Specific Process Knowledge/Lithography/EBeamLithography: Difference between revisions
| Line 377: | Line 377: | ||
= Charging of non-conductive substrates= | = Charging of non-conductive substrates= | ||
Exposure on a non-conducting substrate the accumulation of charges in the substrates will however destroy the e-beam patterning. To avoid this, a charge dissipating layer is added on top of the e-beam resist; this will provide a conducting layer for the electrons to escape, while high-energy electrons will pass through the layer to expose the resist. | |||
At DTU Nanolab, we recommend to use a thin (20 nm) layer of thermally evaporated [[Specific Process Knowledge/Thin film deposition/Deposition of Aluminium|aluminum]] on top of the e-beam resist. Preferably, the thickness of Al and the e-beam dose should be optimised to the features you wish to e-beam pattern [http://nedds.co.uk/wp-content/uploads/2013/06/Greer-et-al-DRM-29-July-2012.pdf]. A good starting point is 20 nm Al; from here dose and development can be optimised to reach the resolution and feature size required. The aluminum layer is easily removed with MIF726 after exposure and prior to development of the e-beam resist. | |||
The process flow for a standard e-beam exposure on CSAR with Al on top can be found here [[media:Process Flow CSAR with Al.docx|Process Flow CSAR with Al]]. | |||
If your process can not utilize a aluminum discharge layer, Espacer might be another possibility to pursue. Espacer is a chemical that works as a discharging layer; it is spun onto the wafer on top of the resist and easily rinsed off the wafer after e-beam exposure. Visit this page for more information: [[Specific_Process_Knowledge/Lithography/Espacer|Espacer]] | |||
= Literature on E-beam Lithography = | = Literature on E-beam Lithography = | ||