Electrostatic discharge or ESD for short, is when two electrically charged materials come into contact with each other creating a sudden discharge of static electricity.
The main type of ESD is caused by the Tribocharging effect which is when two surfaces touch or rub together creating static electricity. One surface gains negative electrons whereas the other surface loses them and becomes positively charged.
Although ESD can be cause also by Electrostatic Induction.
Once this new positively charged material meets ESD sensitive semiconductors, the charge from the positively charged material quickly “jumps” onto the material (usually a component) which can lead to component damage/failure.
When a material experiences the effects of Electrostatic Discharge (ESD) there are two main types of possible damage: Catastrophic failure and latent defects. Latent defects is when the ESD shock will not destroy the component but will actually damage/ degrade it so that it is still operational but may fail during its operational lifespan. This may go unnoticed which is why reducing the chances of ESD damage is so important.
Catastrophic failure is when the ESD shock completely “kills” the component. The high static voltage giving high levels of current can cause the component to simply burn out. Catastrophic failures can form fusing of internal wires or oxide breakdown failure.
We can protect our components from ESD by using anti-static flooring in our workshops and grounding straps when handling our PCB’s or components. Common anti-static wristband you will find in a lab or workshop environment to help prevent Electrostatic Discharge.
Electrostatic Discharge is one of the most common culprits for damaged electronic components, I have personally experienced this while using ESD sensitive filters during a soldering task on my university work placement. The filter was so susceptible to ESD damage we couldn’t walk across the carpet in the office without damaging it, the filters could only be handled in the lab on the anti-static flooring this was the only way we could be sure the parts would not be damaged.
You now know a little about Electrostatic Discharge and why ESD can be very damaging depending on the components you’re working with. Just remember to wear your anti static wristbands/footwear.