High Quality 2 Layer PCB Manufacturing

2 Layer PCB Manufacturing Service:

A printed circuit board is an inevitable part of all electronic devices. A PCB can be single-layer, double-layer, and even multi-layer. Depending on the requirements of different devices, manufacturers use different types of PCBs.

In today’s article, we are going to talk about a two-layer PCB, its manufacturing process, the difference between a single-layer and two-layer PCB, and more. So if you want to know all about these, make sure to read them till the end.

What is a double-sided PCB?

A double-sided PCB refers to a copper-coated printed circuit board, also known as a two-layer PCB. Unlike a single-layer PCB, a two-layer PCB contains two coats of copper, one on the top and the other on the bottom. The dual-layer PCB also encompasses a unique insulating layer in the middle of two copper layers.

The two layers of a two-layer PCB need to connect with solid bridges, called vias. Being almost double in size compared to a single-sided circuit board, it efficiently covers the drawbacks of a one-sided PCB. As a result, a two-layer PCB gets used in more complicated devices, where a one-sided PCB cannot perform well.

Manufacturing Process of Double Layer PCB Production:

When it comes to the production process of a double-sided PCB, a two-layer PCB manufacturer has to follow a few different and more complex steps than producing a one-layered printed circuit board. Both the copper-coated circuit board layers should be the layout, and the circuits of the layers should connect with PTH. 

Let’s look at the most used manufacturing process of a two-layer PCB. 

• HASL-LF/ immersion gold surface production process: 

Cutting> drilling>1st copper plating>layout> 2nd copper plating> etching>solder mask>legend printing>immersion tin/ immersion gold>CNC routing>V cut>flying probe test>vacuum packaging

• Gold plating production process: 

Cutting> drilling> 1st copper plating> layout> 2nd copper plating>gold and nickel plating> etching> solder mask> legend printing>CNC routing> V cut> flying probe test>vacuum packaging

• Multi-layer HASL-LF/ immersion gold board production process: 

Cutting>inner layer> layer stack>drilling> 1st copper plating> 2nd copper plating> etching> solder mask> legend printing> immersion tin/ immersion gold> CNC routing> V cut> flying probe test> vacuum packaging

Pattern plating process: 

Copper clad board/ laminate>  cutting> punching and drilling benchmark> CNC drilling> inspection>deburring> electroless thin copper plating> electroplating thin copper> inspecting> brushing>filming>exposure and development>inspection and repairing>pattern plating (Cn + Sn/Pb)> film removal>etching>inspecting and board repairing>nickel-plated and gold-plated plugs>hot melt cleaning>electrical continuity detection>cleaning>solder mask>curing>legend>curing>shape processing>washing and drying>inspection>packaging>finished product.

Thin copper>thin copper electroplating>here, you can use an electroless thick copper layer instead of electroplating thin copper layers. 

SMOBC process: 

Another process of producing a duel-layer PCB is the SMOBC process. Double-sided copper laminate>electroplating process to etching>lead and tin removal>inspection> cleaning> solder mask>plug nickel playing and gold plating>plug sticking tape> got air leveling>cleaning> legend>outline> cleaning and drying>finished product inspection> packaging> finish product 

Additionally, you need to know about the plugging method, pore mechanism, debris plug hole, etc., before starting a two-layer PCB manufacturing process. 

What is the difference between single-sided PCB and two-layer PCB?

Single-sided and double-sided PCB differ in various metrics. For example, the first one encompasses only one copper layer, whereas a two-layer PCB is made with two copper layers connected with vias. 

• Additionally, if you notice the materials of a one-sided PCB on devices like a TV board, it comprises copper foil on one side. On the other hand, a two-layer PCB includes two copper traces on both sides, connected by conductive through holes.
• The solder joints on the one-sided PCB get concentrated on one side, and the SMD components get plopped on the other. But, paradoxically, in a double-sided PCB, the SMD components can get attached on both sides. Similarly, a two-layer PCB manufacturer can use both sides as a layout.
• The production process of one-sided PCB involves CAD or CAM CCL cutting, drilling, positioning, solder mask, OSP, etc. But, a two-layer PCB gets produced using processes like AD or CAM CCL cutting, NC drilling, hot air leveling, OSP, etc.

How do you make two layer PCB and precautions:

For making a two-layer PCB, you have to take the help of the reflow process two reflows for two layers. Firstly, make sure to place the delicate small parts on the reflow oven. Now, these tiny components will not fall off through the reflow oven as they will get placed immediately on the bottom of the board. 

Secondly, make sure the parts on the first side are going through the reflow oven twice. You must place the more significant components on the second side. Furthermore, parts with lower heat-resistant power, PIH/PIP, LGA, and BGA components must be placed on the same side. 

Soldering method of double-sided circuit board:

To assure the trustworthiness and conductivity of a two layer PCB, the PTH must get soldered with a wire. For that, you need devices that need reshaping, the power of iron (25-40 W), and lots of patience. 

The soldering method of a double-sided PCB follows: 

1. Observation
2. Dismantling 
3. Cleaning 
4. Layout
5. Soldering 
6. Inspection 
7. Power-on test

Frequently Asked Questions:

• What is a two-layer PCB? 

Two layer PCB is a copper-coated printed circuit board. A 2 layer PCB contains two coats of copper, one on the top and the other on the bottom, along with an insulating layer located amidst two copper layers. 

• Name some of the manufacturing processes of a two-layer PCB. 

Some two layer PCB manufacturing processes are- HASL-LF/ immersion gold surface production process, the Gold plating production process, the Multi-layer HASL-LF/ immersion gold board production process, multi-layer plate gold plate production process, etc. 

Conclusion:

These were all about two layer PCB and its manufacturing process. Now, when you have collected enough information about a two layer PCB, hopefully, you will not face any problems in the future. However, reach out to a professional for any further requirements related to 2 layer PCB.

Also read:-

• Difference Between 2 layer pcb vs 4 Layer pcb
• PCB insulation and its importance between layers