Nuflare Technology, Inc.

Kenji Ohtoshi

Osamu Iizuka

Takahito Nakayama

Hitoshi Sunaoshi

Kaoru Tsuruta

Takashi Kamikubo

Shuichi Tamamushi

Rieko Nishimura

Kiyoshi Hattori

Tomohiro Iijima

Taku Yamada

Hayato Kimura

Takayuki Ohnishi

Tomoo Motosugi

Yoshiaki Onimaru

Shunji Shinkawa

Yoshimasa Sanmiya

Tetsuro Nishiyama

Tateki Watanabe

Yasuyuki Taneda

A method of measuring beam positions of multi charged particle beams includes acquiring a number of multi charged particle beams needed for the measurement reproducibility of a current amount to be within the range of an allowable value. The method further includes setting measurement points depending on a desired dimensional accuracy value in an irradiation region irradiated by the whole of the multi charged particle beams, and setting, for each of a plurality of measurement points, a beam region, including a measurement point of measurement points irradiated by a plurality of beams whose number is the number of beams needed for the measurement reproducibility in the multi charged particle beams. Further, the method includes measuring, for each of a plurality of measurement points, the position of a measurement point concerned in a plurality of measurement points by using a plurality of beams of a corresponding beam region.

Method of measuring beam position of multi charged particle beam, and multi charged particle beam writing apparatus

A charged particle beam writing apparatus includes a stage configured to mount a sample placed thereon; an electron optical column including a charged particle gun and deflector, wherein the charged particle gun is configured to emit a charged particle beam, and the deflector includes a plurality of deflecting electrodes configured to control a path of the charged particle beam; an ozone introducing mechanism configured to introduce ozone into the electron optical column; a first voltage supply unit configured to apply a deflection voltage to the plurality of deflecting electrodes to deflect the charged particle beam; and a second voltage supply unit configured to apply an identical negative DC voltage to the plurality of deflecting electrodes, wherein a negative voltage in which the deflection voltage and the negative DC voltage are added is applied to the plurality of deflecting electrodes while the sample is irradiated by the charged particle beam.

Charged particle beam writing apparatus and charged particle beam writing method

According to one aspect of the present invention, a rotation angle measuring method of a multi-charged particle beam image includes two-dimensionally scanning a mark arranged on a stage in a multi-charged particle beam writing apparatus using, among multi-charged particle beams that can be used for exposure, a plurality of representative beams of which number is smaller than the number of beams constituting the multi-charged particle beams, creating a two-dimensional image of the plurality of representative beams based on signals obtained by two-dimensional scanning, and acquiring a rotation angle of the multi-charged particle beam image using the two-dimensional image.

Rotation angle measuring method of multi-charged particle beam image, rotation angle adjustment method of multi-charged particle beam image, and multi-charged particle beam writing apparatus

A charged particle beam writing apparatus includes an emission unit to emit a charged particle beam, a stage to mount thereon a target object to be written, an objective lens to focus the charged particle beam on a surface of the target object, a chamber to house the stage, a measurement unit to measure a partial pressure of a predetermined gas in the chamber in a state where a pressure inside the chamber is controlled to be lower than an atmospheric pressure, and an adjustment unit to adjust a focus position for focusing the charged particle beam on the target object, based on the partial pressure of the predetermined gas.

Charged particle beam writing apparatus, and charged particle beam writing method

A lithography apparatus includes a unit irradiating a charged particle beam; first and second aperture plate members configured to shape the beam; first and second coils configured to be arranged between the unit and the first aperture plate member, to temporarily deflect the beam, to change a direction of the beam after the temporarily deflecting, and to deflect the beam to a position where the beam passes through the first aperture plate member by the changing; a lens configured to be arranged between the first and second aperture plate members and to control a focal position of the beam having passed through the first aperture plate member; and a unit configured to calculate a difference between positions of the beam on the second aperture plate member obtained by different sets of amounts of deflection at a same focal position when a combination of one of focal positions of the beam controlled by the lens and one of sets of amounts of deflection of the beam obtained by the first and second coils is changed.

Lithography apparatus and focusing method for charged particle beam

A focusing method of a charged particle beam includes measuring a first set value to focus a beam on a position of a reference plane by using a lens coil, acquiring a first factor to change a set value of an electrostatic lens depending on a distance and a second factor to change a set value of the coil depending on a distance, measuring a level distribution of a target plane, correcting the first set value by using the second factor to correct a focal point position of the beam in the coil from the position of the reference plane to an intermediate level position of the level distribution of the target plane, and correcting a second set value of the lens depending on a level position of the target plane by using the first factor to correct a focal point position of the beam by the lens.

Focusing method of charged particle beam and astigmatism adjusting method of charged particle

A method of acquiring an offset deflection amount for a shaped beam, includes forming reference images of first and second figures which can be shaped by first and second aperture plates placed on a lithography apparatus, and a reference image of a mark; forming first and second convolution reference images based on the reference images of the mark and of the first and second figures; scanning over the mark with charged particle beams shaped into the first and second figures to acquire optical images of the first and second figures; forming first and second convolution synthesis images based on the first convolution reference image and respectively the optical images of the first and second figures; and calculating an offset deflection amount for the charged particle beam shaped into the second figure to match reference positions of the first and second figures based on center-of-gravity positions of the first and second convolution synthesis images.

Method of acquiring offset deflection amount for shaped beam and lithography apparatus

A method of obtaining a deflection aberration correcting voltage. The method includes writing predetermined patterns at a plurality of focus height positions such that a dose is used as a variable. Dimensional variations of width sizes of the predetermined patterns written at the plurality of focus height positions such that the dose is used as the variable are measured. Further, effective resolutions of the written predetermined patterns are calculated by using the dimensional variations. The method further includes, on the basis of a focus height position at which a minimum effective resolution of the predetermined patterns is obtained, calculating a correcting voltage to correct deflection aberration and outputting the correcting voltage. The correcting voltage is used when a charged particle beam is deflected.

Method of calculating deflection aberration correcting voltage and charged particle beam writing method

A deflector for an equipment of electron beam lithography, the deflector including a plurality of control electrodes arranged symmetrically relative to the center axis of an irradiated electron beam, the electrodes configured to control the electron beam by applying voltages respectively, a plurality of molding substrates arranged symmetrically relative to the center axis of the electron beam configured to face outer peripheral surfaces of the plurality of control electrodes and a plurality of earth electrodes arranged respectively at the plurality of molding substrates. The deflector can suppress generation of cross talks with an improved accuracy of controlling an electron beam.

Deflector for equipment of electron beam lithography and equipment of electron beam lithography

There is provided a charged beam drawing apparatus which includes main/sub two-stage deflectors, divides a main deflection drawing region on a sample into sub deflection drawing regions determined by the deflection width of the sub deflector, selects one of the sub deflection drawing regions by use of the main deflector and draws shots in the selected sub deflection drawing region by use of the sub deflector. A sub deflection driving unit includes a sub deflection sensitivity correction circuit, a sub deflection astigmatic correction circuit, an adder circuit which adds an output of the sub deflection sensitivity correction circuit and an output of the sub deflection astigmatic correction circuit, and a deflection amplifier which additionally applies an output of the adder circuit to the sub deflector.

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Kanagawa, Japan

Kenji Ohtoshi