Contact Mode is a primary AFM mode. The probe is a microfabricated cantilever with a sharp tip. Tip and sample are in perpetual contact during the raster-scan. Detector signal is a measure of cantilever deflection in Z. In feedback mode, output signal usually adjusts the Z position of the scanner to maintain a deflection setpoint. This mode enables numerous secondary modes, including LFM, Force Modulation, SCM, SSRM, TUNA, and CAFM.