High-Frequency Circuit Board Coating Process for 5G Signal Transmission
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional high-frequency circuit boards, particularly those using polyimide substrates, face challenges with high-frequency transmission loss, moisture absorption, and poor structural reliability, making them unsuitable for the increasing demands of 5G technology products.
Innovation Solution
A method for forming a novel material layer structure on high-frequency circuit boards involves coating a copper foil with a synthetic liquid film and subsequent heating to create a cured film, followed by applying a synthetic liquid high-frequency material layer and further heating to achieve a semi-cured state, optimizing the structure for high-speed signal transmission with materials like MPI, LCP, TFP, or PTFE films.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional polyimide substrate is used for soft board, then the soft board can be manufactured with existing processes, but the high-frequency transmission loss is serious and reliability is poor
Solution Approach 1:
The patent changes the material parameters by replacing conventional polyimide substrate with liquid crystal polymer (LCP) substrate. This material substitution fundamentally alters the dielectric properties, reducing the dielectric constant from 3.2-3.8 to 2.7-3.0 and loss factor from 0.005-0.01 to 0.002-0.004, thereby resolving the high-frequency transmission loss issue while maintaining manufacturability through adapted coating processes
Solution Approach 2:
The patent employs composite material structure by combining LCP substrate with copper foil layers and protective coating layers. This composite approach leverages the excellent high-frequency properties of LCP while integrating the conductive properties of copper and the protective functions of coating materials, achieving both high reliability and manufacturability
2Stability of the object's composition
If PI film is used as insulating substrate, then the soft board can be produced with standard materials, but moisture absorption is high and structural characteristics are poor
Solution Approach 1:
The patent changes the chemical composition parameters by substituting polyimide film with liquid crystal polymer material. This substitution reduces moisture absorption from 0.2-0.5% for PI to less than 0.1% for LCP, while simultaneously improving structural stability through LCP's inherent dimensional stability and low thermal expansion coefficient
3Productivity
If traditional multi-layer flexible circuit board is prepared, then the circuit board can be manufactured with conventional processes, but the process flow is complex and power consumption is high
Solution Approach 1:
The patent merges multiple manufacturing steps into an integrated coating process. By applying synthetic liquid films directly onto the substrate in a continuous coating operation followed by unified heating treatment, the patent combines what would traditionally be separate lamination, coating, and curing steps into a streamlined process, reducing both process complexity and power consumption
Solution Approach 2:
The patent performs preliminary preparation by applying the synthetic liquid film coating before final assembly and curing. This preliminary coating action ensures proper material distribution and adhesion preparation, allowing subsequent heating to efficiently complete the bonding process in one step rather than requiring multiple iterative adjustments
4Loss of energy
If conventional coating process is used, then the manufacturing process is simple, but the signal transmission loss at high frequency is high
Solution Approach 1:
The patent changes the material parameters of the coating layer by using synthetic liquid films with optimized dielectric properties. The coating materials are formulated to have low dielectric constants and loss factors, directly reducing signal transmission loss while maintaining a relatively simple application process through liquid film coating and heating
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach simplifies the manufacturing process, reduces production costs, and enhances signal transmission performance by using advanced materials that improve stability and reduce power consumption, enabling high-speed and low-loss transmission of high-frequency signals, specifically for 5G technology applications.
Implementation Method 1
delivering the copper foil coated with the synthetic liquid film into a tunnel oven, and successively passing the same through a plurality of sections of heating and roasting zones in the tunnel oven at a speed of 0.5-20 m/s for roasting in sections
Implementation Method 2
successively passing the same through a plurality of sections of heating and roasting zones in the tunnel oven
Implementation Method 3
delivering the single-sided board coated with the synthetic liquid high-frequency material layer to the tunnel oven, and successively passing the same through a plurality of sections of heating and roasting zones in the tunnel oven at a speed of 0.5-20 m/s for roasting in sections
Implementation Method 4
successively passing the same through a plurality of sections of heating and roasting zones in the tunnel oven
Data Source
AI summary
The present invention discloses a method for coating and forming a novel material layer structure of a high-frequency circuit board, comprising the steps of: (1) coating a synthetic liquid film on a copper foil; (2) delivering the same to a tunnel oven for roasting, and forming a cured film on the copper foil to obtain a single-sided board; (3) coating a layer of synthetic liquid high-frequency material on the cured film; and (4) delivering the same to the tunnel oven for roasting until the synthetic liquid high-frequency material layer becomes a semi-cured high-frequency material layer so as to obtain a novel material layer structure of a high-frequency circuit board. An article prepared by performing the above methods is also disclosed. The prepared novel material layer structure of the high-frequency circuit board has the performance of high-speed transmission of high-frequency signals, and can adapt to the current high-frequency and high-speed trend from wireless network to terminal applications, especially for new 5G technology products. It can be used as a circuit board preparation material to make a single-layer circuit board, a multi-layer flexible circuit board and a multi-layer soft-hard combined board, which brings great convenience to circuit board preparation and simplifies the process.