Biomedical Engineering Reference
In-Depth Information
Table 4.1. Properties of some commonly used substrates for AFM.
Material
Notes
y
Preparation
Roughness
Common samples
<
˚
(atomically flat)
Mica
cleaving
All, especially single molecules [319, 320] Cleaved material, so very stable in
storage. Hydrophilic [294, 305]
<
˚
(atomically flat)
HOPG
cleaving
All, especially single molecules [295]
Cleaved material, so very stable in
storage. Conductive. Hydrophobic [321]
<
˚
to a few nm [322] Lithography, electronic applications
None
*
or only oxide
removal
Silicon
Often the best choice for conducting
applications [251, 256, 323]
None
*
Quartz or Glass
slides
1-10 nm
Larger samples or films,
commonly used for cells [302]
Not especially flat but easy to work
with and cheap [324]
<
˚
Gold
Flame annealing or
to a few nm
Chemically modified surfaces
Easy to chemically modify; large
atomically flat terraces [325-327]
<
˚
template stripping
to a few nm
Chemically modified surfaces
Easy to chemically modify; like
cleaved materials highly stable in
storage [328-330]
*
Usually only cleaning is required.
y
Use of each of these substrates has been described many times; representative references are given here.
