What is Plasma?

Plasmas – we have all seen them, but may not have realized it. Plasma has a visual appearance similar to that of aflame. Just like flames, plasmas are comprised of glowing gases, but combustion is not the primary cause for the appearance of emitted light.

Plasma forms when certain amounts of energy, like heat or more commonly some kind of electricity, passes through a gas. The excess energy changes the gas into the 4th state of matter, just as heat changes ice from the first state of matter, a solid, into the second state, a liquid. In the first three stages of matter, the excess energy increases the relative spacing between atoms or molecules comprising the matter.

 

Unique to the fourth state of matter, the excess energy liberates electrons from the atoms or molecules in the matter, leaving them charged or ionized. The collection of free electrons and ionized gas called a plasma makes for an incredibly diverse source of chemistry that is not normally available.

 

Stars are made almost solely from plasma, Since stars comprise ~99% of the known universe, plasma is actually the most abundant form of matter. Plasma can also be found here on Earth, both naturally and artificially. During electrical storms, plasma is formed due to the electrical charge stored in clouds rushing to the ground, in a process known as lightning. Using large amounts of electricity, a miniature lightning bolt can be made, commonly called electrical arcs. Arcs are used for a variety of purposes such as cutting or welding metals.

 

Both lightning and electrical arcs are very hot kinds of plasma. However, plasma does not have to be hot. The ordinary fluorescent light bulb, neon sign, or devices used to manufacture microelectronic chips are examples of plasma operating at significantly lower temperatures. These cold plasma devices usually contain gases maintained at very low pressures (near vacuum) so that the plasma forms evenly inside the device.

 

Cold plasma can be made at atmospheric pressure too. Saint Elmo’s fire, corona discharges, and dielectric barrier discharges are common examples. The chemistry created by these types of plasma devices has been in use for many years for the production of ozone and altering the properties of surfaces. The challenge with these previous types of plasma devices is to form the plasma evenly without requiring the use of a costly inert gas (such as helium or argon). If the plasma does not form evenly, then items exposed to the plasma are not uniformly treated or processed. Furthermore, the non-uniform plasma devices may damage delicate surfaces or not treat a gas stream as efficiently.

 

Advanced Plasma Products, Inc.’s plasma technology answers this challenge by creating the plasma uniformly, at atmospheric pressure, low temperatures (typically room temperature), and without the use of expensive inert gases, or even exotic electrodes. The patented OAUGDP plasma technology was the world’s first diffuse dielectric barrier discharge operating using air. All of these unique features combined with the diverse plasma generated chemistryenables Advanced Plasma Products to build superior atmospheric pressure plasma devices that operate significantly more efficiently for a fraction of the cost.