What is Air Ionization and How Does it Work?
What is an ion?
How Do Air Ionizers Create Ions?
There are two methods air ionizers work. The first is alpha ionization, which uses a nuclear source such as polonium 210. The polonium 210 particles collide with the air, transferring electrons, causing the neutral air molecules to become negative ions. Since the polonium loses electrons, it becomes a positive ion. Alpha ionizers are beneficial because they create an equal number of positive and negative ions.
The second method is called corona ionization, which uses an electrical current to create bipolar ionized air. The ionizer applies a high-voltage electrical current composed of a flow of negatively charged electrons, to a metal prong or needle. Electrostatic repulsion causes the electrons to detach from the prong or needle, attaching themselves to the molecules or nitrogen and oxygen in the air, forming negative ions, which are attracted to the static charge in the work environment thus neutralizing it. These ions also attract certain types of molecules in the work environment like dust and other air particulates. These particulates cluster around the ion, weighing it down and forcing it to fall to the ground, cleaning the air.
Corona ionization can further be divided into AC and DC. AC or alternating current ionization uses one emitter to produce both positive and negative ions. This type of ionization is mainly used to protect components during assembly. DC or direct current uses separate positive and negative power supplies that run simultaneously to create bipolar ions. DC ionizers are more efficient at producing ions and use lower operating currents, making them a better fit for cleanroom applications.
Use of Ionizers for Non-Essential Insulators
All non-essential insulators such as coffee cups, food wrappers, and personal items shall be removed from the EPA. The ESD program shall include a plan for handling process-required insulators in order to mitigate field-induced CDM damage. If the field measured on the process required insulator is greater than 2000 volts/inch and the process required insulator is less than 30 cm (12″) from the ESDS item, steps shall be taken to either:
- Separate the required insulator from the ESDS item by a distance of greater than 30 cm (12″)
- Use ionization or other charge mitigating techniques to neutralize the charge.
How Are Air Ionizers Used?
The XC2 has shown to be specifically useful for larger areas, offering under 12 second discharge times at 6 foot workbench distance from the face of the blower. The weight-saving design allows the Aerostat XC2 to be mounted above the work surface, which is especially effective for flat panel display module assembly.
Overhead Cleanroom Ionizers
The Model 5810i is certified for use in ISO Class 4 cleanrooms (Fed. Std. 209(e) Class 10). The ionizer can operate with external sensors to maintain precise balance (better than ±1V) by altering ion output and adapting to environment changes. With the reliability of steady-state DC, the established method for eliminating the effects of ESD and ESD-induced electromagnetic interference (EMI) in high-tech facilities, the Model 5810i delivers maximum ion output where and when you need it.
Cleanroom Benchtop Ionizers
Simco-Ion’s ISO Class 5 Self-balancing blower with FMS Interface is an efficient and small blower for controlling static discharge in hard-to-reach areas.