An electron exit window foil for use with a high performance electron beam generator operating in a corrosive environment is provided. The electron exit window foil comprises a sandwich structure having a film of Ti, a first layer of a material having a higher thermal conductivity than Ti, and a flexible second layer of a material being able to protect said film from said corrosive environment, wherein the second layer is facing the corrosive environment.

A charged-particle-beam device is provided with a data processing unit that removes, from a detector signal, the effect that scattering of a primary charged-particle beam before the primary charged-particle beam reaches a specimen has on the spot shape of the primary charged-particle beam. For example, when using an electron microscope to observe a specimen in a non-vacuum atmosphere, the effect that scattering of a primary charged-particle beam due to a barrier film or a gas present in a non-vacuum space has on the spot shape of the primary charged-particle beam is removed from a signal acquired by a detector. This makes it easy to obtain high-quality images.

Disclosed is a charged particle beam apparatus wherein a partitioning film capable of transmitting a charged particle beam is provided between a charged particle optical system and a sample, said charged particle beam apparatus eliminating a contact between the sample and the partitioning film even in the cases where the sample has recesses and protrusions. On the basis of detection signals or an image generated on the basis of the detection signals, a distance between a sample and a partitioning film is monitored, said detection signals being outputted from a detector that detects secondary charged particles discharged from the sample due to irradiation of a primary charged particle beam.

A scanning electron microscope according to the present invention enables a column to be detached from a sample installation unit, thereby addressing issues related to the column, such as simple calibration related to the column, tilt of a beam, replacement of consumables, etc., by replacing the entire column. As such, the scanning electron microscope has the advantage of being simply and easily repaired and maintained.

There is provided a radiation transmissive window having high radiation transmissivity. The radiation transmissive window includes: an outer frame having an opening; a radiation transmissive film closing off the opening; and a grid member that partitions the opening into a plurality of small opening portions. The grid member has a first portion, a second portion at a smaller distance to the center of the opening than the first portion, and a third portion at a smaller distance to the center of the opening than the second portion. The first portion is greater in width than the second portion. The second portion is greater in width than the third portion.

There is provided a radiation transmissive window having high radiation transmissivity. The radiation transmissive window includes: an outer frame having an opening; a radiation transmissive film closing off the opening; and a grid member that partitions the opening into a plurality of small opening portions. The grid member has a first portion, a second portion at a smaller distance to the center of the opening than the first portion, and a third portion at a smaller distance to the center of the opening than the second portion. The first portion is greater in width than the second portion. The second portion is greater in width than the third portion.

An electron beam irradiation device includes a vacuum chamber having an electron beam generator inside, a vacuum nozzle, and a window foil on a tip of the vacuum nozzle. The electron beam irradiation device further includes an outer pipe surrounding the vacuum nozzle, a cooling-gas supply unit that supplies cooling gas into a coolant passage formed between the vacuum nozzle and the outer pipe, and a heat-conducting transmission foil fitted to the window foil and contacting the tip of the vacuum nozzle. The heat-conducting transmission foil has a value of at least 6310.sup.3, which is determined by dividing a thermal conductivity [W/(m.Math.K)] by a density [kg/m.sup.3], and a tip part of the vacuum nozzle is made of a material having at least a thermal conductivity of copper.

An electron beam source is provided that includes a vessel forming a chamber, a cathode disposed within the chamber, the cathode comprising a low dimensional electrically conductive material having an anisotropic restricted thermal conductivity, an electrode disposed in the chamber, the electrode being connectable to a power source for applying a positive voltage to the electrode relative to the cathode for accelerating free electrons away from the cathode to form an electron beam when the cathode is illuminated by electromagnetic (EM) radiation such that the cathode thermionically emits free electrons, and an electron emission window in the chamber for passing a generated electron beam out of the chamber. An electron microscope that incorporates the electron beam source is also provided.

An examination container includes a main body, a membrane assembly and a cover. The main body has an accommodating trough for holding sample. The membrane assembly covers an opening end of the accommodating trough. The membrane assembly includes a support body and a membrane. The support body has a first surface and a second surface, wherein the support body is flat and has a first through-hole penetrating through the first surface and the second surface. The membrane is arranged on the second surface side of the support body and has a second through-hole. The second through-hole is opposite to the first through-hole and allows a charged particle beam to pass the second through-hole. The cover is detachably connected to the main body to secure the membrane assembly. The membrane assembly is easy to replace and uses less consumables. An electron microscope using the abovementioned examination container is also disclosed.

An examination container includes a main body, a membrane assembly and a cover. The main body has an accommodating trough for holding sample. The membrane assembly covers an opening end of the accommodating trough. The membrane assembly includes a support body and a membrane. The support body has a first surface and a second surface, wherein the support body is flat and has a first through-hole penetrating through the first surface and the second surface. The membrane is arranged on the second surface side of the support body and has a second through-hole. The second through-hole is opposite to the first through-hole and allows a charged particle beam to pass the second through-hole. The cover is detachably connected to the main body to secure the membrane assembly. The membrane assembly is easy to replace and uses less consumables. An electron microscope using the abovementioned examination container is also disclosed.