Conductive AFM simultaneously images topography and conductivity of the sample surface. The local conductivity of a sample is acquired by placing a conducting cantilever on the sample surface and applying a bias between the cantilever and the sample. Conductive AFM detects the resulting current flow, which can be as low as a few pA. The typically low level of current measurement requires a detection scheme with a current noise level of sub pA. Park Systems offers three current sensing options, detecting current signals from sub pA to mA.

• Ulta-Low Noise Conductive AFM(ULCA): < 0.1 pA noise level
• Variable Enhanced Conductive AFM(VECA): < 0.3 pA noise level
• Internal Conductive AFM:< 1 pA noise level

Schematic diagram of the Park AFMs Conductive AFM system