65 E.State Street, Suit2000
Columbus, Ohio 43215
c/o Schneider Downs
Attention:Dennis R.Mowrey


"Lighting a path to the future with nano-optics."

Plasma Etching

Plasma etching is a key process in the creation of micro optics.  In this process, a high speed stream of atoms is fired in pulses at a sample with the plasma source being either charged or neutral.  As the plasma etching process continues and the surface of the sample is etched away, chemical reactions between the elements of the sample and the chemical constituents of the stream create volatile compounds.  Additionally, the atoms actually embed themselves into the surface of the sample and change the physical properties of the sample.  

Plasma etching ionizes many different source gases by radio frequency excitation.  There are many different variables that must be tightly controlled in order to get the results you want.  The radio frequency can be varied.  The gases used in the plasma etching process can and must be varied because different materials need different gas chemistries if they are to be successfully etched.  When plasma etching materials such as fused silica and other glasses which are very stable materials, extremely reactive and aggressive gases (bromine, fluorine, chlorine, etc.) must be used.  Additionally, the pressure inside the chamber will also affect the time and the completeness of the plasma etching process.  

Plasma etching is used for making micro optics but it also used for making a wide variety of other products such as printed circuit boards, connectors, and medical devices.  When making micro optics, the plasma etching process first must have a wafer of glass or other material with a photoresist patterned on top where the photoresist protects portions of the glass wafer while other portions are left exposed.  The plasma etching process then etches away the glass in order to create the surface structure required for the desired optical performance.  

A special type of plasma etching is the Reactive Ion Etching (RIE) process.  RIE is a process which is extremely directional and anisotropic making it a very useful process for creating micro optics.  

Plasma etching can also make all kinds of structures such as blazed gratings, binary structures, Fresnel zones, free form structures. torroids, and a host of other structures.  

Nalux has the equipment and the knowledge of plasma etching to very accurately fabricate micro optics.  Give us a call and find out what solutions we have for you.