Abstract: A needle thread feeding assembly in which the thread is positively fed at a desired stitch pitch while being clamped in between a presser roller and a drive roller, whose rotation is frictionally transmitted from a drive source. An encoder detects a predetermined amount of rotation and signals to restrict the drive roller, while allowing the drive shaft to continue rotating. A main-shaft-angle-detector detects predetermined angles adapted to operate the required stitch pitch and to start counting of pulses at the encoder. When a required number of pulses corresponding to the stitch-pitch is counted, the encoder signals to restrict the drive roller. Thus, the needle thread is positively and intermittently fed according to the stitch pitch.

Abstract: An image generated by the detected signals of a scanning electron microscope is divided, for example, into a plurality of rectangular small areas with the boundaries parallel to the y-axis. The relative height in the boundary is obtained by conducting one dimensional integration for respectively boundaries. Thereafter, the relative height difference between the boundaries is determined by conducting one dimensional integration for each area in the direction perpendicular to the boundary. Thereby, the surface three dimensional topography having less distortion can be measured, even in case errors are included in the normal distribution which indicates the surface topography of the specimen, by adjusting and determining the height in the area by the interporating operation.

Abstract: Disclosed is a method and apparatus for measurement of surface topography of a sample by using a scanning electron microscope, in which: secondary electrons released from the sample are detected by detectors which are four or an integral multiple of four in number and which are disposed above the sample to surround the sample; differential coefficients in two directions perpendicularly intersecting each other at the scanning point are obtained from the detected signals; the differential coefficients are successively summing-integrated along the two directions thereby obtaining surface topography of the sample; and at the same time the calculation expression for calculating the surface topography is corrected with the sample table inclined.

Abstract: An apparatus for improving the signal-to-noise ratio of a scan-type imaging system, in which an image portion which appears virtually periodically or regularly on contiguous scanning lines and a scanning line for which the improvement of signal-to-noise ratio is intended are specified using cursors, the positional differences on the image signal waveforms between the specified scanning line and scanning lines in the specified image portion are detected, and the image signal waveforms in the specified image portion are added by being shifted by the amount of detected positional differences, so that the signal-to-noise ratio of the image signal waveform of the specified scanning line is improved.

Abstract: An image correcting apparatus for correcting distortion appearing in an image produced by electron beam scanning in a SEM under the influence of electric, magnetic and mechanical vibrations through arithmetic operations for eliminating the distortion. Installation of electric shield, magnetic shield and vibration-damping structure is thus rendered unnecessary.

Abstract: A method and system for measuring sectional shape to system the sectional shape of a subject on a plane that includes a direction that couples light sources or detectors, relying upon intensities of the same subject taken or irradiated from one direction wherein a calculation is carried out using a function that is not affected by the change of surface material of the subject in order to find a gradient component of a surface element in the direction which couples the light sources or the detectors, and the sectional shape of the subject on a plane that includes the direction coupling the light sources and the surface element, is determined relying upon the gradient component, making it possible to correctly obtain the sectional shape even when there exist different materials on the subject. Distortion in the measured result caused by the shadow of the surface topography is corrected by repeating the procedure; i.e.

Abstract: To measure a line width of a linear portion of a digital image maintaining a precision finer than a picture element, a digital linear cursor pattern represented by digital picture elements is generated, the pattern is inclined with respect to the horizontal direction by an angle which maximizes the measuring precision, and the pattern is fitted to a linear portion to be measured, to thereby measure the width of a line.

Abstract: A scanning electron microscope for scanning the surface of a specimen with an electron beam to detect secondary electrons, backscattered electrons, or X-rays emitted from the specimen, thereby forming an image of the surface of the specimen, is provided with a specimen table capable of making a horizontal movement, a vertical movement a rotating operation and a tilting operation, an arithmetic unit for converting the output of a detector for detecting the secondary electrons, backscattered electrons or X-ray into a digital signal to store the digital signal, and for calculating the amount of each of the horizontal movement, vertical movement, rotating operation and tilting operation of the specimen table, on the basis of the stored information, an indication given from the outside, and others, and a controller for controlling the specimen table on the basis of a calculated value from the arithmetic unit.

Abstract: Disclosed is an electron beam scanning method and a scanning electron microscope, wherein an electron beam scans an electrical insulation sample in reciprocative directions, with a time difference of n period(s) (n=0, 1, 2, . . . ) plus a half period of a.c. power or external a.c. magnetic field being provided between a scanning start time point in each scanning direction of the deflection magnetic field and a corresponding zero-cross point of the a.c. power or external magnetic field so as to reduce the sample shape measurement error caused by the difference of charging on the sample, thereby enhancing the accuracy of sample shape measurement.

Abstract: Method of determining stereoscopic geometry of an object through photometric stereoscopic measurement with high accuracy. Three or more images of the object picked up in a same fixed direction by varying the state of light sources are derived. Relationships among the images are corrected so that an evaluation function determined by making use of redundancy of the images assumes a minimum value, to thereby prepare a reflectance map to be used in determining orientations of surface elements of the object. Through integration of the orientations, the surface shape of the object is determined. The method is applicable to the image processing in a scanning electron microscope.

Abstract: A sample surface structure measuring method using a scanning type electron microscope featured by scanning the sample surface by an electron beam incident from above the sample surface; measuring the amount of the secondary electrons discharged according to the three-dimensional structure of the sample surface by the scanning; and determining the three-dimensional structure of the sample surface from the amount of the secondary electrons measured based on a relation existing between the predetermined three-dimensional structure and the amount of the secondary electrons discharged.

Abstract: A stereoscopic measuring method and system for measuring the sectional shape of a step formed object such as a semiconductor element carrying a resist and wiring on a wafer. The method and system comprises the steps of means for detecting the images of the step formed object from at least two directions so as to form pictures corresponding to the images detected from different directions, determining the distances D between the upper and lower edges of a step in respective pictures; determining the angles .theta. of inclination of the edge lines with respect to the axis of the pictures, determining the angles of inclination of the standard plane fixed to the step formed object with respect to the viewing directions, and determining, as significant factors of the shape to be determined, the height H and width W of the step formed object.

Abstract: A specimen image display apparatus is disclosed in which a specimen signal generated when the surface of a specimen is radiated while being scanned by an electron beam is detected, and this detection signal is used to display a magnified image of the specimen on a cathode ray tube. In addition to the specimen image, a scale of fixed length which remains unchanged regardless of the magnification of the specimen image and a character indicating converted scale are displayed on the cathode-ray tube, thus improving the accuracy of the measurement of the length of the specimen image on the cathode-ray tube.

Abstract: A beam of electrically charged particles for illuminating a specimen is deflected by a deflection means so that the specimen is scanned with the beam bi-dimensionally. The information signal thus produced by the specimen is detected by a detector means and fed to a display apparatus incorporating therein another deflection means. The information signal is deflected by the latter deflection means to scan the display screen and is displayed thereon as an information image. A wave form of a signal produced in the latter deflection means is detected by a wave form detector means, the output of which is applied to the first mentioned deflection means to thereby deflect the electrically charged particle beam with a signal having a wave form similar to the detected one.