Quantitative Mechanical Measur

Introduction
Feature miniaturization, especially
in the electronics industry, demands
knowledge of mechanical properties on
the scale of nanometers. Instrumented
indentation facilitates such testing,
because the area of the contact
impression does not have to be
measured visually, but can be inferred
solely from the relationship between
applied force and consequential
penetration of the indenter into the
testing surface [1]. Instrumented
indentation has been used since
the 1980’s to make measurements
at the sub-micron scale, but recent
developments allow quantitative
determination of mechanical properties
using indents of just a few nanometers
deep. This article addresses special
considerations for such testing, and
reports results for seven different
materials tested with the DCM II. 

The DCM II, shown in Figure 1, is an
optional high-resolution actuating
transducer for the Agilent G200
Nano Indenter.  The DCM II may be
used in addition to or instead of the
standard indentation head.  If both
heads are included on a single system,
transition from one head to the
other is entirely software controlled;
the user doesn’t have to make any
adjustments to hardware, controllers, or
calibrations.  The range and resolution
in displacement (travel) are 70µm and
0.0002nm, respectively.  The range
and resolution in force are 30mN
and 3nN, respectively.  Because the
DCM II has a resonant frequency of
about 120Hz, measurements of force
and displacement are insensitive to
environmental noise which occurs at
lower frequencies. The DCM II can be
used in combination with a variety of
indenter tips including Berkovich,
cube-corner, and sphero-conical.
Changing from one tip to another
takes just a few minutes.