic degreasing to improve peelability.

In general, a substrate for mounting an electric device including an IC chip has a photoresist patterning step of coating, exposing and developing an inorganic substrate with photoresist, and forming a fine circuit through an etching and plating process. And peeling the patterned photoresist film. In this case, the photoresist is a composition having good adhesion and chemical resistance with a metal foil capable of sufficiently protecting the lower metal layer portion from various solvents used for development, etching, and the like, and is generally referred to as a dry film photoresist; DFR ') is then used to remove the photoresist in a dipping or spray manner using various strippers to remove the photoresist layer.

For example, in the case of a lead frame for an IC chip mounting substrate, a fine pitch, more I / O contact points, and lighter and shorter weights to make the spacing between internal leads more compact are taken as an example. Electrodeposition photoresist is used in place of the DFR for improvement. Electrodeposited photoresist can implement a photoresist layer with a fine pattern and three-dimensional, it can be said that the application value is higher than the existing DFR.

On the other hand, in the peeling process in the case of coating such electrodeposition photoresist, the peeling liquid is used similarly to the case of coating the conventional DFR. However, as the exfoliation of the electrodeposited photoresist, a separate exfoliation solution is used, and as such exfoliation solution, a exfoliation solution (trade name: REMOVER R-110) of Honey Chemicals Co., Ltd., Japan. .

Such electrodeposited photoresist stripper is expensive, and in order to achieve perfect stripping, it is necessary to use a dedicated stripper provided by the manufacturer of the electrodeposited photoresist solution. In addition, in order to improve the peeling ability by using the dedicated peeling liquid, it is necessary to proceed with the peeling process under the process conditions proposed by the dedicated equipment and the dedicated peeling liquid manufacturer. For example, there are general conditions such as spray pressure improvement, stripping process time extension, stripping stock solution concentration, and the like. The peeling process is composed of a total of four stages so that the total length of the peeling line is about 3m, the peeling line and the peeling time may be longer depending on the exposure and plating conditions. Therefore, if the conditions proposed by the electrodeposition photoresist solution manufacturers and equipment providers are applied as they are, there is a problem in that the manufacturing cost increases further due to the lengthy line length and the long time for the peeling together with the expensive dedicated stripper burden.

Therefore, the present invention has been made to solve the above problems, in the photoresist stripping method including the electrodeposition photoresist, it is economical and excellent in the peeling effect by performing a current application method using electrolytic degreasing without using a dedicated stripping solution A photoresist stripping method is proposed.

According to an aspect of the present invention,

(1) A method of peeling the photoresist using a peeling means after a photoresist coating, exposure and development process on a conductive or insulating material, wherein the peeling means is performed by a current application method using electrolytic degreasing. The current has a current density of 20 to 100 A / dm 2, and the electrolytic degreasing is 30 to 60 wt% of sodium hydroxide (NaOH) or potassium hydroxide (KOH), 0.001 to 10 wt% of a surfactant, and 30 to 60 wt% of an erosion inhibitor. It provides a peeling method of a photoresist, characterized by using an electrolytic degreasing agent containing%.

(2) The photoresist peeling method according to (1), wherein the photoresist is an electrodeposition photoresist.

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Moreover, in order to solve the said subject,

(8) comprising 30 to 60% by weight of sodium hydroxide (NaOH) or potassium hydroxide (KOH), 0.001 to 10% by weight of surfactant and 30 to 60% by weight of erosion inhibitor, and photoresist coating, exposure and Provided is an electrolytic degreasing agent for photoresist stripping used to peel the photoresist after a developing process.

(9) The electrolytic degreasing agent for photoresist stripping according to (8), wherein the photoresist is an electrodeposition photoresist.

Such a photoresist stripping method according to the present invention is economical (about 1/7 of the price of a dedicated stripping solution in the case of electrodeposited photoresist) without using a photoresist stripping solution, and the stripping process length and time are shortened and It is possible to provide a photoresist stripping method using electrolytic degreasing with high peeling efficiency and excellent peeling effect.

1 is a schematic diagram illustrating the peeling action of sodium hydroxide as an electrolytic degreasing agent component according to an embodiment of the present invention;
2 is a schematic diagram illustrating the peeling action of sodium hydroxide and a surfactant as an electrolytic degreasing agent component according to an embodiment of the present invention;
3 is a cross-sectional view showing a part of a substrate manufacturing process for mounting an electric device using the electrodeposition photoresist stripping method for etching according to an embodiment of the present invention;
4 and 5 are cross-sectional views showing a process for manufacturing a substrate for mounting an electric device using the electrodeposition photoresist stripping method for plating according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The terms or words used in this specification and claims are not to be construed as limiting in their usual or dictionary meanings, and the inventors may properly define the concept of terms in order to best explain their invention in the best way possible. It should be interpreted as meaning and concept corresponding to the technical idea of the present invention. Therefore, the embodiments described in this specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention and do not represent all the technical ideas of the present invention. Therefore, It is to be understood that equivalents and modifications are possible. Here, like reference numerals in the drawings denote like elements.

The present invention relates to a method of peeling the photoresist using a peeling means after a photoresist coating, exposure and development process on a conductive or insulating material, wherein the peeling means is performed by a current application method using electrolytic degreasing. It is characterized by.

The electrolytic degreasing is used to remove the rust-preventing treatment and other organic substances in the pretreatment process of the conductive or insulating material, but the inventors of the present invention are economical in the case of using the electrolytic degreasing in the photoresist, in particular, the electrodeposition photoresist stripping process. It discovered that the peeling effect was excellent and led to this invention.

Performing the peeling process by the current application method using the electrolytic degreasing is an alternative to performing the peeling process using a conventional photoresist-only peeling liquid. In the case of using a conventional peeling liquid, a dipping or spray method is used, but the current application method using the electrolytic degreasing according to the present invention is performed by applying a current using an electrolytic degreasing to perform peeling. It focuses on the electrolytic principle used in a plating process, and is used for the photoresist peeling process. In addition to electroplating, electrolytic degreasing is used to remove rust and other organic substances on the surface of substrates, but electrolytic degreasing has not been used in photoresist, in particular electrodeposition photoresist stripping, as in the present invention. .

When current is applied (not shown) using electrolytic degreasing, the electrodeposition photoresist layer is separated from the surface of the conductive or insulating material by the electrical resistance between the photoresist layer and the conductive or insulating material. At this time, the electrolytic degreasing agent used for the electrolytic degreasing generally includes sodium hydroxide or potassium hydroxide, a surfactant, a corrosion inhibitor and an erosion inhibitor. Hereinafter, the case where the electrodeposition photoresist is coated will be described as an example.

1 is a schematic diagram illustrating the peeling action of sodium hydroxide as an electrolytic degreasing agent component according to an embodiment of the present invention, Figure 2 illustrates the peeling action of sodium hydroxide and a surfactant as an electrolytic degreasing agent component according to an embodiment of the present invention It is a schematic diagram.

Referring to FIG. 1, the electrodeposition photoresist 121 ′ is cured between the conductive materials 110 as an example. Sodium hydroxide serves to swell the photoresist 121 ′ to form and diffuse (a) a swirlen gel region 140. Subsequently, the swirlene gel 140 is salted by sodium cations (Na ⁺ ), dissolved (b), and peeled off (c) from the surface of the conductive material.

Referring to FIG. 2, as an embodiment, the electrodeposition photoresist 121 ′ cured between the conductive materials 110 is used as the sodium hydroxide and the surfactant as the electrolytic degreasing agent. In this case, the swelling action by sodium hydroxide is further activated by the surfactant to promote the formation and diffusion rate of the swirlen gel region 140 (a). Thereafter, after the chloride and dissolution (b) by the sodium cation, it is exfoliated (c). In other words, the surfactant serves to accelerate the swelling so that the peeling of the photoresist is better. As the surfactant, anionic surfactants, cationic surfactants, and nonionic surfactants can be used. However, it is preferable to use nonionic surfactants having excellent wettability and low bubble generation.

Here, the sodium hydroxide (or potassium hydroxide) is preferably included 30 to 60% by weight, more preferably 40 to 50% by weight based on the total weight of the electrolytic degreasing agent. When the sodium hydroxide content is less than 30% by weight, the swelling action by sodium hydroxide is not sufficient, and when the sodium hydroxide content is more than 60% by weight, damage to metallic materials such as patterns is not preferable.

In addition, the surfactant is preferably included from 0.001 to 10% by weight, more preferably from 0.01 to 1% by weight based on the total weight of the electrolytic degreasing agent. When the surfactant content is less than 0.001% by weight, the peeling effect on the surface of the substrate is not uniform, the penetration effect on the interface is insufficient, and the degree of acceleration of the swelling effect is insufficient, and when it exceeds 10% by weight, the peeling uniformity is This does not increase, but rather a large amount of bubbles are generated, there is a problem in the process handling.

In addition to the sodium hydroxide or potassium hydroxide and a surfactant, an erosion inhibitor for preventing erosion of the plating pattern during electrolytic degreasing is included. In the case of the electrolytic degreasing agent according to the present invention, the erosion inhibitor is 30 to 60 weight based on the total weight of the electrolytic degreasing agent. % May be included.

At this time, the concentration of the electrolytic degreasing agent used for the electrolytic degreasing is preferably 40 ~ 200g / ℓ. When the said concentration is less than 40 g / L, peeling effect is inadequate and it is not good. When it exceeds 200 g / L, peeling effect rises but there is a possibility that the plating pattern may be damaged.

On the other hand, the current density of the applied current is preferably 20 ~ 100A / dm 2. When the current density is less than 20 A / dm 2, the peeling force is insufficient and the photoresist layer adhered to the surface of the conductive or insulating material does not completely peel off. However, the larger the current density, the better the peeling, but considering the limitation of the current density implementation according to the thickness of the electrodeposited photoresist layer and the rectifier capacity, it is not preferable to exceed 100 A / dm 2.

The electrodeposition photoresist stripping method according to an embodiment of the present invention may be mixed with a process using a conventional electrodeposition photoresist stripping solution. That is, the process length using the electrodeposition photoresist-only peeling liquid may be partially reduced or replaced by the peeling method according to the present invention, or may be entirely replaced. Therefore, the manufacturing cost can be reduced as much as replacing the peeling method according to the present invention.

In addition, the electrodeposition photoresist stripping method according to an embodiment of the present invention, the conductive material may be a material 110 for manufacturing the substrate 100 for mounting the electric element including the IC chip. In this case, the substrate 100 may be a lead frame for IC chip mounting. According to the present invention, in the case of a fine pitch having an internal lead interval of 30 μm or less, a suitable electrodeposition photoresist coating may be used. It is also possible to peel effectively. However, not only the lead frame but also all IC chip mounting substrates such as ball grid array (BGA) and tape automated bonding (TAB), and furthermore, electrodeposition photoresist such as IC chip and printed circuit board (PCB) as well as IC chip mounting substrate may be used. In all possible processes, the electrodeposition photoresist stripping method according to the present invention may be applied.

On the other hand, the exposure process may be laser direct imaging (hereinafter referred to as "LDI") exposure or UV exposure method. Here, in the case of applying the LDI exposure method, the electrodeposition photoresist layer adheres to the surface of the conductive material by laser heat, and thus the electrodeposition photoresist layer is not completely peeled off by the electrodeposition photoresist stripping solution, but the current application method using the electrolytic degreasing according to the present invention. When the peeling process is performed, the electrodeposition photoresist layer may be completely peeled off. In the case of applying the UV exposure method, peeling is better than in the case of the LDI exposure method when peeling with the dedicated stripping liquid, but the electrodeposition photoresist layer still remains fine. Therefore, when the peeling process is performed by the current application method using the electrolytic degreasing according to the present invention, the fine electrodeposition photoresist layer may be completely peeled off.

The peeling method of the electrodeposition photoresist according to an embodiment of the present invention can be applied for etching or plating.

3 is a cross-sectional view showing a part of a substrate manufacturing process for mounting an electric device using the electrodeposition photoresist stripping method for etching according to an embodiment of the present invention.

Referring to FIG. 3, after preparing the copper raw material 110 (a), the coating (b), the exposure and the development (c) processes of the electrodeposition photoresist 121 are performed, and the photoresist 121 is developed by the developing process. ), A half etching process (d) is performed on the copper raw material region 111 from which the) is removed. Thereafter, the photoresist 121 ′ cured by using electrolytic degreasing is peeled off (e). At this time, peeling may be performed using a dedicated stripping solution before using electrolytic degreasing. Then, a subsequent process such as a plating process (not shown) is performed.

4 and 5 are cross-sectional views showing a process for manufacturing a substrate for mounting an electric device using the electrodeposition photoresist stripping method for plating according to an embodiment of the present invention.

Referring to FIG. 4, the electrodeposition photoresist stripping process in the plating process after the etching process is applied. First, after preparing (a) the copper raw material 110, the coating (b), the exposure and the development (c) process of the DFR 122 (also electrodeposition photoresist may be performed), and then the photoresist 122 as a developing process. The half etching process (d) is performed to the copper raw material part 111 from which () was removed. Thereafter, the cured photoresist 122 'is peeled off (e) with a photoresist stripping solution (electrolytic degreasing can be used), and the electrodeposition photoresist 121 is coated (f), exposed and developed (g). To perform. Then, after the plating (130) step (h) is performed on the copper material portion 111 'from which the photoresist 121 is removed by the development process, the cured photoresist 121' is peeled off using electrolytic degreasing. (i) At this time, peeling may be performed using a dedicated stripping solution before using electrolytic degreasing. Through the above process, the substrate 100 for mounting an electric device may be manufactured.

Referring to FIG. 5, an electrodeposition photoresist stripping process is applied in a process of performing an etching process after a plating process. First, the copper raw material 110 is prepared (a), followed by the electrodeposition photoresist 121 coating (b), exposure and development (c) processes, and the copper with the photoresist 121 removed by the development process. The plating (130) process (d) is performed on the raw material portion 111 '. Thereafter, the cured photoresist 121 ′ is peeled off using electrolytic degreasing. At this time, the peeling may be performed using a dedicated stripping solution before using electrolytic degreasing as in the case of FIG. 4. Then, the DFR 122 (deposition photoresist may also be used) coating (f), exposure and development (g) processes are performed again. Subsequently, after the half etching (h) is performed on the copper raw material portion 111 from which the photoresist 122 is removed by the developing process, the photoresist 122 'cured with a photoresist stripping solution (electrolytic degreasing can be used). Peeling (i) can be carried out. Through the above process, the substrate 100 for mounting an electric device may be manufactured.

Hereinafter, the production examples and comparative production examples according to the present invention will be described in more detail.

Production Example

Using the copper raw material 110 as the conductive material, an IC chip mounting substrate 100 is manufactured according to the process diagram of FIG. First, the half-etching (d) on the copper raw material region 111 in which the photoresist 122 is removed by the development process after the coating (b), exposure and development (c) of the copper raw material 110 (b) Do this. Thereafter, the cured photoresist 122 ′ is peeled off using a stripping solution (e), and the electrodeposition photoresist 121 coating (f), LDI exposure and development (g) processes are performed. Then, plating (130) is performed on the copper raw material region 111 ′ where the photoresist is stripped by a pre-plated frame (PPF) method (h), and then the electrodeposition photoresist stripper (REMOVER R) is applied. -110, Honny Chemicals Co., Ltd, Japan) is used to exfoliate (i) the cured photoresist 121 '. Finally, an additional stripping process (i) is performed at an electric current density of 20 to 40 A / dm 2 using an electrolytic degreasing agent (Luxen cleaner 100, Lux Engineering, Korea). At this time, the concentration of the electrolytic degreasing agent is 60g / l.

Table 1 shows photographs and surface enlarged photographs showing peeling results of the IC chip mounting substrate manufactured according to the preparation example.

Comparative Production Example

Perform the same process as in Example Preparation Example, but do not perform the peeling process using the electrolytic degreasing in the last peeling step (i), the photo using a dedicated peeling liquid (REMOVER R-110, Honny Chemicals Co., Ltd, Japan) Only the resist stripping process is performed.

Table 1 shows photographs and surface enlarged photographs showing peeling results of the IC chip mounting substrate manufactured according to the comparative manufacturing example.

division Comparative Production Example Production Example




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Referring to Table 1, it can be seen that in the case of Comparative Preparation Example, the electrodeposited photoresist layer adhering to the copper raw material was not completely peeled off using the exclusive stripping solution. By performing the process it can be confirmed that the electrodeposition photoresist layer is completely peeled off.

The foregoing is a description of specific embodiments of the present invention. The above embodiments according to the present invention are not to be understood as limiting the scope of the present invention or the matter disclosed for the purpose of description, and those skilled in the art without departing from the spirit of the present invention various changes and modifications It should be understood that this is possible. It is therefore to be understood that all such modifications and alterations are intended to fall within the scope of the invention as disclosed in the following claims or their equivalents.

100: electric element mounting substrate 110: conductive material
121: electrodeposition photoresist 122: DFR
130: plating

Claims (9)

A method of peeling a photoresist by using a peeling means after a photoresist coating, exposure and development process on a conductive or insulating material,
The peeling means is performed by a current application method using electrolytic degreasing, the current has a current density of 20 ~ 100A / dm 2,
The electrolytic degreasing of the photoresist, characterized in that using an electrolytic degreasing agent containing 30 to 60% by weight of sodium hydroxide (NaOH) or potassium hydroxide (KOH), 0.001 to 10% by weight surfactant and 30 to 60% by weight erosion inhibitor Peeling method. Claim 2 has been abandoned due to the setting registration fee. The method of claim 1,
And the photoresist is an electrodeposition photoresist. delete delete delete delete delete 30 to 60% by weight of sodium hydroxide (NaOH) or potassium hydroxide (KOH), 0.001 to 10% by weight of surfactant and 30 to 60% by weight of erosion inhibitor, and after photoresist coating, exposure and development process on conductive or insulating material Electrolytic degreasing agent for photoresist stripping used to peel the photoresist. Claim 9 has been abandoned due to the setting registration fee. 9. The method of claim 8,
The photoresist is an electrolytic degreasing agent for photoresist stripping, characterized in that the electrodeposition photoresist.

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