Patent classifications
H01J2237/216
MULTI CHARGED PARTICLE BEAM ADJUSTMENT METHOD, MULTI CHARGED PARTICLE BEAM IRRADIATION METHOD, AND MULTI CHARGED PARTICLE BEAM IRRADIATION APPARATUS
The present invention quickly calculates values of optimal excitation parameters which are set in lenses in multiple stages. A multi charged particle beam adjustment method includes forming a multi charged particle beam, calculating, for each of lenses in two or more stages disposed corresponding to object lenses in two or more stages, a first rate of change and a second rate of change in response to change in at least an excitation parameter, the first rate of change being a rate of change in a demagnification level of a beam image of the multi charged particle beam, the second rate of change being a rate of change in a rotation level of the beam image, and calculating a first amount of correction to the excitation parameter of each of the lenses based on an amount of correction to the demagnification level and the rotation level of the beam image, the first rate of change, and the second rate of change.
CHARGED PARTICLE BEAM DEVICE, AND METHOD FOR ADJUSTING IMAGE CAPTURING CONDITIONS IN SAID CHARGED PARTICLE BEAM DEVICE
This charged particle beam device comprises: a charged particle beam source that generates charged particle beams; an objective lens in which coil current is inputted to focus the charged particle beams on a sample; a control unit that controls the coil current; a hysteresis characteristics storage unit that stores hysteresis characteristics information of the objective lens; a history information storage unit that stores history information relating to the coil current; and an estimating unit that estimates the magnetic field generated by the objective lens based on the coil current, the history information, and the hysteresis characteristic information, and has a magnetic field correction unit that, when the absolute value of the change amount of the coil current is greater than a prescribed value, further adds to the magnetic field estimated by the estimating unit a correction value according to the coil current and its change amount, correcting the magnetic field generated by the objective lens.
Scanning electron microscope
When a high-performance retarding voltage applying power supply cannot be employed in terms of costs or device miniaturization, it is difficult to sufficiently adjust focus in a high acceleration region within a range of changing an applied voltage, and identify a point at which a focus evaluation value is maximum. To address the above problems, a scanning electron microscope is provided including: an objective lens configured to converge an electron beam emitted from an electron source; a current source configured to supply an excitation current to the objective lens; a negative-voltage applying power supply configured to form a decelerating electric field of the electron beam on a sample; a detector configured to detect charged particles generated when the electron beam is emitted to the sample; and a control device configured to calculate a focus evaluation value from an image formed according to an output of the detector. The control device calculates a focus evaluation value when an applied voltage is changed, determines whether to increase or decrease an excitation current according to an increase or a decrease of the focus evaluation value, and supplies the excitation current based on a result of the determination.
Electron Microscope and Image Generation Method
Provided is an electron microscope for generating a montage image by acquiring images of a plurality of regions in a montage image capturing region set on a specimen, and by connecting the acquired images. The electron microscope includes a specimen surface height calculating unit that calculates a distribution of specimen surface heights in the montage image capturing region by performing curved surface approximation based on the specimen surface heights determined by performing focus adjustment at a plurality of points set in a region including the montage image capturing region, and an image acquiring unit that acquires the images of the plurality of regions based on the calculated distribution of the specimen surface heights.
Optical height detection system
An optical height detection system in a charged particle beam inspection system. The optical height detection system includes a projection unit including a modulated illumination source, a projection grating mask including a projection grating pattern, and a projection optical unit for projecting the projection grating pattern to a sample; and a detection unit including a first detection grating mask including a first detection grating pattern, a second detection grating mask including a second detection grating pattern, and a detection optical system for forming a first grating image from the projection grating pattern onto the first detection grating mask and forming a second grating image from the projection grating pattern onto the second detection grating masks. The first and second detection grating patterns at least partially overlap the first and second grating images, respectively.
PATTERN INSPECTION APPARATUS AND PATTERN INSPECTION METHOD
A pattern inspection apparatus includes a secondary electron image acquisition mechanism to include a deflector deflecting multiple primary electron beams and a detector detecting multiple secondary electron beams, and acquire a secondary electron image corresponding to each of the multiple primary electron beams by scanning a target object with a pattern thereon with the multiple primary electron beams by the deflector, and detecting the multiple secondary electron beams from the target object by the detector, a storage device to store individual correction kernels each generated for individually adjusting a secondary electron image corresponding to each primary electron beam concerning a reference pattern to be commensurate with a reference blurred image, and a correction circuit to correct, by correspondingly using the individual correction kernel, the secondary electron image corresponding to each primary electron beam acquired from the inspection target object.
Method of automatically focusing a charged particle beam on a surface region of a sample, method of calculating a converging set of sharpness values of images of a charged particle beam device and charged particle beam device for imaging a sample
A method of automatically focusing a charged particle beam on a surface region of a sample is provided. The method includes acquiring a plurality of images for a corresponding plurality of focusing strength values; calculating a plurality of sharpness values based on the plurality of images, the plurality of sharpness values are calculated with a sharpness function provided as a sum in a frequency space based on the plurality of images; and determining subsequent focusing strength values of the plurality of focusing strength values with a golden ratio search algorithm based one the calculated sharpness values.
METHOD FOR FOCUSING AND OPERATING A PARTICLE BEAM MICROSCOPE
A method for operating a particle beam microscope comprises setting a distance of an object from an objective lens, setting an excitation of the objective lens, setting an excitation of a double deflector to a first setting such that a particle beam is incident on the object at a first orientation, and recording a first particle-microscopic image at these settings. The method also comprises setting the excitation of the double deflector to a second setting such that the particle beam is incident on the object at a second orientation which differs from the first orientation; and recording a second particle-microscopic image at the second setting of the double deflector. Thereupon, a new distance of the object from the objective lens is determined based on an analysis of the first and second particle-microscopic images, and the distance of the object from the objective lens is set to the new distance.
SCANNING ELECTRON MICROSCOPE DEVICE, SEMICONDUCTOR MANUFACTURING DEVICE, AND METHOD OF CONTROLLING SEMICONDUCTOR MANUFACTURING DEVICE
A scanning electron microscope (SEM) device includes: an electron beam source configured to emit an electron beam; a lens unit disposed between the electron beam source and a stage configured to seat an object including structures having a pattern is seated, and including a scanning coil, the scanning coil configured to generate an electromagnetic field to provide a lens, and an astigmatism adjuster; and a control unit. The control unit is configured to change a working distance between the lens unit and the object to obtain a plurality of original images, obtain a pattern image, in which the structures appear, and a plurality of kernel images, in which a distribution of the electron beam on the object appears, from the plurality of original images, and control the astigmatism adjuster to adjust the focus and the astigmatism of the lens unit using feature values extracted from the plurality of kernel images.
Height measurement device in which optical paths projected on the sample at different incidence angles
The purpose of the present invention is to provide a height measurement device with which, even when the height of a sample surface varies considerably, it is possible, with a relatively simple configuration, to perform height measurement with high accuracy at various heights. In order to achieve the abovementioned purpose, proposed is an optical height measurement device characterized by being provided with: a stage for retaining a sample; a stage driving unit for adjusting the stage at different heights; a projection optical system for projecting light onto the sample; a detection optical system for receiving light reflected from the sample; and a processing unit for measuring the height of the sample on the basis of a signal outputted from the detection optical system, wherein the projection optical system is provided with a light source that emits light, and an optical path dividing element for branching the optical path of the light emitted from the light source, and the detection optical system is provided with a sensor for receiving light reflected from the sample, and an element for adjusting the light path of the light reflected from the sample in the direction of the sensor prior to reception of the light by the sensor.