International Business Machines Corporation

Iowa State University Research Foundation Inc

Deepak Ranjan Sahoo

Charalampos Pozidis

Abu Sebastian

Murti V Salapaka

Venkataraman Kartik

Urs T Duerig

Angeliki Pantazi

Michel Despont

Armin W Knoll

Walter Haeberle

Peter Baechtold

Gian R Salis

Michael Despont

Tathagata De

Pranav Agarwal

A device including a first part and a second part, the first and second part being connected to each other and being movable relative to each other. The first part is a cantilever that has a rectangular strip with a probe tip at one end and a magnetic element the other end. The magnetic element is configured to interact with a magnetic field. The first part is connected to the second part by a hinge.

Device comprising a cantilever and scanning system

An apparatus is provided and includes a cantilever having a tip at a distal end thereof disposed with the tip positioned an initial distance from a sample and a circuit electrically coupled to a substrate on which the sample is layered and the cantilever to simultaneously apply direct and alternating currents to deflect the cantilever and to cause the tip to oscillate about a point at a second distance from the sample, which is shorter than the initial distance, between first positions, at which the tip contacts the sample, and second positions, at which the tip is displaced from the sample.

Dynamic mode nano-scale imaging and position control using deflection signal direct sampling of higher mode-actuated microcantilevers

A device including a first part and a second part, one of which is a cantilever, the first and second parts being connected to each other and movable relative to each other. The device includes a magnetic element arranged on the first part and configured to provide a magnetic field. The device further includes a magnetization device arranged on the second part and configured to provide an actuation magnetic field which interacts with the magnetic field of the magnetic element, thereby causing or suppressing relative movement of the first and second parts. A scanning system including such a device is also described.

A micro-electro mechanical device includes a first structure, a second structure offset from the first structure by a gap. The first structure is configured to be electrostatically actuated to deflect relative to second structure. A pulse generator is configured to combine at least two different pulses to electrostatically drive at least one of the first structure and the second structure between an initial position and a final position.

High-speed electrostatic actuation of MEMS-based devices

A position sensor and method include a magnetic component, a first magneto-resistive sensor disposed in proximity to the magnet/coil; and a second magneto-resistive sensor disposed in proximity to the magnetic component and the first magneto-resistive sensor. The first magneto-resistive sensor and second magneto-resistive sensor are configured to sense changes in a stray magnetic field created by the magnetic component in accordance with a relative positional change between the magnetic component and the first and second magneto-resistive sensors.

Magneto-resistance based nano-scale position sensor

A topography sensor and method include a probe configured to traverse a surface to determine a topography. A stray magnetic field is disposed in proximity to the probe. A magneto-resistive sensor is configured so that the stray magnetic field passing through it changes in accordance with positional changes of the probe as the probe tip traverses the surface.

Magneto-resistance based topography sensing

An observer based Q control method for a cantilever in an atomic force microscopy is provided that provides for a 'dual' Q behavior such that a particular effective Q is achieved when a sample is present and another effective Q when a sample is absent. In the control method, the transfer function from dither input to photo-diode output is independent of the observer so that the cantilever effectively behaves like a spring-mass-damper system. The effective quality factor and stiffness of the cantilever can be changed by appropriately choosing the state feedback gain. The method provides sample-imaging using transient atomic force microscopy.

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An approach to determine cantilever movement is presented. An observer based state estimation and statistical signal detection and estimation techniques are applied to Atomic Force Microscopes. A first mode approximation model of the cantilever is considered and an observer is designed to estimate the dynamic states. The cantilever-sample interaction is modeled as an impulsive force applied to the cantilever in order to detect the presence of sample. A generalized likelihood ratio test is performed to obtain the decision rule and the maximum likelihood estimation of the unknown arrival time of the sample profile and unknown magnitude of it. The use of the transient data results in sample detection at least ten times faster than using the steady state characteristics.

Method to transiently detect sample features using cantilevers

An approach to detect when a cantilever loses interaction with a sample, thereby detecting when a portion of an image obtained using a cantilever is spurious is presented. An observer based estimation of cantilever deflection is compared to the cantilever deflection and the resulting innovation is used to detect when the cantilever loses interaction. The loss of interaction is determined when the innovation is outside of and/or below a threshold level.

Real time detection of loss of cantilever sensing loss

An approach to determine cantilever movement is presented. An observer based state estimation and statistical signal detection and estimation techniques are applied to Atomic Force Microscopes. A first mode approximation model of the cantilever is considered and a Kalman filter is designed to estimate the dynamic states. The tip-sample interaction is modeled as an impulsive force applied to the cantilever in order to detect the presence of sample. A generalized likelihood ratio test is performed to obtain the decision rule and the maximum likelihood estimation of the unknown arrival time of the sample profile and unknown magnitude of it. The use of the transient data results in sample detection at least ten times faster than using the steady state characteristics.

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Deepak Ranjan Sahoo