Method for boiling electrolyte membrane

Abstract

To provide a method for boiling an electrolyte membrane that enables boiling of the electrolyte membrane suitable for metal film deposition.SOLUTION: A boiling method involves heating a boiling solution L to a temperature of 90°C or higher before boiling an electrolyte membrane 13 to deaerate air dissolved in the boiling solution L, immersing the electrolyte membrane 13 in the deaerated boiling solution L, and boiling the electrolyte membrane 13 in the boiling solution L. The electrolyte membrane 13 is utilized during the process of metal film deposition onto a substrate by electrolytic plating while being in contact with the substrate.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a method for boiling an electrolyte membrane used in a film forming apparatus for forming a metal film on a substrate.

Background Art

[0002] As this type of technology, for example, Patent Document 1 proposes a film forming apparatus for forming a metal film on a substrate. The film forming apparatus includes an electrolyte membrane, and forms a metal film on the substrate by electrolytic plating in a state where the electrolyte membrane is in contact with the substrate.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, before attaching the electrolyte membrane used in the film forming apparatus to the apparatus main body of the film forming apparatus, it may be boiled with a boiling liquid such as pure water. As a result, the electrolyte membrane swells due to the boiling liquid, and metal ions in the plating solution can permeate when electrolytic plating is performed.

[0005] However, when the electrolyte membrane is boiled with the boiling liquid in a state where air dissolved in the boiling liquid adheres to the electrolyte membrane, due to temperature unevenness, the swelling state of the portion where air adheres may be different from the swelling state of other portions. As a result, since the permeability of metal ions to the electrolyte membrane is partially different, it may not be possible to stably manufacture a metal film with a uniform film thickness. In particular, it is difficult to specify the swelling state of the electrolyte membrane from the appearance, and it is difficult to grasp whether the electrolyte membrane has been boiled under appropriate boiling conditions from the appearance of the electrolyte membrane.

[0006] The present invention has been made in view of such points, and an object thereof is to provide a method for boiling an electrolyte membrane capable of boiling an electrolyte membrane suitable for forming a metal film.

Means for Solving the Problems

[0007] In view of the above problems, a method for boiling an electrolyte membrane according to the present invention is a method for boiling an electrolyte membrane used in a film forming apparatus for forming a metal film on a substrate, and the electrolyte membrane is in a state of being in contact with the substrate. It is used when forming the metal film on the substrate by electrolytic plating, and the boiling method includes a degassing step of heating the boiling liquid to a temperature of 90 ° C. or higher before boiling the electrolyte membrane to degas the air dissolved in the boiling liquid, and the degassing step. A boiling step of immersing the electrolyte membrane in the boiling liquid and boiling the electrolyte membrane with the boiling liquid.

Effects of the Invention

[0008] According to the present invention, since the air dissolved in the boiling liquid can be degassed by the degassing step, in the boiling step, the electrolyte membrane boiled with the boiling liquid is in a uniform swelling state. As a result, it is possible to boil the electrolyte membrane suitable for forming the metal film.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Mode for Carrying Out the Invention

[0010] The boiling method of the electrolyte membrane will be described below with reference to FIGS. 1 to 3. The boiling method according to the present embodiment is a boiling method of the electrolyte membrane 13 used in the film forming apparatus 1 for forming a metal film on a substrate. The electrolyte membrane 13 is attached to the apparatus main body of the film forming apparatus and is used when forming a metal film on the substrate by electrolytic plating while being in contact with the surface of the substrate.

[0011] As shown in FIG. 1, in this boiling method, first, in step S1, a boiling liquid L is introduced into a boiling water tank 20 (see FIGS. 3(a) and (b)). In this state, the electrolyte membrane 13 is not introduced into the water tank 20. The boiling liquid L can be, for example, pure water. Next, in step S2, the boiling liquid L is bubbled with nitrogen gas. Thereby, the dissolved oxygen gas can be replaced with nitrogen gas. Note that this step S2 may be omitted as long as the electrolyte membrane 13 can be boiled uniformly.

[0012] Next, in step S3, the temperature of the boiling liquid L is raised to 90° C. or higher to degas the air dissolved in the boiling liquid L. Specifically, the water tank 20 is placed on a heating and stirring device 30 and heated by a heater 31, and a stirrer 32 immersed in the boiling liquid L of the water tank 20 is moved by magnetic force, and the boiling liquid L is stirred while heating the boiling liquid L until no bubbles remain in the boiling liquid L.

[0013] Next, in step S4, the temperature of the boiling liquid L is set to a temperature below the boiling temperature by the heater of the heating and stirring device 30. Preferably, it is set to 80° C. or higher, more preferably 90° C. or higher. Next, in step S5, a capture electrolyte membrane is introduced into the boiling liquid L, and after a certain period of time has elapsed, the capture electrolyte membrane is taken out from the boiling liquid L. Thereby, foreign matters contained in the boiling liquid L can be captured by the capture electrolyte membrane. For example, when the water tank 20 is washed, foreign matters adhere to the inner wall surface of the water tank 20. In such a case, it is preferable to carry out step S5. However, if almost no foreign matter exists in the boiling liquid L, this step may be omitted.

[0014] Next, in step S6, an electrolyte membrane 13 for boiling is prepared. Specifically, as shown in FIG. 2(a), a plurality (for example, six) of electrolyte membranes 13 are attached to a frame body 40. The frame body 40 has a rectangular parallelepiped shape and has four columns 41. The columns 41 are connected by an upper long frame 42, an upper short frame 43, a lower long frame 44, and a lower short frame 45. A space S in which the above-described stirrer 32 can move is formed at the lower part of the frame body 40.

[0015] In the present embodiment, the electrolyte membranes 13 are attached inside the frame body 40 at intervals in the longitudinal direction of the frame body 40. Specifically, each electrolyte membrane 13 is attached to a pair of upper long frames 42, 42 and a pair of lower long frames 44, 44 by clips or the like. At this time, it is desirable that the electrolyte membrane 13 be attached to the frame body 40 so that no tension other than its own weight is generated in the electrolyte membrane 13 (so that creep strain does not occur).

[0016] In addition, when preparing the electrolyte membrane 13 in step S6, as shown in FIG. 2(b), a backsheet 50 made of a resin with high releasability such as polyethylene terephthalate (PET) or polyimide (PI) may be bonded to one surface of the electrolyte membrane 13. Thereby, it is possible to prevent the electrolyte membrane 13 from floating on the liquid surface of the boiling liquid L due to the weight of the backsheet 50 during boiling. However, if only the electrolyte membrane 13 is immersed in the boiling liquid L and the electrolyte membrane 13 does not float on the liquid surface of the boiling liquid L due to buoyancy, the electrolyte membrane 13 may be directly immersed in the boiling liquid L during boiling without bonding the backsheet 50 to the electrolyte membrane 13.

[0017] Next, in step S7, the electrolyte membrane 13 is immersed in the boiling liquid L degassed in step S3, and the electrolyte membrane 13 is boiled in the boiling liquid L. Specifically, in step S71, as shown in Fig. 2(a), the prepared electrolyte membrane 13 is put into the water tank 20 together with the frame body 40, and the electrolyte membrane 13 is immersed in the boiling liquid L (see Fig. 3(a)). As another method, as shown in Fig. 2(b), the electrolyte membrane 13 with the backsheet 50 bonded thereto is put into the water tank 20, and the electrolyte membrane 13 is immersed in the boiling liquid L (see Fig. 3(b)).

[0018] Next, in step S72, as shown in Fig. 3(a), the stirrer 32 immersed in the boiling liquid L in the water tank 20 is moved by magnetic force, and while stirring the boiling liquid L, the electrolyte membrane 13 is boiled in the boiling liquid L. Also, as shown in Fig. 3(b), the boiling liquid L may be stirred by the stirring device 32A. Then, in step S8, the electrolyte membrane 13 for boiling is taken out from the boiling liquid L in the water tank 20, and in step S9, the electrolyte membrane 13 for boiling is washed with water. After washing with water, the electrolyte membrane 13 is removed from the frame body 40, or the backsheet 50 is peeled off from the electrolyte membrane 13.

[0019] In this way, since the air dissolved in the boiling liquid L can be degassed in step S3, the electrolyte membrane 13 boiled in the boiling liquid L in step S7 is in a uniform swelling state. Thereby, the boiling of the electrolyte membrane 13 suitable for forming the metal film can be performed.

[0020] The following confirmation tests were conducted. First, pure water (with a conductivity of 3 μS / cm or less) was placed in a glass container (water tank) as the boiling liquid. Next, the entire amount of pure water was stirred using a stirrer (a stirrer that rotates by the force of a magnet protected with resin so as not to generate impurities). In this state, a part of a stainless steel rod with a diameter of 5 mm was immersed, and then the boiling liquid was heated in the order of 50°C, 60°C, 70°C, 80°C, and 90°C. At this time, the number of bubbles adhering to the stainless steel rod was measured. As a result, when the temperature of the boiling liquid was 50°C to 80°C, 100 or more bubbles adhered to the stainless steel rod, and when the temperature of the boiling liquid was 90°C, only about 10 bubbles adhered to the stainless steel rod. From this result, it can be seen that in step S3, the temperature of the boiling liquid suitable for degassing the air dissolved in the boiling liquid L is 90°C or higher.

Explanation of Signs

[0021] 13: Electrolyte membrane, L: Boiling liquid

Claims

【Claim 1】 A method for boiling an electrolyte membrane used in a film-forming apparatus for forming a metal film on a substrate, comprising: The electrolyte membrane is used when forming the metal film on the substrate by electrolytic plating while being in contact with the substrate; The boiling method includes: Before boiling the electrolyte membrane, a degassing step of heating a boiling liquid to a temperature of 90°C or higher to degas air dissolved in the boiling liquid; A boiling step of immersing the electrolyte membrane in the degassed boiling liquid and boiling the electrolyte membrane with the boiling liquid; A method for boiling an electrolyte membrane, characterized by including the above steps.

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