Fei Comapny

Thermo Fisher Scientific (bremen) Gmbh

Kun Liu

Alan S Bahm

Gregory A Schwind

Marcus Straw

Joseph Christian

Aaron Torok

Jeff Kosmoski

Josh Gilbert

Dmitry Grinfeld

Tom Nichols

Alexander Alekseevich Makarov

Neil J Bassom

Alexander A Makarov

George Y Gu

Thomas J Gannon

Alexander Henstra

Peter Christiaan Tiemeijer

Chad Rue

Pleun Dona

Wilko Balschun

Steven J Randolph

Sean Kellogg

Lynwood W Swanson

Ali Mohammadi-Gheidari

Erik Rene Kieft

Gerbert Jeroen Van De Water

Kyle Fort

Joshua Mutch

Lynwood Swanson

Apparatus and methods are disclosed for a mechanically stable, long-life, cold field emitter assembly which is compatible with ultra-high vacuum and occasional high-temperature flashing. A metal adapter is welded between a hexaboride electrode and a metal filament. Some embodiments use a tungsten filament, a tantalum adapter, and a LaB6 microrod electrode with a nanorod emitter tip. Other material combinations are disclosed, as also usage in electron sources for electron microscopes. In variations, the adapter is deposited onto the filament and the electrode then welded to the adapter.

Electrode and filament coupled by adapter

Systems and method for the preparation and delivery of biological samples for charged particle analysis are disclosed herein. An example system at least includes an ion filter coupled to select a sample ion from an ionized sample supply, the ion filter including a quadrupole filter to select the sample ion from the sample supply, an energy reduction cell coupled to receive the selected sample ion and reduce a kinetic energy of the sample ion, a validation unit coupled to receive the sample ion and determine whether the sample ion is a target sample ion, a substrate coupled to receive the sample, wherein the substrate is electron transparent, an ion transport module coupled to receive the sample ion from the ion filter and transport the sample ion to the substrate, and an imaging system arranged to image, with a low energy charged particle beam, the sample located on the substrate, wherein the substrate is arranged in an analysis location. The imaging system including a charge particle emitter coupled to direct coherent charged particles toward the sample; and a detector arranged to detect interference patterns formed from interaction of the coherent charged particles and the sample.

System and method for preparation and delivery of biological samples for charged particle analysis

Apparatuses and methods for improved reconstructions of electron-based holograms are disclosed herein. An example method at least includes forming a hologram of a sample and a known object, forming a reconstruction of the known object using a reconstruction algorithm, comparing the reconstruction of the known object to a reference reconstruction of the known object, and adjusting the reconstruction algorithm based on the comparison of the reconstruction of the known object to the reference reconstruction of the known object. The example method may further include forming a reconstruction of the sample using the adjusted reconstruction algorithm.

Reconstruction algorithms of electron-based holograms

An electron source has an insulating base, a pair of conductive terminals, an insulating support member, a drift isolation member, an emitter-cathode, and one or more heating elements. The conductive terminals are exposed from a first surface of the insulating base. The insulating support member extends from the first surface of the insulating base. The drift isolation member is disposed at an end of the insulating support member remote from the insulating base. The emitter-cathode is coupled to the drift isolation member. The one or more heating elements are coupled to the conductive terminals and the drift isolation member. The combination of the drift isolation member with the insulating support member can prevent stress-induced drift from impacting position of the emitter-cathode, thereby improving the mechanical stability of the electron source.

Mechanically-stable electron source

A coupling for connecting together vacuum-based analytical systems requiring to be vibrationally isolated, comprising: a tubular connector having a longitudinal axis, the connector comprising a first end for connection to a first analytical system and a flexible portion reducing transmission of vibrations and permitting displacement of the first analytical system in a direction transverse to the longitudinal axis of the connector; and a seal longitudinally separated from the flexible portion, for vacuum sealing between the connector and a second analytical system; wherein the connector contains ion optics for transmitting ions between the first and second analytical systems.

Coupling for connecting analytical systems with vibrational isolation

Methods of producing microrods for electron emitters and associated microrods and electron emitters. In one example, a method of producing a microrod for an electron emitter comprises providing a bulk crystal ingot, removing a first plate from the bulk crystal ingot, reducing a thickness of the first plate to produce a second plate, and milling the second plate to produce one or more microrods. In another example, a microrod for an electron emitter comprises a microrod tip region that comprises a nanoneedle that in turn comprises a nanorod and a nanoprotrusion tip. The microrod and the nanoneedle are integrally formed from a bulk crystal ingot by sequentially: (i) removing the microrod from the bulk crystal ingot; (ii) coarse processing the microrod tip region to produce the nanorod; and (iii) fine processing the nanorod to produce the nanoprotrusion tip.

Method of producing microrods for electron emitters, and associated microrods and electron emitters

A charged particle beam source, such as for use in an electron microscope, can include an electrically conductive support member coupled to a base, a mounting member coupled to the support member and defining a bore, and an emitter member received in the bore and retained by a fixative material layer flowed around the emitter member in the bore.

Charged particle beam source

Charged particle beams (CPBs) are modulated using a beam blanker/deflector and an electrically pulsed extraction electrode in conjunction with a field emitter and a gun lens. With such modulation, CPBs can provide both pulsed and continuous mode operation as required for a particular application, while average CPB current is maintained within predetermined levels, such as levels that promote X-ray safe operation. Either the extraction electrode or the beam blanker/deflector can define CPB pulse width, CPB on/off ratio, or both.

Pulsed CFE electron source with fast blanker for ultrafast TEM applications

A charged particle microscope and a method of operating a charged particle microscope are disclosed. The microscope employs a source for producing charged particles, and a source lens below the source to form a charged particle beam which is directed onto a specimen by a condenser system. A detector collects radiation emanating from the specimen in response to irradiation of the specimen by the beam. The source lens is a compound lens, focusing the beam within a vacuum enclosure using both a magnetic lens having permanent magnets outside the enclosure to produce a magnetic field at the beam, and a variable electrostatic lens within the enclosure.

Gun lens design in a charged particle microscope

The state of an emitter can be determined by measurements of how the current changes with the extraction voltage. A field factor &#x3b2; function is determined by series of relatively simple measurements of charged particles emitted at different conditions. The field factor can then be used to determine derived characteristics of the emission that, in the prior art, were difficult to determine without removing the source from the focusing column and mounting it in a specialized apparatus. The relations are determined by the source configuration and have been found to be independent of the emitter shape, and so emission character can be determined as the emitter shape changes over time, without having to determine the emitter shape and without having to redefine the relation between the field factor and the series of relatively simple measurements, and the relationships between the field factor and other emission parameters.

Determination of emission parameters from field emission sources

A cold field emission (CFE) electron source for a focused electron beam system such as a transmission electron microscope (TEM), scanning transmission electron microscope (STEM), or scanning electron microscope (SEM) is disclosed. The source employs an emitter enclosure electrode behind the CFE tip which, in conjunction with the extractor electrode, defines a closed volume that can be thoroughly cleaned by electron impact desorption (EID) and radiative heating from a heated filament located between the emitter enclosure electrode and extractor electrode. The extractor electrode may have a counterbore which restricts backscattered electrons generated at the extractor from reaching portions of the source and gun which have not been cleaned by EID. Pre-cleaning of the emitter enclosure electrode and extractor electrode prior to cold field emission substantially improves both source emission stability and frequency noise characteristics, enabling source operation over time intervals adequate for application to TEMs, STEMs, and SEMs.

Stable cold field emission electron source

A charge transfer mechanism is used to locally deposit or remove material for a small structure. A local electrochemical cell is created without having to immerse the entire work piece in a bath. The charge transfer mechanism can be used together with a charged particle beam or laser system to modify small structures, such as integrated circuits or micro-electromechanical system. The charge transfer process can be performed in air or, in some embodiments, in a vacuum chamber.

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Portland, OR, United States of America

Kun Liu