Double-sided black oil spray solder PCB
Double-sided PCB, also known as double-sided printed circuit board,
is a printed circuit board (PCB) with two-sided circuit
connections. In this kind of PCB, the electronic components and
circuit layout can be arranged on both sides of the PCB
respectively, and the electrical connection of the circuits on both
sides is achieved through vias (Vias). This structure greatly
increases the functional density of the circuit board, allowing it
to implement more circuit connections in a relatively small area.
Advantages of Double-sided PCB:
- Increase the wiring space
- Improve the circuit functional density
- The cost is relatively low
- Good electrical performance
- Adapt to high integration requirements
Main Features
1.Surface Finish
• Hot Air Solder Leveling (HASL) process
• Tin-lead alloy coating for enhanced solderability and reliability
Matte surface appearance
2.Solder Mask
• Black solder mask ink
• High contrast for better visual inspection
• Provides excellent protection for copper traces
• Cost-effectiveness
3.Economical manufacturing process
• Suitable for high-volume production
• Lower material and processing costs compared to other finishes
4.Applications
• Consumer electronics (e.g., smart home devices)
Industrial instruments
• Automotive electronics
• General-purpose PCB applications
5.Limitations
• Poor surface planarity
• Not recommended for fine-pitch components
• Lead-based process requires RoHS compliance
• Lead-free options available but at higher cost
Manufacturing process:
1.The base material is cut to the required size. Then, drilling is
performed for inner and outer layers. The dry film process involves
pre-treatment, film lamination, exposure, and development.
Lamination includes black oxidation treatment, micro-etching,
stack-up, and pressing. Copper reduction is used to thin down
copper layers, followed by electroplating which includes horizontal
electroplating and tin-lead electroplating.
2.Hole plugging involves printing, pre-baking, and post-baking.
Solder mask application includes green solder mask printing,
exposure, development, and post-curing. Gold plating is performed
for nickel-gold plating on gold fingers and immersion gold. HASL is
used to apply solder coating through hot air leveling process.
3.Profiling involves CNC milling and mold punching. Electrical
testing includes electrical testing and AOI (Automated Optical
Inspection). Finally, the process ends with final inspection,
visual inspection, cleaning, and packaging.
