|
 |
|
|
|
Nanoscale Fabrication
|
|
Most of the nano-scale fabrication at Almaden is based on patterning with
electron beam lithography, using a Leica/Vistec VB6
electron beam lithography tool. In general, we use this tool and a host of subtractive and deposition processes to fabricate
prototype devices and structures. Although this approach is very versatile and has very high resolution, it is intrinsically
a serial writing process, and therefore relatively slow. So we are also investigating alternative nano-fabrication techniques,
based on
nano imprint lithography, self-assembly, and
optical interference lithography. In nano imprint lithography we use
electron beam lithography to make a topographically patterned "master" that can be used to imprint patterns onto many samples
in a single, rapid, imprinting step. In the case of self assembly, we are studying systems such as block co-polymers that
assemble spontaneously into nano-patterns. Here the challenge is to direct the assembly to get the desired patterns with the
required placement. Finally, we are using optical interference between colliding laser beams to directly write grating
structures with very high line densities, allowing us to test a range of new resist chemistries and opening up a range of
fabrication possibilities.
Figure 1. VB6 electron beam lithography machine.
|
|
|
|
|
|
