Biomedical Engineering Reference
In-Depth Information
derivatives) nanolines as small as 58 nm in width were obtained
and the line width was controlled as a function of the writing speed
and writing potential [89]. The electrochemical nanolithography
process is shown in Fig. 1.3. Conductive AFM probes and gold-
coated silicon nitride (SiN
4
) are used as working electrode. Silver
wire and platinum wire were used as reference electrode and
counter electrode, respectively. Higher writing potential and
slower writing speed produce wider conducting polymer nanolines
due to enhanced propagation. The great benefit of this method
lies in no specific restriction in the choice of substrates and the
ease of controlling feature size, which is expected to facilitate to
fabrication of all plastic nanoelectronic devices.
Figure 1.3
Electrochemical nanolithography [89]. Reproduced by kind
permission from the publisher.
Application of an AFM tip as a “nib” to directly deliver organic
molecules onto suitable substrate surfaces, such as Au, is referred to
as “dippen” nanolithography (DPN) method [103-105]. When AFM
is used in air to image a surface, the narrow gap between the tip
and surface behaves as a tiny capillary that condenses water from
the air. This tiny water meniscus is actually an important factor that
has limited the resolution of AFM in air. “Dip-pen” AFM lithography
uses the water meniscus to transport organic molecules from tip to
 
Search WWH ::




Custom Search