Technical
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
Why choose Shenzhen SMT processing factory?
How long does it take to calculate the quotation for PCBA manufacturing?
Introduction of PCB design clearance requirements
Explanation of BOM, DIP, SMT, SMD
Introduction of the process of PCBA prototype
How to prevent pseudo soldering or cold soldering defects in PCBA manufacturing?
Factors that affect the Price of FPCB
What information is required for SMT processing at PCBA factory?
Skills of using 0ohm resistor in PCB design
How to select a PCBA manufacturer
SMT processing solder joint quality inspection
Characteristics difference between immersion gold PCB and gold plating PCB
Common malfunctions of Circuit Board Caused by Moisture
A Few Rules about PCB Panelization
Compare of multi-layer PCB with single/double layer PCB
Why do we need to introduce so many subdivided GND
Difference between immersion gold boards and gold plating boards
Aluminum PCB structure
Classification of different GND in circuit
Why PCB baking is necessary during manufacturing process
The handle and precautions of OSP board in SMT process
How to choose capacitors for filter decoupling
How to choose filter capacitor for switching power supply
5 database need for SMT process
Function of three-terminal capacitor
Introduction of PCB OSP surface treatment
Method of inspecting the quality of SMT by step
How to find the short point between VCC and GND
Difference between 850nm and 940nm infrared LED
Component layout of PCB SMT DFM
Pad shape influence on the strength and reliability of the soldering joints
The difference between high temperature solder paste and low temperature solder paste
Introduction to manual welding processing
Manual visual inspection in PCBA processing
Characteristics of the conformal coating process
Difference between hardware engineers and software engineers
PCBA processing operation rules
China PCB upstream materials has continued to soar
Difference between serial buses and parallel buses
The key points of quality control in PCBA processing
Common causes of solder beading during SMT process
Analysis of the advantages and disadvantages of HASL PCB surface
Requirements for layout of components during SMT assembly
Selection of electronic components and CCL for PCBA
Performance and appearance quality inspection of components.
Quality and Reliability of SMT Chip Processing and Production
Coupling and decoupling function of capacitor
Two methods to connect digital ground and analog ground
Common sense in SMT process

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.