A method to perform sub-surface detection of nanostructures in a sample, uses an atomic force microscopy system that comprising a scan head having a probe with a cantilever and a probe tip arranged on the cantilever. The method comprises: moving the probe tip and the sample relative to each other in one or more directions parallel to the surface for scanning of the surface with the probe tip; and monitoring motion of the probe tip relative to the scan head with a tip position detector during said scanning for obtaining an output signal. During said scanning acoustic vibrations are induced in the probe tip by applying a least a first and a second acoustic input signal respectively comprising a first and a second signal component at mutually different frequencies above IGHz, differing by less than IGHz to the probe, and analyzing the output signal for mapping at least subsurface nanostructures below the surface of the sample.

Methods and apparatus for obtaining extremely high sensitivity chemical composition maps with spatial resolution down to a few nanometers. In some embodiments these chemical composition maps are created using a combination of three techniques: (1) Illuminating the sample with IR radiation than is tuned to an absorption band in the sample; and (2) Optimizing a mechanical coupling efficiency that is tuned to a specific target material; (3) Optimizing a resonant detection that is tuned to a specific target material. With the combination of these steps it is possible to obtain (1) Chemical composition maps based on unique IR absorption; (2) spatial resolution that is enhanced by extremely short-range tip-sample interactions; and (3) resonant amplification tuned to a specific target material. In other embodiments it is possible to take advantage of any two of these steps and still achieve a substantial improvement in spatial resolution and/or sensitivity.

An atomic force microscope and method for detecting photo-induced force using the atomic force microscope utilizes light from a photonic source at a tip-sample interface that results in photo-induced force gradient, which is detected by measuring a resonant frequency of a vibrational mode of a cantilever of the atomic force microscope.

An atomic force microscope includes a raster scan control mechanism configured to perform a raster scan between a cantilever having a probe at a free end and a sample relative to each other across an XY plane in a fluid, an interaction control mechanism configured to vibrate the cantilever and to control an interaction generated between the probe and the sample, and a sample information acquisition circuit configured to acquire sample information including inclination information of a sample surface with respect to the XY plane based on a control result of the interaction control mechanism. The interaction control mechanism is configured to control the interaction generated between the probe and the sample in accordance with inclination of the sample surface with respect to the XY plane.

A method for obtaining optical spectroscopic information about a sub-micron region of a sample with quantitatively controlled depth/volume of the sample subsurface using a scanning probe microscope. With controlled probing depth/volume, the method can separate top surface data from subsurface optical/chemical information. The method can also be applied in liquid suitable for studying biological and chemical samples in their native aqueous environments, as opposed to air. In the method, a depth-controlled spectrum of the surface layer is constructed by illuminating the sample with a beam of infrared radiation and measuring a probe response using at least one of the resonant frequencies of the probe. The surface sensitivity is obtained by limiting the heat diffusion effect of the subsurface so as to confine the signal. The signal confinement is achieved through non-linearity of the acoustic wave with probe, as well as benefits gained by a high modulation frequency of the infrared radiation source at >1 MHz.

Method and system for performing characterization of a sample using an atomic force microscopy system. An actuation signal is provided to a photo-thermal actuator which is configured to excite the probe by means of an optical excitation beam incident on the cantilever. The probe is configured to be bendable by means of the optical excitation beam impinging on it. The actuation signal is configured to include at least one modulation frequency. The probe tip motion is monitored for determining at least a subsurface characterization data.

The disclosure is directed to a method and apparatus for correcting responsivity variation in photothermal imaging. The method includes sending, during a first time period, light-driving signal to a light source so that the light source is configured to output a series of light pulses onto a sample, wherein the sample is under photothermal-induced expansion according to the series of light pulses. The method includes obtaining, during the first time period, first deflection signal from a cantilever. The method includes sending, during a second time period, actuator-driving signal to an electromechanical actuator so that the electromechanical actuator is configured to move according to the actuator-driving signal, wherein the electromechanical actuator is coupled with the sample. The method includes obtaining, during the second time period, second deflection signal from the cantilever and obtaining a photothermal image of the sample based on the first deflection signal and the second deflection signal.

The present document relates to a method of determining an overlay or alignment error between a first and a second device layer of a multilayer semiconductor device (26) using an atomic force microscopy system (20). The system comprises a scan head (22) including a probe (28). The probe includes a cantilever and a probe tip (30). The method comprises moving the probe tip and the semiconductor device relative to each other for scanning of the surface of the semiconductor device with the probe tip, wherein the probe tip is intermittently or continuously in contact with the surface during scanning. During scanning a signal application actuator (70) applies an acoustic input signal to the substrate, and motion of the probe tip is monitored with a tip position detector for obtaining an output signal, to be analyzed for mapping subsurface structures in different device layers. The signal application actuator includes a shear wave actuator to apply a shear acoustic wave (90) in the substrate. The output signal (39) is indicative of torsional deflection of the probe tip. The document further describes a system.

An apparatus and method of performing sample characterization with an AFM and a pulsed IR laser directed at the tip of a probe of the AFM. The laser pulses are synchronized with the oscillatory drive of the AFM and may only interact with the tip/sample on selected cycles of the oscillation. Peak force tapping mode is preferred for AFM operation. Nano-mechanical and nano-spectroscopic measurements can be made with sub-50 nm, and even sub-20 nm, resolution.

A torsional probe for a metrology instrument includes a cantilever coupled to a support structure via a torsion bar. The cantilever, support structure, and arms of torsion bar have substantially the same thickness.