Charged beam drawing apparatus

Abstract

A charged beam drawing apparatus deflects, by an electrostatic deflector, a charged beam generated from a charged beam source, and applies the charged beam to a desired position on a sample to draw a pattern. The electrostatic deflector includes a plurality of deflecting electrodes arranged symmetrically with respect to a point around an optical axis of the charged beam, a ground external cylinder which is disposed coaxially with the optical axis and which is provided to enclose the deflecting electrodes, a resistive film provided on an inner surface of the ground external cylinder, and a conductive film provided on a surface of the resistive film. A capacitance is formed between the deflecting electrodes and the conductive film, and a resistance is formed between the ground conductor and the conductive film.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIG. 1 is a schematic configuration diagram showing an electron beam drawing apparatus according to a first embodiment;

FIG. 2 is a sectional view showing a shaping deflector used in the first embodiment cut in a direction perpendicular to an optical axis direction;

FIG. 3 is a sectional view showing the shaping deflector used in the first embodiment cut along the optical axis direction;

FIG. 4 is an equivalent circuit diagram showing how the deflector in the first embodiment is connected to a deflection amplifier;

FIG. 5 is a sectional view showing a modification of the first embodiment;

FIGS. 6A and 6B are schematic diagrams explaining a function of the first embodiment and showing a change of impedance in a lower frequency region and a high frequency region;

FIG. 7 is a sectional view showing a shaping deflector used in a second embodiment cut in a direction perpendicular to an optical axis direction; and

FIG. 8 is a sectional view showing a shaping deflector used in a third embodiment cut in a direction perpendicular to an optical axis direction.

Claims

1. A charged beam drawing apparatus comprising: a charged beam source which generates a charged beam;an electrostatic deflector provided on a downstream side of the charged beam source to apply a charged beam to a desired position on a sample, the electrostatic deflector including a plurality of deflecting electrodes insulated from a ground plane with respect to a direct current to deflect the charged beam by an electric field and, a capacitance and an electric resistance arranged in series between the deflecting electrodes and the ground plane.

2. The apparatus according to claim 1, further comprising dielectrics arranged between the deflecting electrodes and the ground plane to form the capacitance therebetween and support mechanically the deflecting electrodes.

3. The apparatus according to claim 1, further comprising a deflection amplifier to apply a potential to each of the electrodes to generate the electric field between the electrodes, a time constant decided by a product of the capacitance and the electric resistance being shorter than a setting time of the deflection amplifier.

4. The apparatus according to claim 1, further comprising a deflection amplifier to apply a potential to each of the electrodes to generate the electric field between the electrodes and a coaxial cable connecting the electrostatic deflector to an output end of the deflection amplifier, the electric resistance being substantially equal to a characteristic impedance of the coaxial cable.

5. The apparatus according to claim 1, wherein the capacitance between the deflecting electrodes and the ground plane is greater than a capacitance between the adjacent ones of the deflecting electrodes.

6. The apparatus according to claim 1, wherein the electrostatic deflector comprises a shaping deflector which varies dimensions and a shape of the charged beam.

7. A charged beam drawing apparatus comprising: a charged beam source which generates a charged beam; andan electrostatic deflector provided on a downstream side of the charged beam source to deflect the charged beam by an electric field, the electrostatic deflector comprising:a plurality of deflecting electrodes arranged symmetrically with respect to a point around an optical axis of the charged beam,a ground external cylinder which is disposed coaxially with the optical axis and which is provided to enclose the deflecting electrodes,a resistive film provided on an inner surface of the ground external cylinder, anda conductive film provided on a surface of the resistive film, whereina capacitance is formed between the deflecting electrodes and the conductive film, and an electric resistance is made of the resistive film between the ground external cylinder and the conductive film.

8. The apparatus according to claim 7, further comprising dielectrics arranged between the deflecting electrodes and the conductive film to form the capacitance therebetween and to mechanically support the deflecting electrodes.

9. The apparatus according to claim 7, further comprising a deflection amplifier to apply a potential to each of the electrodes to generate the electric field between the electrodes, a time constant decided by a product of the capacitance and the electric resistance being shorter than a setting time of the deflection amplifier.

10. The drawing apparatus according to claim 7, further comprising a deflection amplifier to apply a potential to each of the electrodes to generate the electric field between the electrodes and a coaxial cable connecting the electrostatic deflector to an output end of the deflection amplifier, the electric resistance being substantially equal to a characteristic impedance of the coaxial cable.

11. The apparatus according to claim 7, wherein the capacitance between the deflecting electrodes and the conductive film is greater than a capacitance between the adjacent ones of the deflecting electrodes.

12. The apparatus according to claim 7, wherein the electrostatic deflector comprises a shaping deflector which varies dimensions and a shape of the charged beam.

13. An electron beam drawing apparatus comprising: an electron gun which generates an electron beam;an electron lens provided on a downstream side of the electron gun to focus the electron beam; andan electrostatic deflector provided on the downstream side of the electron gun to deflect the electron beam by an electric field, the electrostatic deflector comprising:a plurality of deflecting electrodes arranged symmetrically with respect to a point around an optical axis of the electron beam,a ground external cylinder disposed coaxially with the optical axis and provided to enclose the deflecting electrodes,resistive films provided on an inner surface of the ground external cylinder to face the deflecting electrodes,conductive films provided on surfaces of the resistive films, anddielectric films inserted between the conductive films and the deflecting electrodes to mechanically support the deflecting electrodes, whereina capacitance is formed by the dielectric films between the deflecting electrodes and the conductive films, and an electric resistance is formed by the resistive films between the ground external cylinder and the conductive films.

14. The apparatus according to claim 13, further comprising a deflection amplifier to apply a potential to each of the electrodes to generate the electric field between the electrodes, a time constant decided by a product of the capacitance and the electric resistance being shorter than a setting time of the deflection amplifier.

15. The apparatus according to claim 13, further comprising a deflection amplifier to apply a potential to each of the electrodes to generate the electric field between the electrodes and a coaxial cable connecting the electrostatic deflector to an output end of the deflection amplifier, the electric resistance being substantially equal to a characteristic impedance of the coaxial cable.

16. The apparatus according to claim 13, wherein the capacitance between the deflecting electrodes and the conductive films is greater than a capacitance between the adjacent ones of the deflecting electrodes.

17. The apparatus according to claim 13, wherein the electrostatic deflector comprises a shaping deflector which varies dimensions and a shape of the electron beam.