Patent ID: 8689358
Filing Date: 2014-04-01
Classification: G01Q

Abstract:
1. An apparatus, comprising: a cantilever, having a distal end tip, disposed with the tip positioned at a first point at an initial distance from a sample; and a circuit, which is electrically coupled to a substrate on which the sample is layered and the cantilever, the circuit being configured to apply a low frequency deflection signal carrying topography information of the sample to deflect the cantilever toward the sample, the deflection signal being insufficient to cause the tip to come into contact with the sample such that the tip is displaced to a second point at a second distance from the sample, which is shorter than the initial distance, and, simultaneously with the application of the deflection signal, the circuit being further configured to apply alternating current to the tip to thereby cause the tip to oscillate about the second point between tip-sample contact positions and tip-sample non-contact positions, and wherein the circuit comprises a direct current source and an alternating current source disposed in series between a substrate on which the sample is layered and the cantilever.