WO2010014111A1

WO2010014111A1 - Electron beam recording apparatus, and control apparatus and control method for same

Info

Publication number: WO2010014111A1
Application number: PCT/US2008/071926
Authority: WO
Inventors: Hiroaki Suzuki; Akio Fukushima; Takayuki Kasuya; Douglas Marshal Carson
Original assignee: Pioneer Corporation; Pioneer Fa Corporation
Priority date: 2008-08-01
Filing date: 2008-08-01
Publication date: 2010-02-04

Abstract

The present invention comprises a synchronization signal generator for generating a rotation synchronization signal and a translation synchronization signal to produce an operation clock for rotationally driving and translationally driving the substrate; a deflection signal generator for generating a deflection signal for deflecting the electron beam in synchronism with the translation synchronization signal to overwrite the data so that a beam spot of the electron beam is at the same speed and in the same direction as translation of the substrate through a period in which the substrate is rotated a prescribed number of overwriting cycles in synchronism with the rotation synchronization signal; and a data output section for outputting concentric circle pattern data in accordance with the number of overwriting cycles in synchronism with the rotation synchronization signal.

Description

DESCRIPTION ELECTRON BEAM RECORDING APPARATUS, AND CONTROL APPARATUS

AND CONTROL METHOD FOR SAME

TECHNICAL FIELD

The present invention relates to an electron beam recording apparatus for manufacturing an original recording, and to a control apparatus and control method for the electron beam recording apparatus.

BACKGROUND ART

Magnetic disks or hard disks (HD) are used in the recording apparatuses of personal computers (PC), and in mobile devices, car-mounted devices, and the like. The range of applications of such disks has significantly expanded in recent years, and the surface recording density thereof is also rapidly increasing.

Electron beam mastering techniques are being widely researched for the manufacture of such high-recording-density hard disks. In an electron beam lithography exposure apparatus, an electron beam spot emitted from an electron gun and focused by an electron lens is radiated onto a substrate on which a resist is applied. The radiation position of the electron beam spot is controlled by a blanking control system and a beam deflection control system, and the desired beam pattern is drawn. For example, apparatus for creating an original recording on an optical disk or other recording medium with high precision have been developed as electron beam exposure apparatus. An example is disclosed in Japanese Laid-open Patent Application No. H06-131706.

Therefore, in order to perform high-recording-density drawing with an electron beam, the radiation position of the electron beam spot must be controlled with high precision. In hard disks, a concentric circular pattern is used rather than the spiral pattern employed in optical disks and the like. It is important that an electron beam recording apparatus be developed that has excellent control properties, and that is capable of high-precision drawing in a concentric circle pattern when drawing is performed with an electron beam in a concentric circle pattern. There is also a need for a control apparatus and control method for an electron beam recording apparatus capable of control with high precision and a high degree of freedom.

DISCLOSURE OF THE INVENTION An example of an object of the present invention is to provide an electron beam recording apparatus that is capable of drawing in a concentric circle pattern with high precision and that has a high degree of freedom and excellent control properties, to provide a control apparatus and control method for the same, and to provide a computer program. The control apparatus according to the present invention is a control apparatus for an electron beam recording apparatus for translationally moving a substrate in a radial direction of the substrate while rotating the substrate, and radiating an electron beam while deflecting the beam for drawing a concentric circle pattern on the substrate; characterized in comprising: a synchronization signal generator for generating a rotation synchronization signal and a translation synchronization signal to produce an operation clock for rotationally driving and translationally driving the substrate; a deflection signal generator for generating a deflection signal for deflecting the electron beam in synchronism with the translation synchronization signal to overwrite the concentric circle pattern so that a beam spot of the electron beam is at the same speed and in the same direction as translation of the substrate through a period in which the substrate is rotated a prescribed number of overwriting cycles in synchronism with the rotation synchronization signal; and a data output section for outputting the concentric circle pattern data in accordance with the number of overwriting cycles in synchronism with the rotation synchronization signal.

The computer program product comprising a computer useable medium having computer useable program code for performing drawing control of an electron beam recording apparatus for radiating an electron beam on a substrate while rotating and translationally moving the substrate; characterized in comprising the steps of: computer useable program code for generating a rotation clock and a translation clock for indicating drive amounts of rotational driving and translational driving of the substrate; computer useable program code computing a deflection amount of the electron beam on the basis of the translation clock so that a radiation position of the electron beam moves at the same speed and in the same direction as translation of the substrate through a period in which the substrate is rotated a prescribed number of times in accordance with the rotation clock; and computer useable program code issuing an output command for outputting a pattern data in accordance with the prescribed number of times in accordance with the rotation clock.

The electron beam recording apparatus according to the present invention is an electron beam recording apparatus for translationally moving a substrate in a radial direction of the substrate while rotating the substrate, and radiating an electron beam while deflecting the beam for drawing a concentric circle pattern on the substrate; the electron beam recording apparatus characterized in comprising: a control section having a synchronization signal generator for generating a rotation synchronization signal and a translation synchronization signal to produce an operation clock for rotationally driving and translationally driving the substrate, a deflection signal generator for generating a deflection signal for deflecting the electron beam in synchronism with the translation synchronization signal to overwrite the concentric circle pattern so that a beam spot of the electron beam is at the same speed and in the same direction as translation of the substrate through a period in which the substrate is rotated a prescribed number of overwriting cycles in synchronism with the rotation synchronization signal, and a data output section for outputting the concentric circle pattern data in accordance with the number of overwriting cycles in synchronism with the rotation synchronization signal; a rotation/translation drive section for rotationally driving and translationally driving the substrate in synchronism with the rotation synchronization signal and translation synchronization signal; an electron beam deflector for deflecting the electron beam in accordance with the deflection signal; and an electron beam modulator for performing drawing with the electron beam in accordance with the concentric circle data outputted from the data output section.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic block diagram showing the structure of the electron beam recording apparatus (EBR) that is Example 1 of the present invention;

FIG. 2 is a schematic block diagram showing the structure of the formatter shown in FIG. 1 ;

FIG. 3 is a diagram showing the drawing sequence performed by the EBR according to the control of the formatter;

FIG. 4 is a diagram showing the relationship between the rotational speed (REV) of the substrate, and the electron beam deflection signal F3 after the time (Tini) at which drawing is initiated;

FIG. 5 is a diagram showing the deflection control of the electron beam with respect to the translational movement of the substrate;

FIG. 6 is a diagram showing the upper surface of the substrate, and shows the deflection control of the formatter for overwrite-drawing the track TRl in which a spiral beam track (dashed line) is drawn as a concentric-circle beam track (solid line); FIG. 7 is a diagram like FIG. 5, and shows the deflection control of the electron beam with respect to the translational movement of the substrate when the track TR2 is furthermore drawn after the track TRl is drawn;

FIG. 8 is a diagram like FIG. 6, and shows a case in which the concentric- circle track TR2 is furthermore overwrite-drawn after the concentric-circle track TRl is overwrite-drawn; and FIG. 9 is a schematic diagram showing the track pitch and dose amount by overwriting of the tracks TRl and TR2.

FIG. 10 is a schematic block diagram showing the structure of the electron beam recording apparatus according to another example of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION Examples of the present invention will be described in detail with reference to the drawings. In the examples described below, the same reference symbols are used to indicate equivalent constituent elements. FIG. 1 is a schematic block diagram showing the structure of the electron beam recording apparatus (EBR; referred to as EBR hereinafter) 10 and the EBR control apparatus (formatter) 50 for controlling the EBR 10 according to Example 1 of the present invention. The electron beam recording apparatus 10 is an EB mastering apparatus for using an electron beam to create an original recording used for magnetic disk manufacturing, for example. The EBR control apparatus (formatter) 50 may be built into the EBR 10 and configured for overall functioning as an electron beam recording apparatus (EBR) 10. An example of a case will be described hereinafter in which the EBR control apparatus (also referred to as simply the "formatter" hereinafter) and the EBR 10 are connected to each other by an interface circuit. Structure of the electron beam recording apparatus (EBR) 10

The EBR 10 is provided with a vacuum chamber 11; a stage driving apparatus for driving the mounting, rotation, and translation of a substrate placed within the vacuum chamber 11 ; an electron beam column 20 attached to the vacuum chamber 11 ; and various circuits and control systems for performing beam control, control of the stage driving apparatus, and other functions.

More specifically, a substrate 15 used for a master disc and/or a mold (stamper) for a hard disc medium original recording is mounted on a turntable 16. The substrate 15 is a silicon and/or glass substrate with resist rosin, which is photosensitive to an electron beam, applied on its surface. The turntable 16 is rotationally driven in relation to the axis (Z axis) perpendicular to the principal surface of the disk substrate by a spindle motor 17 that is a rotational driving apparatus for rotationally driving the substrate 15. The spindle motor 17 is provided on a translation stage (also referred to simply as a stage hereinafter) 18. The stage 18 is attached to a translation motor 19 that is a transferring (translational driving) apparatus, and is configured so as to be able to move the spindle motor 17 and the turntable 16 in a prescribed direction in a plane parallel to the principal surface of the substrate 15. The turntable 16 is composed of a dielectric, e.g., a ceramic, and has an electrostatic chucking mechanism (not shown). The electrostatic chucking mechanism comprises the turntable 16 and an electrode composed of a conductor provided inside the turntable 16 for causing electrostatic polarization. A high- voltage power supply (not shown) is connected to the electrode, and the substrate 15 is held in place by application of a voltage to the electrode from the high-voltage power supply.

A reflecting mirror 35 A, an interferometer, and other optical elements that are portions of a laser position measurement system 35 described hereinafter are provided on the stage 18.

The vacuum chamber 11 is provided via an air damper or other vibration isolation system (not shown), and transmission of vibration from the outside is suppressed. A vacuum pump (not shown) is connected to the vacuum chamber 11 , whereby the inside of the chamber is evacuated, and the inside of the vacuum chamber 11 is thereby set so as to be a vacuum atmosphere having a prescribed pressure.

An electron gun (emitter) 21 for emitting an electron beam, a converging lens

22, a blanking electrode 23, an aperture 24, a beam deflection coil 25, an alignment coil 26, a deflection electrode 27, a focus lens 28, and an objective lens 29 are arranged in sequence inside the electron beam column 20. The electron gun 21 emits an electron beam (EB) that is accelerated to some tens of KeV by a negative electrode (not shown) to which a high voltage fed from an acceleration high- voltage power supply (not shown) is applied. The converging lens 22 converges the emitted electron beam. The blanking electrode 23 switches the electron beam on or off (ON/OFF) on the basis of a modulation signal from a blanking control section 31. Specifically, a voltage is applied across the blanking electrode

23, and the electron beam passing through is significantly deflected, whereby the electron beam can be prevented from passing through the aperture 24, and radiation of the electron beam to the substrate 15 can be turned off (non-radiation).

The alignment coil 26 corrects the position of the electron beam on the basis of a correction signal from a beam position correction device 32. The deflection electrode 27 performs deflection control of the electron beam at high speed on the basis of a control signal from a deflection control section 33. The position of the electron beam spot in relation to the substrate 15 is controlled by this deflection control. The focus lens 28 controls the focus of the electron beam on the basis of a control signal from a focus control section 34.

A light source 36A and a photodetector 36B for detecting the height of the principal surface of the substrate 15 are provided to the vacuum chamber 11. The photodetector 36B includes, for example, a position sensor, a CCD (Charge Coupled Device), or the like; receives a light beam (laser beam) emitted by the light source 36A and reflected by the surface of the substrate 15; and feeds the photoreception signal to a height detection section 36. The height detection section 36 detects the height of the principal surface of the substrate 15 on the basis of the photoreception signal and generates a detection signal. The detection signal indicating the height of the principal surface of the substrate 15 is fed to the focus control section 34, and the focus control section 34 adjusts the focus of the electron beam on the basis of the detection signal. The laser position measurement system 35 uses a laser light for measurement from a light source inside the laser position measurement system 35 to measure the distance to the stage 18, and sends the measurement data, i.e., the position data of the stage 18, to a translation controller 37.

The translation controller 37 performs X stage translation control in synchronism with a translation clock signal (T-CLK) F4 that is a reference signal fed from the formatter 50. The translation controller 37 generates a translation error signal on the basis of the stage position data from the laser position measurement system 35, and transmits the translation error signal to the beam position correction device 32. As described above, the beam position correction device 32 corrects the electron beam position on the basis of the translation error signal. The translation controller 37 generates a control signal for controlling the translation motor 19, and feeds the control signal to the translation motor 19.

A rotation controller 38 controls the rotation of the spindle motor 17 in synchronism with a rotation clock signal (R-CLK) F5 that is a reference signal fed from the formatter 50. More specifically, a rotary encoder (not shown) is provided to the spindle motor 17, and a rotation signal is generated when the turntable 16 (i.e., the substrate 15) is rotated by the spindle motor 17. The rotation signal includes an origin signal indicating a reference rotation position of the substrate 15, and a pulse signal (rotary encoder signal) for each prescribed angular amount of rotation from the reference rotation position. The rotation signal is fed to the rotation controller 38. The rotation controller 38 detects a rotation error of the turntable 16 through the use of the rotary encoder signal, and corrects the rotation of the spindle motor 17 on the basis of the detected rotation error.

Various control signals are fed to an EBR interface circuit (EBR I/F) 39 via a formatter interface circuit 54 of the EBR control apparatus 50. More specifically, a modulation signal Fl and a deflection signal F3 are fed from the EBR control apparatus 50. The blanking control section 31 performs blanking control (on/off switching of the electron beam) on the basis of the modulation signal Fl, and the deflection control section 33 performs deflection control of the electron beam on the basis of the deflection signal F3. The control signal from the EBR control apparatus 50, and the operation of the EBR control apparatus 50 on the basis of the control signal will be described in detail below. Structure of the formatter 50

The formatter 50, which is the control apparatus for the EBR 10, will next be described in detail with reference to FIG. 2. The formatter 50 has a control signal generator (processor) 51 for generating a control signal for controlling the EBR 10; and a formatter interface circuit (formatter I/F) 54. Specifically, the control signal, control data, and the like generated by the control signal generator 51 (*1) are transmitted to the EBR 10 via the formatter interface circuit 54.

The formatter 50 is also provided with a clock signal generator 52 for generating various clock signals described hereinafter. The clock signal generator 52 generates clock signals in accordance with a CLV (Constant Linear Velocity) drawing or a CAV (Constant Angular Velocity) drawing, for example. In other words, the clock signal generator 52 generates rotation clock and translation clock signals that indicate the amounts of driving of the spindle motor 17 and the translation motor 19, as described in detail hereinafter. The formatter 50 also has memory 53 for storing data or setting values relating to the various control signals described hereinafter, and an input/output section 55 for inputting and outputting setting values and the like that are used for control of the EBR 10. Furthermore, the formatter 50 is provided with a display section 56 for displaying the operating conditions, operating state, setting values, and the like of the EBR 10 and the formatter 50. For example, the memory 53 stores data for drawing patterns of a discrete track medium and/or a bit pattern medium for a hard disc drive (such as concentric patterns, patterns for track and servo areas). The control signal generator 51 generates a signal to control EBR 10 by utilizing these data stored in the memory 53.

The various control signals (interface signals) used for controlling the EBR 10 between the formatter interface circuit (formatter I/F) 54 and the EBR interface circuit (EBR I/F) 39 provided to the EBR 10 are as described below.

[Fl -modulation signal (Fl -Modulation (/Blanking))]: also referred to hereinafter as the modulation signal Fl.

Fl is a signal outputted by the formatter for turning the electron beam on and off. For example, blanking of the electron beam is performed when the signal is "Low," and the electron beam is turned off.

[F3-sawtooth-waveform deflection signal (F3-Sawtooth-Deflection-X)]: also referred to hereinafter as the saw-toothed deflection signal F3, or simply the deflection signal F3.

F3 is a deflection signal for making a spiral into concentric circles. The polarity of a sawtooth wave must be inverted according to the X stage movement direction.

[F4-translation clock signal (F4-Translation clock)]: also referred to hereinafter as the translation clock signal F4, or simply the translation clock F4.

F4 is a reference signal outputted by the formatter to the X stage. The EBR apparatus drives the translation stage (X stage) in synchronism with this signal. A pulse reference unit (ΔX) can be set on the formatter side. The default value is

632.991345/1024 nm, for example. Values for ΔX/2, ΔX/4, ΔX/8, and so forth can also be set.

[F5-rotation clock signal (F5-Rotation clock)]: also referred to hereinafter as the rotation clock signal F5.

F5 is a reference signal outputted by the formatter to the rotation spindle. The default value is 3600 pulse/rev, for example. The duty is 50%, for example. [F6-starting signal (F6-/Start)]: also referred to hereinafter as the draw starting signal F6, or simply the starting signal F6.

After the draw end signal F7 (described below) is "High," and the translation clock signal F4 and rotation clock signal F5 are in effect, the EBR apparatus side synchronizes with these clocks, and the EBR apparatus side sets the draw starting signal F6 to "Low" at the time the draw starting radius is reached. The formatter thereby initiates drawing (signal output).

[F7-end signal (F7-End)]: also referred to hereinafter as the draw end signal F7, or simply the end signal F7. F7 is "High" when drawing (signal output) by the formatter is completed, and the EBR apparatus is notified. F7 is "Low" while the translation clock signal F4 and the rotation clock signal F5 are in effect. The EBR apparatus receiving this signal sets the draw starting signal F6 to "High," and drawing of the current job is ended.

The signals described above are the main interface signals, but the numerical values, logical levels ("High," "Low"), and the like described above are merely examples, and can be appropriately set and modified. Operation of the EBR 10 and the formatter 50

The operation of the EBR 10 and the EBR control apparatus 50 will next be described. FIG. 3 is a diagram showing the drawing sequence performed by the EBR 10 according to the control of the formatter 50.

Prior to starting a job for drawing, the formatter 50 sets the draw end signal F7

(F7-End) to "Low," and outputs the translation clock signal F4 and rotation clock signal F5 (time Tp in FIG. 3). The translation clock signal F4 and rotation clock signal F5 at this time are clock signals of the frequency (Fini) at the time of draw job initiation.

After the above mentioned translation clock signal F4 and rotation clock signal F5 have become effective (signal output), the EBR 10 operates in synchronism with these clocks, and the EBR 10 sets the draw starting signal F6 (F6-/Start) to "Low" (active) at the time when the draw starting radius is reached. The formatter 50 starts drawing in response to the rotation clock signal F5 becoming active. Specifically, outputting of the modulation signal Fl that is the draw signal is started (time Tini in FIG. 3). The control operation of the formatter 50 at the time of drawing will next be described with reference to the drawings. The EBR 10 draws concentric circular tracks through the control of the formatter 50, but N cycles (N is any natural number) of drawing (overwriting) are performed in one track. The present example is of a case in which the EBR 10 performs three (N = 3) overwriting cycles for each track.

FIG. 4 shows the relationship between the rotational speed (REV) of the substrate 15, and the electron beam deflection signal F3 after the time (Tini) at which drawing is initiated. The deflection signal F3 in this case is a saw-toothed signal (analog voltage signal), and linearly changes from the reference voltage (in this example, V = Vref = 0 Volt) to V = 3* VD (i.e., VD per rotation) in the time taken for the substrate 15 to rotate three times (Tini to T3). When the deflection signal F3 is the reference voltage Vref, the electron beam is in the reference deflection position (e.g., perpendicular to the substrate 15).

As shown in FIG. 5, the substrate 15 moves translationally from the position (indicated by the dashed line; substrate center indicated by O) at the start of drawing

(indicated by the solid line; substrate center indicated by O¹) at the end of three rotations. The beam is then deflected according to the deflection signal F3 so that the electron beam EB follows the substrate 15. hi other words, when the deflection

(i.e., emission direction) of the electron beam EB is fixed, a spiral beam track (indicated by the dashed line) is formed on the substrate 15, but the EBR 10 draws a concentric circular track TRl (indicated by the solid line) through the control

(deflection signal F3) of the formatter 50, as shown in FIG. 6.

The formatter 50 controls deflection of the electron beam on the basis of the drive amount and number of pulses indicated by the rotation clock signal F5 and translation clock signal F4 so that the beam spot is in the same radius position and angle position (r, θ) in relation to the center of the substrate 15 (so that the beam spot follows the substrate 15).

In each of the first through third rotations (REV = 1 through 3) of the substrate 15, the same data (modulation signal Fl) are outputted from the formatter 50, whereby the track TRl is drawn three times (N = 3) by overwriting the same data.

In other words, the beam spot of the electron beam EB is deflected so as to be in the same direction and at the same speed as the translation of the substrate 15. Through this beam deflection control, the beam spot of the electron beam EB on the substrate 15 is fixed in the same radius position and angle position (r, θ) in relation to the center of the substrate 15, and the concentric circular track TRl (first track) is therefore overwritten and drawn. Any number of overwriting cycles can be set by a setting value file input and the like from an input/output section 55. And, in response to a setting number of overwritten, the translation distance while the substrate 15 makes one revolution is adjusted. For example, if overwritten is set to three, the translation distance while the substrate makes one revolution is set to 1/3 of the track pitch. Since a necessary overwritten number differs depending upon resist material applied on a substrate and/or time applied in developing process and so on, it is possible to deal with the process flexibly in manufacturing a master by setting the overwritten number arbitrarily.

As shown in FIG. 9, the dose amount of the track TRl can be increased to three times that of a case in which overwriting is not performed (N = 1), noise or random components during drawing can be removed, and drawing can be performed with a high S/N ratio and high precision.

At the ending time (T = T3) of overwrite-drawing of the first track TRl, the deflection voltage is instantly returned to the reference voltage (V = Vref = 0 Volt; FIG. 4) by the deflection signal F3. Specifically, the electron beam is returned to the reference deflection position (e.g., perpendicular to the substrate 15), and the beam spot of the electron beam EB is returned to substantially the same angle position as the angle position in relation to the center of the substrate 15 at the time when drawing of the track TRl is ended. At this time, the radius position (radial position) of the beam spot on the substrate 15 in relation to the center of the substrate 15 is moved an amount commensurate with the translational distance required for overwriting of the track TRl . As shown in FIG. 9, this distance is the pitch between tracks (referred to as the track pitch).

In the fourth through sixth rotations of the substrate 15 (REV = 4 through 6), the same beam deflection control as described above is performed. A concentric circular second track TR2 at a distance equal to the above mentioned track pitch is overwrite-drawn by the control of the formatter 50 (FIGS. 7 through 9). Beam deflection control through control of the formatter 50 as described above is repeatedly executed, and overwrite-drawing of the first track TRl, the second track TR2, a third track TR3, . . . is performed (FIG. 3).

This beam deflection control can be applied to CLV (Constant Linear Velocity) drawing, CAV (Constant Angular Velocity) drawing, and other various drawing modes.

The sawtooth deflection signal F3 described above is appropriately selected according to the drawing mode (CLV, CAV, or the like). Specifically, the slope of the sawtooth deflection signal (analog voltage signal) F3 that corresponds to each of the first track TRl, the second track TR2, . . . is selected according to the drawing mode. The radiation position of the electron beam may be changed so as to follow the translational movement of the substrate 15.

When drawing of the set job is ended, the formatter 50 sets the draw end signal F7 (described hereinafter) to "High," and notifies the EBR 10 of draw completion (T = Tend; FIG. 3). After this signal is received, the EBR 10 sets the draw starting signal F6 to "High," and drawing of the current job is ended. The substrate 15, after necessary patterns are drawn and the resist applied thereon will be put into exposure, etching process, etc. and a mold, such as for example, a stamper of a hard disc medium, will be made. Consequently, by overwrite-drawing concentric circular tracks according to the present invention, random components in the drawing of each track can be removed, and drawing can be performed with a high S/N ratio and high precision.

The control performed by the formatter 50 as described above can also be implemented as a computer program. Specifically, it is possible to use a computer program that includes commands or code for issuing the modulation signal Fl, the deflection signal F3, the translation clock signal F4, the rotation clock signal F5, the draw starting signal F6, the draw end signal F7, and other signals described above as control signals. The computer program can be executed by a processor, and the above mentioned control signals can be generated to control an electron beam recording apparatus. FIG. 10 is a schematic block diagram showing the structure of the electron beam recording apparatus according to another example of the present invention. The same numbers are used for the same structural elements as in Fig. 1.

In this example, the deflection control section is divided into a high frequency deflection control section 331 and a low frequency deflection control section 332. The high frequency deflection control section 331 controls an electron beam deflection with an arbitrary frequency and/or arbitrary amplitude in a drawing pattern. The low frequency deflection control section 332 is the same as the deflection control section 33 in Fig. 1. The high frequency deflection control section 331 controls a high frequency deflection electrode 271 which adds high frequency deflection to an electron beam, based on a high speed wobble signal with an arbitrary frequency and/or arbitrary amplitude generated in the formatter 50. While, the low frequency deflection control section 332 controls a low frequency deflection electrode 272 which adds low frequency deflection to an electron beam, based on the saw-toothed deflection signal from the formatter 50. The high speed wobble signal usually has higher frequency than the saw-toothed deflection signal.

An electron beam passed through the high frequency deflection electrode 272 and the low frequency deflection electrode is exposed on the substrate 15. By adding two different frequency deflections to an electron beam through two different electrodes, it is possible to draw various types of patterns more effectively.

In the electron beam recording apparatus (EBR) and control apparatus (formatter) thereof according to the present invention as described in detail above, the number of overwrite cycles, the dose amount, the track pitch, the number of tracks, and other drawing conditions can easily be changed and set by changing the set values relating to the various control signals described above. Consequently, it is possible to provide an electron beam recording apparatus capable of drawing concentric circular tracks with high precision, and that has a high degree of freedom and excellent control properties, and to provide a control apparatus and control method for the same.

Those skilled in the art will appreciate that this invention is not only applied to an electron beam drawing system, method and apparatus, but may also be applied to an ion beam drawing system, method and apparatus.

Claims

1. A control apparatus for an electron beam recording apparatus for translationally moving a substrate in a radial direction of said substrate while rotating the substrate, and radiating an electron beam while deflecting the beam for drawing a concentric circle pattern on said substrate; characterized in comprising: a synchronization signal generator for generating a rotation synchronization signal and a translation synchronization signal to produce an operation clock for rotationally driving and translationally driving said substrate; a deflection signal generator for generating a deflection signal for deflecting said electron beam in synchronism with said translation synchronization signal to overwrite said concentric data pattern so that a beam spot of said electron beam is at the same speed and in the same direction as translation of said substrate through a period in which said substrate is rotated a prescribed number of overwriting cycles in synchronism with said rotation synchronization signal; and a data output section for outputting said concentric circle pattern data in accordance with said number of overwriting cycles in synchronism with said rotation synchronization signal.

2. The control apparatus according to claim 1, characterized in further comprising a setting section for setting said number of overwriting cycles, wherein said deflection signal generator generates said deflection signal in accordance with said number of overwriting cycles.

3. The control apparatus according to claim 1, characterized in that said deflection signal is a signal for deflecting said electron beam to a deflection position occupied at the start of said overwriting, after said overwriting is completed.

4. The control apparatus according to claim 1, characterized in that the frequency of said translation synchronization signal is constant through a period in which said substrate is rotated said prescribed number of overwriting cycles; and said deflection signal is a signal having a sawtooth waveform.

5. A computer program product comprising a computer useable medium having computer useable program code for performing drawing control of an electron beam recording apparatus for radiating an electron beam on a substrate while rotating and translationally moving said substrate; characterized in comprising: computer useable program code for generating a rotation clock and a translation clock for indicating drive amounts of rotational driving and translational driving of said substrate; computer useable program code for computing a deflection amount of said electron beam on the basis of said translation clock so that a radiation position of said electron beam moves at the same speed and in the same direction as translation of said substrate through a period in which said substrate is rotated a prescribed number of times in accordance with said rotation clock; and computer useable program code for issuing an output command for outputting a pattern data in accordance with said prescribed number of times in accordance with said rotation clock.

6. The computer program product according to claim 5, characterized in further comprising computer useable program code for receiving the specification of said prescribed number of times; wherein said deflection amount is based on said specified number of times in the step of specifying said deflection amount.

7. The computer program product according to claim 5, characterized in that after the period of rotation said prescribed number of times is ended, a deflection amount at the start of said period is specified as the deflection amount of said electron beam in the computer useable program code for computing said deflection amount.

8. The computer program product according to claim 5, characterized in a frequency of said translation clock is constant through a period of rotation said prescribed number of times; and a signal having a sawtooth waveform is specified in the computer useable program code for computing said deflection amount.

9. An electron beam recording apparatus for translationally moving a substrate in a radial direction of said substrate while rotating the substrate, and radiating an electron beam while deflecting the beam for drawing data in a concentric circle pattern on said substrate; characterized in comprising: a control section having a synchronization signal generator for generating a rotation synchronization signal and a translation synchronization signal to produce an operation clock for rotationally driving and translationally driving said substrate, a deflection signal generator for generating a deflection signal for deflecting said electron beam in synchronism with said translation synchronization signal to overwrite said data so that a beam spot of said electron beam is at the same speed and in the same direction as translation of said substrate through a period in which said substrate is rotated a prescribed number of overwriting cycles in synchronism with said rotation synchronization signal, and a data output section for outputting said data in accordance with said number of overwriting cycles in synchronism with said rotation synchronization signal; a rotation/translation drive section for rotationally driving and translationally driving said substrate in synchronism with said rotation synchronization signal and translation synchronization signal; an electron beam deflector for deflecting said electron beam in accordance with said deflection signal; and an electron beam modulator for performing drawing with the electron beam in accordance with data outputted from said data output section.

10. The electron beam recording apparatus according to claim 9, characterized in further comprising a setting section for setting said number of overwriting cycles, wherein said deflection signal generator generates said deflection signal in accordance with the set number of overwriting cycles.

11. The electron beam recording apparatus according to claim 9, characterized in that said deflection signal is a signal for deflecting said electron beam to a deflection position occupied at the start of said overwriting, after said overwriting is completed.

12. The electron beam recording apparatus according to claim 9, characterized in that the frequency of said translation synchronization signal is constant through a period in which said substrate is rotated the prescribed number of overwriting cycles; and said deflection signal is a signal having a sawtooth waveform.