Field-emission electron source apparatus

Abstract

An electron beam emitted from a field-emission electron source array passes through a plurality of through holes formed in a trimming electrode and reaches a target. Each of the plurality of through holes in the trimming electrode has an opening on a side of the field-emission electron source array and an electron beam passageway that continues from the opening. The length of the electron beam passageway is larger than the diameter of the opening. Part of the electron beam that has entered the through holes is absorbed and removed by a lateral wall of the electron beam passageway. In this way, it is possible to provide a high-definition field-emission electron source apparatus in which divergence of an electron beam emitted from a field-emission electron source array is suppressed.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view showing a field-emission electron source apparatus according to Embodiment 1 of the present invention.

FIG. 2 is a schematic perspective view showing a trimming electrode used in the field-emission electron source apparatus according to Embodiment 1 of the present invention.

FIG. 3 is a partially enlarged perspective view showing through holes formed in a trimming portion of the trimming electrode used in the field-emission electron source apparatus according to Embodiment 1 of the present invention.

FIGS. 4A and 4B are partially enlarged sectional views taken along a thickness direction showing the trimming portion of the trimming electrode used in the field-emission electron source apparatus according to Embodiment 1 of the present invention.

FIG. 5 is an exploded perspective view showing the field-emission electron source apparatus according to Embodiment 1 of the present invention.

FIG. 6 is a sectional view showing an example of a field-emission electron source array in the field-emission electron source apparatus according to Embodiment 1 of the present invention.

FIG. 7 is a partially enlarged sectional view showing the field-emission electron source apparatus according to Embodiment 1 of the present invention.

FIGS. 8A and 8B show simulation results in the field-emission electron source apparatus according to Embodiment 1 of the present invention.

FIGS. 9A and 9B show simulation results in the field-emission electron source apparatus according to Embodiment 1 of the present invention.

FIG. 10 is a sectional view showing another example of the field-emission electron source array in the field-emission electron source apparatus according to Embodiment 1 of the present invention.

FIG. 11 is a sectional view showing another field-emission electron source apparatus according to Embodiment 1 of the present invention.

FIG. 12 is a partially enlarged sectional view showing a field-emission electron source apparatus according to Embodiment 2 of the present invention.

FIG. 13 is a partially enlarged sectional view taken along a thickness direction showing a trimming portion of a trimming electrode used in the field-emission electron source apparatus according to Embodiment 2 of the present invention.

FIGS. 14A and 14B are partially enlarged perspective views showing the trimming portion of the trimming electrode used in the field-emission electron source apparatus according to Embodiment 2 of the present invention.

FIGS. 15A to 15D are sectional views showing processes in a method for manufacturing the trimming electrode used in the field-emission electron source apparatus according to Embodiment 2 of the present invention.

FIGS. 16A to 16C are enlarged sectional views each showing an exemplary shape near an opening on a field-mission electron source array side of a through hole of the trimming electrode used in the field-emission electron source apparatus according to Embodiment 2 of the present invention.

FIGS. 17A and 17B show simulation results in the field-emission electron source apparatus according to Embodiment 2 of the present invention.

FIGS. 18A and 18B show simulation results in the field-emission electron source apparatus according to Embodiment 2 of the present invention.

FIG. 19 is a partially enlarged sectional view showing a field-emission electron source apparatus according to Embodiment 3 of the present invention.

FIG. 20 is a partially enlarged sectional view taken along a thickness direction showing a trimming portion of a trimming electrode used in the field-emission electron source apparatus according to Embodiment 3 of the present invention.

FIG. 21 is a sectional view showing a field-emission electron source apparatus according to Embodiment 4 of the present invention.

FIG. 22 is a partially enlarged sectional view showing a field-emission electron source apparatus according to Embodiment 6 of the present invention.

FIG. 23 is a partially enlarged sectional view showing another field-emission electron source apparatus according to Embodiment 6 of the present invention.

FIG. 24 is a partially enlarged sectional view showing a field-emission electron source apparatus according to Embodiment 7 of the present invention.

FIG. 25 is a sectional view showing a conventional field-emission electron source apparatus using a field-emission electron source array.

FIG. 26 is a sectional view showing another conventional field-emission electron source apparatus-using a field-emission electron source array.

Claims

1. A field-emission electron source apparatus comprising: a field-emission electron source array;a target for performing a predetermined operation using an electron beam emitted from the field-emission electron source array; anda trimming electrode that is disposed between the field-emission electron source array and the target and provided with a plurality of through holes through which the electron beam emitted from the field-emission electron source array passes;wherein each of the plurality of through holes has an opening on a side of the field-emission electron source array and an electron beam passageway that continues from the opening,a length of the electron beam passageway is larger than a diameter of the opening, andpart of the electron beam is absorbed and removed by a lateral wall of the electron beam passageway.

2. The field-emission electron source apparatus according to claim 1, wherein the trimming electrode comprises a base layer that constitutes a major part of the trimming electrode and a thin film layer that is formed on a surface of the base layer and has a lower resistance than the base layer.

3. A field-emission electron source apparatus comprising: a field-emission electron source array;a target for performing a predetermined operation using an electron beam emitted from the field-emission electron source array; anda trimming electrode that is disposed between the field-emission electron source array and the target and provided with a plurality of through holes through which the electron beam emitted from the field-emission electron source array passes;wherein each of the plurality of through holes has an opening on a side of the field-emission electron source array and an electron beam passageway that continues from the opening, andthe trimming electrode comprises at least two electrode layers and at least one intermediate layer disposed between the at least two electrode layers.

4. The field-emission electron source apparatus according to claim 3, wherein the at least one intermediate layer is an insulating layer, and the at least two electrode layers form at least two potential spaces in the electron beam passageway.

5. The field-emission electron source apparatus according to claim 3, wherein one of the at least two electrode layers is a first electrode layer that is disposed on the side of the field-emission electron source array with respect to the at least one intermediate layer and supplied with a first voltage, and the other is a second electrode layer that is disposed on a side of the target with respect to the at least one intermediate layer and supplied with a second voltage, and the at least one intermediate layer is a high resistance layer that has a higher resistance than the first electrode layer and the second electrode layer.

6. The field-emission electron source apparatus according to claim 3, satisfying V1>V2, where V1 indicates a voltage to be applied to a first electrode layer in the at least two electrode layers that is disposed on the side of the field-emission electron source array with respect to the at least one intermediate layer, and V2 indicates a voltage to be applied to a second electrode layer in the at least two electrode layers that is disposed on a side of the target with respect to the at least one intermediate layer.

7. The field-emission electron source apparatus according to claim 3, satisfying T1<<T2, where a first electrode layer is an electrode layer in the at least two electrode layers that is disposed on the side of the field-emission electron source array with respect to the at least one intermediate layer, a second electrode layer is an electrode layer in the at least two electrode layers that is disposed on a side of the target with respect to the at least one intermediate layer, T1 indicates a length of the first electrode layer in a length of the electron beam passageway, and T2 indicates a length of the second electrode layer in the length of the electron beam passageway.

8. The field-emission electron source apparatus according to claim 1, further comprising a substrate on which the field-emission electron source array is formed, wherein the trimming electrode has a spacer portion that is formed as one piece with the trimming electrode and spaces out the field-emission electron source array and the openings of the plurality of through holes from each other, andthe trimming electrode is provided on the substrate via the spacer portion.

9. The field-emission electron source apparatus according to claim 8, wherein the spacer portion and the substrate are joined using an electrically conductive material, and a voltage is supplied to at least part of the trimming electrode from the substrate via the electrically conductive material.

10. The field-emission electron source apparatus according to claim 1, wherein the plurality of through holes in the trimming electrode are formed by drilling a silicon substrate deeply such that a length of the electron beam passageway is larger than a diameter of the opening.

11. The field-emission electron source apparatus according to claim 10, wherein the trimming electrode comprises a silicon layer and an insulating layer formed of SiO2.

12. The field-emission electron source apparatus according to claim 1, wherein at least one of a surface of the trimming electrode on the side of the field-mission electron source array and a surface of the trimming electrode on a side of the target is provided with an electrically conductive thin film.

13. The field-emission electron source apparatus according to claim 3, wherein when V1 indicates a voltage to be applied to a first electrode layer in the at least two electrode layers that is disposed on the side of the field-emission electron source array with respect to the at least one intermediate layer and V2 indicates a voltage to be applied to a second electrode layer in the at least two electrode layers that is disposed on a side of the target with respect to the at least one intermediate layer, an amount of an electron beam that passes through the plurality of through holes in the trimming electrode and travels toward the target is varied by changing one or both of the voltage V1 and the voltage V2 while driving the field-emission electron source apparatus.

14. The field-emission electron source apparatus according to claim 1, further comprising a pre-focusing electrode for pre-focusing the electron beam emitted from the field-emission electron source array, the pre-focusing electrode being provided between the field-emission electron source array and the trimming electrode.

15. The field-emission electron source apparatus according to claim 1, wherein a cross-sectional shape of the electron beam passageway along a direction perpendicular to a direction in which the electron beam passageway extends is a circle, an ellipse, a polygon with all interior angles being larger than 90° or a polygon whose adjacent sides are connected by a circular arc.

16. The field-emission electron source apparatus according to claim 1, wherein the field-emission electron source array comprises a plurality of cells comprising a plurality of electron sources each emitting electrons, the field-emission electron source array and the trimming electrode are arranged such that the plurality of openings and the plurality of cells are in one-to-one correspondence with each other in a vertical direction, andan electron beam emitted from the cell enters the corresponding opening, passes through the electron beam passageway and reaches the target.

17. A method for driving a field-emission electron source apparatus comprising a field-emission electron source array,a target for performing a predetermined operation using an electron beam emitted from the field-emission electron source array, anda trimming electrode that is disposed between the field-emission electron source array and the target and provided with a plurality of through holes through which the electron beam emitted from the field-emission electron source array passes,wherein each of the plurality of through holes has an opening on a side of the field-emission electron source array and an electron beam passageway that continues from the opening,the trimming electrode comprises at least two electrode layers and at least one intermediate layer disposed between the at least two electrode layers, andwhen V1 indicates a voltage to be applied to a first electrode layer in the at least two electrode layers that is disposed on the side of the field-emission electron source array with respect to the at least one intermediate layer and V2 indicates a voltage to be applied to a second electrode layer in the at least two electrode layers that is disposed on a side of the target with respect to the at least one intermediate layer, an amount of an electron beam that passes through the plurality of through holes in the trimming electrode and travels toward the target is varied by changing one or both of the voltage V1 and the voltage V2 while driving the field-emission electron source apparatus.

18. The field-emission electron source apparatus according to claim 3, further comprising a substrate on which the field-emission electron source array is formed, wherein the trimming electrode has a spacer portion that is formed as one piece with the trimming electrode and spaces out the field-emission electron source array andthe openings of the plurality of through holes from each other, and the trimming electrode is provided on the substrate via the spacer portion.

19. The field-emission electron source apparatus according to claim 3, wherein the plurality of through holes in the trimming electrode are formed by drilling a silicon substrate deeply such that a length of the electron beam passageway is larger than a diameter of the opening.

20. The field-emission electron source apparatus according to claim 3, wherein at least one of a surface of the trimming electrode on the side of the field-emission electron source array and a surface of the trimming electrode on a side of the target is provided with an electrically conductive thin film.

21. The field-emission electron source apparatus according to claim 3, further comprising a pre-focusing electrode for pre-focusing the electron beam emitted from the field-emission electron source array, the pre-focusing electrode being provided between the field-emission electron source array and the trimming electrode.

22. The field-emission electron source apparatus according to claim 3, wherein a cross-sectional shape of the electron beam passageway along a direction perpendicular to a direction in which the electron beam passageway extends is a circle, an ellipse, a polygon with all interior angles being larger than 90° or a polygon whose adjacent sides are connected by a circular arc.

23. The field-emission electron source apparatus according to claim 3, wherein the field-emission electron source array comprises a plurality of cells comprising a plurality of electron sources each emitting electrons, the field-emission electron source array and the trimming electrode are arranged such that the plurality of openings and the plurality of cells are in one-to-one correspondence with each other in a vertical direction, andan electron beam emitted from the cell enters the corresponding opening, passes through the electron beam passageway and reaches the target.