A method and apparatus to measure overlay from images of metrology targets, images obtained using acoustic waves, for example images obtained using an acoustic microscope. The images of two targets are obtained, one image using acoustic waves and one image using optical waves, the edges of the images are determined and overlay between the two targets is obtained as the difference between the edges of the two images.

Method of determining an overlay error between device layers of a multilayer semiconductor device using an atomic force microscopy system, wherein the semiconductor device comprises a stack of device layers comprising a first patterned layer and a second patterned layer, and wherein the atomic force microscopy system comprises a probe tip, wherein the method comprises: moving the probe tip and the semiconductor device relative to each other for scanning of the surface; and monitoring motion of the probe tip with tip position detector during said scanning for obtaining an output signal; during said scanning, applying a first acoustic input signal to at least one of the probe or the semiconductor device; analyzing the output signal for mapping at least subsurface nanostructures below the surface of the semiconductor device; and determining the overlay error between the first patterned layer and the second patterned layer based on the analysis.

A photoacoustic microscope includes: a light source which generates pulse light; a focusing optical system which focuses the pulse light emitted from the light source and irradiate a sample with the focused pulse light; a photoacoustic signal detection unit which detects an acoustic signal generated from the sample through irradiation of the pulse light; an image signal formation unit which forms an image signal of the sample based on the acoustic signal; an information unit having information representing a relation between intensity of the pulse light entering the sample and intensity of the acoustic signal generated from the sample; and a pulse light intensity changing unit which changes intensity of the pulse light from the light source based on the information.

The present document relates to a method of performing defect detection on a self-assembled monolayer of a semiconductor element or semi-manufactured semiconductor element, using an atomic force microscopy system. The system comprises a probe with a probe tip, and is configured for positioning the probe tip relative to the element for enabling contact between the probe tip and a surface of the element. The system comprises a sensor providing an output signal indicative of a position of the probe tip. The method comprises: scanning the surface with the probe tip; applying an acoustic vibration signal to the element; obtaining the output signal indicative of the position of the probe tip; monitoring probe tip motion during said scanning for mapping the surface of the semiconductor element, and using a fraction of the output signal for mapping contact stiffness indicative of a binding strength.

An acoustic analysis device based on atomic force microscopy for the volume analysis of an organic or inorganic sample includes a support on which the sample is immobilized, and an atomic force microscopy lever having a free end provided with a part that interacts with an upper face of the sample and scans said upper face, one or at least two of the independent piezoelectric actuators supplying ultrasonic waves with interferential coupling, and acoustic measurement and analysis bodies associated with the atomic force microscopy lever. The support is a total reflection prism to which the piezoelectric actuators are applied, and the piezoelectric actuators are applied in determined positions on said prism in order to define determined angles of excitation of the ultrasonic waves.

The present invention relates to a heterodyne scanning probe microscopy method for imaging structures on or below the surface of a sample, the method including applying, using a transducer, an acoustic input signal to the sample sensing, using a probe including a probe tip in contact with the surface, an acoustic output signal, wherein the acoustic output signal is representative of acoustic surface waves induced by the acoustic input signal wherein the acoustic input signal comprises at least a first signal component having a frequency above 1 gigahertz, and wherein for detecting of the acoustic output signal the method comprises a step of applying a further acoustic input signal to at least one of the probe or the sample for obtaining a mixed acoustic signal, the further acoustic input signal including at least a second signal component having a frequency above 1 gigahertz, wherein the mixed acoustic signal comprises a third signal component having a frequency equal to a difference between the first frequency and the second frequency, wherein the frequency of the third signal component is below 1 gigahertz.

A system and method for using a microscope to aurally observe a specimen in a fluid is provided. In one embodiment of the present invention, the microscope is modified to include a first beam splitter, splitting a visual of the specimen magnified by the objective lens. A first beam is then provided to an audio frequency modulation sensing (AFMS) device, whose function is to sense photoacoustic modulation of the specimen and to extract aural data, allowing sound energy to be observed by a user (e.g., displayed on screen, played on a speaker, etc.). The second beam is provided to a second beam splitter, allowing visuals to be provided to the eyepiece and to at least one other sensor, where a second visual of the specimen is captured. The second visual can then be displayed on a screen in time synchronization with aural data provided by the AFMS device.

A photoacoustic microscope includes a light source, an objective lens, a light scanner, a photoacoustic wave detector, and a calculation unit. The light source emits excitation light. The objective lens focuses the excitation light within a specimen. The light scanner scans the specimen with the excitation light. The photoacoustic wave detector detects photoacoustic waves. The calculation unit uses a correlation coefficient to calculate a shift in waveform due to a change over time in photoacoustic waves between a standard position and a calculation position. The calculation unit calculates the depth from the standard position at the calculation position based on the shift.

Method of tuning parameter settings for performing acoustic scanning probe microscopy for subsurface imaging, scanning probe microscopy system, and computer program product. This document relates to a method of tuning a scanning probe microscopy system. The method comprises: a) applying an acoustic vibration signal comprising a first frequency and a second frequency to a sample; b) at a first position of the probe tip, sweeping the first frequency across a first frequency range, and obtaining a first signal; c) at a second position of the probe tip, sweeping the first frequency across at least said first frequency range, and obtaining a second signal; d) analyzing the first and second signals to obtain a difference characteristic dependent on the first frequency. The first and second position are selected such that a subsurface structure of the sample at the first and second position is different.

An acoustic wave acquisition apparatus moves a probe so that, in a case where a distance between a probe positioned at a first point and a second point corresponding to a target position is below a predetermined threshold value, a ratio of a length of a trajectory to a distance between the first point and the second point is larger than in a case where the distance between the probe and the second point exceeds the predetermined threshold value.