Kabushiki Kaisha Toshiba

Nuflare Technology, Inc.

Susumu Oogi

Takayuki Abe

Takashi Kamikubo

Hitoshi Higurashi

Hirohito Anze

Akihito Anpo

Tomohiro Iijima

Yoshiaki Hattori

Mitsuko Shimizu

Takashi Saito

Toru Tojo

Jun Yashima

Shigehiro Hara

Noriaki Nakayamada

Hideo Inoue

Toshiro Yamamoto

Kazuto Matsuki

Eiji Murakami

Hayato Shibata

A charged particle beam drawing apparatus for drawing patterns corresponding to figures in a drawing data, has a portion for dividing a drawing area on the workpiece into block frames, a portion for combining at least a first block frame and a second block frame into a virtual block frame, and a portion for transferring a data of the virtual block frame from an input data dividing module to a common memory of a first converter and a second converter. The first converter converts a data of a first figure included in the first block frame into a first drawing apparatus internal format data. The second converter converts a data of a second figure included in the second block frame into a second drawing apparatus internal format data. The first figure and the second figure are included in a cell extending over the first block frame and the second block frame.

Charged particle beam drawing method and apparatus

A charged particle beam lithography apparatus includes a first block area divider configured to divide a pattern forming area into a plurality of first block areas in order to make a number of shots when forming a pattern substantially equal; an area density calculator configured to calculate, using a plurality of small areas obtained by virtually dividing the pattern forming area into mesh areas of a predetermined size smaller than all of the first block areas, a pattern area density of each small area positioned therein for each of the first block areas; a second block area divider configured to re-divide the pattern forming area divided into the plurality of first block areas into a plurality of second block areas of a uniform size, which is larger than the small area; a corrected dose calculator configured to calculate, using the pattern area density of each small area, a proximity effect-corrected dose in each corresponding small area positioned inside the second block area for each of the second block areas; a beam dose calculator configured to calculate, using the proximity effect-corrected dose of each small area, a beam dose of a charged particle beam in each corresponding small area; and a pattern generator configured to form a predetermined pattern on a target object by irradiating a charged particle beam of the beam dose calculated for each of the small areas.

Charged particle beam lithography apparatus and charged particle beam lithography method

A pattern writing method acquires the area of a pattern segment located in each of a plurality of small regions obtained by dividing a region on which a pattern is to be written, small region by small region, and writes a pattern based on an optimum dose calculated based on this area. This method employs a scheme of shifting pattern segments and averaging the accumulated area, so that even when the pitch of repetitive patterns slightly differs from the side length of each small region in the pitch direction, a peculiar error does not occur, thereby ensuring highly-precise proximity effect correction and contributing to improving the precision of writing an LSI pattern.

Pattern writing method

A charged beam lithography system includes a charged particle gun for generating charged beams, a main deflecting system and a sub-deflecting system for deflecting the charged beams generated by the charged particle gun, and a control computer. The charged beam lithography system is designed to cause the surface of a substrate to be irradiated with the charged beams from the charged particle gun while continuously moving a stage, to write a desired pattern for each of stripes defined by the maximum deflection widths of the main deflecting system and the sub-deflecting system. The charged beam lithography system further comprises: a real time proximity effect correcting circuit for calculating an optimum dosage for each of the stripes by correcting the dosage of the electron beams in view of the influence of the proximity effect; and a cash memory for storing the optimum dosage data for at least two of the stripes. Thus, the charged beam lithography system is designed to shift a divided form of the whole written region using the stripes at each wiring number of times, by a predetermined distance from a predetermined reference position in a direction perpendicular to a stage continuous moving direction, while selectively extracting the optimum dosage data from the cash memory so as to correspond to each of written stripes at each writing number of times, to write patterns. During the writing operation, the optimum dosage data corresponding to the next region to be written are transferred from the real time proximity effect correcting circuit to the cash memory, and the real time proximity effect correcting circuit calculates optimum dosages for the stripes corresponding to regions to be written after next and thereafter.

Charged beam lithography system

A charged particle beam writing method for determining an optimal exposure dose for each position in a pattern to be drawn on a target before actually drawing the pattern by irradiating the target with charged particles and drawing the pattern with the obtained optimal exposure doses, comprising the first step of determining the first approximate optimal exposure dose for each position on said target, the second step of determining the second optimal exposure dose for each position on said target by determining a corrective value di for correcting said first approximate optimal exposure dose obtained by multiplying the error in the exposure dose of the position produced when exposed to said first approximate optimal exposure dose by a regulation coefficient of a value substantially equal to the exposure dose U(x, y) to back scattering charged particles and adding said corrective value to said first approximate optimal exposure dose, said exposure dose being variable as a function of the location (x, y) of the position, the third step of repeating one of (1) the second step for a predetermined number of times, (2) the second step until each of said second approximate optimal exposure doses tends to converge, and (3) the second step until all the errors in said second approximate optimal exposure doses are found within a predetermined value.

Charged particle beam writing method for determining optimal exposure

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Kawasaki, Japan

Susumu Oogi