The invention relates to a method, a device and a system for the treatment of biological frozen samples using plasma focused ion beams (FIB). The samples can then be used for mass spectrometry (MS), genomics, such as gene sequencing analysis or next generation sequencing (NGS) analysis, and proteomics. The present invention particularly relates to a method of treatment of at least one biological sample. This method is particularly used for high performance microscopy, proteomics analytics, sequencing, such as NGS etc. According to the present invention the method comprises the steps of providing at least one biological sample in frozen form. The milling treats at least one part of the sample by a plasma ion beam comprising at least one of an O.sup.+ and/or a Xe.sup.+ plasma.

Since a diffraction phenomenon occurs in the electron beam passing through a differential evacuation hole, an electron beam whose probe diameter is narrowed cannot pass through a hole having an aspect ratio of a predetermined value or more, and accordingly, a degree in vacuum on the electron beam side cannot be improved. By providing a differential evacuation hole with a high aspect ratio in an ion beam device, it becomes possible to obtain an observed image on a sample surface, with the sample being placed under the atmospheric pressure or a pressure similar thereto, in a state where the degree of vacuum on the ion beam side is stabilized. Moreover, by processing the differential evacuation hole by using an ion beam each time it is applied, both a normal image observation with high resolution and an image observation under atmospheric pressure or a pressure similar thereto can be carried out.

Provided is a tip capable of repeatedly regenerating a single-atom termination structure in which a distal end is formed of only one atom. A tip (1) having a single-atom termination structure includes: a thin line member (2) made of a first metal material; a protruding portion (4) made of a second metal material, which is formed at least in a distal end portion (2a) of the thin line member (2), and has a distal end terminated with only one atom; and a supply portion (5) made of the second metal material to be supplied to the protruding portion (4), which is formed in the vicinity of the distal end portion (2a) of the thin line member (2).

An object of the invention is to provide an ion beam device capable of sharpening an emitter tip end to an atomic level with high reproducibility while reducing a device downtime. The ion beam device according to the invention measures a current of a helium ion beam, and switches, according to a measurement result, between a first operation of adjusting a flow rate of a nitrogen gas or an oxygen gas and a second operation of adjusting an extraction voltage.

In this invention, vibrations generated by a freezer from a cooling mechanism for cooling an ion source emitter tip are prevented from being transmitted to the emitter tip as much as possible, while the cooling capability of the cooling mechanism is improved widely. The ion beam device (10) is equipped with: an ion source housing (22) provided with an emitter tip (45) and defining an ion source chamber (27) supplied with an ionization gas or gas molecules; a gas pot (51) provided in the ion source chamber (27) so as to be thermally connected to the emitter tip (45) and accommodated so as to have no direct physical contact with a cooling stage (57) of a freezer (52); and a spacer (59) provided on the peripheral surface of the cooling stage (57) housed by the gas pot (51) and maintaining a given interval or greater between the peripheral surface of the cooling stage (57) and the internal peripheral surface of the gas pot (52).

A device including an imaging-type or a projection-type ion detection system and being capable of performing observation or inspection at high speed with an ultrahigh resolution in a sample observation device using an ion beam is provided. The device includes a gas field ion source that generates an ion beam, an irradiation optical system that irradiates a sample with the ion beam, a potential controller that controls an accelerating voltage of the ion beam and a positive potential to be applied to the sample and an ion detection unit that images or projects ions reflected from the sample as a microscope image, in which the potential controller includes a storage unit storing a first positive potential allowing the ion beam to collide with the sample and a second positive potential for reflecting the ion beam before allowing the ion beam to collide with the sample.

A gas field ionization source in which an ion beam current is stable for a long time is achieved in an ion beam apparatus equipped with a field ionization source that supplies gas to a chamber, ionizes the gas, and applies the ion beam to a sample. The ion beam apparatus includes an emitter electrode having a needle-like extremity; a chamber inside which the emitter electrode is installed; a gas supply unit that supplies the gas to the chamber; a cooling unit that is connected to the chamber and cools the emitter electrode; a discharge type exhaust unit that exhausts gas inside the chamber; and a trap type exhaust unit that exhausts gas inside the chamber. The exhaust conductance of the discharge type exhaust unit is larger than the total exhaust conductance of the trap type exhaust unit.

An H.sub.3.sup.+ ion is used as an ion beam to achieve improvement in focusing capability influencing observed resolution and machining width, improvement in the beam stability, and a reduction in damage to the sample surface during the beam irradiation, in the process of observation and machining of the sample surface by the ion beam. The H.sub.3.sup.+ ion can be obtained by use of a probe current within a voltage range 21 around a second peak 23 occurring when an extracted voltage is applied to a needle-shaped emitter tip with an apex terminated by three atoms or less, in an atmosphere of hydrogen gas.

Provided is an ion beam system including a gas field ionization ion source which can obtain a high current sufficient for processing and stabilize an ion beam current. The ion beam system includes a gas field ionization ion source which includes: a vacuum vessel; an emitter tip holder disposed in the vacuum vessel; an emitter tip connected to the emitter tip holder; an extraction electrode opposed to the emitter tip; a gas supply portion for supplying a gas to the emitter tip; and a cold transfer member disposed in the vacuum vessel and transferring cold energy to the emitter tip holder. The cold transfer member has its surface covered with a heat insulating material in order to prevent the gas condensation.

According to an embodiment of the present invention, an ion beam apparatus switches between an operation mode of performing irradiation with an ion beam most including H.sub.3.sup.+ ions and an operation mode of performing irradiation with an ion beam most including ions heavier than the H.sub.3.sup.+.