There are a number of AFM techniques sensitive to local mechanical properties of a sample. However, it is still challenging to distinguish between the different properties of materials like stiffness, hardness, adhesion, and viscoelasticity on these compositional maps.

The pioneering approach utilizes a probe with a T-shaped cantilever carrying a tip on one of its "wings". The offset of the tip from the cantilever longitudinal axis provides a very sensitive torsional response of the probe when the tip intermittently strikes a sample. A large number of harmonics are generated in the tip-sample contact that can be detected by broadband controllers.

Instead of imaging of any of detected harmonics, one can perform a conversion of harmonics data into time domain for reconstruction of tip-sample force curves practically in each oscillatory cycle of tip-sample interaction (Fig.1). Therefore, one can obtain topography information, phase image and map of any properties derived from the force curves (elastic modulus, adhesion, etc) in a single scan (Fig.2). Such a way provides unique extension of nanoindentation in low-force (10 pN), high-resolution (1 nm) and high-speed (10 sec) domains.

Most samples that can be imaged in tapping mode in air can be investigated with TL300 probe. TL180 is for ultra high resolution mechanical measurements. This probe can perform sensitive mechanical measurements with peak tipsample forces less than 1 Nano Newtons as well as reliable and ultra-low force topographical imaging.

The nanoTWIST probe is a T-shaped cantilever having a tip on one of its arms. The positioning of the tip on one of the arms of the probe enhances its torsional motion when the tip interacts with the sample in the contact or oscillatory modes.