Technical
What are the advantages and applications of flexible microcircuits?
FPC Reinforcement Types
Criteria for Classification of electronic Component Classes
Four softwares suitable for beginners to draw PCB circuit boards
What information is needed for SMT processing?
What are the advantages of small and medium batch SMT processing?
PCB related knowledge- The purpose of each layer of the PCB
How to do heat resistance testing for PCB board
Detailed explanation of rigid-flex board and IC carrier board
PCBA prototype procedure
Defects which can be detected by the SPI
What are the spacing requirements for designing PCB circuit boards?
What are the classification and advantages of PCB metal substrates?
Difference between the processing technology of 1Layer AL PCB and 2Layer AL PCB
Introduction of FPC Cable and its usage
advantages of Shenzhen SMT assembly factory
inspection items before PCB ordering
usages of ceramic substrates
main applications of PCB boards
Cost-effective PCB product services
How to check short circuit of a circuit board during manual soldering
Identify the polarity of electronic components during PCBA processing
Means Which Can Prevent Component Shifting in SMT Processing
Skills of PCB prototype manual soldering
Reasons for the shift of Components in the SMT Process
Seven Types of PCB Probes
What Should Be Paid Attention to in Layout of High-frequency PCB
Precautions for PCB CCL Selection
Advantages of LED Plant growth light
Advantages of using LED grow lights to grow industrial hemp
Detailed explanation of PCB manufacturing process and precautions
Detailed explanation of PCB manufacturing process and precautions
How to draw multilayer PCB on Altium Designer
Three basic elements of interference and how to suppression them.
Decrease interference between digital circuit and analog circuit
SMT Component Placement Process Of Parts : Manual Placement
SMT factory incoming PCB material inspection
Basic concepts commonly used in PCB design
Ideas and principles of High speed PCB layout
Component layout rules and safety distance considerations
SMT assembly process quality specification
5 points in PCB layout
Professional interpretation of SMT
Advantages and disadvantages of different PCB surface treatment
Special process in PCB prototype
Why the via hole become open after component assembly
Keep the cost of the PCB as low as possible
what are the causes of PCB board heating radiation problem
Pad size and via diameter dimensions consideration in PCB prototyping
How to Judge the Acceptance of PCB Quality
Which Color Circuit Board Sells the Most Expensive
Method to Solve the Noise Interference of Power Supply on High-frequency PCB Board
Disassembly Skills of Chip Components on PCB
What Factors Should Be Considered in the Selection of High-frequency PCB CCL
How to Place Special Components during PCB Layout
What Are the Functions of Capacitors in Circuits?
Testing Techniques for Common Electronics Components
What to do if There is a Short Circuit on the PCB
Desoldering Principles and knowhow during PCBA Processing
Black Oxidation of the Inner Layer of the Multilayer PCB
How to Ensure the High-performance Design of PCB
What Is the Printing Process of SMT Solder Paste?
PCB without fiducial mark, Is There Any Way to do SMT for It
What Are the Benefits of Reserving Break-up Tab for PCB Production
How Does SMT Affect PCB Production Time and Speed It Up
Classification of PCBs from three aspects
Common Problems and Solutions for Dry Film pasting during PCB Manufacturing process
Several Elements to Inspect after PCB Design
What is a halogen-free circuit board?
What Do Capacitive Coupling and Decoupling Mean?
What Are the Differences Between PCB Paste Mask and Solder Mask?
How PCBA Is Packaged and Shipped
How long can PCBA finished products be stored?
What Are the Differences and Relations Between PCB, PCBA, and SMT?
PCB Baking Specifications
PCB "Solder Mask Tenting" and "Solder Mask Opening"
Five reasons for PCB deformation and six solutions
Importance of first article inspection of PCBA board
Temperature zone standard for SMT reflow soldering
Small and medium volume PCB manufacturers in China
The main reason for PCBA cleaning
For power filter, the more capacitors, the better?
What does PCBA programming mean?
Content of PCB incoming testing
What conditions must be met for PCB circuit board soldering?
What is Blind via and Buried via
PCBA Manufacturers Temperature and Humidity Sensitive Components Management

What is a halogen-free circuit board?

What is a halogen-free circuit board? What is the difference between halogen-free PCB and usual made PCB?

Are there environment-friendly circuit boards? What is going on with the halogen-free PCB, which is widely used abroad? How is the halogen-free board different from the board we usually make?

What is halogen?
In the periodic table of chemical elements, the elements of group ⅦA of the periodic system refer to halogen elements, including fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At).

What is a halogen-free circuit board?
According to the JPCA-ES-01-2003 standard, copper clad laminates with chlorine (Cl) and bromine (Br) elements less than 0.09% Wt (weight ratio) are defined as halogen-free copper clad laminates. (JPCA is the abbreviation of Japan Electronic Circuit Industries Association.)

What is the difference between the halogen-free circuit board and the board we usually make?
At present, the flame retardant CCL substrates FR4, CEM-1, CEM-3, etc. used in the circuit board market are mostly brominated epoxy resins.

Relevant institutions have done research on epoxy resin substrates: when halogen-containing flame-retardant substrates are discarded and burned, they will release harmful substances such as dioxins. This substance has an unpleasant smell, is highly toxic, and can cause cancer. Once inhaled, it cannot be discharged, which will cause huge harm to the human body.

The halogen-free board realizes the environmental protection and non-toxicity of the PCB by replacing or reducing these harmful elements.

At present, most of the halogen-free materials are mainly phosphorus-based and phosphorus-nitrogen-based. What's interesting is that high polymer resins containing phosphorus and nitrogen compounds will produce non-combustible gas when burned. This gas can isolate the burning surface of the resin from the air and achieve the purpose of flame retarding.

What are the advantages of halogen-free PCB?
In addition to being environmental-friendly, halogen-free PCB also has good heat dissipation reliability and are more suitable for the high-temperature processes required by lead-free circuits.

Since the halogen-free PCB uses P or N to replace the halogen atoms, the polarity of the molecular bond segment of the epoxy resin is reduced to a certain extent, thereby improving the insulation resistance and anti-breakdown ability.

Things often have two sides. The advantages of halogen-free boards are at the cost of increasing complexity, not only in the PCB manufacturing process but also in the PCB design. There are differences between halogen-free PCB and conventional PCB, such as drilling. 
The P and N series functional groups used in the halogen-free board increase the molecular weight and enhance the rigidity of the molecular bond, resulting in increased rigidity of the material. At the same time, the TG point of the halogen-free material is generally higher, so the effect of using the ordinary FR-4 drilling parameters to drill is not satisfactory. When drilling halogen-free boards, some adjustments should be made under normal drilling conditions.