A system for performing surface analysis on a material, includes a pulsed electron source that forms a monochromatic beam of incident electrons; means for conveying the incident electrons to the surface of a sample of material, so as to form backscattered electrons, and the backscattered electrons to detecting means, the conveying means comprising at least one electron optical system; means for detecting the backscattered electrons; the pulsed electron source comprising: a source of atoms; a continuous-wave laser beam configured to form a laser excitation zone able to excite the atoms to Rydberg states; a pulsed electric field on either side of the laser excitation zone, the pulsed electric field being configured to ionize at least the excited atoms and to form a monochromatic beam of electrons.

The purpose of the present invention is to be able to acquire high-resolution images in a scanning electron microscope using a combination of a cold cathode (CFE) electron source and a boosting process, even at low accelerating voltage enhancing the current stability of the CFE electron source. A configuration in which a CFE electron source (101), an anode electrode (103) at positive (+) potential, and an insulator (104) for isolating the anode electrode (103) from ground potential are accommodated within a single vacuum chamber (105), and an ion pump (106) and a non-evaporable getter (NEG) pump (107) are connected to the vacuum chamber (105), is employed.

An array of carbon nanotube micro-tip structure includes an insulating substrate and a plurality of patterned carbon nanotube film structures. The insulating substrate includes a surface. The surface includes an edge. A plurality of patterned carbon nanotube film structures spaced from each other. Each of the plurality of patterned carbon nanotube film structures is partially arranged on the surface of the insulating substrate. Each of the plurality of patterned carbon nanotube film structures comprises two strip-shaped arms joined together forming a tip portion protruding and suspending from the edge of the surface of the insulating substrate. Each of the two strip-shaped arms comprises a plurality of carbon nanotubes parallel to the surface of the insulating substrate.

The present disclosure provides an electron source operating method, the electron source including at least one emission site fixed on a tip, the emission site being a reaction product formed by metal atoms of a surface of the tip and gas molecules under an electric field, and the operating method comprises emitting electrons by controlling operating parameters of the electron source.

A carbon nanomaterial functionalized needle tip is modified with a low work function material. The needle tip is formed by combining a carbon nanomaterial with a material of a needle tip through a covalent bond. The interior or outer surface of the carbon nanomaterial is modified with a low work function material. The material of the needle tip is a metal which can be any of tungsten, iron, cobalt, nickel, and titanium. The carbon nanomaterial can be carbon nanocone or carbon nanotube. The tip of the carbon nanomaterial has the same orientation as the metal needle tip. The low work function material can be selected from metals, metal carbides, metal oxides, borides, nitrides, and endohedral metallofullerene. The carbon nanomaterial functionalized needle tip has a lower electron emission barrier, and can effectively reduce the electric field intensity required for electron emission, and improve the emission current and emission efficiency.

A high voltage feedthrough assembly (100) for providing an electric potential in a vacuum environment comprises a flange connector (10) being adapted for a connection with a vacuum vessel (201), wherein the flange connector (10) has an inner side (11) facing to the vacuum vessel (201) and an outer side (12) facing to an environment of the vacuum vessel 201, a vacuumtight insulator tube (20) having a longitudinal extension with a first end (21) facing to the flange connector (10) and a second end (22) being adapted for projecting into the vacuum vessel (201), and an electrode device (30) coupled to the second end (22) of the insulator tube (20), wherein the electrode device (30) has a front electrode (31), including a photocathode or a field emitter tip and facing to the vacuum vessel (201) and a cable adapter (32) for receiving a high-voltage cable (214), wherein a flexible tube connector (40) is provided for a vacuum-tight coupling of the insulator tube (20) with the flange connector (10), and a manipulator device (50) is connected with the insulator tube (20) for adjusting a geometrical arrangement of the insulator tube (20) relative to the flange connector (10). Furthermore, an electron diffraction or imaging apparatus (transmission electron microscope, TEM) 200 for static and/or time-resolved diffraction, including (nano-) crystallography, and real space imaging for structural investigations including the high voltage feedthrough assembly (100) and a method of manipulating an electrode device (30) in a vacuum environment are described.

An electron microscope and method of operating an electron microscope (1) has an electron beam source (11) for producing an electron beam, a noise canceling aperture (12) for detecting a part of the beam, an amplifier (42), an effective value calculating circuit (44) for extracting DC components of the output signal from the amplifier (42), a detector (15) for detecting a signal obtained in response to impingement of the beam on a sample (A), a preamplifier circuit (20), an amplifier circuit (30), a dividing circuit (54) for performing a division based on the output signal from the amplifier circuit (30) and on the output signal from the amplifier (42), and a multiplier circuit (58) for performing multiplication of the output signal from the dividing circuit (54) and the output from the effective value calculating circuit (44).

An electron gun includes a cathode that is heated to emit thermions; a cathode heating power supply that supplies a cathode heating current for heating the cathode; a grid that has a first aperture formed therein and that has a grid voltage applied thereto, the grid voltage having a potential lower than that of the cathode, wherein the grid converges the thermions passing through the first aperture by the grid voltage; an anode that has a second aperture formed therein and that has an anode voltage applied thereto, wherein the anode causes the thermions extracted from the cathode to pass through the second aperture as an electron beam by the anode voltage; an anode-voltage power supply that applies the anode voltage to the anode; and a controller that causes the anode voltage having a positive potential to be applied from the anode-voltage power supply to the anode.

An electron gun EG in which mixing of secondary electrons is suppressed is provided. The electron gun EG has an electron source 1, an extraction electrode 2 for extracting an electron beam E1 from the electron source 1, and an acceleration electrode for accelerating the extracted electron beam E1. The extraction electrode 2 includes a diaphragm 4 for allowing a part of the electron beam E1 to pass through, a shield 5 positioned above the diaphragm 4 apart from the diaphragm 4, and a shield 6 positioned below the diaphragm 4 apart from the diaphragm 4. The diaphragm 4 has an opening OP4 having an opening diameter D4, the shield 5 has an opening OP5 having an opening diameter D5 which is greater than the opening diameter D4, and the shield 6 has an opening OP6 having an opening diameter D6 which is greater than the opening diameter D4.

Electron emitters and method of fabricating the electron emitters are disclosed. According to certain embodiments, an electron emitter includes a tip with a planar region having a diameter in a range of approximately (0.05-10) micrometers. The electron emitter tip is configured to release field emission electrons. The electron emitter further includes a work-function-lowering material coated on the tip.