Convergent charged particle beam apparatus and inspection method using same

• US 20040211919A1
• Filed: 05/24/2004
• Published: 10/28/2004
• Est. Priority Date: 02/27/1998
• Status: Active Grant

• Current Assignee: Hiroyuki Shinada, Maki Tanaka, Masahiro Watanabe, Takashi Hiroi, Taku Ninomiya
• Original Assignee: Hiroyuki Shinada, Maki Tanaka, Masahiro Watanabe, Takashi Hiroi, Taku Ninomiya
• Inventors: Ninomiya, Taku, Watanabe, Masahiro, Hiroi, Takashi, Tanaka, Maki, Shinada, Hiroyuki
• Granted Patent: US 6,885,012 B2
• Time in Patent Office: Days
• US Class Current: 250/491.1
• CPC Class Codes: G01N 2001/2893 Preparing calibration standards
• CPC Class Codes: H01J 2237/2817 Pattern inspection
• CPC Class Codes: H01J 2237/304 Controlling tubes
• CPC Class Codes: H01J 37/21 Means for adjusting the focus adjusting the focus while observing the image by photographic or optical means H01J37/22; means for observing the object or the point of impact on the object in tubes for the localised treatment of materials H01J37/3005

Abstract

A convergent charged particle beam apparatus includes an electron beam system which emits a converged electron beam, a vacuum chamber which is connected to the electron beam system, and a stage which mounts a specimen and moves at least in one direction inside of the vacuum chamber. An electron beam image observation unit observes an electron beam image of a surface of the specimen. A height detector optically detects a height of the specimen mounted on the stage by illuminating the surface of said specimen with light and by detecting reflected light of the illumination reflected from the surface of the specimen, and a controller controls a focus position of the electron beam in accordance with an output from the height detector while the stage is moving at least in one direction.

Claims

1. A convergent charged particle beam apparatus comprising:

an electron beam system which emits a converged electron beam;

a vacuum chamber which is connected to the electron beam system;

a stage which mounts a specimen and moves at least in one direction inside of the vacuum chamber;

an electron beam image observation unit which observes an electron beam image of a surface of the specimen mounted on the stage by irradiation of the electron beam emitted from the electron beam system and scanned over the surface of the specimen;

a height detector which optically detects a height of the specimen mounted on the stage by illuminating the surface of said specimen with light and by detecting reflected light of the illumination reflected from the surface of the specimen; and

a controller which controls a focus position of the electron beam in accordance with an output from the height detector while the stage is moving at least in one direction.