Method and device for operating a liquid metal-ion source or liquid metal electron source as well as a liquid metal-ion source or liquid metal electron source

Patent metadata

Field	Value
Publication number	US-11705299-B2
Application number	US-202117339937-A
Country	US
Kind code	B2
Filing date	Jun 4, 2021
Priority date	Jun 5, 2020
Publication date	Jul 18, 2023
Grant date	Jul 18, 2023

Abstract

The invention relates to a liquid metal-ion beam system ( 1 ) or liquid metal electron beam system, including:
a conductive emitter electrode ( 2 ), a conductive extractor electrode ( 3 ) opposite to the emitter electrode ( 2 ), a liquid metal reservoir ( 4 ) which is fluidically connected to the emitter electrode ( 2 ) for transporting liquid metal to the emitter electrode ( 2 ), a control unit ( 5 ) which is configured to apply a periodically varying operating voltage between emitter electrode ( 2 ) and extractor electrode ( 3 ).

First claim

The invention claimed is:

1. A liquid metal-ion beam system or liquid metal electron beam system comprising:
a conductive emitter electrode,
a conductive extractor electrode opposite to the emitter electrode,
a liquid metal reservoir which is fluidically connected to the emitter electrode for transporting liquid metal to the emitter electrode, and
a control unit which is configured to apply a periodically varying operating voltage between the emitter electrode and the extractor electrode.

2. The liquid metal-ion beam system or liquid metal electron beam system according to claim 1 , wherein an operating voltage threshold is predetermined which defines a voltage amount above which liquid metal, which is not ionized or is only slightly ionized at the emitter electrode, is extracted by emitted ions or electrons accelerated in the direction of the extractor electrode, wherein the control unit is configured to vary the periodically varying operating voltage between a below-threshold voltage, which is below the operating voltage threshold in terms of amount, and an above-threshold voltage, which is above the operating voltage threshold in terms of amount.

3. The liquid metal-ion beam system or liquid metal electron beam system according to claim 1 , wherein the operating voltage is generated by a constant high voltage source for providing a constant high voltage and a pulse voltage source for providing a periodically varying pulse voltage, connected in series with the arrangement of the emitter electrode and the extractor electrode, wherein the sum of the voltages of the constant high voltage source and the pulse voltage source yields the periodically varying operating voltage.

4. The liquid metal-ion beam system or liquid metal electron beam system according to claim 3 , wherein the pulse voltage source is connected to a reference potential, in particular a ground potential.

5. The liquid metal-ion beam system or liquid metal electron beam system according to claim 1 , wherein the emitter electrode is configured to be a tip electrode or a capillary electrode.

6. The liquid metal-ion beam system or liquid metal electron beam system according to claim 1 , wherein the control unit is configured to adjust the periodically varying operating voltage by a regulated operation, wherein the operating voltage is reduced in terms of amount below the operating voltage threshold, when the current flow through the arrangement of emitter electrode and extractor electrode exceeds in terms of amount a current intensity above a predetermined current threshold and/or when a current gradient rises in terms of amount above a predetermined gradient threshold, and wherein the operating voltage is raised above the operating voltage threshold, when the current flow through the arrangement of emitter electrode and extractor electrode falls below a current intensity above a predetermined current threshold in terms of amount and/or a current gradient falls below a predetermined gradient threshold in terms of amount.

7. The liquid metal-ion beam system according to claim 1 , wherein the pulse frequency of the operating voltage is more than 100 kHz and less than 100 MHz.

8. The liquid metal electron beam system according to claim 1 , wherein the pulse frequency of the operating voltage is more than 1 MHz and less than 1 GHz.

9. A method for operating a liquid metal-ion beam system or liquid metal electron beam system, comprising:
a conductive emitter electrode,
a conductive extractor electrode opposite to the emitter electrode,
a liquid metal reservoir which is fluidically connected to the emitter electrode for transporting liquid metal to the emitter electrode, wherein a periodically varying operating voltage is applied between the emitter electrode and the extractor electrode.

10. A system comprising a liquid metal-ion beam system and a liquid metal electron beam system, the system comprising:
a conductive emitter electrode,
a conductive extractor electrode opposite to the emitter electrode,
a liquid metal reservoir which is fluidically connected to the emitter electrode for transporting liquid metal to the emitter electrode, and
a control unit which is configured to apply a periodically varying operating voltage between the emitter electrode and the extractor electrode,
wherein the control unit applies a positive operating voltage between the emitter electrode and the extractor electrode to emit ions from the emitter electrode,
wherein the control unit applies a negative operating voltage between the emitter electrode and the extractor electrode to emit electrons from the emitter electrode, and
wherein the operating voltages relate to a same reference potential.

11. The system according to claim 10 , wherein the liquid metal-ion beam system and the liquid metal electron beam system are operated with identical pulse frequencies, in particular phase-shifted, in order to reduce an alternating load of an electrical energy storage device.

Assignees

• Univ Dresden Tech

Inventors

• Tajmar Martin

Classifications

• F03H1/005

  using field emission, e.g. Field Emission Electric Propulsion [FEEP] · CPC title

• H01J37/073 Primary

  Electron guns using field emission, photo emission, or secondary emission electron sources · CPC title

• H01J27/22 Primary

  Metal ion sources · CPC title

• B64G1/413

  Ion or plasma engines · CPC title

• H01J27/26

  using surface ionisation, e.g. field effect ion sources, thermionic ion sources (H01J27/20, H01J27/24 take precedence) · CPC title