Understanding single-sided PCB and how it’s etched
As far as printed circuit technology is concerned, the most basic technology and start point of invention is single sided PCB. Single sided PCB is the most simple and basic PCB board. However, this does not prevent it from playing a major role in the industry. On one side of single-sided PCB are conducting wires while the other side features the components. Developed in early 1950’s, this type of PCB dominates the world market to date. Best suited for low-density designs, this cheap PCB contains only a single layer of conductive material.
Easily designed and quickly manufactured, single sided PCBs are most cost effective printed circuit boards in the industry. So how is this type of PCB manufactured? A thin layer of electrically insulating and thermally conductive dielectric is laminated with copper after which the top of the copper is soldermasked. There are many benefits of this type of PCB including:
- Cheap PCBe. lower cost especially when orders are of high volume
- Perfect for low-density designs
- Easily understood by most printed circuit board manufacturers
- Less chance of manufacturing problems
- Common and popular
Today, you’ll find single sided boards with surface finishes such as gold plating, organic surface protectant (OSP), tin, and immersion silver. You can use this type of PCB in complex devices even though it’s a relatively simple board. Some of the devices in which you can use this cheap PCB include:
- Vending machines
- Cameras
- Printers
- Calculators
- Solid state drives
- Coffee makers
- Power supplies
- LED lighting
- Surveillance
- Relays
- Packaging equipment
- Timing circuits
- Radio and stereo equipment
- Sensor products
Making single-sided PCBs is quite simple. First and foremost, you’ll need certain materials to produce a single sided board. The materials include:
- Single sided 1-ounce copper clad
- PCB drills
- Five-gallon plastic bucket full of water
- Muriatic acid
- Scrubbing pad
- Household hydrogen peroxide
- Drill tool
- Safety goggles
- Tin snips
- Good quality magazine pages
- Paper towel
- Laser printer
- Rubber gloves
- Plastic container in which the board will fit
- Lacquer thinner
- Iron
- Soft plastic brush
After you have all the aforementioned materials with you, use the following steps to etch single sided PCBs:
- Use a piece of paper from a high quality magazine to print the bottom side layer. Make sure that you don’t use the magazine cover for this purpose. Furthermore, you must use a laser printer and not an inkjet.
- In order to remove any oils, wash your hands. Once the pages are printed, keep handling to a minimum—avoid touching the printing with your fingers and keep pages as flat as possible.
- Carefully remove the copper clad from its packaging. If required, cut the copper clad into size with the help of a tin snip. Gently polish the surface with the scrubbing pad. Use a slightly damp paper towel to clean off the residual dust.
- For ironing, choose a sturdy, flat, heat-resistant, and hard surface. Set the iron on the hottest setting after emptying the water out of it.
- Place the copper side of the copper clad facing up and the blank side facing down. With the printing facing the copper, align printing onto copper clad board.
- Firmly press the magazine paper’s back with an iron. Let the board fully cool when you’re done ironing. Soak the board for five minutes by putting it in water. In order to leave only the print from your laser printer, excoriate the wet paper from the board.
- Clean the toner from copper board using paper towel and lacquer thinner if every trace isn’t adhered to the copper clad. Once you’ve done this, start over.
- Take a plastic container and add two cups hydrogen peroxide to it. In order to create the etching solution, gently pour the contents of the container in a cup of muriatic acid.
- In the plastic container, place the board with its copper side up. Gently wipe the board with a soft brush. All the exposed copper will dissolve in three to four minutes.
- Take the board out with your hands after wearing rubber gloves. In order to ensure that all the exposed copper is dissolved, inspect it. Rinse the board under water if it’s dissolved. Use a paper towel to dry the board.
- By diluting it in a five-gallon bucket of water, dispose of the etching solution.
- Remove any toner left on the top of the copper traces with the help of a paper towel and lacquer thinner.
- In order to prevent the copper from oxidizing, perform tinning. Because it centers the drill bit, tinning makes drilling easier.
- Using the drill tool and correct size PCB drills, drills all the holes for the components. Using a normal drill, drill large mounting holes.
- On a magazine paper, print out the top side silkscreen layer and then using the same processes as above, iron this onto the top side