NALUX NANO OPTICAL, INC.
65 E.State Street, Suit2000
Columbus, Ohio 43215
c/o Schneider Downs
"Lighting a path to the future with nano-optics."
Electron beam lithography is a very precise process for patterning resist which is a key step in the process of making the micro structures of micro optics. The way electron beam lithography works is that you start out with a wafer of glass (or metal) coated with a material called resist. There are many different types of resist and choosing the correct resist is critical to electron beam lithography. Once the wafer is coated with resiste, the next step in electron beam lithography is to expose the resist to the electron beam. The ion beam causes the resist to harden and the beam is programmed so that only certain areas of the wafer are hardened and even the depth of hardening is exposed. This allows electron beam lithography to create any arbitrary shape desired. Electron beam lithography can create lens shapes, blazed grating shapes, Fresnel lens shapes, light pipes, waveguides, diffractive optics, and a wide range of other shapes.
After the resist on the wafer is exposed in the electron beam lithography step, the next step is to put the wafer into a plasma etching chamber to etch away the remaining photoresist and the exposed wafer so that the structure required can be imparted to the glass wafer. As mentioned earlier, this combination of electron beam lithography and plasma etching is also used on metals and is often the method used to create the injection molds needed for Nalux's plastic injection molding operations.
Electron beam lithography has both advantages and disadvantages over other fabrication methods. It is an extremely accurate method, allowing very tight control down to sub micron dimensions. Electron beam lithography also offers a great deal of design freedom as it allows for the creation of just about any shape. The biggest negative in the electron beam lithography process is that it is a fairly slow process and takes a long time for creating the structures, typically between 2 and 4 hours per square millimeter.
So, like any process, electron beam lithography has it's strengths and weaknesses and is another tool that Nalux has to provide our customers with the optics they need. Give us a call and see how we can put electron beam lithography to work for you.