Localized, in-vacuum modification of small structures

Patent metadata

Field	Value
Publication number	US-9812286-B2
Application number	US-201514978180-A
Country	US
Kind code	B2
Filing date	Dec 22, 2015
Priority date	Sep 19, 2011
Publication date	Nov 7, 2017
Grant date	Nov 7, 2017

Abstract

A charge transfer mechanism is used to locally deposit or remove material for a small structure. A local electrochemical cell is created without having to immerse the entire work piece in a bath. The charge transfer mechanism can be used together with a charged particle beam or laser system to modify small structures, such as integrated circuits or micro-electromechanical system. The charge transfer process can be performed in air or, in some embodiments, in a vacuum chamber.

First claim

We claim as follows:

1. A charged particle beam system, comprising:
a vacuum chamber,
a charged particle beam column configured to direct a charged particle beam onto a sample placed inside the vacuum chamber,
a micromanipulator extending within the vacuum chamber, the micromanipulator capable of moving an object with submicron precision,
a movable nano pen connected to the micromanipulator and configured to hold an electrolyte solution, and
an electrode provided at the movable nano pen; and
configured to operate in a state in which:
the charged particle beam, electrolyte solution locally applied to an insulating surface of a substrate by the movable nano pen, and the electrode at the movable nano pen form an electrochemical circuit; and
the charged particle beam functions as a virtual electrode, providing a beam current that completes the electrochemical circuit to support an electrochemical reaction causing deposition of a component of the locally applied electrolyte solution onto the insulating surface.

2. The charged particle beam system of claim 1 , wherein the movable nano pen comprises a nanocapillary, a nano syringe, or a nanopipette.

3. The charged particle beam system of claim 2 , wherein the movable nano pen comprises a nanocapillary having a diameter sufficiently small so that the electrolyte solution is forced out of the nanocapillary by capillary action when the nanocapillary is in contact with a surface.

4. The charged particle beam system of claim 1 , wherein the electrode comprises a wire located inside the movable nano pen.

5. The charged particle beam system of claim 1 , wherein the electrode comprises a conductive coating disposed on the movable nano pen.

6. The charged particle beam system of claim 1 , in which the charged particle beam column is a focused ion beam column and the state is an operating state in which:
the charged particle beam is a positively charged focused ion beam that functions as a virtual anode in the electrochemical circuit;
the electrode at the movable nano pen is negatively biased; and
the electrochemical reaction is an anodic electrochemical reaction induced by positive charges supplied by the positively charged focused ion beam.

7. The charged particle beam system of claim 1 , in which the charged particle beam column is an electron optical column of a scanning electron microscope and the state is an operating state in which:
the charged particle beam is an electron beam that functions as a virtual anode in the electrochemical circuit;
the electrode at the movable nano pen is negatively biased; and
the electrochemical reaction is an anodic electrochemical reaction induced by ejection of negative charges by the electron beam.

8. The charged particle beam system of claim 1 , in which the charged particle beam column is an electron optical column of a scanning electron microscope and the state is an operating state in which:
the charged particle beam is an electron beam that functions as a virtual cathode in the electrochemical circuit;
the electrode at the movable nano pen is positively biased; and
the electrochemical reaction is a cathodic electrochemical reaction induced by negative charges supplied by the electron beam.

9. The charged particle beam system of claim 1 , wherein the state is an operating state in which:
the charged particle beam impinges on the locally applied electrolyte solution; and
the locally applied electrolyte solution is in contact with the electrode at the movable nano pen.

10. The charged particle beam system of claim 9 , further comprising a controller, image recognition software, and an image processor, and wherein:
the charged particle beam column is an electron optical column of a scanning electron microscope,
the image processor is configured to analyze images from the scanning electron microscope with the image recognition software to obtain information about the position and/or state of the movable nano pen; and
the controller is configured to control movement of the movable nano pen in accordance with a predetermined pattern using the micromanipulator and to adjust movement of the movable nano pen using the information.

11. The charged particle beam system of claim 10 , wherein the scanning electron microscope is an environmental scanning electron microscope.

12. The charged particle beam system of claim 1 , further comprising an electrolyte solution contained within the movable nano pen.

13. The apparatus of claim 1 in which the vacuum chamber includes a pressure limiting aperture to maintain the pressure in the charged particle beam column lower than the pressure in the vacuum chamber.

14. The apparatus of claim 1 , wherein the movable nano pen comprises a nanocapillary having an inner diameter of less than 5 μm.

15. The apparatus of claim 14 , wherein the inner diameter is less than 1 μm.

16. The apparatus of claim 15 , wherein the inner diameter is less than 200 nm.

17. The apparatus of claim 1 , further comprising a gas injection system, and wherein:
the micromanipulator forms part of the gas injection system;
the nano pen comprises a nanocapillary;
the gas injection system is modified to include the nanocapillary, the nanocapillary being mounted on or in the gas injection system; and
the gas injection system is capable adjusting the position of the nanocapillary inside the vacuum chamber.

Assignees

• Fei Co

Inventors

• Narum David H
• Toth Milos
• Randolph Steven
• Botman Aurelien Philippe Jean Maclou

Classifications

• C25D5/02

  Electroplating of selected surface areas · CPC title

• H01J37/222

  Image processing arrangements associated with the tube · CPC title

• H01J37/18

  Vacuum locks {; Means for obtaining or maintaining the desired pressure within the vessel} · CPC title

• C25D5/003

  Electroplating using gases, e.g. pressure influence · CPC title

• C25D5/04 Primary

  Electroplating with moving electrodes · CPC title