Abstract: An electron microscope is offered which can correct chromatic and spherical aberrations without producing residual aberrations. In this microscope, a chromatic aberration-correcting optical system and a spherical aberration-correcting optical system are connected in series (in tandem) via a connection system. That is, the chromatic aberration-correcting optical system and the spherical aberration-correcting optical system are configured independently. Chromatic and spherical aberrations are corrected separately.

Abstract: A scanning transmission electron microscope using optical fibers as optical guiding media. The microscope obtains a high-angle scattering image or a dark-field image from electrons transmitted through a specimen. A scintillator converts electrons transmitted through the specimen into optical signals. The optical fibers couple outputs from the scintillator to the photodetector segments. The connections of the fibers with the photodetector segments are formed into arbitrary shapes.

Abstract: A spherical aberration corrector and method is offered, which is easy to design and which can correct spherical aberration and even six-fold astigmatism in a charged particle beam instrument. The corrector has a first pair of multipole elements for producing a first pair of three-fold symmetric fields in which three-fold astigmatisms produced mutually are canceled out and a second pair of multipole elements for producing a second pair of three-fold symmetric fields in which three-fold astigmatisms produced mutually are canceled out. The second pair of multipole elements produce six-fold astigmatisms angularly spaced by 30° about an optical axis from six-fold astigmatisms produced by the first pair of multipole elements.

Abstract: A scanning transmission electron microscope using optical fibers as optical guiding media. The microscope obtains a high-angle scattering image or a dark-field image from electrons transmitted through a specimen. A scintillator converts electrons transmitted through the specimen into optical signals. The optical fibers couple outputs from the scintillator to the photodetector segments. The connections of the fibers with the photodetector segments are formed into arbitrary shapes.

Abstract: A method for axial alignment of a charged particle beam relative to at least three stages of multipole elements and a charged particle beam system capable of making the axial alignment. Some parts of the orbit of the beam or the distributions of three astigmatic fields, or both, are simultaneously translated in a direction perpendicular to the optical axis such that astigmatisms of the same order and same type due to axial deviations between successive ones of the astigmatic fields cancel.

Abstract: An aberration corrector has two stages of multipole elements each of which has a thickness along the optical axis. Each multipole element produces a static electric or magnetic field of 3-fold symmetry and a static electromagnetic field of 2- or 3-fold symmetry superimposed on the static electric or magnetic field. In each of the multipole elements, the static electromagnetic field is so set that magnetic and electric deflecting forces on an electron beam accelerated by a given accelerating voltage substantially cancel out each other. Thus, chromatic aberration is corrected. Also, spherical aberration is corrected by the static electric or magnetic fields of 3-fold symmetry produced by the multipole elements.

Abstract: A scanning transmission electron microscope (STEM) and method of aberration correction have autocorrelation function calculation means, aberration coefficient calculation means, and feedback control. At least two images are obtained by varying a value at which one of the electron optical means is set. The at least two images are autocorrelated. Iso-intensity lines are fit to aberration functions. Aberration coefficients are obtained based on aberration functions. The feedback controls the electron optical column.

Abstract: A spherical aberration corrector and method is offered, which is easy to design and which can correct spherical aberration and even six-fold astigmatism in a charged particle beam instrument. The corrector has a first pair of multipole elements for producing a first pair of three-fold symmetric fields in which three-fold astigmatisms produced mutually are canceled out and a second pair of multipole elements for producing a second pair of three-fold symmetric fields in which three-fold astigmatisms produced mutually are canceled out. The second pair of multipole elements produce six-fold astigmatisms angularly spaced by 30° about an optical axis from six-fold astigmatisms produced by the first pair of multipole elements.

Abstract: An aberration correction system for use in an electron microscope and which produces a negative spherical aberration and corrects a higher-order aberration. The aberration correction system has three stages of multipole elements which, respectively, produce fields of 3-fold symmetry with respect to the optical axis. Any two stages of multipole elements are disposed in directions not to cancel out the 3-fold fields. However, the three stages of multipole elements are so disposed as to cancel out 3-fold astigmatisms.

Abstract: An aberration corrector has two stages of multipole elements each of which has a thickness along the optical axis. Each multipole element produces a static electric or magnetic field of 3-fold symmetry and a static electromagnetic field of 2- or 3-fold symmetry superimposed on the static electric or magnetic field. In each of the multipole elements, the static electromagnetic field is so set that magnetic and electric deflecting forces on an electron beam accelerated by a given accelerating voltage substantially cancel out each other. Thus, chromatic aberration is corrected. Also, spherical aberration is corrected by the static electric or magnetic fields of 3-fold symmetry produced by the multipole elements.

Abstract: An aberration corrector has two stages of dodecapole (12-pole) elements each of which has first through twelfth poles arranged in this order. Exciting coils of the (4n+1)th poles and the exciting coils of the (4n+2)th poles are alternately connected in series (where n=0, 1, or 2) to produce magnetic fields which are identical in absolute value but mutually opposite in sense relative to the optical axis within a plane perpendicular to the axis. The exciting coils of the (4n+3)th poles and the exciting coils of the (4n+4)th poles are alternately connected in series to produce magnetic fields which are identical in absolute value but mutually opposite in sense relative to the optical axis within the plane perpendicular to the axis.

Abstract: A method and apparatus for correcting aberrations using a Ronchigram. A STEM apparatus has first calculation means for taking autocorrelation of minute regions on a Ronchigram of an amorphous specimen, detection device for detecting aberrations in the beam formed from local angular regions on an aperture plane from the autocorrelation or from Fourier analysis of the autocorrelation, second calculation device for calculating the aberrations based on the results of the detection, and control device for controlling operation for correcting the aberrations based on results of calculations performed by the second calculation device.

Abstract: An aberration for correcting higher-order aberrations with a relatively small number of components is by let N1 being the aberration order at a first location, S1 being the symmetry at the first location, N2 being the aberration order at a second location and S2 being the symmetry at the second location. The produced combination aberration satisfies the following condition set 1 as order=N1+N2?1 and symmetry=|S1+S2| or |S2?S1|. That is two aberration-correcting elements (aberration-introducing elements) corresponding to the first and second locations, respectively. An aberration satisfying the condition set 1 is corrected by making use of the produced combination aberration.

Abstract: A scanning transmission electron microscope (STEM) and method of aberration correction have autocorrelation function calculation means, aberration coefficient calculation means, and feedback control. At least two images are obtained by varying a value at which one of the electron optical means is set. The at least two images are autocorrelated. Iso-intensity lines are fit to aberration functions. Aberration coefficients are obtained based on aberration functions. The feedback controls the electron optical column.

Abstract: An aberration correction system for use in an electron microscope and which produces a negative spherical aberration and corrects a higher-order aberration. The aberration correction system has three stages of multipole elements which, respectively, produce fields of 3-fold symmetry with respect to the optical axis. Any two stages of multipole elements are disposed in directions not to cancel out the 3-fold fields. However, the three stages of multipole elements are so disposed as to cancel out 3-fold astigmatisms.

Abstract: An aberration for correcting higher-order aberrations with a relatively small number of components. Let N1 be the aberration order at a first location. Let S1 be the symmetry at the first location. Let N2 be the aberration order at a second location. Let S2 be the symmetry at the second location. The produced combination aberration satisfies the following condition set 1. order=N1+N2?1 symmetry=|S1+S2| or |S2?S1| That is, two aberration-correcting elements (aberration-introducing elements) corresponding to the first and second locations, respectively, are prepared. An aberration satisfying the condition set 1 is corrected by making use of the produced combination aberration.

Abstract: A chromatic aberration corrector has a relatively simple correction system capable of correcting the electron optical system of a transmission electron microscope for chromatic aberration. Furthermore, high-resolution imaging is enabled. The correction system uses a first multipole element for producing a quadrupole field to produce a concave lens effect. However, surplus two-fold astigmatism is left behind. This two-fold astigmatism is removed by inserting a second multipole element for producing a second quadrupole field. The first and second multipole elements are set to mutually opposite polarities. That is, the two-fold astigmatism is canceled out by combining the first and second multipole elements. A cylindrically symmetrical electron beam having spread can be corrected for chromatic aberration by the concave lens effect.

Abstract: A method and apparatus for correcting aberrations using a Ronchigram. A STEM apparatus has first calculation means for taking autocorrelation of minute regions on a Ronchigram of an amorphous specimen, detection device for detecting aberrations in the beam formed from local angular regions on an aperture plane from the autocorrelation or from Fourier analysis of the autocorrelation, second calculation device for calculating the aberrations based on the results of the detection, and control device for controlling operation for correcting the aberrations based on results of calculations performed by the second calculation device.

Abstract: The present invention provides an apparatus for manufacturing ultra-pure water, characterized in that a decarbonator/degassor and a reverse osmosis equipment for pretreatment of supply water are installed in the upper stream of a multiple effect evaporator. The present invention also provides a method for manufacturing ultra-pure water, characterized in that most of the carbonic groups dissolved in the supply water is degassed by a decarbonating/degassing treatment prior to introducing the water to the multiple effect evaporator, and that most of the scale components such as Ca.sup.++, SO.sub.4.sup.-- and Mg.sup.++ are also eliminated by a reverse osmosis treatment.

Abstract: A degreasing-cleaning method which employs as a liquid cleaning agent pure water having a resistivity of at least 10 megohm-cm and a temperature of at least 50.degree. C. The pure water is sprayed onto the article to be cleaned at a pressure of at least 8 kg/cm.sup.2.