Microstructured pattern inspection method

• US 8,304,724 B2
• Filed: 08/02/2010
• Issued: 11/06/2012
• Est. Priority Date: 10/07/1999
• Status: Expired due to Term

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Sasajima, Fumihiro, Komuro, Osamu, Mizuno, Fumio
• Primary Examiner(s): Wells, Nikita
• Application Number:
  US12/848,278
• Publication Number:
  US 20100314541A1
• Time in Patent Office: 827 Days
• Field of Search: 250/310, 250/306, 250/307, 250/311, 250/491.1, 250/492.22, 250/492.2, 430/4, 430/3, 382/145
• US Class Current: 250/310
• CPC Class Codes: G01N 23/225 using electron or ion
• CPC Class Codes: G03F 7/70608 Monitoring the unpatterned workpiece, e.g. measuring thickness, reflectivity or effects of immersion liquid on resist
• CPC Class Codes: G06T 7/0004 Industrial image inspection
• CPC Class Codes: H01J 2237/221 Image processing
• CPC Class Codes: H01J 2237/24592 Inspection and quality control of devices
• CPC Class Codes: H01J 2237/2487 using digital signal processors
• 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

The edges of the reticle are detected with respect to the microstructured patterns exposed by the stepper, and the shapes of the microstructured patterns at the surface and at the bottom of the photoresist are detected. The microstructured patterns are evaluated by calculating, and displaying on the screen, the dislocation vector that represents the relationship in position between the detected patterns on the surface and at the bottom of the photoresist. Furthermore, dislocation vectors between the microstructured patterns at multiple positions in a single-chip or single-shot area or on one wafer are likewise calculated, then the sizes and distribution status of the dislocation vectors at each such position are categorized as characteristic quantities, and the corresponding tendencies are analyzed. Thus, stepper or wafer abnormality is detected.

Claims

1. A measurement apparatus to measure a dimension relating to a pattern formed on a specimen based on a detected signal from a scanning electron microscope, wherein the measurement apparatus is constituted to measure a misalignment between a first center of an inner pattern and a second center of an outer pattern, the inner pattern and the outer pattern being positioned at the same layer of the specimen.

2. The measurement apparatus according to claim 1, wherein the inner pattern and the outer pattern belong to the same hole pattern or line pattern.

3. The measurement apparatus according to claim 1, wherein the measurement apparatus is constituted to output the measured misalignment as a measurement result for each chip of the specimen or each shot of an optical exposure apparatus.

4. The measurement apparatus according to claim 1, wherein the measurement apparatus is constituted to calculate a statistical value or a representative value for each chip of the specimen or each shot of an optical exposure apparatus based on the measured misalignment and to output the statistical value or the representative value as a measurement result.

5. The measurement apparatus according to claim 1, wherein the measurement apparatus is constituted to calculate a dislocation vector between the inner pattern and the outer pattern.

6. A measurement apparatus to measure a dimension relating to a pattern formed on a specimen based on a detected signal from a scanning electron microscope, wherein the measurement apparatus is constituted to measure a plurality of misalignments between a plurality of first centers of inner patterns and a plurality of second centers of outer patterns, and to calculate or select a statistical value or a representative value based on the plurality of misalignments, the inner pattern and the outer pattern being positioned at the same layer of the specimen.

7. The measurement apparatus according to claim 6, wherein the inner pattern and the outer pattern belong to the same hole pattern or line pattern.

8. The measurement apparatus according to claim 6, wherein the measurement apparatus is constituted to calculate dislocation vectors between the inner patterns and the outer patterns.