Fujitsu Corporation

Adv Antest Corporation

Hidefumi Yabara

Hiroshi Yasuda

Isamu Seto

Kiichi Sakamoto

Tomohiko Abe

Takamasa Satoh

Masami Takigawa

Kenichi Miyazawa

Soichiro Arai

Akio Yamada

Yoshihisa Oae

Junichi Kai

Hisayasu Nishino

Takashi Kiuchi

Kenichi Kawakami

Yoshihisa Ooaeh

Hideki Nasuno

Tatsuro Ohkawa

Tomohiro Sakazaki

Akio Takemoto

Atsushi Saito

Nobuyuki Yasutake

Takayuki Nakatani

A D/A converter includes a D/A converter base part having a first D/A converter unit performing D/A conversion of high order bits and a second D/A converter unit performing D/A conversion of low order bits and including an auxiliary bit assigned an identical weight to a least significant bit, a correction D/A converter part, an error detection processing section generating a digital code supplied to a correction D/A converter unit in the correction D/A converter part, and a control section. The control section compares one bit current source with another bit current source in a lower order than the one bit current source, and corrects a value of the one bit current source by causing to supply the digital code to the correction D/A converter unit when the value of the one bit current source changes.

D/A converter and electron beam exposure apparatus

Disclosed is a charged-particle beam lithography apparatus capable of readily detecting an abnormality in controlling the on-off operation of a charged-particle beam. The charged-particle beam lithography apparatus consists of a charged-particle beam generator, a charged-particle beam reshaping unit, a charged-particle beam converging unit, a charged-particle beam deflecting unit, a blanking unit, a digital converting circuit, and a comparing circuit. The blanking unit produces a blanking signal used to control the on-off operation of a charged-particle beam according to exposure pattern data, and thus controls the on-off operation of the charged-particle beam. The digital converting circuit produces a blanking data signal that is a digital signal indicating a variation of the blanking signal. The comparing circuit compares the blanking data signal with the exposure pattern data. It is detected whether the on-off operation of the charged-particle beam is controlled according to the exposure pattern data.

Charged-particle beam lithography apparatus and system capable of readily detecting abnormality in controlling on-off operation

A method of exposing a wafer to a charged-particle beam by directing to the wafer the charged-particle beam deflected by a deflector includes the steps of arranging a plurality of first marks at different heights, focusing the charged-particle beam on each of the first marks by using a focus coil provided above the deflector, obtaining a focus distance for each of the first marks, obtaining deflection-efficiency-correction coefficients for each of the first marks, and using linear functions of the focus distance for approximating the deflection-efficiency-correction coefficients to obtain the deflection-efficiency-correction coefficients for an arbitrary value of the focus distance. A device for carrying out the method is also set forth.

Charged-particle-beam exposure device and charged-particle-beam exposure method

A device exposing a wafer to charged-particle beams in an exposure process generates a plurality of micro beams and controls deflection of each of the micro beams, relative to whether or not the micro beams reach the wafer, in accordance with control data. A data processing unit inserts data-position-adjustment data into the control data for each exposure. A first data-storage unit stores the control data, inserted with the data-position-adjustment data, and outputs the control data at a time of the exposure process. Storage positions of the control data in the first data-storage unit are adjusted by the data-position-adjustment data so that the control data can be continuously read from the first data-storage unit for maintaining a continuous exposure process.

Charged-particle-beam exposure device and method capable of high-speed

Charged-particle-beam exposure device and charged-particle-beam exposure

A method for providing charged particle beam exposure onto an object having a plurality of chip areas with a plurality of aligning marks formed in correspondence to each of said chip areas. A charged particle beam is irradiated upon an object mounted on a mobile step based upon positions of the aligning marks. Actual positions of the alignment marks are detected and compared to the design positions of the alignment marks to determine approximate relationships which are used to calculate an actual position to perform exposure.

Method of providing changed particle beam exposure in which

Adjusting variable delay circuit 311, receiving signal S1, is connected to the input of drive circuit 312. A time point t1, when the output potential of drive circuit 312 traverses reference potential VA between the potential Va of traveling wave V1F of the output potential and 0 V, is detected by comparator 52 for detecting the front edge of V1F, detecting variable delay circuit 50 for delaying signal S1 and D flip-flop 51 for holding the output of comparator 52 at the timing of front edge of the signal outputted from delay circuit 50. A time point t2, when the output potential of drive circuit 312 traverses reference potential VB between the superimposed potential of traveling wave V1F and reflected wave V1B and VA, is detected by comparator 62 for detecting the front edge of V1B, detecting variable delay circuit 60 for delaying signal S1 and D flip-flop 61 for holding the output of comparator 62 at the timing of front edge of the signal outputted from delay circuit 60. The delay time of adjusting variable delay circuit 311 is set so that value {t1+(t2-t1)/2} becomes substantially same as to all the output potentials of drive circuit 31 and so on.

Method and system for changed particle beam exposure

The object of the present invention is to ensure a correct exposure even when a single exposure apparatus is used to expose a predetermined pattern, and an exposure apparatus therefor. According to the present invention, a charged particle beam exposure method, wherein a charged particle beam having a predetermined shape is irradiated to a sample to have the surface of the sample be exposed, comprises the steps of: storing a record of a first quantity of reflected electrons or a first sample current, which is detected in accordance with the charged particle beam irradiatd to the sample when a first exposure pattern is formed in a first area of the sample; and comparing a second quantity of reflected electrons or a second sample current, which is detected in accordance with the charged particle beam irradiated to the sample when the first exposure pattern is formed in a second area of the sample, with the first quantity of the reflected electrons or the first sample current which is stored when the first area is exposed, and generating a matched or unmatched signal therefor.

Charged particle beam exposure method and charged particle beam exposure

To improve in the throughput of an exposure system, the setting time during a step change in the output of an amplifier is reduced by switching resistance between the amplifier and deflector, a glitch waveform generated during a step change in the output of a D/A converter at the preceding stage of the amplifier, is anticipated and is canceled out with a correction waveform, after the output of the D/A converter has settled, this output is sample held and the step change is interpolated at a smoothing circuit, the deflection area is increased by positioning a electrostatic deflector offset around the optical axis relative to another electrostatic deflector, the response speed of the main deflection is improved by adding auxiliary deflection coils of one or two turn, and the alignment time is reduced by combining the coordinate conversion in the wafer area and in the chip area. In order to correct the astigmatism of the electromagnetic lens, two stages of coils are provided and an electric current corresponding to the quantity of deflection is supplied to the coils.

Method of and system for charged particle beam exposure

To improve the throughput of an exposure system, the setting time during a step change in the output of an amplifier is reduced by switching resistance between the amplifier and a deflector. A glitch waveform generated during a step change in the output of a D/A converter at the preceding stage of the amplifier is anticipated and is cancelled out with a correction waveform. After the output of the D/A converter has settled, this output is sample-held and the step change is interpolated with a smoothing circuit. The deflection area is increased by positioning an electrostatic deflector offset around the optical axis relative to another electrostatic deflector, and the response speed of the main deflection is improved by adding auxiliary deflection coils of one or two turns. The alignment time is reduced by combining the coordinate conversion in the wafer area and in the chip area. In order to correct the astigmatism of the electromagnetic lens, two stages of coils are provided and an electric current corresponding to the quantity of deflection is supplied to the coils.

To improve in the throughput of an exposure system, the setting time during a step change in the output of an amplifier is reduced by switching resistance between the amplifier and a deflector, a glitch waveform generated during a step change in the output or a D/A converter at the preceding stage of the amplifier, is anticipated and is canceled out with a correction waveform, after the output of the D/A converter has settled, this output is sample held and the step change is interpolated at a smoothing circuit, the deflection area is increased by positioning a electrostatic deflector offset around the optical axis relative to another electrostatic deflector, the response speed of the main deflection is improved by adding auxiliary deflection coils of one or two turn, and the alignment time is reduced by combining the coordinate conversion in the wafer area and in the chip area. In order to correct the astigmatism of the electromagnetic lens, two stages or coils are provided and an electric current corresponding to the quantity of deflection is supplied to the coils.

A D/A converter converting a digital signal having n bits (n is an integer) into an analog signal includes constant-current output circuits, provided for the n bits of the digital signal, for selectively generating n constant currents on the basis of the n bits of the digital signals. The n constant currents have mutually different current values with respect to the n bits of the digital signal. The constant-current output circuits have resistance elements respectively provided for the n bits of the digital signal. The resistance elements define the mutually different current values. The D/A converter also includes an output circuit for adding the n constant currents to each other and for outputting the analog signal based on an addition result, and a temperature-dependent voltage generating part for generating a temperature-dependent voltage which changes as a temperature around the D/A converter changes. Further, the D/A converter includes a current compensation part for generating a compensation voltage related to at least one of the resistance elements from the temperature-dependent voltage and for applying the compensation voltage to the one of the resistance elements. The compensation voltage compensates for a temperature-dependent variation in a characteristic of the one of the resistance elements.

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Kawasaki, Japan

Hidefumi Yabara