Film coating method of circuit substrate

Abstract

The coating method of the circuit substrate comprises the following steps: gasifying an acrylate monomer: heating to convert the acrylate monomer into acrylate gas; the circuit substrate is placed in a vacuum cavity, and the air pressure of the vacuum cavity is adjusted to be first air pressure; the acrylic ester gas and nitrogen or argon are sequentially introduced into the vacuum cavity, the vacuum cavity is adjusted to be in a second air pressure, and the second air pressure is smaller than the first air pressure; and controlling the power and the reaction time in the vacuum cavity to enable the acrylic ester gas to generate plasma polymerization deposition, and forming a hole sealing film on the circuit substrate. The uniform hole sealing film is formed on the circuit substrate, so that the manufacturing defects of the circuit substrate can be overcome, the corrosion resistance is improved, and the problem of non-uniform coating is solved.

Description

Technical Field

[0001] The invention relates to the field of circuit substrate manufacturing, and in particular to a coating method for a circuit substrate. Background Art

[0002] The circuit substrates used in the electronics industry are usually copper-clad laminates, in which a layer of polyester film is usually bonded to the surface of the copper foil. Due to the low strength of the polyester film, it is easy to be etched and scratched or even peeled off under the action of external force, resulting in reduced performance of the copper-clad laminate. In order to protect the copper-clad laminate and achieve heat dissipation, a layer of heat dissipation paint is usually applied on its surface. Existing heat dissipation paints are usually prepared by directly adding inorganic heat dissipation fillers to the resin and then stirring and mixing. However, since the inorganic heat dissipation fillers themselves are easy to agglomerate during the stirring and mixing process, the coating is unevenly dispersed. At the same time, the particle size of the filler also affects the dispersibility of the coating, thereby affecting the performance of the coating.

[0003] Therefore, it is necessary to provide a coating method for a circuit substrate to form an improved thin film on the circuit substrate to overcome the above defects. Summary of the invention

[0004] The object of the present invention is to provide an improved coating method for circuit substrates, forming a uniform sealing film on the circuit substrate, thereby compensating for the manufacturing defects of the circuit substrate, improving the corrosion resistance, and solving the problem of uneven coating.

[0005] To achieve the above object, the coating method of the circuit substrate of the present invention comprises the following steps:

[0006] Gasification of acrylate monomers: heating to convert acrylate monomers into acrylate gas;

[0007] Placing the circuit substrate in a vacuum chamber, and adjusting the vacuum chamber pressure to a first pressure;

[0008] sequentially introducing the acrylic ester gas and nitrogen or argon gas into the vacuum chamber to adjust the vacuum chamber to a second pressure, wherein the second pressure is less than the first pressure; and

[0009] The power and reaction time in the vacuum chamber are controlled to cause the acrylate gas to undergo plasma polymerization deposition to form a sealing film on the circuit substrate.

[0010] Compared with the prior art, the present invention adopts plasma polymerization deposition technology, utilizes the glow discharge to generate plasma after the acrylic acid ester monomer is gasified, breaks the chemical bonds of the gaseous monomer to generate active groups, and the active groups polymerize and deposit on the surface of the circuit substrate, including in the rough micropores therein, to form a layer of uniform micron or nanometer-level sealing film, thereby compensating for the manufacturing defects of the circuit substrate, improving corrosion resistance, and solving the problem of uneven coating. Moreover, the present invention has a simple operation process, high timeliness, and low energy consumption, and is suitable for popularization and use in production.

[0011] Preferably, the acrylate monomer is gasified including: placing the acrylate monomer in a heating furnace at a heating temperature of 120° C. to 125° C. Preferably, the heating time is 1 to 2 hours.

[0012] Preferably, the first gas pressure is 25-30 mTorr.

[0013] Preferably, the flow rate of the acrylic ester gas is 1-5 sccm.

[0014] Preferably, the second gas pressure is 10-15 mTorr.

[0015] Preferably, the power in the vacuum chamber is 20-35 W, and the reaction time is 60-240 seconds. DETAILED DESCRIPTION

[0016] The coating method of the circuit substrate of the present invention is further described below in conjunction with the embodiments, but the present invention is not limited thereby. The method of the present invention is intended to provide a coating method of the circuit substrate to compensate for the manufacturing defects of the circuit substrate, improve the corrosion resistance, and solve the problem of uneven coating.

[0017] In one embodiment of the coating method of the circuit substrate of the present invention, the following steps are included:

[0018] Gasification of acrylate monomers: heating to convert acrylate monomers into acrylate gas;

[0019] Placing the circuit substrate in a vacuum chamber, and adjusting the vacuum chamber pressure to a first pressure;

[0020] sequentially introducing the acrylic ester gas and nitrogen or argon gas into the vacuum chamber to adjust the vacuum chamber to a second pressure, wherein the second pressure is less than the first pressure; and

[0021] The power and reaction time in the vacuum chamber are controlled to cause the acrylate gas to undergo plasma polymerization deposition to form a sealing film on the circuit substrate.

[0022] The present invention adopts plasma polymerization deposition technology, utilizes the glow discharge after the acrylic acid ester monomer is gasified to generate plasma, breaks the chemical bonds of the gaseous monomer to generate active groups, and the active groups polymerize and deposit on the surface of the circuit substrate, including in the rough micropores therein to form a layer of uniform micron or nanometer-level sealing film, thereby compensating for the manufacturing defects of the circuit substrate, improving corrosion resistance, and solving the problem of uneven coating. Moreover, the present invention has a simple operation process, high timeliness, and low energy consumption, and is suitable for popularization and use in production.

[0023] The plasma polymerization deposition technology is simple, convenient and fast. The energy generated by radio frequency low-pressure glow discharge is about 5eV, which will cause the breakage of molecular covalent bonds (4eV). The active particles such as electrons, particles, free radicals and other excited molecules in the plasma are used to polymerize the monomers. The present invention combines plasma polymerization deposition technology with acrylic ester gas to deposit a uniform sealing film on the surface of the substrate, which has significant advantages over the heat dissipation coating of the prior art.

[0024] As a preferred embodiment, the acrylic acid ester monomer is placed in a heating furnace at a heating temperature of 120° C. to 125° C. to convert the acrylic acid ester into a gaseous state. The heating time is preferably 1 to 2 hours.

[0025] The circuit substrate is placed in a vacuum chamber in advance, the chamber is evacuated, and the first gas pressure is adjusted to 25-30 mTorr.

[0026] Then, firstly, acrylate gas is introduced, and the flow rate of acrylate gas is controlled to be 1-5 sccm, and then nitrogen or argon gas is introduced into the vacuum chamber, and the second gas pressure of the vacuum chamber is adjusted to 10m-15mTorr. The reduced gas pressure in the vacuum chamber is particularly suitable for subsequent plasma polymerization deposition.

[0027] Next, adjust the power in the vacuum chamber to 20-35W and the reaction time to 60-240 seconds.

[0028] The power of the vacuum chamber is 20W-35W, and the reaction time is 60s-2400s. Glow discharge generates plasma, which breaks the chemical bonds of the acrylic ester gas to generate active groups, which form a uniform sealing film on the surface of the circuit substrate.

[0029] Finally, the circuit board is removed and the operation is completed.

[0030] In summary, the present invention adopts plasma polymerization deposition technology, utilizes the glow discharge to generate plasma after the acrylic acid ester monomer is gasified, breaks the chemical bonds of the gaseous monomer to generate active groups, and the active groups polymerize and deposit on the surface of the circuit substrate, including in the rough micropores therein to form a layer of uniform micrometer or nanometer-level sealing film, thereby compensating for the manufacturing defects of the circuit substrate, improving corrosion resistance, and solving the problem of uneven coating. Moreover, the present invention has a simple operation process, high timeliness, and low energy consumption, and is suitable for popularization and use in production.

[0031] The above disclosure is only a preferred embodiment of the present invention, which certainly cannot be used to limit the scope of rights of the present invention. Therefore, equivalent changes made according to the scope of the patent application of the present invention are still within the scope covered by the present invention.

Claims

1. A coating method for a circuit substrate, characterized in that: The following steps are involved: Gasification of acrylate monomers: heating to convert acrylate monomers into acrylate gas; Placing the circuit substrate in a vacuum chamber, and adjusting the vacuum chamber pressure to a first pressure; Introducing the acrylic ester gas and nitrogen or argon gas into the vacuum chamber in sequence, and adjusting the vacuum chamber to a second pressure, wherein the second pressure is less than the first pressure; as well as The power and reaction time in the vacuum chamber are controlled to cause the acrylate gas to undergo plasma polymerization deposition to form a sealing film on the circuit substrate.

2. The method for coating a circuit substrate according to claim 1, wherein: The acrylate monomer gasification includes: placing the acrylate monomer in a heating furnace at a heating temperature of 120° C.-125° C.

3. The method for coating a circuit substrate according to claim 2, wherein: The heating time is 1-2 hours.

4. The method for coating a circuit substrate according to claim 1, wherein: The first gas pressure is 25-30 mTorr.

5. The method for coating a circuit substrate according to claim 1, wherein: The flow rate of the acrylic ester gas is 1-5 sccm.

6. The method for coating a circuit substrate according to claim 1, wherein: The second gas pressure is 10-15 mTorr.

7. The method for coating a circuit substrate according to claim 1, wherein: The power in the vacuum chamber is 20-35W, and the reaction time is 60-240 seconds.