Search results
Results From The WOW.Com Content Network
Kelvin probe force microscopy (KPFM), also known as surface potential microscopy, is a noncontact variant of atomic force microscopy (AFM). [ 1 ] [ 2 ] [ 3 ] By raster scanning in the x,y plane the work function of the sample can be locally mapped for correlation with sample features.
The AFM tips are fabricated using silicon micro machining and the precise positioning of the microSQUID loop is achieved using electron beam lithography. [33] The additional attachment of a quantum dot to the tip apex of a conductive probe enables surface potential imaging with high lateral resolution, scanning quantum dot microscopy. [34]
nc-AFM was the first form of AFM to achieve true atomic resolution images, rather than averaging over multiple contacts, both on non-reactive and reactive surfaces. [32] nc-AFM was the first form of microscopy to achieve subatomic resolution images, initially on tip atoms [42] and later on single iron adatoms on copper.
Figure 1: Photograph of an AFM system which can be used for chemical force microscopy. In materials science, chemical force microscopy (CFM) is a variation of atomic force microscopy (AFM) which has become a versatile tool for characterization of materials surfaces.
Overall, the aforementioned characterization methods of tips can be categorized into three major classes. [76] They are as follows: Imaging tip using microscopy is used to take image of tip with microscopy, except scanning probe microscopy (SPM) e.g. scanning tunnelling microscopy (STM), atomic force microscopy (AFM) are reported. [70] [71] [72]
The colloidal probe consists of a colloidal particle of few micrometers in diameter that is attached to an AFM cantilever. The colloidal probe technique can be used in the sphere-plane or sphere-sphere geometries (see figure). One typically achieves a force resolution between 1 and 100 pN and a distance resolution between 0.5 and 2 nm.
The interaction of the tip with the sample modifies the amplitudes, phase shifts and frequency resonances of the excited modes. Those changes are detected and processed by the feedback of the instrument. Several features make bimodal AFM a very powerful surface characterization method at the nanoscale. (i) Resolution.
Topographic (left) and current (right) maps collected with CAFM on a polycrystalline HfO 2 stack. The images show very good spatial correlation. In microscopy, conductive atomic force microscopy (C-AFM) or current sensing atomic force microscopy (CS-AFM) is a mode in atomic force microscopy (AFM) that simultaneously measures the topography of a material and the electric current flow at the ...