Resin composition and prepreg, metal clad laminate and high layer count substrate including the same

Abstract

wt% of a cross-linking agent, based on a total weight of the resin mixture. The resin composition enables the production of a high layer count (HLC) substrate exhibiting an extremely low dielectric constant and an extremely low dissipation factor, thereby meeting the requirements of high-end server products.

Description

[Technical Field]

[0001] This invention relates to a resin composition, and more particularly to a resin composition for manufacturing metal clad laminates having both a low dielectric constant (Dk) and a low dielectric loss factor (Df). [Previous Technology]

[0002] Currently, high layer count (HLC) substrate materials mainly use polyphenylene ether (PPE) resin or hydrocarbon resin systems to achieve low dielectric constant / dielectric loss factor (Dk / Df) characteristics. With the development trend of high-speed computing artificial intelligence (AI) servers, the requirements for transmission rate and transmission loss of HLC substrate materials are becoming increasingly stringent. [Summary of the Invention]

[0003] As the transmission rate requirements of AI servers become higher and higher, the dielectric properties (Dk / Df) of HLC substrate materials made of PPE resin or hydrocarbon resin can no longer meet the requirements.

[0004] An embodiment of the present invention provides a polyester composition comprising a resin mixture, wherein, based on the total weight of the resin mixture, the resin mixture comprises: 15% to 75% by weight of a benzocyclobutene-containing monomer; 20% to 40% by weight of a low-dielectric resin; and 5% to 20% by weight of a crosslinking agent.

[0005] In one embodiment of the present invention, the benzocyclobutene monomer has two or more benzocyclobutene groups and two or more allyl reactive functional groups.

[0006] In one embodiment of the present invention, the low dielectric resin is polyvinylbenzene.

[0007] In one embodiment of the present invention, the crosslinking agent is 1,2-bis(vinylphenyl)ethane.

[0008] In one embodiment of the present invention, the resin mixture further includes 0% to 40% by weight of hydrocarbon resin.

[0009] In one embodiment of the present invention, the resin mixture comprises, by weight of the total resin mixture, 15% to 75% by weight of a benzocyclobutene monomer, 20% to 40% by weight of a low-dielectric resin, and 5% to 20% by weight of a crosslinking agent; by weight of 100 parts by weight of the resin mixture, the resin composition further comprises 20 phr to 50 phr of a flame retardant, 0.1 phr to 5 phr of a silane coupling agent, and 0.5 phr to 2 phr of a peroxide; and the resin composition further comprises spherical silica, wherein, by weight of the total resin composition, the content of spherical silica is 40% to 60% by weight.

[0010] In one embodiment of the present invention, the resin mixture comprises, by weight of the total resin mixture, 20% to 60% by weight of a benzocyclobutene monomer, 25% by weight of a low dielectric resin and 15% by weight of a crosslinking agent; by weight of 100 parts by weight of the resin mixture, the resin composition further comprises 30 phr of a flame retardant, 0.5 phr of a silane coupling agent and 1.0 phr of a peroxide; and the resin composition further comprises spherical silica, wherein, by weight of the total resin composition, the content of spherical silica is 45% by weight.

[0011] In one embodiment of the present invention, the resin composition further includes 0% to 40% by weight of hydrocarbon resin based on the total weight of the resin mixture.

[0012] The present invention also provides a prepreg comprising the above-described resin composition and a fibrous substrate.

[0013] The present invention also provides a metal-clad laminate, comprising the above-described prepreg and metal foil.

[0014] In one embodiment of the present invention, the metal-clad laminate has a dielectric constant of less than 3.02 and a dielectric loss factor of less than 0.00072.

[0015] The present invention also provides a high-layer substrate, comprising 20 to 30 layers of the above-described metal-clad laminate.

[0016] Based on the above, the resin composition of the present invention, by using BCB-containing monomers, can effectively reduce the Dk / Df of the fabricated high-layer-number substrate, and can even further increase the glass transition temperature (Tg) and / or reduce the coefficient of thermal expansion (CTE) of the high-layer-number substrate to meet the needs of high-end server products.

Implementation Method

[0017] Hereinafter, embodiments of the present invention will be described in detail. However, these embodiments are illustrative, and the disclosure of the present invention is not limited thereto.

[0018] In this document, the range expressed as "from one value to another" is a summary representation that avoids listing all the values ​​in the range in the specification. Therefore, the description of a particular value range covers any value within that range as well as the smaller value range defined by any value within that range, just as the arbitrary value and the smaller value range are described in the explanatory text of the specification.

[0019] The resin composition of the present invention may include a resin mixture, and the resin mixture includes at least a benzocyclobutene (BCB) monomer, a low-dielectric resin, and a crosslinking agent. Additionally, the resin composition may also include a flame retardant, a coupling agent, an accelerator, and a filler. Hereinafter, each of the above components will be described in detail. Benzocyclobutene monomer (including BCB monomer)

[0020] The BCB-containing monomer may include BCB groups and reactive functional groups. For example, the BCB-containing monomer includes two or more BCB groups and two or more reactive functional groups. In some embodiments, the reactive functional group of the BCB-containing monomer may be an allyl reactive functional group, but is not limited thereto. The number average molecular weight (Mn) of the BCB-containing monomer may be about 300 to 1000, but is not limited thereto. The amount of BCB-containing monomer added may be about 15% to 75% by weight, for example, 20% to 60% by weight, based on the total weight of the resin mixture. In some embodiments, the amount of BCB-containing monomer added is about 40% to 60% by weight, based on the total weight of the resin mixture. In some embodiments, the BCB-containing monomer has the structure shown in the following formula (1): Formula (1). Low dielectric resin

[0021] The low-dielectric resin can be poly-divinylbenzene (Poly-DVB). The number-average molecular weight (Mn) of the low-dielectric resin can be from about 4500 to 6500, but is not limited thereto. The amount of low-dielectric resin added can be from about 20% to 40% by weight, based on the total weight of the resin mixture. In some embodiments, the amount of low-dielectric resin added is from about 20% to 30% by weight, based on the total weight of the resin mixture. In some embodiments, the amount of low-dielectric resin added is from about 25% by weight, based on the total weight of the resin mixture. In some embodiments, the low-dielectric resin can be a low-dielectric resin, model LDM-03-07, purchased from Denka Corporation, Japan. Crosslinking agent

[0022] Crosslinking agents can be used to improve the degree of crosslinking of thermosetting resins and adjust the rigidity and toughness of the substrate, while also adjusting processability. The crosslinking agent can be a low-dielectric crosslinking agent, such as 1,2-bis(vinylphenyl)ethane (BVPE). The amount of crosslinking agent added can be from about 5% to 20% by weight based on the total weight of the resin mixture. In some embodiments, the amount of crosslinking agent added is from about 10% to 20% by weight based on the total weight of the resin mixture. In some embodiments, the amount of crosslinking agent added is about 15% by weight based on the total weight of the resin mixture. Flame retardant

[0023] The flame retardant can be a halogen-free flame retardant. Specific examples of halogen-free flame retardants can be phosphorus-based flame retardants. Phosphorus-based flame retardants can include phosphate ester flame retardants, such as: triphenyl phosphate (TPP), resorcinol bisphosphate (RDP), bisphenol A di(diphenyl) phosphate (BPAPP), bisphenol A di(dimethyl) phosphate (BBC), resorcinol diphosphate (CR-733S), resorcinol-bis(di-2,6-dimethylphenyl phosphate) (PX-200); phosphazene flame retardants, such as: poly(phenoxy)phosphazene (SPB-100); ammonium polyphosphate flame retardants, melamine phosphate (MPP, i.e., Melamine Polyphosphate) flame retardants, and melamine cyanurate (Melamine) flame retardants. cyanurate flame retardants; DOPO-based flame retardants, such as DOPO (e.g., structural formula (C)) flame retardants, DOPO-HQ (e.g., structural formula (D)) flame retardants, bisDOPO derivative structure (e.g., structural formula (E)) flame retardants, etc.; aluminum hypophosphite-based (e.g., structural formula (F)) flame retardants, or any combination of the foregoing flame retardants. In some embodiments, the halogen-free flame retardant is a halogen-free flame retardant, model PQ-60, purchased from Jin Yi Chemical. The resin composition may include about 20 phr to 50 phr of flame retardant per 100 parts by weight of the resin mixture. In some embodiments, the resin composition may include about 30 phr of flame retardant per 100 parts by weight of the resin mixture. Structural formula (C) Structural formula (D), m=1~4. Structural formula (E) Structural formula (F) Coupling agent

[0024] The coupling agent can enhance the compatibility and crosslinking degree of the resin composition with fiberglass cloth and powder. The coupling agent can be a silane coupling agent. Silane coupling agents may include siloxane coupling agents. Silane coupling agents may contain silane compounds. Silane compounds can be further classified according to the type of functional group as amino silane compounds, epoxide silane compounds, vinyl silane compounds, ester silane compounds, hydroxy silane compounds, isocyanate silane compounds, methacryloxy silane compounds, and acryloxy silane compounds. Based on 100 parts by weight of the resin mixture, the resin composition may include about 0.1 phr to 5 phr of silane coupling agent. In some embodiments, based on 100 parts by weight of the resin mixture, the resin composition may include about 0.5 phr of silane coupling agent. Accelerator

[0025] Peroxides may be used as accelerators. For example, the accelerator may be a peroxide accelerator, model LUPEROX F, purchased from Arkema, France. The resin composition may include about 0.5 phr to 2 phr of peroxide accelerator per 100 parts by weight of the resin mixture. In some embodiments, the resin composition may include about 1.0 phr of peroxide accelerator per 100 parts by weight of the resin mixture. Filler

[0026] Spherical silica (SiO2) can be used as a filler. For example, spherical silica can be prepared by synthesis to reduce electrical properties and maintain flowability and filling properties. In some embodiments, the spherical silica has an acrylic or vinyl surface modification. In some embodiments, the average particle size D50 of the spherical silica is about 2.0 μm to 3.0 μm. The amount of spherical silica added, based on the total weight of the resin composition, is, for example, about 40% to 60% by weight, or, for example, about 40% to 50% by weight. In some embodiments, the amount of spherical silica added, based on the total weight of the resin composition, is about 45% by weight. In some embodiments, the spherical silica is synthetic SiO2, model EQ2410-SMC, purchased from Mitsuki Chemical Co., Ltd.

[0027] It should be noted that the resin composition of the present invention can be processed into prepreg, metal-clad laminate (e.g., copper clad laminate, CCL), and high layer count (HLC) substrates according to actual design requirements. Therefore, high layer count substrates made using the resin composition of the present invention also have better reliability and can maintain the required electrical characteristics. In some embodiments, the dielectric constant of the metal-clad laminate made of the resin composition is about 2.99 to 3.02, and the dielectric loss factor is about 0.00058 to 0.00072, achieving ultra-low dielectric electrical specifications, while the Tg can be higher than about 209°C, or even higher than about 228°C. In some embodiments, the Tg of the metal-clad laminate made of the resin composition can be as high as about 228 to 243°C. In some embodiments, the coefficient of thermal expansion (CTE) of the metal-clad laminate made of the resin composition can reach about 44 ppm / °C. The resin composition of the present invention will be described in detail below by means of experimental examples. However, the following experimental examples are not intended to limit the present invention. Experimental Examples

[0028] To demonstrate that the resin composition proposed in this invention can be used to prepare metal-clad laminates with low Dk / Df, the following experimental example is specifically presented. <Preparation of Resin Composition>

[0029] The resin compositions shown in Table 1 (including Examples 1-3 and Comparative Examples 1-2) were mixed with toluene according to the formulation ratio to form a varnish of thermosetting resin composition. The varnish was impregnated with a fibrous substrate (e.g., fiberglass cloth of model SQX-Y1078C-04imp purchased from Shinetsu Corporation) at room temperature, and then dried at 130°C (impregnation machine) for several minutes to obtain a prepreg with a resin content of about 70% by weight. Subsequently, 2 to 8 prepreg layers are stacked between two metal foils (e.g., 18 μm thick copper foil), and kept at a constant temperature for 20 minutes at a pressure of, for example, 25 kg / cm² and a temperature of 85°C. Then, the temperature is increased to 220°C at a heating rate of 3°C / min, and kept at a constant temperature for 120 minutes. Finally, the temperature is slowly cooled to 130°C to obtain a metal-clad laminate (e.g., copper foil substrate) with a thickness of about 0.1 to 0.8 mm, and various properties are evaluated.

[0030] In some embodiments, when the prepreg is heated to a temperature above 200°C, the BCB groups in the BCB-containing monomer can react with alkene reactants to form group 1, and the BCB groups can also undergo self-coupling, inter-molecular coupling, intramolecular coupling, and hydrogen abstraction reactions to form groups 2 and 3. The reaction mechanism of the above reactions is shown in the following formula (2): Formula (2) Wherein, the alkene reactant can be a commonly used resin with double bonds, such as butadiene or benzene, R1 and R2 are groups in the alkene reactant, such as hydrogen, methyl, or phenyl, and n can be an integer from 1 to 10, such as 2, 4, or 6. In some embodiments, the resulting metal-clad laminate may include polymers containing group 1 and / or group 2 and / or group 3. <Evaluation Method>

[0031] The metal-clad laminates (e.g., copper foil substrates) prepared in each example and comparative example were evaluated according to the following methods, and the results are shown in Table 1. (1) Glass transition temperature (°C): The glass transition temperature Tg (°C) of the cured film of each example and comparative example was determined using a Dynamic Mechanical Analysis (DMA) according to the standard test method of ASTM E1545. (2) Coefficient of thermal expansion: The coefficient of thermal expansion in the Z direction of the cured film of each example and comparative example, i.e., Z-CTE (unit: ppm / °C), was determined using a Thermal Mechanical Analysis (TMA) according to the standard test method of IPC-TM-650 2.4.24. The temperature range for testing was 25°C to 150°C. (3) Peel strength (lb / in): The peel strength was tested using a universal tensile tester according to the standard test method of IPC-TM-650 2.4.8. (4) Water absorption rate (%): The weight change before and after heating the sample in a pressure cooker at 120 ℃ and 2 atm for 120 minutes is calculated. (5) Solder resistance at 288 ℃: The sample passes if no popcorn effect or delamination occurs after immersing it in a soldering furnace at 288 ℃ for 10 minutes. (6) Dielectric constant / loss factor: The cured film is cut into pieces with a length of 10 mm and a width of 7 mm. The dielectric constant Dk and dielectric loss factor Df of the cured film under a 10 GHz signal are determined using an HP Agilent E4991A dielectric analyzer according to the standard test method of IPC-TM-650 (Method 2.5.5.3). <Evaluation Results>

[0032] Table 1: Formulation ratios and property evaluation of Examples 1-3 and Comparative Examples 1-2 Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 match square Compare example Contains BCB monomer (wt%) 20 40 60 - - Hydrocarbon resin (wt%) 40 20 - - 60 PPE (wt%) - - - 60 - Low dielectric resin (wt%) 25 25 25 25 25 Crosslinking agent (wt%) 15 15 15 15 15 Flame retardant (PHR) 30 30 30 30 30 Peroxide accelerator (phr) 1 1 1 1 1 Silane coupling agent (PHR) 0.5 0.5 0.5 0.5 0.5 Spherical silicon dioxide (wt%) 45 45 45 45 45 Stage B curing temperature (°C) 130 130 130 130 130 Glass transfer temperature (°C) 209 228 243 221 186 Z-CTE(TMA) 63 52 44 48 70 Stripping (lb / in) (HVLP3, H-oz) 3.33 3.25 3.18 3.31 3.43 Absorbency (PCT 1 / 2 hour) (%) 0.18 0.17 0.17 0.22 0.17 Heat resistance (PCT 1 / 2 hour) pass pass pass pass pass Absorbency (PCT 2 hours) (%) 0.25 0.24 0.24 0.29 0.24 Heat resistance (PCT 2 hours) pass pass pass pass pass Dielectric constant (Dk, 10 GHz) 3.02 3.01 2.99 3.08 3.04 Dielectric loss factor (Df, 10GHz) 0.00072 0.00064 0.00058 0.0011 0.00078

[0033] Formulation information in Table 1: A. BCB-containing monomer: having the structure shown in formula (1). Formula (1) B. Hydrocarbon resin: model B-2000, purchased from Nippon Soda Co., Ltd. C. PPE: polyphenylene ether. D. Low dielectric resin: poly-divinylbenzene (Poly-DVB), model LDM-03-07, purchased from Denka Co., Ltd., Japan. E. Crosslinking agent: 1,2-bis(vinylphenyl)ethane (BVPE). F. Flame retardant: model PQ-60, purchased from Jin Yi Chemical Co., Ltd. G. Spherical silicon dioxide: model EQ2410-SMC, purchased from Sanji Co., Ltd. H. Peroxide accelerator: model LUPEROX F, purchased from Arkema, France. I. Silane coupling agent: Model KBM-503, purchased from Shin-Etsu Chemical Co., Ltd., Japan.

[0034] As shown in Table 1 above, the Dk (≤3.02) of Examples 1-3, which used 20%, 40%, and 60% BCB monomers respectively, was lower than that of Comparative Examples 1-2 (≥3.04) which did not use BCB monomers, and the Df (≤0.00072) of Examples 1-3 was lower than that of Comparative Examples 1-2 (≥0.00078). In addition, the Tg of Examples 2-3, which used 40% to 60% BCB monomers, could even reach 228°C or higher, which was higher than that of Comparative Examples 1-2 (≤221°C). Furthermore, the CTE of Example 3, which used 60% BCB monomers, could even reach 44 or lower, which was lower than that of Comparative Examples 1-2 (≥48).

[0035] In summary, the resin composition of the present invention, by using BCB-containing monomers, can effectively reduce the Dk of the manufactured metal-clad laminate to below 3.02 and the Df of the manufactured metal-clad laminate to below 0.00072. Furthermore, increasing the content of BCB monomers can further increase the Tg of the metal-clad laminate to above 228°C and / or reduce the CTE to below 44. Therefore, it can be used to manufacture high-layer-number substrates that meet the requirements of high-end server products.

[0036] Although the present invention has been disclosed above by way of embodiments, it is not intended to limit the present invention. Anyone skilled in the art can make some modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims. [Simplified Explanation of the Diagram]

[0037] None.

Claims

1. A resin composition comprising: A resin mixture, wherein, based on the total weight of the resin mixture, the resin mixture comprises: 15% to 75% by weight of a benzocyclobutene-containing monomer; 20% to 40% by weight of a low-dielectric resin; and 5% to 20% by weight of a crosslinking agent, wherein the low-dielectric resin is polyvinylbenzene.

2. The resin composition as claimed in claim 1, wherein the benzocyclobutene-containing monomer has two or more benzocyclobutene groups and two or more allyl reactive functional groups.

3. The resin composition as claimed in claim 1, wherein the crosslinking agent is 1,2-bis(vinylphenyl)ethane.

4. The resin composition as claimed in claim 1, wherein the resin mixture further comprises 0% by weight to 40% by weight of a hydrocarbon resin.

5. The resin composition as claimed in claim 1, wherein, Based on the total weight of the resin mixture, the resin mixture comprises: 15% to 75% by weight of a benzocyclobutene-containing monomer; 20% to 40% by weight of a low-dielectric resin; and 5% to 20% by weight of a crosslinking agent; based on 100 parts by weight of the resin mixture, the resin composition further comprises: 20 phr to 50 phr of a flame retardant; 0.1 phr to 5 phr of a silane coupling agent; and 0.5 phr to 2 phr of a peroxide; and the resin composition further comprises spherical silica, wherein the content of the spherical silica is 40% to 60% by weight based on the total weight of the resin composition.

6. The resin composition as claimed in claim 5, wherein, Based on the total weight of the resin mixture, the resin mixture comprises: 20% to 60% by weight of a benzocyclobutene-containing monomer; 25% by weight of a low-dielectric resin; and 15% by weight of a crosslinking agent; based on 100 parts by weight of the resin mixture, the resin composition further comprises: 30 phr of a flame retardant; 0.5 phr of a silane coupling agent; and 1.0 phr of a peroxide; and the resin composition further comprises spherical silica, wherein the content of the spherical silica is 45% by weight based on the total weight of the resin composition.

7. The resin composition as claimed in claim 6 further comprises 0% to 40% by weight of a hydrocarbon resin based on the total weight of the resin mixture.

8. A prepreg comprising a resin composition as described in any one of claims 1 to 7 and a fibrous substrate.

9. A metal-clad laminate comprising a prepreg as described in claim 8 and a metal foil.

10. The metal-clad laminate as claimed in claim 9, wherein, According to the standard test method of IPC-TM-650, the metal-clad laminate has a dielectric constant of less than 3.02 and a dielectric loss factor of less than 0.00072.

11. A high-layer substrate comprising 20 to 30 layers of metal-clad laminate as described in claim 9 or 10.

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