SPRITE: a modern approach to scanning probe contact resonance imaging

We describe a system for contact resonance tracking called scanning probe resonance image tracking electronics (SPRITE). SPRITE can image two contact resonance frequencies simultaneously and thus can be used to acquire quantitative mechanical properties without requiring tedious image registration or other forms of post-processing. SPRITE is up to ten times faster than its predecessor, and its use of digital frequency synthesis makes the frequency 100 times more precise. In addition, SPRITE can acquire quality factor images, which can be used to determine viscoelastic material properties. The resonant frequency of two eigenmodes and two corresponding quality factor images can be acquired simultaneously. These new features can enable accurate nanomechanical imaging of surfaces and devices. (paper)