Circuit board pressure transmission method

Abstract

The invention relates to a circuit board processing method, in particular to a circuit board pressure transmission method, which comprises the following steps of: providing a film, arranging the film on a substrate, performing vacuum pressurization film pasting, and keeping a first electric heating temperature and a first electric heating duration in the process, so that the film is pasted on the substrate; carrying out first-stage baking on the substrate pasted with the film, and keeping a first baking temperature and a first baking duration in the process; carrying out second-stage baking on the substrate pasted with the film, and keeping a second baking temperature and a second baking duration in the process; wherein the second baking temperature is higher than the first baking temperature, and the second baking duration is longer than the first baking duration; the film comprises a resin functional layer and a carrier layer, and when the film is arranged on the substrate, one side of the resin functional layer of the film faces the substrate. By means of the structure, the film can be efficiently attached to the substrate in a high-quality mode through the arrangement of the carrier layer and the method that electric heating is matched with multi-section baking.

Description

Technical Field

[0001] The invention relates to a circuit board processing method, in particular to a circuit board pressure transmission method. Background Art

[0002] The description in this section merely provides background information related to the present disclosure and does not constitute prior art.

[0003] In the circuit board production process, it is generally necessary to attach corresponding film materials such as ABF&CBF to the substrate of the circuit board to achieve structural protection of the substrate and facilitate the next step of the processing flow. In the existing process, the method of attaching the film to the substrate is generally a hot kerosene heating and pressure transfer method, which directly applies high temperature and high pressure to the surface of the film and maintains it for a sufficient time until the film is completely attached to the substrate. However, the traditional hot kerosene heating and pressure transfer method is prone to cause poor uniformity of the layering medium, or lead to defects such as insufficient filling between lines, which is difficult to meet the quality requirements of the circuit board. At the same time, the traditional pressure transfer method has a long heating time and high heating temperature, which has a greater impact on processing efficiency.

[0004] Currently, there is no circuit board pressure transmission method that can solve the above problems. Summary of the invention

[0005] The purpose of the present invention is to provide a circuit board pressure transmission method, which can achieve efficient and high-quality film attachment to the substrate by setting a carrier layer and combining electric heating with multi-stage baking.

[0006] In order to achieve the above-mentioned object, the present invention discloses the following circuit board pressure transmission method; the circuit board pressure transmission method comprises:

[0007] Providing a film, placing the film on a substrate, and performing vacuum pressurization lamination, during which a first electric heating temperature is maintained and a first electric heating time is continued, so that the film is laminarly attached to the substrate;

[0008] Performing a first stage of baking on the substrate with the film attached thereto, during which a first baking temperature is maintained and a first baking time is continued;

[0009] Performing a second stage of baking on the substrate with the film attached thereto, during which the second baking temperature is maintained and the second baking time is continued;

[0010] Wherein, the second baking temperature is greater than the first baking temperature, and the second baking time is greater than the first baking time;

[0011] The film includes a resin functional layer and a carrier layer. When the film is disposed on the substrate, the resin functional layer of the film faces the substrate.

[0012] Furthermore, the carrier layer is set as a copper layer. After the step of "performing a second-stage baking on the substrate with the film affixed, maintaining a second baking temperature and continuing a second baking time during the process", before the subsequent circuit processing on the substrate with the film affixed, it also includes a step of etching away the copper layer.

[0013] Furthermore, the thickness of the copper layer is 12 um.

[0014] Furthermore, the film also includes a protective layer, which is arranged on the side of the resin functional layer facing away from the carrier layer. Before the step of "providing a film, arranging the film on a substrate, and performing vacuum pressurization lamination", the protective layer is torn off the film.

[0015] Furthermore, the protective layer is configured as a polypropylene film.

[0016] Furthermore, the thickness of the protective layer is between 15-35 um.

[0017] Furthermore, the first electric heating temperature is set to 60-120° C., and the first electric heating time is set to 5-10 min.

[0018] Furthermore, in the step of "performing a first-stage baking on the substrate with the film affixed thereto, during which a first baking temperature is maintained and a first baking time is continued; performing a second-stage baking on the substrate with the film affixed thereto, during which a second baking temperature is maintained and a second baking time is continued;", after the first-stage baking, the substrate is not cooled down and the second-stage baking is immediately entered, and the second baking temperature is greater than the first baking temperature, and the second baking time is greater than the first baking time.

[0019] Furthermore, the first baking temperature is set to 100° C., and the first baking time is set to 30 minutes.

[0020] Furthermore, the second baking temperature is set to 180° C., and the second baking time is set to 90 minutes.

[0021] By means of the above technical solution, the beneficial effects of the present invention are as follows:

[0022] The circuit board pressure transmission method of the present invention can be achieved by setting a carrier layer on one side of the resin functional layer of the film, and by using an electric heating method, the film is attached to a substrate, and then the substrate attached with the film is baked in sections, and the second baking temperature is greater than the first baking temperature, and the second baking time is greater than the first baking time, so that the film is more stably and completely cured on the substrate. Compared with the existing traditional hot kerosene heating pressure transmission method, the present invention takes less time and has more stable output quality.

[0023] To further understand the features and technical contents of the present invention, please refer to the following detailed description and drawings of the present invention. However, the drawings provided are only for reference and description and are not intended to limit the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of this specification or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this specification. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0025] Figure 1 It is a schematic diagram of a membrane and a substrate of a circuit board pressure transmission method provided in an embodiment of this specification;

[0026] In the figure: 1, substrate; 2, film; 21, resin functional layer; 22, carrier layer. DETAILED DESCRIPTION

[0027] In order to enable those skilled in the art to better understand the technical solutions in this specification, the technical solutions in the embodiments of this specification will be clearly and completely described below in conjunction with the drawings in the embodiments of this specification. Obviously, the described embodiments are only part of the embodiments of this specification, not all of the embodiments. Based on the embodiments in this specification, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of this specification.

[0028] The following is an explanation of the embodiments of the present invention through specific embodiments. Those skilled in the art can understand the advantages and effects of the present invention from the contents disclosed in this specification. The present invention can be implemented or applied through other different specific embodiments, and the details in this specification can also be modified and changed in various ways based on different viewpoints and applications without departing from the concept of the present invention. In addition, the drawings of the present invention are only simple schematic illustrations and are not depicted according to actual sizes. It is stated in advance. The following embodiments will further explain the relevant technical contents of the present invention in detail, but the disclosed contents are not intended to limit the scope of protection of the present invention.

[0029] It should be understood that, although the terms "first", "second", "third", etc. may be used herein to describe various components or signals, these components or signals should not be limited by these terms. These terms are mainly used to distinguish one component from another component, or one signal from another signal. In addition, the term "or" used herein may include any one or more combinations of the associated listed items depending on the actual situation.

[0030] See also Figure 1 , is a circuit board pressure transmission method of this embodiment; wherein the circuit board pressure transmission method includes:

[0031] Providing a film 2, placing the film 2 on a substrate 1, and performing vacuum pressurization lamination, during which a first electric heating temperature is maintained and a first electric heating time is continued, so that the film 2 is laminarly attached to the substrate 1;

[0032] Performing a first stage of baking on the substrate 1 with the film 2 attached thereto, during which the first baking temperature is maintained and the first baking time is continued;

[0033] Performing a second stage of baking on the substrate 1 with the film 2 attached thereto, maintaining the second baking temperature and lasting the second baking time;

[0034] The second baking temperature is greater than the first baking temperature, and the second baking time is greater than the first baking time;

[0035] The film 2 includes a resin functional layer 21 and a carrier layer 22 . When the film 2 is disposed on the substrate 1 , the resin functional layer 21 of the film 2 is disposed toward the substrate 1 .

[0036] Specifically, in the above method, when the film 2 is affixed to the substrate 1, the side of the substrate 1 corresponding to the film to be affixed faces upward, and the resin functional layer 21 of the film 2 faces downward and is directly affixed to the substrate, so that the carrier layer 22 on the other side of the resin functional layer 21 is arranged away from the substrate 1, so that the resin functional layer 21 can be fully combined with the substrate 1 during the process of electrically heated vacuum pressurized film affixing, and the carrier layer 22 plays a role in heat conduction to the resin functional layer 21 during the process of electrically heated vacuum pressurized film affixing, as well as in the subsequent first and second baking processes.

[0037] In the above-mentioned use process, first, in the first stage of vacuum pressure film lamination, after the first electric heating time, the film 2 is laminated on the substrate 1 from the side of the resin functional layer 21; then, in the second stage of the first stage of baking the substrate 1 with the film 2, after the first baking time with a relatively low temperature, the resin functional layer 21 is stably heated, initially cured and attached to one side of the substrate 1; then, in the third stage of the second stage of baking the substrate 1 with the film 2, after the second baking time with a relatively high temperature and a longer duration, the resin functional layer 21 is completely heated, completely cured and attached to one side of the substrate 1. In the above process, with the help of the setting of the carrier layer 22, the baking process of the film 2 in this embodiment can be shortened, and the resin functional layer 21 is more stably cured through the two-stage baking, which is weak first and strong later, thereby improving the processing efficiency and final output quality of the circuit board.

[0038] Furthermore, the carrier layer is set as a copper layer, and after the step of "performing a second stage baking on the substrate with the film 2, maintaining the second baking temperature and continuing the second baking time", before the subsequent circuit processing on the substrate 1 with the film 2, a step of etching and removing the copper layer is also included. Specifically, the thickness of the copper layer is 12um, and the thickness of the copper layer is half or less than the thickness of the resin functional layer 21. The purpose of its setting is to achieve a better thermal conductivity effect on the resin functional layer 21 while effectively controlling the cost. The material of the copper layer itself is cheap and easy to obtain, and the processing method is simple. After the subsequent baking is completed, the copper layer can be easily removed and cleaned with the help of a mature liquid etching process, so as to facilitate the subsequent further processing of the circuit board.

[0039] Furthermore, the film 2 further includes a protective layer (not shown in the figure), which is arranged on the side of the resin functional layer 21 away from the carrier layer 22. Before the step of "providing the film 2, arranging the film 2 on the substrate 1, and performing vacuum pressurization lamination", the protective layer is torn off the film 2. Specifically, the protective layer is set as a polypropylene film with a thickness between 15-35um. Before the film 2 is processed, the polypropylene film is attached to one side of the resin functional layer 21 of the film 2 to protect the resin functional layer 21 as the main part before processing, so as to avoid damage to the surface of the resin functional layer 21 caused by external force. At the same time, the processing technology of the polypropylene film itself is mature, and it has good resistance and is not easily corroded or degraded.

[0040] Furthermore, in the above two-stage heating, the first electric heating temperature is set to 60-120°C, the first electric heating time is set to 5-10 minutes, and at the same time, the first baking temperature is set to 100°C, the first baking time is set to 30 minutes, and the second baking temperature is set to 180°C, and the second baking time is set to 90 minutes. Specifically, in this embodiment, the second baking temperature is about 1.8 times the first baking temperature, and the second baking time is about 3 times the first baking time. The resin functional layer 21 is completely cured by the second baking, which is much stronger than the first baking.

[0041] At the same time, it should be noted that in the present embodiment, there is no cooling step between the first baking stage and the second baking stage. Specifically, the whole process is that when the substrate 1 with the film 2 is placed in place in the oven, the temperature is raised and baked. After a temperature rising curve, the film 2 reaches the first baking temperature. After continuing for a preset period of time, the temperature is further raised on the basis of the first baking temperature. After another end of the rising temperature curve, the film 2 reaches the second baking temperature. After continuing for a preset period of time, it finally enters the cooling stage.

[0042] In addition, in the above-mentioned embodiment, the resin functional layer 21 in the film 2 is set to have a thickness between 20-70 um, which is about twice the thickness of the copper layer.

[0043] The contents disclosed above are only preferred feasible embodiments of the present invention, and are not intended to limit the scope of the present invention. Therefore, all equivalent technical changes made using the contents of the present invention's specification and drawings are included in the scope of the present invention.

[0044] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other. Each embodiment focuses on the differences from other embodiments.

[0045] Although the present application has been described through embodiments, those skilled in the art will appreciate that there are many modifications and changes to the present application without departing from the spirit of the present application. It is intended that the attached embodiments include these modifications and changes without departing from the present application.

Claims

1. A circuit board pressure transmission method; characterized in that: The circuit board pressure transmission method comprises: Providing a film, placing the film on a substrate, and performing vacuum pressurization lamination, during which a first electric heating temperature is maintained and a first electric heating time is continued, so that the film is laminarly attached to the substrate; Performing a first stage of baking on the substrate with the film attached thereto, during which a first baking temperature is maintained and a first baking time is continued; Performing a second stage of baking on the substrate with the film attached thereto, during which the second baking temperature is maintained and the second baking time is continued; Wherein, the second baking temperature is greater than the first baking temperature, and the second baking time is greater than the first baking time; The film includes a resin functional layer and a carrier layer. When the film is disposed on the substrate, the resin functional layer of the film faces the substrate.

2. The circuit board pressure transmission method according to claim 1, characterized in that: The carrier layer is set as a copper layer. After the step of "performing a second-stage baking on the substrate with the film affixed, maintaining a second baking temperature and continuing a second baking time during the process", before the subsequent circuit processing on the substrate with the film affixed, it also includes a step of etching away the copper layer.

3. The circuit board pressure transmission method according to claim 2, characterized in that: The thickness of the copper layer is 12 um.

4. The circuit board pressure transmission method according to claim 1, characterized in that: The film also includes a protective layer, which is arranged on the side of the resin functional layer away from the carrier layer. Before the step of "providing a film, arranging the film on a substrate, and performing vacuum pressurization lamination", the protective layer is torn off the film.

5. The circuit board pressure transmission method according to claim 4, characterized in that: The protective layer is configured as a polypropylene film.

6. The circuit board pressure transmission method according to claim 5, characterized in that: The thickness of the protective layer is between 15-35 um.

7. The circuit board pressure transmission method according to claim 1, characterized in that: The first electric heating temperature is set to 60-120° C., and the first electric heating time is set to 5-10 min.

8. The circuit board pressure transmission method according to claim 1, characterized in that: In the step of "performing a first-stage baking on the substrate with the film affixed thereto, during which a first baking temperature is maintained and a first baking time is continued; and performing a second-stage baking on the substrate with the film affixed thereto, during which a second baking temperature is maintained and a second baking time is continued;", after the first-stage baking, the substrate is not cooled down and immediately enters the second-stage baking, and the second baking temperature is greater than the first baking temperature, and the second baking time is greater than the first baking time.

9. The circuit board pressure transmission method according to claim 8, characterized in that: The first baking temperature is set to 100° C., and the first baking time is set to 30 minutes.

10. The circuit board pressure transmission method according to claim 9, characterized in that: The second baking temperature is set to 180° C., and the second baking time is set to 90 minutes.

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