A coupled spring system is applied to dynamic force spectroscopy measurements. A microcantilever-mounted probe acts as a first spring, and a supported micromachined membrane acts as a second spring. The coupled spring system provides a system spring constant that is lower than either spring individually. By probing different regions of the membrane, the spring constant of the system can be varied.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
 The United States Government has rights in this invention pursuant to Contract No. DE-AC05-00OR22725 between the United States Department of Energy and UT-Battelle, LLC.