Fluorine-based substrates, copper foil substrates and printed circuit boards

Abstract

The present invention discloses a fluorine-based substrate, a copper foil substrate and a printed circuit board. The fluorine-based substrate comprises a reinforcing material layer and a fluorine-based resin layer, the reinforcing material layer comprises a base material and a first inorganic filler, the first inorganic filler is attached to the base material and dispersed in the reinforcing material layer, and the particle size of the first inorganic filler is 0.02 microns to 1 micron. The fluorine-based resin layer covers the reinforcing material layer, the fluorine-based resin layer comprises a second inorganic filler, and the particle size of the second inorganic filler is greater than 1 micron to 100 microns.

Description

Technical Field

[0001] The invention relates to a fluorine-based substrate, a copper foil substrate and a printed circuit board, and in particular to a fluorine-based substrate, a copper foil substrate and a printed circuit board suitable for high-frequency transmission. Background Art

[0002] With the advancement of technology, high-frequency transmission is an inevitable trend. In order to meet the needs of high-frequency transmission, the industry's requirements for the characteristics of circuit substrates are also increasing. Generally speaking, high-frequency substrates need to have a higher dielectric constant (Dk), a lower dielectric dissipation factor (Df), and a higher thermal conductivity, thereby having both good dielectric properties and thermal conductivity. The circuit substrate can be applied to base station antennas, satellite radars, automotive radars, wireless communication antennas, or high-frequency circuit substrates for power amplifiers.

[0003] Fluorine-based substrates are widely used in high-frequency circuit substrates because of their low dielectric loss and the ability to adjust the dielectric constant by adjusting the resin content. In the prior art, a high content of inorganic fillers is usually added to the fluorine-based substrate to improve its dielectric properties and thermal conductivity. However, when the content of inorganic fillers is too high, the adhesion between the copper foil and the fluorine-based substrate will be poor, and the copper foil will easily fall off the fluorine-based substrate during drilling or plating operations. And when the content of inorganic fillers is too high, the inorganic fillers are prone to uneven dispersion, thereby affecting the uniformity and stability of the characteristics of the fluorine-based substrate.

[0004] In order to solve the reliability problem of the above-mentioned inorganic filler, the prior art provides a technical means of setting a bonding film material between the copper foil and the fluorine-based substrate, or coating a bonding resin, so as to improve the bonding strength between the copper foil and the fluorine-based substrate. However, the method of setting a bonding film material or coating a bonding resin is costly and the manufacturing process is relatively cumbersome. In addition, the presence of the bonding film material or the bonding resin will affect the overall characteristics of the fluorine-based substrate, and it is impossible to have both high dielectric and high thermal conductivity characteristics. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a fluorine-based substrate, a copper foil substrate and a printed circuit board in view of the deficiencies in the prior art.

[0006] In order to solve the above technical problems, one of the technical solutions adopted by the present invention is to provide a fluorine-based substrate. The fluorine-based substrate includes a reinforcing material layer and a fluorine-based resin layer, the reinforcing material layer includes a base material and a first inorganic filler, the first inorganic filler is attached to the base material and dispersed in the reinforcing material layer, and the particle size of the first inorganic filler is 0.02 microns to 1 micron. The fluorine-based resin layer covers the reinforcing material layer, and the fluorine-based resin layer includes a second inorganic filler, and the particle size of the second inorganic filler is greater than 1 micron to 100 microns.

[0007] Preferably, the first inorganic filler and the second inorganic filler are silicon dioxide, titanium dioxide, aluminum hydroxide, aluminum oxide, magnesium hydroxide, magnesium oxide, calcium carbonate, boron oxide, calcium oxide, strontium titanate, barium titanate, calcium titanate, magnesium titanate, boron nitride, aluminum nitride, silicon carbide, cerium dioxide or any combination thereof.

[0008] Preferably, the thickness of the reinforcement material layer is 40 micrometers to 100 micrometers.

[0009] Preferably, the thickness of the fluorine-based resin layer is 70 micrometers to 180 micrometers.

[0010] Preferably, the substrate is a fiber cloth, and the first inorganic filler fills the pores of the fiber cloth and the gaps between the yarn bundles of the fiber cloth.

[0011] Preferably, the content of the first inorganic filler in the reinforcing material layer is 50 wt % to 80 wt %.

[0012] Preferably, the content of the second inorganic filler in the fluorine-based resin layer is 20 wt % to 70 wt %.

[0013] Preferably, the fluorine-based resin layer completely covers the reinforcing material layer.

[0014] In order to solve the above technical problems, another technical solution adopted by the present invention is to provide a copper foil substrate. The copper foil substrate includes a fluorine-based substrate and a copper foil, the copper foil is arranged on the fluorine-based substrate, and the fluorine-based substrate includes a reinforcing material layer and a fluorine-based resin layer. The reinforcing material layer includes a substrate and a first inorganic filler. Among them, the first inorganic filler is attached to the substrate and dispersed in the reinforcing material layer, and the particle size of the first inorganic filler is 0.02 microns to 1 micron. The fluorine-based resin layer covers the reinforcing material layer, and the fluorine-based resin layer includes a second inorganic filler, and the particle size of the second inorganic filler is greater than 1 micron to 100 microns.

[0015] In order to solve the above-mentioned technical problems, another technical solution adopted by the present invention is to provide a printed circuit board. The printed circuit board includes a fluorine-based substrate and a circuit layer, and the circuit layer is arranged on the fluorine-based substrate. The fluorine-based substrate includes a reinforcing material layer and a fluorine-based resin layer. The reinforcing material layer includes a base material and a first inorganic filler. Among them, the first inorganic filler is attached to the base material and dispersed in the reinforcing material layer, and the particle size of the first inorganic filler is 0.02 microns to 1 micron. The fluorine-based resin layer covers the reinforcing material layer, and the fluorine-based resin layer includes a second inorganic filler, and the particle size of the second inorganic filler is greater than 1 micron to 100 microns.

[0016] One of the beneficial effects of the present invention is that the fluorine-based substrate, copper foil substrate and printed circuit board provided by the present invention can have good dielectric properties and thermal conductivity characteristics and still have good adhesion reliability through the technical features of "a fluorine-based resin layer is coated on the outside of the reinforcing material layer", "the particle size of the first inorganic filler is adjusted to be 0.02 microns to 1 micron" and "the particle size of the second inorganic filler is adjusted to be greater than 1 micron to 100 microns".

[0017] 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

[0018] Figure 1 FIG. 1 is a side cross-sectional schematic diagram of a copper foil substrate according to a first embodiment of the present invention.

[0019] Figure 2 for Figure 1 Schematic diagram of the three-dimensional reinforcement material layer.

[0020] Figure 3 for Figure 2 An enlarged schematic diagram of part III.

[0021] Figure 4 for Figure 2 Schematic diagram of enlarged portion IV.

[0022] Figure 5 The present invention is a flow chart of the method for manufacturing the copper foil substrate.

[0023] Figure 6 FIG. 1 is a side cross-sectional schematic diagram of a copper foil substrate according to a second embodiment of the present invention.

[0024] Figure 7 FIG. 4 is a side cross-sectional schematic diagram of a copper foil substrate according to a third embodiment of the present invention. DETAILED DESCRIPTION

[0025] The following is an explanation of the implementation methods of the "fluorine-based substrate, copper foil substrate and printed circuit board" disclosed in 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 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 dimensions. It is stated in advance. The following implementation methods 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.

[0026] It should be understood that, although the terms "first", "second", "third", etc. may be used herein to describe various components, these components should not be limited by these terms. These terms are mainly used to distinguish one component from another component. In addition, the term "or" used herein may include any one or more combinations of the associated listed items depending on the actual situation.

[0027] See also Figure 1 As shown, Figure 1 It is a side cross-sectional schematic diagram of the copper foil substrate of the first embodiment of the present invention. The present invention provides a copper foil substrate 1, which includes a reinforcing material layer 10, a fluorine-based resin layer 20 and a copper foil 30. The copper foil substrate 1 of the present invention has both excellent dielectric properties and good thermal conductivity properties, and can be applied to high-frequency circuit boards. In addition, the present invention can make the copper foil substrate 1 have a higher peel strength without providing an adhesive film layer or coating an adhesive resin. Even in the subsequent drilling or plating process, the copper foil 30 still has good adhesive reliability and will not easily separate from the fluorine-based resin layer 20.

[0028] In this embodiment, the reinforcing material layer 10 includes a substrate 11 and a first inorganic filler 12. The thickness of the reinforcing material layer 10 is 40 microns to 100 microns. The substrate 11 can be a fiber cloth or insulating paper, but is not limited thereto. The material of the substrate 11 can be glass fiber, carbon fiber, graphite fiber, alumina fiber, silicon carbide fiber, silicon nitride fiber, boron fiber or a combination thereof. Preferably, the material of the substrate 11 can be glass fiber, but is not limited thereto.

[0029] The first inorganic filler 12 is attached to the substrate 11 and evenly dispersed in the part of the reinforcing material layer 10 except the substrate 11. The particle size of the first inorganic filler 12 is 0.02 micrometers to 1 micrometer (for example, a positive integer between 20 and 1000 nanometers). The first inorganic filler 12 can be silicon dioxide, titanium dioxide, aluminum hydroxide, aluminum oxide, magnesium hydroxide, magnesium oxide, calcium carbonate, boron oxide, calcium oxide, strontium titanate, barium titanate, calcium titanate, magnesium titanate, boron nitride, aluminum nitride, silicon carbide, cerium dioxide or any combination thereof.

[0030] Among them, silicon dioxide can be molten or crystalline silicon dioxide. If the dielectric properties of the entire copper foil substrate 1 are considered, molten silicon dioxide is more preferred. Titanium dioxide can be rutile, anatase or brookite titanium dioxide. If the dielectric properties of the entire copper foil substrate 1 are considered, rutile titanium dioxide is more preferred.

[0031] Please refer to the combined Figures 2 to 4 As shown, Figure 2 Schematic diagram of the reinforcing material layer 10 in the present invention. Figure 3 and Figure 4 They are Figure 2 In this embodiment, the substrate 11 is a fiber cloth. If the structure of the reinforcing material layer 10 is further observed, it can be found that a portion of the first inorganic filler 12 fills the pores of the fiber cloth (such as Figure 2 The other part of the first inorganic filler 12 is filled in the gaps at the end or middle of the yarn bundle 111 of the fiber cloth (as shown in FIG. Figure 3 , 4 As shown). The present invention can improve the structural strength of the substrate 11 itself and further improve the dielectric constant stability and dimensional stability of the reinforcement material layer 10 on the XZ plane by using the first inorganic filler 12.

[0032] Please see again Figure 1 As shown, the fluorine resin layer 20 covers the reinforcing material layer 10. Specifically, the fluorine resin layer 20 can be formed on opposite sides of the reinforcing material layer 10 and sandwiched outside the reinforcing material layer 10 (such as Figure 1 The fluorine resin layer 20 may also be completely coated outside the reinforcing material layer 10. The thickness of the fluorine resin layer 20 is 70 microns to 180 microns.

[0033] The fluorine resin layer 20 includes a second inorganic filler 21, the particle size of the second inorganic filler 21 is greater than 1 micron to 100 microns (for example, a positive integer between 1 and 100 microns), and the second inorganic filler 21 is disposed on the reinforcing material layer 10 and dispersed in the fluorine resin layer 20. The second inorganic filler 21 can be silicon dioxide, titanium dioxide, aluminum hydroxide, aluminum oxide, magnesium hydroxide, magnesium oxide, calcium carbonate, boron oxide, calcium oxide, strontium titanate, barium titanate, calcium titanate, magnesium titanate, boron nitride, aluminum nitride, silicon carbide, cerium dioxide or any combination thereof.

[0034] The structure formed by the aforementioned reinforcing material layer 10 and the fluorine-based resin layer 20 is collectively referred to as a fluorine-based substrate. The first inorganic filler 12 and the second inorganic filler 21 in the fluorine-based substrate may be the same or different materials. In one embodiment, when the first inorganic filler 12 and the second inorganic filler 21 are the same material, the compatibility between the reinforcing material layer 10 and the fluorine-based resin layer 20 can be improved to increase the peel strength of the copper foil substrate 1. In another embodiment, the first inorganic filler 12 and the second inorganic filler 21 may be different materials, and the dielectric constant or other properties of the copper foil substrate 1 may be adjusted by selecting inorganic fillers of different materials.

[0035] The copper foil 30 is disposed on the fluorine resin layer 20, and different numbers of copper foils 30 can be selected according to the type of the copper foil substrate 1. For example, a single-sided copper foil substrate (such as Figure 1 If two copper foils 30 are set on the fluorine-based substrate, a double-sided copper foil substrate (such as Figure 7 The specific structure of the double-sided copper foil substrate will be described in detail later.

[0036] Please refer to the combined Figure 1 , 5 As shown, Figure 5 Flow chart of the method for preparing the copper foil substrate 1 of the present invention. The method for preparing the copper foil substrate 1 comprises the following steps: First, a substrate 11 is provided (step S100). A first solution is applied on the substrate 11 (step S102). The substrate 11 with the first solution applied is dried to form a reinforcing material layer 10 (step S104).

[0037] In step S102, the first solution is applied to the substrate 11 by immersing the substrate 11 in the first solution or coating the substrate 11 with the first solution. The first solution includes: a first inorganic filler 12 with a concentration of 50wt% to 80wt%, a fluorine-based resin with a concentration of 10wt% to 40wt%, a fluorine-containing polymer with a concentration of 1wt% to 10wt%, a low molecular weight polytetrafluoroethylene with a concentration of 0.1wt% to 50wt%, and an impregnation aid with a concentration of 0.1wt% to 10wt%.

[0038] In the present embodiment, the fluorine-based resin may be a polytetrafluoroethylene resin, but is not limited thereto. The fluorine-containing polymer may be a tetrafluoroethylene / perfluoroalkoxy vinyl ether copolymer (PFA) or a perfluoroethylene propylene copolymer (FEP). Low molecular weight polytetrafluoroethylene may be prepared by thermal cracking degradation or radiation degradation, and the molecular weight of the low molecular weight polytetrafluoroethylene is 2000 to 200000. Preferably, the molecular weight of the low molecular weight polytetrafluoroethylene is 10000 to 100000. The impregnation aid may be, but is not limited to, hydroxyethyl cellulose, nitrocellulose, polymethyl styrene, polymethyl methacrylate, polyethylene glycol or any combination thereof. The addition of an impregnation aid may adjust the viscosity of the resin composition, and may avoid the roughness of the surface due to excessive viscosity, thereby affecting the film flatness of the reinforcing material layer 10. Or it may avoid the formation of holes on the surface of the reinforcing material layer 10 due to low viscosity.

[0039] After the first solution is applied to the substrate 11, the first inorganic filler 12 will fill the gaps in the substrate 11 and be evenly dispersed on the substrate 11. The use of the first inorganic filler 12 can enhance the structural strength of the substrate 11 itself and enhance the uniformity of the dielectric constant of the reinforcing material layer 10 on the XZ plane. Since the first inorganic filler 12 fills the gaps in the substrate 11, there is less of a problem of affecting the bonding reliability due to an excessively high content of the first inorganic filler 12.

[0040] In step S104, the method of drying the substrate 11 with the first solution applied thereto to form the reinforcing material layer 10 may include three stages of temperature raising steps: drying the substrate 11 at a temperature of 80° C. to 120° C., baking at a temperature of 200° C. to 240° C., and sintering at a temperature of 340° C. to 360° C., and each step of drying, baking, and sintering is maintained for at least 20 minutes. However, the present invention is not limited thereto.

[0041] The method for preparing the copper foil substrate 1 includes: applying a second solution on the reinforcing material layer 10 (step S106 ), and drying the reinforcing material layer 10 with the second solution applied thereon to form a fluorine-based resin layer 20 on the reinforcing material layer 10 to obtain a fluorine-based substrate (step S108 ).

[0042] In step S106, the step of applying the second solution on the reinforcing material layer 10 can be to immerse the reinforcing material layer 10 in the second solution, or to coat the second solution on the outside of the reinforcing material layer 10. The second solution includes a second inorganic filler 21 with a concentration of 20wt% to 70wt%, a fluorine-based resin with a concentration of 10wt% to 70wt%, a fluorine-containing polymer with a concentration of 1wt% to 10wt%, a low molecular weight polytetrafluoroethylene with a concentration of 0.1wt% to 50wt%, and an impregnation aid with a concentration of 0.1wt% to 10wt%. The fluorine-based resin, fluorine-containing polymer, low molecular weight polytetrafluoroethylene and impregnation aid in the second solution are similar to those in the first solution, so they are not repeated here.

[0043] By adjusting the content of the fluorine-containing polymer, the fluorine-based resin layer 20 can have good processability. For example, if the amount of the fluorine-containing polymer in the fluorine-based resin layer 20 is greater than 10wt%, glue flow is likely to occur during the hot pressing of the copper foil, which affects the processability and thickness uniformity of the copper foil substrate 1. If the amount of the fluorine-containing polymer in the fluorine-based resin layer 20 is less than 1wt%, the copper foil 30 is likely to peel off.

[0044] Low molecular weight polytetrafluoroethylene (molecular weight of 2000 to 200000, preferably 10000 to 100000) has better arrangement ability due to its shorter molecular chain. Therefore, when sintering or pressing process is performed at an appropriate temperature, the addition of low molecular weight polytetrafluoroethylene can increase the crystallinity of the fluorine resin layer 20, thereby improving the thermal conductivity of the fluorine resin layer 20.

[0045] After the second solution is applied on the reinforcing material layer 10 , the second inorganic filler 21 is disposed on the reinforcing material layer 10 .

[0046] In step S108, the method of drying the reinforcing material layer 10 with the second solution applied thereto to obtain the fluorine-based substrate may include three stages of temperature increase steps: drying the reinforcing material layer 10 at a temperature of 80°C to 120°C, baking at a temperature of 200°C to 240°C, and sintering at a temperature of 340°C to 360°C in sequence. In each step of drying, baking, and sintering, at least 20 minutes are maintained. However, the present invention is not limited thereto.

[0047] In other embodiments, step S106 and step S108 may be repeated multiple times. That is, the steps of applying the second solution on the reinforcing material layer 10 and drying are repeated to form a fluorine-based resin layer 20 of a specific thickness. Since the thickness of the fluorine-based resin layer 20 can be adjusted according to demand, in the present invention, the preferred thickness of the fluorine-based resin layer 20 is 50 microns to 150 microns (e.g., a positive integer between 50 and 150 microns).

[0048] Finally, the method for preparing the copper foil substrate 1 includes: placing a copper foil 30 on the fluorine resin layer 20 of the fluorine substrate to obtain a copper foil substrate 1 (step S110). The copper foil 30 is placed at a temperature of 340°C to 360°C and a pressure of 45kg / cm 2 Up to 55kg / cm 2 The copper foil 30 is laminated on the fluorine resin layer 20 by continuous hot pressing for 2 hours. Then, the temperature is firstly lowered to 250°C at a cooling rate of 1°C / min to 4°C / min, and then the temperature is lowered from 250°C to room temperature at a cooling rate of 10°C / min, thereby improving the crystallinity of the fluorine resin layer 20 and improving the thermal conductivity of the copper foil substrate 1. However, the present invention is not limited thereto.

[0049] According to the above content, by executing the aforementioned steps S100 to S104, a reinforcing material layer 10 can be formed. By executing the aforementioned steps S106 and S108, a fluorine-based resin layer 20 can be formed outside the reinforcing material layer 10. It is worth noting that the preparation method of the fluorine-based substrate is not limited to the above. In actual operation, the aforementioned steps S100 to S108 can be repeatedly performed to form a plurality of structures consisting of a fluorine-based resin layer 20 / reinforcing material layer 10 / fluorine-based resin layer 20. In addition, a plurality of structures consisting of a fluorine-based resin layer 20 / reinforcing material layer 10 / fluorine-based resin layer 20 can be stacked to achieve a target thickness, such as Figure 6 shown.

[0050] Figure 6 This is a copper foil substrate 1 of the second embodiment of the present invention, wherein the fluorine-based substrate is composed of a fluorine-based resin layer 20 / reinforcement material layer 10 / fluorine-based resin layer 20 / fluorine-based resin layer 20 / reinforcement material layer 10 / fluorine-based resin layer 20 stacked in sequence, and a copper foil 30 is formed on the fluorine-based resin layer 20 to form a single-sided copper foil substrate.

[0051] In addition, the above-mentioned preparation method can also be used to prepare a double-sided copper foil substrate, that is, a copper foil 30 is disposed on each of the two opposite sides of the fluorine-based substrate. Figure 7 As shown, Figure 7 FIG. 4 is a side cross-sectional schematic diagram of a copper foil substrate according to a third embodiment of the present invention. Figure 7 The copper foil substrate 1 and Figure 1 The difference between the copper foil substrate 1 and the fluorine-based substrate is that a copper foil 30 is disposed on two opposite sides of the fluorine-based substrate. Figure 7 The structures of the reinforcing material layer 10, the fluorine-based resin layer 20 and the copper foil 30 are similar to those described above and will not be described in detail herein.

[0052] In addition, in other embodiments, the copper foil substrate 1 can be further etched and developed to pattern the copper foil 30 to form a circuit layer, thereby obtaining a printed circuit board with high dielectric and high thermal conductivity characteristics, and can be suitable for high frequency transmission.

[0053] In order to verify that the copper foil substrate of the present invention has both high dielectric and high thermal conductivity properties, the present invention prepared different copper foil substrates 1, and the process parameters of each copper foil substrate 1 are shown in Table 1 below. The physical properties of each copper foil substrate 1 are evaluated, and the evaluation method includes:

[0054] (1) Thermal conductivity analysis test: According to the ASTM-D5470 test method, a thermal conductivity analysis test was performed using an interface material thermal resistance and thermal conductivity coefficient measuring instrument (Model LW-9389, Ruiling Technology Co., Ltd., Taiwan, China).

[0055] (2) Dielectric constant (10 GHz): A dielectric analyzer (HP Agilent E4991A) was used to measure the dielectric constant at a frequency of 10 GHz.

[0056] (3) Dielectric loss (10 GHz): A dielectric analyzer (HP Agilent E4991A) was used to test the dielectric loss at a frequency of 10 GHz.

[0057] (4) Peel strength test: According to the IPC-TM-650-2.4.8 test method, the peel strength of the copper foil substrate is tested.

[0058] Table 1: Preparation conditions and physical property evaluation of copper foil substrates of Examples 1 to 4 and Comparative Examples 1 to 4.

[0059]

[0060]

[0061] According to the results in Table 1, the present invention can prepare a fluorine-based substrate, a copper foil substrate 1 and a printed circuit board having high dielectric properties, high thermal conductivity and high peel strength by adjusting the particle size of the first inorganic filler 12 in the reinforcing material layer 10. Specifically, the thermal conductivity coefficient of the copper foil substrate 1 of the present invention is 0.7W / mK to 1.8W / mK, the dielectric constant (10GHz) is 3.5 to 11.4, the dielectric loss (10GHz) is 0.0015 to 0.0020, and the peel strength is 10.3lb / in to 13.3lb / in.

[0062] [Beneficial Effects of Embodiments]

[0063] One of the beneficial effects of the present invention is that the fluorine-based substrate, copper foil substrate 1 and printed circuit board provided by the present invention can have good dielectric properties and thermal conductivity characteristics, and still have good adhesion reliability through the technical features of "fluorine-based resin layer 20 covering the reinforcing material layer 10", "regulating the particle size of the first inorganic filler 12 to be 0.02 microns to 1 micron" and "regulating the particle size of the second inorganic filler 21 to be greater than 1 micron to 100 microns".

[0064] Furthermore, the present invention, through the technical features of "regulating the content of the first inorganic filler 12 in the reinforcing material layer 10" and "regulating the content of the second inorganic filler 21 in the fluorine-based resin layer 20", allows an appropriate amount of the first inorganic filler 12 and the second inorganic filler 21 to be attached to the substrate 11, while improving the dielectric properties and thermal conductivity characteristics, while still maintaining the adhesion reliability of the copper foil substrate 1 and the printed circuit board.

[0065] The contents disclosed above are only preferred feasible embodiments of the present invention, and are not intended to limit the protection scope of the claims of the present invention. Therefore, all equivalent technical changes made using the contents of the present invention description and drawings are included in the protection scope of the claims of the present invention.

Claims

1. A fluorine-based substrate, characterized in that: The fluorine-based substrate comprises: a reinforcing material layer, comprising a substrate and a first inorganic filler, wherein the first inorganic filler is attached to the substrate and dispersed in the reinforcing material layer; wherein the particle size of the first inorganic filler is 0.02 micrometers to 1 micrometer; and A fluorine-based resin layer, which covers the reinforcing material layer, wherein the fluorine-based resin layer is formed by immersing the reinforcing material layer in a second solution, wherein the second solution includes a second inorganic filler with a concentration of 20wt% to 70wt%, a polytetrafluoroethylene resin with a concentration of 10wt% to 70wt%, a fluorine-containing polymer with a concentration of 1wt% to 10wt%, a low molecular weight polytetrafluoroethylene with a concentration of 0.1wt% to 50wt% and an impregnation aid with a concentration of 0.1wt% to 10wt%, the particle size of the second inorganic filler is 6 microns to 100 microns, and is greater than 6 microns; wherein the fluorine-containing polymer is a tetrafluoroethylene / perfluoroalkoxy vinyl ether copolymer or a perfluoroethylene propylene copolymer.

2. The fluorine-based substrate according to claim 1, characterized in that: The first inorganic filler and the second inorganic filler are silicon dioxide, titanium dioxide, aluminum hydroxide, aluminum oxide, magnesium hydroxide, magnesium oxide, calcium carbonate, boron oxide, calcium oxide, strontium titanate, barium titanate, calcium titanate, magnesium titanate, boron nitride, aluminum nitride, silicon carbide, cerium dioxide or any combination thereof.

3. The fluorine-based substrate according to claim 1, characterized in that: The thickness of the reinforcement material layer is 40 micrometers to 100 micrometers.

4. The fluorine-based substrate according to claim 1, characterized in that: The thickness of the fluorine-based resin layer is 70 micrometers to 180 micrometers.

5. The fluorine-based substrate according to claim 1, characterized in that: The substrate is a fiber cloth, and the first inorganic filler fills the pores of the fiber cloth and the gaps between the yarn bundles of the fiber cloth.

6. The fluorine-based substrate according to claim 1, characterized in that: The content of the first inorganic filler in the reinforcing material layer is 50 wt % to 80 wt %.

7. The fluorine-based substrate according to claim 1, characterized in that: The content of the second inorganic filler in the fluorine-based resin layer is 20 wt % to 70 wt %.

8. The fluorine-based substrate according to claim 1, characterized in that: The fluorine-based resin layer completely covers the reinforcing material layer.

9. A copper foil substrate, characterized in that: The copper foil substrate comprises: A fluorine-based substrate comprising: a reinforcing material layer, comprising a substrate and a first inorganic filler; wherein the first inorganic filler is attached to the substrate and dispersed in the reinforcing material layer, and the particle size of the first inorganic filler is 0.02 micrometers to 1 micrometer; and a fluorine-based resin layer covering the reinforcing material layer, wherein the fluorine-based resin layer is formed by immersing the reinforcing material layer in a second solution, wherein the second solution comprises a second inorganic filler with a concentration of 20wt% to 70wt%, a polytetrafluoroethylene resin with a concentration of 10wt% to 70wt%, a fluorine-containing polymer with a concentration of 1wt% to 10wt%, a low molecular weight polytetrafluoroethylene with a concentration of 0.1wt% to 50wt%, and an impregnation aid with a concentration of 0.1wt% to 10wt%, wherein the particle size of the second inorganic filler is 6 microns to 100 microns, and is greater than 6 microns; wherein the fluorine-containing polymer is a tetrafluoroethylene / perfluoroalkoxy vinyl ether copolymer or a perfluoroethylene propylene copolymer; and A copper foil is disposed on the fluorine-based substrate.

10. A printed circuit board, characterized in that: The printed circuit board comprises: A fluorine-based substrate comprising: a reinforcing material layer, comprising a substrate and a first inorganic filler; wherein the first inorganic filler is attached to the substrate and dispersed in the reinforcing material layer, and the particle size of the first inorganic filler is 0.02 micrometers to 1 micrometer; and a fluorine-based resin layer covering the reinforcing material layer, wherein the fluorine-based resin layer is formed by immersing the reinforcing material layer in a second solution, wherein the second solution comprises a second inorganic filler with a concentration of 20wt% to 70wt%, a polytetrafluoroethylene resin with a concentration of 10wt% to 70wt%, a fluorine-containing polymer with a concentration of 1wt% to 10wt%, a low molecular weight polytetrafluoroethylene with a concentration of 0.1wt% to 50wt%, and an impregnation aid with a concentration of 0.1wt% to 10wt%, wherein the particle size of the second inorganic filler is 6 microns to 100 microns, and is greater than 6 microns; wherein the fluorine-containing polymer is a tetrafluoroethylene / perfluoroalkoxy vinyl ether copolymer or a perfluoroethylene propylene copolymer; and A circuit layer is disposed on the fluorine-based substrate.

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