Someone interested in electronics may ask you: “How is a Printed Circuit Board (PCB) board made?” And you are likely to give a generic answer like ‘a PCB board is made by carving circuits into a flat panel of nonconductive material.’ That’s not entirely true.
What is the whole process of making PC boards like? PCBs are caused by being impregnated with unique chemicals through photolithography. The production of PCB boards includes making a negative image imposed on a photosensitive board.
And then, the board is exposed to light and washed off with chemicals, leaving the non-exposed areas in the material behind getting etched away. You might think that Printed Circuit Boards are just something that the types will make of toys you buy.
However, in the United States, PCBs are actually a very common thing and are used in most electronics and products you buy.
The PCB manufacturing process is complex and can seem quite scary to design engineers who are used to producing boards at home. However, there are plenty of options available to them if they need to move their task out of the house, so they needn’t worry—and they can concentrate on designing their circuit boards.
Even if you aren’t a manufacturing expert, you probably have purchased something in your life that has one of these items. Today, we will take a look at how a printed circuit board is made and manufactured.
What are Printed Circuit Boards (PCBs)?
Printed Circuit Boards (PCBs) are thin boards made of fiberglass, composite epoxy, or other laminate materials. The board is “printed” with conductive pathways to connect different components to function as a Printed Circuit Board. A Printed Circuit Board is used as the base in almost all electronic devices.
When we talk about Printed Circuit Boards (PCBs), we discuss a board that connects different components. It is made of a material that does not conduct electricity (insulator) on which weak metal layers have been deposited.
The metal layers connect some of the points where components are placed: these are called conductors or traces. They can also include pads to which leads from the elements can be soldered and features that mechanically support and position the components.
These features are made from the same conducting materials and are usually formed by etching away parts of the metal layers.
The PCB has several primary functions, including:
- Distribute power to various parts of the circuit.
- Provide a common ground for all courses.
- Provide a rigid platform for mounting circuit components.
- Allow environment protection to the board.
Hybrid PCBs
A hybrid PCB is a circuit board containing both surface mount and through-hole components. This is typically done if an SMT component must be connected to a through-hole element or vice versa. The result is a PCB with the density of a surface mount board but the ability to connect to components using either style.
The simplest way to design a hybrid PCB is to use the through-hole pads of the surface mount components as vias. This means that the board can be populated on either side, but it is not possible to connect two pins on the underside of the board.
You can also add through-hole pads and vias as required, but this will increase the cost slightly as you will have additional production steps (etching, drilling, and plating).
How Does a Printed Circuit Board Work?
A Printed Circuit Board is a nonconductive surface with copper tracks printed onto using chemical methods to etch the tracks onto it. These tracks allow electricity to flow through them and reach different circuit parts.
What Are The Different Types Of PCBs?
The two main types of PCBs are single-sided and double-sided boards. Single-sided boards have circuitry on one side only, whereas double-sided PCBs have circuitry on both sides of the board. A variation of these two types is multi-layer PCBs with multiple layers of circuitry etched on both sides of the board and connected via holes drilled through all the layers.
What are Printed Circuit Boards Made Of?
You probably know what printed circuit boards (PCBs) are! They are the base for electronic components that hold your circuits together. And you probably know how PCBs are made. If not, we’re here to help!
The bare PCB is made up of a thin layer of conductive material. Usually, copper is laminated onto a non-conductive substrate. The substrate can be fiberglass or another composite resin material.
This combination can be thought of in similar terms to plywood, with the copper being the wood grain and the substrate being the glue holding it all together. The copper layer can have any number of different designs on it, depending on the board’s intended use.
These designs can include traces (the copper “lines” that electricity flows through), pads (places for components to be soldered to the board), vias (small holes drilled through layers of a multi-layered board), and other features.
The design is printed onto a film, which gets transferred onto a photosensitive material on top of the copper layer. After exposure to light reveals where the copper should be etched away, it is developed like film in a darkroom and finally in an acid bath.
How many steps are involved in the formation of Printed Circuit Boards?
PCBs are formed in several different steps, depending on who the manufacturer is. This is because other companies may have their unique processes to create the PCBs.
The process of Printed Circuit Board fabrication involves the following steps to create a circuit board:
Designing the PCB
A skilled designer designs a PCB. The designer has to design the schematic of the circuit. The Gerber files are created based on the schematic. After designing the schematic, it has to be manufactured and assembled.
PCB Layout
After designing the schematic comes the PCB layout, which is done using various software like Altium Designer, Eagle, etc. It is imperative to lay out all of the components so that they don’t overlap each other, and at the same time, it has to be done as efficiently as possible.
The traces are laid out between these components so that they can be appropriately connected and avoid any short circuits. The vias are also laid out to have a proper connection between various parts placed on different layers of the PCB.
Creating the Gerber Files
The Gerber files are generated from this layout which can then be used for manufacturing purposes and then assembling these boards after manufacture.
The PCB CAM Process
Generating manufacturing data for your design is called “CAM output.” CAM stands for “Computer-Aided Manufacturing, ” which refers to any manufacturing process involving a computer in any part of the design or manufacturing cycle.
Your board design file is given to CAM Engineers who prepare it for production by generating Gerber files and NC Drill files (also known as Excellon files) from the CAD data.
These files contain information that the factory equipment requires to perform the actual manufacturing of your boards.
The Gerber format is an open 2D binary vector image file format used in the photoplotter and photoplotter industries. It was named after Joseph Gerber, who founded Gerber Scientific Instruments.
Ordering PCB Prototypes
Our professional engineers will process proofreading, finalize, check, and validate all CAM files to ensure that every order has been produced according to your request before entering the production phase. This step is necessary to avoid any delay or wrong delivery due to missing or incorrect data provided in your order.
PCB Assembly
In this step, the PCB is populated with components like resistors, capacitors, diodes, and ICs. This can be done in two ways: through-hole assembly and surface-mount technology (SMT).
Through-hole assembly requires drilling holes in the PCB and inserting the components into these holes. In contrast, SMT involves soldering components directly onto the PCB’s surface.
While through-hole assembly has been used since the 1960s, SMT has primarily replaced it due to its lower cost, more excellent reliability, and higher density of components.
Testing and Debugging
The testing phase allows you to determine whether your board functions following its specifications. At this stage, you should check if your PCB contains any design flaws or errors. As a result of this step, you may identify some errors that need to be corrected before mass production begins.
Bottom Line:
PCBs and printed circuit boards are the cornerstones of technology today. Multiple layers of materials are combined, and the traces are etched onto them, making them ready to take on all kinds of components.
Can you imagine what technology would be like without these? They’re a blessing and a curse, but we can’t live without them. But there’s so much more to learn about these boards…what are you waiting for?
The point of using PCB manufacturing services is that you don’t need to know how to design a circuit board; the experts will do it for you.
Please contact us with your thoughts on the PCBs manufacturing process. Do you have any questions? What have you been wondering about them? We will try to answer any questions we can. Also, if you could share this article with others, we would greatly appreciate it!