Scanning electron microscope

• US 7,307,254 B2
• Filed: 04/12/2005
• Issued: 12/11/2007
• Est. Priority Date: 04/19/2004
• Status: Active Grant

• Current Assignee: Hitachi High-Tech Company Limited (Hitachi, Ltd.)
• Original Assignee: Hitachi High-Technologies Corporation (Hitachi, Ltd.)
• Inventors: Yamaguchi, Kohei, Aoki, Kazuo, Isogai, Seiji, Sakamoto, Masashi
• Primary Examiner(s): Toatley, Jr., Gregory J.
• Assistant Examiner(s): UNDERWOOD, JARREAS C
• Application Number:
  US11/103,654
• Publication Number:
  US 20050236569A1
• Time in Patent Office: 973 Days
• Field of Search: 250310-311, 3562371-2372, 438/14
• US Class Current: 250/311
• CPC Class Codes: H01J 2237/2817 Pattern inspection
• CPC Class Codes: H01J 37/265 Controlling the tube; circuit arrangements adapted to a particular application not otherwise provided, e.g. bright-field-dark-field illumination
• CPC Class Codes: H01J 37/28 with scanning beams H01J37/268, H01J37/292, H01J37/2955 take precedence

Abstract

This SEM has a capability of preventing shift of a view field of the foreign matters at a stage where no sufficient correction is carried out when obtaining the SEM coordinate values used for transforming the coordinate values of the foreign matters on the sample sent from another device into the SEM coordinate values. The SEM selects the foreign matters closer to the center of the sample at first and then the foreign matters spirally from the center of the sample to the outer periphery.

Claims

1. A scanning electron microscope comprising:

a moving stage for moving a sample with said sample being held thereon;

means for moving said moving stage to a location indicated by a coordinate value on a corrected coordinate system, said coordinate value being transformed from a coordinate value on a sample coordinate system about one or more foreign matters on said sample obtained by another device through the effect of a coordinates transforming expression generated in accordance with errors between a coordinate value of said foreign matters in said sample coordinate system and a coordinate value indicating actual position of said foreign matters, for observing said foreign matters; and

means for selecting said foreign matters on said sample substantially spirally in the farther direction from the center of said sample with said foreign matter located closer to the center of said sample as a start point.

2. A scanning electron microscope as claimed in claim 1, wherein said coordinates transforming expression is set in a manner to reduce to a minimum an error between the coordinate values on said sample coordinate system about plural foreign matters on said sample obtained by said another device and the coordinate values on said sample coordinate system of said scanning electron microscope in which system said foreign matters are actually observed.

3. A scanning electron microscope as claimed in claim 1, wherein said means for selecting foreign matters has a function of manually setting a condition of enabling said selecting means and/or parameters for prescribing said enabling condition.

4. A scanning electron microscope as claimed in claim 1, wherein said means for selecting foreign matters has a function of automatically setting said condition of enabling said selecting means and/or parameters for prescribing said enabling condition based on any one or more of a history of said enabling condition, information about said foreign matters, information about said sample, and information about said another device.

5. A scanning electron microscope as claimed in claim 1, wherein said means for selecting foreign matters has a vector created on a specific predetermined condition, parameters for prescribing said vector, and parameters in the range of selecting said foreign matters and has a function of selecting said foreign matters on said sample in said selecting range through said vector mediated by varying said two kinds of parameters.

6. A scanning electron microscope as claimed in claim 1, wherein said means for selecting foreign matters has a function of dividing said sample into a plurality of areas defined by closed boundary lines that surround the center of said sample and are not crossed with each other, and selecting said plurality of areas from the central area to the outer area in sequence and at once said foreign matters contained in each of said areas.

7. A scanning electron microscope as claimed in claim 1, wherein said means for selecting foreign matters comprises a process of automatically terminating said selection if a specific condition is met.

8. A scanning electron microscope comprising:

a moving stage for moving a sample with said sample being held thereon;

means for moving said moving stage to a location indicated by a coordinate value on a corrected coordinate system, said coordinate value being transformed from a coordinate value on a sample coordinate system about one or more foreign matters on said sample obtained by another device through the effect of a coordinates transforming expression, for observing said foreign matters; and

means for selecting said foreign matters on said sample substantially spirally in the farther direction from the center of said sample with said foreign matter located closer to the center of said sample as a start point;

wherein said means for selecting foreign matters has a function of automatically setting said condition of enabling said means for selecting and/or parameters for prescribing said enabling condition based on any one or more of a history of said enabling condition, information about said foreign matters, information about said sample, and information about said another device.