ABSTRACT
The atomic force microscope (AFM) was invented shortly after
the invention of the scanning tunneling microscope [1, 2] with
the specific purpose of providing high-resolution surface images
of nonconductive samples [3]. The initial demonstration of this
instrument showing a lateral resolution of 30 A˚ and a vertical reso-
lution of less than 1 A˚ from an insulating mineral surface generated
great excitement not only from material scientists but also from
biologists, as most biological structures are insulators in nature.
This excitement has not abated to this day, and improvements in
performance are continuously being introduced [4-6].
