Like any other printed circuit board, rigid PCBs are manufactured by following a particular procedure. Here, we will discuss each step in the entire manufacturing process.
Material Preparation: The process begins with the bare production boards. These are cleaned using chemicals, before they are sent for the application of photo resist film. Generally an automated conveyor line is used to transport multiple pieces. The intention of this is to ensure that the boards do not get damaged in any way. It is also performed to ensure a fast manufacturing process.
Exposure of Circuit Pattern: Once the panels have undergone the application of the photo resist, the board is then laid with the various circuit artwork patterns. This process is performed by exposing the board to UV light, to help transfer the circuit images onto the production panels. This process can be performed to single or both sides of the board.
Etching: With the circuit pattern having been transferred onto the board, the next step is etching. This is where circuit patterns are chemically etched onto the board. This process is performed by specialized handling equipment and automated chemical etching machines.
Drilling: Once the circuit pattern has been etched onto the board, the next step is to drill the holes for the circuit patterns. It is important that the drilled holes are of a particular size, adhering to exact specifications. Generally, PCB manufacturers utilize two types of equipment to perform this process. Specialized drilling machines with several drill mechanisms can be used to create holes in multiple boards. They also utilize laser drills to get clean, precise holes in a very short period of time.
Copper Plating: With the drilling complete, the board can now undergo the copper plating process. This is where additional copper is applied onto the circuit board to create layer-to-layer interconnections. For this purpose, manufacturers utilize automated copper plating systems. They apply the copper onto the plated through holes.
Coverlay Application: For protection and performance purposes, the PCB is covered with a coverlay laminate. Polyimide coverlays are one of the popular options for rigid PCBs. This process comprises aligning and tacking the laminates into place. This process can be performed by hand, or with automated machines.
Coverlay Lamination: With the coverlay aligned and tacked, it now needs to be laminated to the board. The boards are placed in specialized lamination machines. These machines apply a combination of vacuum, heat, and pressure. This ensures that the laminated is properly stuck to the board.
Stiffener Application: This is an optional step performed by PCB manufacturers. However, most designs do use this component. Stiffeners are supportive components that are used to prevent the lamination to prevent it from moving, or becoming loose. Generally, stiffeners are applied prior to the coverlay lamination process. They are adhered to the board using heat, vacuum, or pressure.
Mounting: Once all the components and lamination has been completed, the PCB needs to be assembled. Generally, Plated Through Hole (PTH) mounting technology is used for rigid PCBs. In this process, the leads of the components are passed through the drilled holes. The leads are then soldered to pads on the opposite side of the circuit board.
Testing: For a PCB to be considered fit for an application, it has to meet the requirements of the following testing procedures – electrical, AOI, and functional. Electrical testing involves using flying probe test machines to ensure that all the electrical connections such as shorts, opens, and capacitance, of the PCB are working properly. Automated Optical Inspection (AOI) involves using an optical imaging system to check the PCB for faults, and soldering and assembly defects. Functional testing is the final step. The functional test machine verify that the PCB’s hardware is free of any defects.
These are the basic steps used in the production of a rigid PCBs. These PCBs can be constructed with single, double, and multiple layers. For a PCB to meet all requirements of the application, it is important to provide detailed information about the application to the PCB manufacturer. This will allow him to design the PCB according to your needs.
PCB Manufacturing Capabilities
Number of Layers
14 – 40
FR4 FR406 IS410 Kapton Shin-Etsu – Epoxy Adhesive System Rogers – Epoxy Adhesive System Dupont FR – FR Acrylic Adhesive System Dupont LF -LF Acrylic Adhesive System Adhesiveless Base Materials