nGauge AFM – Topographical and Phase images

The nGauge AFM is a ground-breaking instrument in the field of microscopy and surface characterisation, different to other prominent AFM systems in that there is no time consuming laser alignment. In addition to this, topographical images can be obtained within one minute, with only 3 clicks of a mouse. From the automatic frequency sweep to the approach features, ICSPI make it easy for the user to collect a range of information. The MEMS chip allows for a benchtop solution to AFM with no need for bulky chambers or isolation tables, covering up to 99% of AFM applications, despite its compact structure.

Topographical images are essential in establishing a deeper understanding of the morphology of a sample. These are formed by a probe tip running along the surface of a material, to gain a 3-D representation of the surface topography.

In addition to this, phase images can be obtained from a scan when the probe tip is in ‘tapping mode’. This mode is when the cantilever oscillates across the material surface without coming into contact with the sample, this can highlight different mechanical properties within a composition. Both topographical and phase images are generated simultaneously on the nGauge AFM.¬†

Surface topography can be a useful feature for a range of applications or purposes, such as: quality control, defect analysis as well as surface finish. These images can also have ‘hidden’ information about the sample that can be highlighted when comparing a topographical image with a phase image. This becomes more apparent when scanning samples such as composites or polymers.

Phase images can be used to obtain a deeper understanding of the matrix within a sample, these images can be used to identify areas with different mechanical properties such as adhesive, viscoelastic or frictional. Due to this, phase images can be used to distinguish regions where a sample has been contaminated, a range of polymers in copolymers, grain boundaries as well as a range of other characteristics.

Below is a silica-polymer composite. The example images are topographical (left) and phase (right).

On the left, there are only a few distinguishable features, in this instance, the bright particles are the tallest features that can be seen, with the rest of the morphology being relatively uniform. However, when looking at the right image, it becomes clear that you can distinguish the silica from the polymer matrix because of the colour; the variation in colour is due to the different mechanical properties of the components in the composite.

For more information on phase images or the nGauge AFM, contact us or visit the ICSPI website.

Contact us if you’d like to book a demo, find out more information or organise sample testing with ICSPI’s nGauge AFM.