Abstract: An object of the present invention is to provide a charged particle beam apparatus and an alignment method of the charged particle beam apparatus, which make it possible to align an optical axis of a charged particle beam easily even when a state of the charged particle beam changes. The present invention comprises calculation means for calculating a deflection amount of an alignment deflector which performs an axis alignment for an objective lens, a plurality of calculation methods for calculating the deflection amount is memorized in the calculation means, and a selection means for selecting at least one of the calculation methods is provided.

Abstract: An apparatus using charged particle beam is provided with means for detecting positional difference between a target position on a chip pattern within an observation visual field of a microscope after displacing a sample stage thereof and a predetermined position within the visual field, means for storing the detection result and means for determining a new displacement target position for displacement to the predetermined position in subsequent observation while taking into account of the positional difference stored previously and the displacement target position used at the time of storage.

Abstract: The inspection apparatus uses a particle beam and has a high throughput by obtaining a characteristic frequency corresponding to the characteristic quantity of focusing-shift from a Fourier spectrum of a sample image using a focusing-shift evaluator. A beam blur profile is produced corresponding to the characteristic frequency in a beam blur profile generator. A component of the beam-blur profile is removed from the sample image stored in one dimensional image memory using a de-convolution operator. A dimensional measurement is performed in a critical dimension evaluator for an obtained sample image. Since time spent for focus adjustment using particle beam scanning is obviated, it is possible to reduce the inspection time for a dimension and an appearance abnormality of a semiconductor element.

Abstract: The inspection apparatus uses a particle beam and has a high throughput by obtaining a characteristic frequency corresponding to the characteristic quantity of focusing-shift from a Fourier spectrum of a sample image using a focusing-shift evaluator. A beam blur profile is produced corresponding to the characteristic frequency in a beam blur profile generator. A component of the beam-blur profile is removed from the sample image stored in one dimensional image memory using a de-convolution operator. A dimensional measurement is performed in a critical dimension evaluator for an obtained sample image. Since time spent for focus adjustment using particle beam scanning is obviated, it is possible to reduce the inspection time for a dimension and an appearance abnormality of a semiconductor element.

Abstract: An electron beam which can transmit through part of a specimen and can reach a portion not exposing to the electron beam is irradiated and a scanning image is obtained on the basis of a signal secondarily generated from a portion irradiated with the electron beam. Dimension-measuring start and end points are set on the scanning image and a dimension therebetween is measured. A cubic model is assumed, the cubic model is modified so as to match the scanning image, and dimension measurement is carried out on the basis of a modified cubic model.

Abstract: An electron beam which can transmit through part of a specimen and can reach a portion not exposing to the electron beam is irradiated and a scanning image is obtained on the basis of a signal secondarily generated from a portion irradiated with the electron beam. Dimension-measuring start and end points are set on the scanning image and a dimension therebetween is measured. A cubic model is assumed, the cubic model is modified so as to match the scanning image, and dimension measurement is carried out on the basis of a modified cubic model.

Abstract: In the electron microscope, a degree of sample contamination caused by irradiating electron beams to a sample can be suppressed to an allowable range. The electron microscope is comprised of: means for directly measuring an electron beam irradiation current to a sample; time measuring means for measuring irradiation time of electron beams to an observation region on the sample; and means for calculating a dose of the electron beams irradiated to the observation region based upon the measured electron beam irradiation current, the measured electron beam irradiation time, and preset observation magnification.

Abstract: An electron beam which can transmit through part of a specimen and can reach a portion not exposing to the electron beam is irradiated and a scanning image is obtained on the basis of a signal secondarily generated from a portion irradiated with the electron beam. Dimension-measuring start and end points are set on the scanning image and a dimension therebetween is measured. A cubic model is assumed, the cubic model is modified so as to match the scanning image, and dimension measurement is carried out on the basis of a modified cubic model.

Abstract: An electron beam is focused on a specimen by a focusing lens. A light beam is incident on the position of irradiation of the specimen with the electron beam and the reflected light beam is detected by a linear light detector. The output of the detector is used to measure the height of the specimen at the position of irradiation of the electron beam. The specimen is moved in a plane perpendicular to an optical axis of the focusing lens. A specimen height measuring device carries out the height measurement of the specimen at a position to be observed on the specimen and at positions thereon which are in the vicinity of the position to be observed, when those positions are located at the position of irradiation of the electron beam. The specimen height measuring device averages the measured values so as to produce a focusing correction signal on the basis thereof and controls the focusing lens on the basis of the focusing correction signal.

Abstract: An electron beam apparatus focusses an electron beam onto a specimen by means of an objective magnetic lens. In order to detect changes in the height of the specimen, a laser light beam from a laser source is incident on the specimen and the reflected laser beam is detected by a light detector. Any change in the height of the specimen changes the path of the laser beam to the detector. Therefore, by monitoring the detector, the focussing of the electron beam on the specimen can be controlled by varying the current to an excitation coil of the objective magnetic lens or by moving the specimen via a mounting stage. At least one of the pole pieces of the objective lens is on the opposite side of the path of the laser beam to the source of the electron beam, so that the objective magnetic lens may be close to the specimen, permitting a short focal length. Thus, the laser beam may pass between the pole pieces. An optical microscope may also be provided to permit the specimen to be viewed.

Abstract: An electron beam, which can transmit through part of a specimen and can reach a portion that is not exposed to the electron beam, is irradiated, and a scanning image is obtained on the basis of a signal secondarily generated from a portion irradiated with the electron beam. Dimension-measuring start and end points are set on the scanning image and a dimension therebetween is measured. A three-dimensional model is assumed, the three-dimensional model is modified so as to match the scanning image, and dimension measurement is carried out on the basis of a modified three-dimensional model.

Abstract: When an image display unit displays a magnified image of an object being examined, a measuring unit automatically computes the dimensions of the image at the preset position. A tolerance range setting unit has been supplied with an upper and a lower limit value according to which it can judge the dimensions of the object at the preset position to be normal, whereas a comparison-decision unit decides that the dimensions thus computed are held between the upper and lower limit values. When the measured result is found outside the range of upper to lower limit values, the right-or-wrong decision data is stored in a memory and is redisplayed in the form of an image by the image display unit at proper timing.

Abstract: A charged particle beam apparatus includes a charged particle beam generating system for causing a charged particle source to generate a charged particle beam. A focusing system focuses the charged particle beam onto a sample. A deflecting system causes the focused charged particle beam to scan the surface of the sample. An evacuating system evacuates a space through which the charged particle beam passes. A detector detects information obtained by irradiating the charged particle beam onto the sample. An image display system displays as an image the status of distribution of the information over the sample surface based on a detection signal forwarded from the detector. The focusing system is entirely constituted by an electrostatic lens containing a plurality of lens electrodes, one of the lens electrodes being a final electrode located closest to the sample.

Abstract: A technique for displaying a scanned specimen image permits non-destructive observation of a surface structure having large or precipitous unevenness, an internal structure of a specimen or a specific structure of a defect or foreign matter, which non-destructive observation has hitherto been considered to be difficult to achieve. The technique can be applied to inspection and measurement so as to economically provide devices and parts of high quality and high reliability. Thus, secondary information such as secondary electrons resulting from interaction of primary information with a specimen, the primary information being generated as a result of interaction of a scanning electron beam with the specimen, is utilized as an image signal to form an image.

Abstract: An electron beam apparatus comprises an electron beam source, a unit for irradiating an electron beam on a specimen, a detector for secondary electrons, an electrode for generating an electric field sufficient to draw out secondary electrons in a recess in the specimen from the recess, and a unit for generating a magnetic field for focusing secondary electrons drawn out of the recess. With this construction, the secondary electrons drawn out of the recess by the electric field reach the detector without being attracted by the electrode. By adopting this construction, a contact hole of high aspect ratio formed in a semiconductor device and having a small diameter and a large depth can be observed.

Abstract: In a scanning electron microscope with such a structure that a retarding static field for an electron beam is produced between an objective lens and a sample, when the following three conditions can be satisfied, a switch for applying a superimposed voltage is closed to apply the superimposed voltage to the sample. In the first condition, a switch for applying an acceleration voltage is closed and the acceleration voltage 5 is applied. In the second condition, both of a valve and a valve are opened which are provided between a cathode and the sample. In the third condition, when the sample is mounted on a sample stage by a sample replacing mechanism 57, a valve through which the sample passes is closed. The sample stage is electrically connected via a discharge resistor to a sample holder, and when the switch is opened, electric charges charged on the sample are discharged through the sample holder and the sample stage.

Abstract: Provided between an optical axis of a primary electron beam directed to a specimen and a secondary electron detector for detecting secondary electrons emitted from the specimen is a shielding electrode which has a transparency for secondary electrons and has a shielding effect for an attracting electric field produced by the secondary electron detector. An opposed electrode is provided at a position facing the shielding electrode with the optical path of the electron beam disposed therebetween. Applied across the shielding electrode and the opposed electrode is a voltage which produces a deflecting electric field along the electron beam path in the vicinity of the secondary electron detector. The deflecting electric field deflects the secondary electrons to the shielding electrode side so that they pass therethrough before they are captured by the secondary electron detector.

Abstract: Improvements in a charged particle beam apparatus are contemplated and especially a column structure incorporating a superhigh vacuum evacuation system is provided which is reduced in size and weight and has high performance. In order to evacuate surrounding space of a charged particle source to superhigh vacuum, ion pumps are built in a vacuum enclosure of a column. Each ion pump includes a magnet unit 15, a yoke and an electrode, and the magnet unit per se is built in the vacuum enclosure. A charged particle beam focusing optics for focusing and deflecting a charged particle beam from the charged particle beam source is arranged in a space which is defined interiorly of the yoke. The column structure can be reduced in size and weight and a charged particle beam apparatus having high performance can be obtained.

Abstract: A scanning microscope, such as a scanning electron microscope, has an energy beam which is caused to scan on a sample. A detector detects the interaction of the beam with the sample and generates sample image signals which are used to generate a display image of the scanned part of the sample. The sample image signals may be stored in an image memory, and a part of those sample image signals are read to generate the display image. This permits an effective magnification to be achieved without scanning the sample with scanning lines which are too close. Alternatively, or in addition, the beam may be cut intermittently during the scanning, at least for magnification above a predetermined limit. Where scanning is in a series of frames, each formed of a series of scanning lines, such cutting may change the interval between frames, the interval between lines, or may cause intermittent cutting within a line.

Abstract: A charged particle beam apparatus includes a charged particle beam generating system for causing a charged particle source to generate a charged particle beam. A focusing system focuses the charged particle beam onto a sample. A deflecting system causes the focused charged particle beam to scan the surface of the sample. An evacuating system evacuates a space through which the charged particle beam passes. A detector detects information obtained by irradiating the charged particle beam onto the sample. An image display system displays as an image the status of distribution of the information over the sample surface based on a detection signal forwarded from the detector. The focusing system is entirely constituted by an electrostatic lens containing a plurality of lens electrodes, one of the lens electrodes being a final electrode located closest to the sample.