Scanning Probe Microscope
The scanning probe microscope (SPM) XE-100 by PSIA is a second generation SPM, i.e. consisting of two physically independent scanners. The first one, the X-Y scanner, which moves the sample, covers a 100 x 100 µm2 area (10 x 10 µm2 in low voltage mode) with a resolution of < 0.15 nm (< 0.02 nm for the low voltage mode). The second one is the 12 µm Z-scanner (1.7 µm in low voltage mode) with a resolution of <0.05 nm (<0.01 nm in low voltage mode) controlling the vertical movement of the probe. Both scanners can be operated in feedback control. Such a scanning arrangement avoids many of the issues of conventional tube-scanners such as background curvature and non-linearity.
A hood protects the SPM against electromagnetic radiation, air movement, and abrupt temperature changes. In addition to that the instrument is placed on an active vibration-control table (MOD-1 plus) by Halcyonics. The system comes with an optical microscope (500x) that facilitates positioning of the laser spot on a cantilever as well as identifying of sample features of interest.
All standard AFM (atomic force microscopy) modes; contact, force-vs.-distance, non-contact, intermittent, and lateral force microscopy (LFM) are available. In addition to the aforementioned the following modes can be carried out: electrostatic force microscopy (EFM), scanning tunnelling microscopy (STM), and I-AFM (a contact AFM mode that allows for local conductivity measurements). A low noise current amplifier (DLPCA-200) by Femto is applied in context of our STM and I-AFM measurements.
In our institute the setup is used to characterize all CVD and PVD synthesised film’s surfaces as well as nanostructured materials such as carbon nanotubes (CNTs), carbon nanobells (CNBs), and others.