System and method for calibrating charge-regulating module

Patent metadata

Field	Value
Publication number	US-9536697-B2
Application number	US-201514716385-A
Country	US
Kind code	B2
Filing date	May 19, 2015
Priority date	May 19, 2015
Publication date	Jan 3, 2017
Grant date	Jan 3, 2017

Abstract

This invention provides a system and a method for calibrating charge-regulation module in vacuum environment. Means for mounting the charge-regulation module provides motions to the charge-regulation module such that a beam spot, illuminated by the charge-regulation module, on a sample surface can be moved to a pre-determined position which is irradiated by a charged particle beam.

First claim

What is claimed is:

1. A system for calibrating a charge-regulating module, comprising:
means for mounting a Laser and providing motions to move the Laser, wherein the Laser illuminates a beam on a surface of a sample with a beam spot thereon, and regulates charges on the sample surface;
a detector for receiving a reflected beam from the beam spot on the sample surface;
a controller, coupled to the detector, for receiving signals from the detector, calculating a position of the beam spot, and controlling the beam spot to a pre-determined location; and
a transmission, coupled to the controller, and driving the mounting means such that the beam spot is moved to the pre-determined location.

2. The system of claim 1 , wherein the mounting means is fastened to an objective lens of a charged particle beam tool, and the pre-determined location is irradiated by a charged particle beam of the charged particle beam tool.

3. The system of claim 2 , wherein the charged particle beam tool is an ebeam inspection tool.

4. The system of claim 3 , wherein the sample is a wafer or a mask.

5. The system of claim 4 , wherein the mounting means includes a first motor for driving the Laser with a rotational motion, and a second motor for driving the Laser with a vertical motion.

6. The system of claim 5 , wherein the transmission is a hollow rod within wires for providing powers and instructions to the first and second motors.

7. The system of claim 4 , wherein the mounting means is a C-shape mount and the Laser is fastened thereto.

8. The system of claim 7 , wherein the transmission includes a rotation-to-translation means.

9. The system of claim 8 , wherein the transmission includes a carved body fastened to the rotation-to-translation means and engaged to the C-shape mount.

10. The system of claim 9 , wherein a portion of the C-shape mount is engaged with the carved body.

11. The system of claim 10 , wherein the portion of the C-shape mount is forced to distort in vertical motion and the portion of the C-shape mount is forced to expand with horizontal motion.

12. An ebeam inspection tool, comprising:
an electron tip for providing an electron source;
an anode for extracting the electron source as a primary electron beam;
a condenser lens for condensing the primary electron beam;
a magnetic objective lens for focusing the primary electron beam on a surface of a sample;
a charge-regulation module, fastened to the magnetic objective lens, for regulating charges on the sample surface; and
a system for calibrating the charge-regulation module, includes:
means for mounting the charge-regulation module and providing motions to move the charge-regulation module, wherein the charge-regulation module illuminates a beam on a surface of a sample with a beam spot thereon;
a detector for receiving a reflected beam from the beam spot on the sample surface;
a controller, coupled to the detector, for receiving signals from the detector, calculating a position of the beam spot, and controlling the beam spot to a pre-determined location; and
a transmission, coupled to the controller, and driving the mounting means such that the beam spot is moved to the pre-determined location.

13. The ebeam inspection tool of claim 12 , wherein the sample is a wafer or a mask.

14. The ebeam inspection tool of claim 13 , wherein the mounting means includes a first motor for driving the charge-regulation module with a rotational motion, and a second motor for driving the charge-regulation module with a vertical motion.

15. The ebeam inspection tool of claim 14 , wherein the transmission is a hollow rod within wires for providing powers and instructions to the first and second motors.

16. The ebeam inspection tool of claim 13 , wherein the mounting means is a C-shape mount and the charge-regulation module is fastened thereto.

17. The ebeam inspection tool of claim 16 , wherein the transmission includes a rotation-to-translation means.

18. The ebeam inspection tool of claim 17 , wherein the transmission includes a carved body fastened to the rotation-to-translation means and engaged to the C-shape mount.

19. The ebeam inspection tool of claim 18 , wherein a portion of the C-shape mount is engaged with the carved body.

20. The ebeam inspection tool of claim 19 , wherein the portion of the C-shape mount is forced to distort in vertical motion and the portion of the C-shape mount is forced to expand with horizontal motion.

21. A method for calibrating a charge-regulation module under vacuum environment, comprising:
providing a beam on a surface of a sample by the charge-regulation module to form a beam spot on the surface, wherein the beam spot regulates charges on the sample surface;
detecting a location of the beam spot according to a reflection of the beam from the sample surface;
calculating a pre-determined position of a charged particle beam on the surface; and
driving the charge-regulation module such that the beam spot moves to the pre-determined position.

Assignees

• Hermes Microvision Inc

Inventors

• Wang yi-xiang
• Zhang Jian
• Zhao Yan

Classifications

• H01J37/265

  Controlling the tube; circuit arrangements adapted to a particular application not otherwise provided, e.g. bright-field-dark-field illumination · CPC title

• H01J37/026 Primary

  Means for avoiding or neutralising unwanted electrical charges on tube components · CPC title

• H01J2237/0047

  using electromagnetic radiations, e.g. UV, X-rays, light · CPC title

• H01J37/28

  with scanning beams {(H01J37/268, H01J37/292, H01J37/2955 take precedence)} · CPC title

• H01J2237/024

  Moving components not otherwise provided for · CPC title