In an atom probe having a vacuum chamber containing a specimen mount and a detector for receiving ions emitted from the specimen, a high vacuum subchamber is provided about the specimen mount, with an aperture in the subchamber allowing passage of emitted ions to the detector. The high vacuum subchamber may be pumped to higher vacuum (lower pressure) than the vacuum chamber, and so long as the pressure in the vacuum chamber is below about 10.sup.−1 Pa, very little gas diffusion takes place through the aperture, allowing higher vacuum to be maintained in the subchamber despite the aperture opening to the chamber. The higher vacuum in the subchamber about the specimen assists in reducing noise in atom probe image data. The aperture may conveniently be provided by the aperture in a counter electrode, such as a local electrode, as commonly used in atom probes.

A method of forming a sample and performing correlative S/TEM and APM analysis is provided wherein a sample containing a region of interest is cut from a bulk of sample material and formed into an ultra-thin lamella. The lamella is then analyzed with an S/TEM to form an image. The lamella sample and mount may then go through a cleaning process to remove any contamination. The lamella containing the ROI is then embedded within a selected material and is formed into a needle-shaped sample. The needle-shaped sample is then analyzed with the APM and the resulting data is merged and correlated with the S/TEM data.

A method for imaging a material to atomic scale by means of a field-ion microscope having a vacuum chamber configured to accommodate the material prepared in the form of a tip and an imaging gas, and an ion detector is provided. The method includes application of a DC electrical potential (VDC) and of a pulsed electrical potential, of which the maximum pulse value is denoted Vimp, so that the tip erodes for a potential value equal to VDC+Vimp; acquisition, by the detector between at least two pulses of the pulsed potential, of series of at least two ion images of the impacts of the ions repelled by the tip onto the detector; and calculation of a quantity characteristic of a trend of the erosion of the tip based on the series of ion images acquired and the adjustment, between each series of images, of the values of VDC and of Vimp such that the quantity characteristic of the trend and the ratio VDC/Vimp remain constant.

The disclosure is directed to techniques in preparing an atom probe tomography (“APT”) specimen. A structure in a semiconductor device is identified as including a test object for an APT procedure. A target region is identified in the structure where an APT specimen will be obtained. The target region is analyzed to determine whether a challenging component feature exists therein. A challenging component may include a hard-to-evaporate material, a hollow region, or a material unidentifiable with respect to the test object, or other structural features that pose a challenge to a successful APT analysis. If it is determined that a challenging component exists in the target region, the challenging component is replaced with a more suitable material before the APT specimen is prepared.

A method for imaging a material to atomic scale by means of a field-ion microscope having a vacuum chamber configured to accommodate the material prepared in the form of a tip and an imaging gas, and an ion detector is provided. The method includes application of a DC electrical potential (VDC) and of a pulsed electrical potential, of which the maximum pulse value is denoted Vimp, so that the tip erodes for a potential value equal to VDC+Vimp; acquisition, by the detector between at least two pulses of the pulsed potential, of series of at least two ion images of the impacts of the ions repelled by the tip onto the detector; and calculation of a quantity characteristic of a trend of the erosion of the tip based on the series of ion images acquired and the adjustment, between each series of images, of the values of VDC and of Vimp such that the quantity characteristic of the trend and the ratio VDC/Vimp remain constant.

The disclosure is directed to techniques in preparing an atom probe tomography (“APT”) specimen. A structure in a semiconductor device is identified as including a test object for an APT procedure. A target region is identified in the structure where an APT specimen will be obtained. The target region is analyzed to determine whether a challenging component feature exists therein. A challenging component may include a hard-to-evaporate material, a hollow region, or a material unidentifiable with respect to the test object, or other structural features that pose a challenge to a successful APT analysis. If it is determined that a challenging component exists in the target region, the challenging component is replaced with a more suitable material before the APT specimen is prepared.

According to one embodiment, an atom probe inspection device includes one or more processors configured to change a two-dimensional position of a detected ion, detect two-dimensional position information of the ion and a flying time of the ion, identify a type of an element of the ion, generate first information under a first condition and second information under a second condition, and generate a reconstruction image of the sample from the first information and the second information.

The disclosed technology relates to a method and apparatus for atomic probe tomography (APT). The APT relates to the 3-dimensional reconstruction of the material of a sample having a free-standing tip, wherein an image is repeatedly obtained of the tip area through ptychography or ankylography, in the course of the APT analysis. In one aspect, imaging of the tip is achieved by directing a coherent light beam in the soft X-ray energy range at the tip during the APT analysis. The photons of the X-ray beam are not affected by the strong electric field around the tip, and thereby allow to determine the image of the tip through the application of a ptychography or ankylography algorithm to the data obtained from a photon detector. The photon detector is positioned to detect interference patterns created by photons which have interacted with the tip area, at different overlapping spots of the tip area, when the X-ray beam is scanned across a plurality of such overlapping areas. The method and apparatus allows real-time monitoring of the tip shape, as well as the feedback of the recorded tip shape in order to take tip deformations into account in the APT analysis.

According to one embodiment, an atom probe inspection device includes one or more processors configured to change a two-dimensional position of a detected ion, detect two-dimensional position information of the ion and a flying time of the ion, identify a type of an element of the ion, generate first information under a first condition and second information under a second condition, and generate a reconstruction image of the sample from the first information and the second information.

Methods and systems for correcting aberrations in atom probe tomography are described. A specimen function associated with a plurality of lattice positions of ions of a specimen in a holder is generated using a transmission electron microscope. An image function associated with x- and y-coordinates and time of flight information for a plurality of ions of the specimen in the holder is generated using a delay line detector mounted on the transmission electron microscope. A transfer function based on the specimen function and the image function is generated. The transfer function comprises information relating to ion trajectory aberrations. An Atom Probe Tomography (APT) image of the specimen is generated based on the specimen function, the image function, and the transfer function. The APT image is adjusted to correct for the ion trajectory aberrations.