Patent classifications
G01N23/2254
Accurate wavelength calibration in cathodoluminescence SEM
A scanning electron microscope having a spectrometer with a sensor having a plurality of pixels, wherein the spectrometer directs different wavelengths of collected light onto different pixels. An optical model is formed and an error function is minimized to find values for the model, such that wavelength detection may be corrected using the model. The model can correct for errors generated by effects such as the motion of the electron beam over the specimen, aberrations introduced by optical elements, and imperfections of the optical elements. A correction function may also be employed to account for effects not captured by the optical model.
Dislocation type and density discrimination in semiconductor materials using cathodoluminescence measurements
A cathodoluminescence microscope and method are used to identify and classify dislocations within a semiconductor sample. At least two CL polarized images are concurrently obtained from the sample. The images are added together to obtain a total intensity image. A normalized difference of the images is taken to obtain a degree of polarization (DOP) image. The total intensity and DOP images are compared to differentiate between edge dislocations and screw dislocations within the sample. Edge dislocation density and screw dislocation density may then be calculated.
Dislocation type and density discrimination in semiconductor materials using cathodoluminescence measurements
A cathodoluminescence microscope and method are used to identify and classify dislocations within a semiconductor sample. At least two CL polarized images are concurrently obtained from the sample. The images are added together to obtain a total intensity image. A normalized difference of the images is taken to obtain a degree of polarization (DOP) image. The total intensity and DOP images are compared to differentiate between edge dislocations and screw dislocations within the sample. Edge dislocation density and screw dislocation density may then be calculated.
Methods of inspecting samples with multiple beams of charged particles
Disclosed herein is an apparatus comprising: a source configured to emit charged particles, an optical system and a stage; wherein the stage is configured to support a sample thereon and configured to move the sample by a first distance in a first direction; wherein the optical system is configured to form probe spots on the sample with the charged particles; wherein the optical system is configured to move the probe spots by the first distance in the first direction and by a second distance in a second direction, simultaneously, while the stage moves the sample by the first distance in the first direction; wherein the optical system is configured to move the probe spots by the first distance less a width of one of the probe spots in an opposite direction of the first direction, after the stage moves the sample by the first distance in the first direction.
Methods of inspecting samples with multiple beams of charged particles
Disclosed herein is an apparatus comprising: a source configured to emit charged particles, an optical system and a stage; wherein the stage is configured to support a sample thereon and configured to move the sample by a first distance in a first direction; wherein the optical system is configured to form probe spots on the sample with the charged particles; wherein the optical system is configured to move the probe spots by the first distance in the first direction and by a second distance in a second direction, simultaneously, while the stage moves the sample by the first distance in the first direction; wherein the optical system is configured to move the probe spots by the first distance less a width of one of the probe spots in an opposite direction of the first direction, after the stage moves the sample by the first distance in the first direction.
METHOD FOR IMPROVING AN EBSD/TKD MAP
A method for improving the quality/integrity of an EBSD/TKD map, wherein each data point is assigned to a corresponding grid point of a sample grid and represents crystal information based on a Kikuchi pattern detected for the grid point; comprising determining a defective data point of the EBSD/TKD map and a plurality of non-defective neighboring data points, comparing the position of Kikuchi bands of a Kikuchi pattern detected for a grid point corresponding to the defective data point with the positions of bands in at least one simulated Kikuchi pattern corresponding to crystal information of the neighboring data points and assigning the defective data point the crystal information of one of the plurality of neighboring data point based on the comparison.
Defect Inspection Device and Defect Inspection Method
Provided is a quantification method for evaluating the quality of a sample on the basis of a mirror electron image acquired by a mirror electron microscope. In this invention, a mirror electron image is expressed numerically through counting of the brightness values of each pixel composing the mirror electron image, the creation of a brightness histogram, and the calculation, from the distribution of the brightness histogram, of a standard deviation. If brightness contrast is formed on the mirror electron image by, for example, a scratch on or latent damage in a sample, because the brightness values of the pixels will fluctuate, there will be more variation in the brightness values than in an image obtained from a satisfactory sample with no defects, and this will result in the brightness values of the mirror electron image having a larger standard deviation. The standard deviation indicates the variation in the brightness calculated from the mirror electron image and essentially represents the degree of defect contrast in the sample. This value can be used as a basis for simply evaluating the quality of a sample while eliminating subjectivity and ambiguity.
Apparatus for wavelength resolved angular resolved cathodoluminescence
Apparatuses for collection of wavelength resolved and angular resolved cathodoluminescence (WRARCL) emitted from a sample exposed to an electron beam (e-beam) or other excitation beams are described. Cathodoluminescence light (CL) may be emitted from a sample at specific angles relative to the excitation beam and analyzed with respect to light-emitting and other optical phenomena. The described embodiments allow collection of WRARCL data more efficiently and with significantly fewer aberrations than existing systems.
ACCURATE WAVELENGTH CALIBRATION IN CATHODOLUMINESCENCE SEM
A scanning electron microscope having a spectrometer with a sensor having a plurality of pixels, wherein the spectrometer directs different wavelengths of collected light onto different pixels. An optical model is formed and an error function is minimized to find values for the model, such that wavelength detection may be corrected using the model. The model can correct for errors generated by effects such as the motion of the electron beam over the specimen, aberrations introduced by optical elements, and imperfections of the optical elements. A correction function may also be employed to account for effects not captured by the optical model.
APPARATUS FOR WAVELENGTH RESOLVED ANGULAR RESOLVED CATHODOLUMINESCENCE
Apparatuses for collection of wavelength resolved and angular resolved cathodoluminescence (WRARCL) emitted from a sample exposed to an electron beam (e-beam) or other excitation beams are described. Cathodoluminescence light (CL) may be emitted from a sample at specific angles relative to the excitation beam and analyzed with respect to light-emitting and other optical phenomena. The described embodiments allow collection of WRARCL data more efficiently and with significantly fewer aberrations than existing systems.