Gatan, Inc.

Ropintassco Holdings, L.p.

Paul E Mooney

Ondrej L Krivanek

Alexander Jozef Gubbens

Matthew Lent

John Andrew Hunt

Colin Trevor

Bernd Kraus

Daniel N Bui

Daniel Moonen

Chengye Mao

Niklas Dellby

Henry Shih-Ming Chao

A hybrid arrangement of more than one electron energy conversion mechanism in an electron detector is arranged such that an image can be acquired from both energy converters so that selected high-illumination parts of the electron beam can be imaged with an indirectly coupled scintillator detector and the remainder of the image acquired with the highsensitivity/direct electron portion of the detector without readjustments in the beam position or mechanical positioning of the detector parts. Further, a mechanism is described to allow dynamically switchable or simultaneous linear and counted signal processing from each pixel on the detector so that high-illumination areas can be acquired linearly without severe dose rate limitation of counting and lowillumination regions can be acquired with counting.

Hybrid energy conversion and processing detector

There is disclosed a hybrid arrangement of more than one electron energy conversion mechanism in a detector arranged physically such that the electron image can be acquired from both energy converters in such a manner that selected high-illumination parts of the image can be imaged with an indirectly coupled scintillator detector and the remainder of the image acquired with the high-sensitivity/direct electron portion of the detector without readjustments in the beam position or mechanical positioning of the detector parts. Further, a mechanism to allow dynamically switchable or simultaneous linear and counted signal processing from each pixel of the image so that high-illumination areas can be acquired linearly without the severe dose rate limitation of counting and low-illumination regions can be acquired with counting, the switchover point determined by the dose rate at which signal quality breaks even between linear and counting modes.

Methods are disclosed for removal of outlier pixels from a transmission electron microscopy camera image. One exemplary method includes establishing a desired exposure of n electrons per pixel; exposing the camera to a series of sub-frame exposures to produce a series of sub-frame images; calculating an average image signal of all sub-frame exposures in said series; establishing a threshold selected to achieve a desired number of false positives; evaluating each of said sub-frame exposures for pixels further away from said average than said threshold; and replacing pixels in each of said sub-frame images that exceed said threshold with said average to form corrected sub-frame images.

Method for image outlier removal for transmission electron microscope cameras

Methods are disclosed for correcting vertical line streaks in an interline or full-frame CCD. The method includes the step of subtracting an overscan row from each row of a previous image or from each row of a next image, such that each row of the final image contains the same readout smear effect and such that readout overscan rows contain the same smear information as each row of the final image. The method is also described for use with frame transfer CCDs.

Method for real-time removal of vertical scan streaks in a CCD

Methods for creating reference images of fiber optic sensor plates for use in electron microscopes. The methods include taking of reference images of stripe or dot patterns. The spatial frequency of the stripe or dot patterns is such that image artifacts of the fiber optic stacks is recorded. The reference images can then be used to correct for these artifacts.

Method for creating reference images in electron microscopes

Methods are disclosed for operating a device having a high energy particle detector wherein the particles create first incoming traversal events, outgoing backscatter events, higher-order in and out events and incoming events caused by particles which backscatter out of the device, hit nearby mechanical structures and are scattered back into the device. Exemplary method steps include discriminating incoming traversal events from outgoing backscatter events, higher-order in and out events and incoming events by limiting dose rate to a level at ensures that separate events do not overlap and discriminating events from background and from other events based on total energy in each event; discriminating backscatter events from incoming traversal events based on electron path shape; or determining that a first event and a second event are coincident with each other and separating incoming form backscatter events based on electron path shape and energy level.

Method for discrimination of backscattered from incoming electrons in imaging electron detectors with a thin electron-sensitive layer

A lens-coupled camera for an electron microscope is disclosed. The camera includes a CCD, a scintillator, at least one lens, and a mirror, such that at least the CCD and scintillator are housed in the vacuum chamber of the electron microscope, which has only one vacuum chamber. In a further embodiment, the CCD, scintillator, lens and mirror are affixed to a fixed mechanical linkage such that the CCD, scintillator, lens and mirror move together when the camera is retracted.

Retractable lens-coupled electron microscope camera with image sensor in electron microscope vacuum chamber

A charged particle device is provided comprising a charged particle source configured to direct charged particles in the direction of a specimen under examination and an imaging device configured to convert charged particles to an image representing the specimen. The imaging device comprises a detector defining a pixel array. The detector is configured to generate electric charges for individual pixels of the pixel array such that the electric charges collectively define the image. The imaging device is configured such that a portion of the pixel array can be transitioned between a partially masked state and a substantially unmasked state.

Multi-mode charged particle beam device

A resolution enhancement device is provided which utilizes either high extra-mural absorbent optical fibers in the transfer optic, and/or which uses a transfer optic which is bonded to the scintillator without the use of any glues or adhesives. The device provides improved resolution of electron images from electron microscopes while not reducing the sensitivity of the apparatus.

Resolution enhancement device for an optically-coupled image sensor using high extra-mural absorbent fiber

A resolution enhancement device is provided which utilizes either high extra mural absorbent optical fibers in the transfer optic, and/or which uses a transfer optic which is bonded to the scintillator without the use of any glues or adhesives. The device provides improved resolution of electron images from electron microscopes while not reducing the sensitivity of the apparatus.

Methods and apparatus are provided which improve the performance of electron imaging detectors by reducing the total interaction volume of the detector and/or reducing the energy converting volume of the detector. In one embodiment, a method for improving resolution and reducing noise in an imaging electron detector for an electron microscope is provided and includes the step of decelerating the energetic electrons either before the electrons interact with, or as the electrons interact with, the energy converting volume of an imaging electron detector. In other embodiments, the lateral spatial travel of energetic electrons is limited as they traverse the imaging electron detector, or, the extent of electron back scatter from the energetic electrons is limited.

Methods and apparatus for improving resolution and reducing noise in an image detector for an electron microscope

A method and apparatus are provided for CTD imaging device multiple read-out speeds with optimized operation at all of the available speeds. Image signals from a CTD imaging device are digitally sampled at a defined frequency with the read-out electronics being matched to the defined frequency for optimum operation at that frequency. Digital samples taken during both a first (reset reference) portion of each image signal and a second (image voltage) portion of each image signal are then discarded if taken during a noisy/unstable part of the image signal or accumulated and averaged if taken during a stable part of the image signal. The accumulated and averaged digital samples are then algebraically combined to produce signals representative of an image generated by the CTD imaging device. The read-out speed of the CTD imaging device is a fraction of the sampling speed and can be selected by setting an integer divisor for the defined sampling frequency. Selected ones of the samples are retained based on the selected read-out speed. For the fastest read-out speed, the number of samples taken per imaging signal is one and the divisor is equal to one. Selected slower speeds determine which samples are discarded and which samples are accumulated, averaged and combined to produce signals representative of an image generated by the CTD imaging device.

Method and apparatus for multiple read-out speeds for a CTD

An apparatus designed to be positioned in the projection chamber of an electron microscope to detect electron images and/or diffraction patterns from a sample and convert those electron images into light images is provided. The apparatus transfers light images to an imaging sensor for recording while enhancing resolution of the light images by absorbing substantially all laterally scattered light before it reaches the imaging sensor.

Resolution-enhancement device for an optically-coupled image sensor for

An apparatus for improving the resolution of images produced by an electron microscope is provided and includes an electron beam forming an electron image, a support structure mounted in the path of the electron beam, with the support structure transmitting the electron image. Scintillating material is coated onto the side of the support structure opposite that on which the electron image is incident, the scintillating material converting the electron image into a light image. A mirror is provided for deflecting the optical path of the light image into a CCD camera positioned to receive and record the light image.

Growing community of inventors

San Leandro, CA, United States of America

Paul E Mooney