KR-102961052-B1 - System and method for scanning a sample using multi-beam inspection apparatus

Abstract

The present invention relates to an improved system and method for inspecting a sample using a particle beam inspection device, and more specifically, to a system and method for scanning a sample with multiple charged particle beams. An improved method for scanning an area of a sample using N charged particle beams—wherein N is an integer greater than or equal to 2, and the area of the sample comprises multiple scan sections of N consecutive scan lines—comprising the step of moving the sample in a first direction. The present invention also comprises the step of scanning first scan lines of at least some of the multiple scan sections moving toward the probe spot of the first charged particle beam with a first charged particle beam among the N charged particle beams. The present invention further comprises the step of scanning second scan lines of at least some of the multiple scan sections moving toward the probe spot of the second charged particle beam with a second charged particle beam among the N charged particle beams.

Inventors

• 마센, 마르티누스, 제라르두스, 마리아, 요하네스
• 오텐스, 주스트, 제로엔
• 마, 롱
• 지앙, 요우페이
• 윈, 웨이화
• 리, 웨이-테
• 리우, 슈에동

Assignees

• 에이에스엠엘 네델란즈 비.브이.

Dates

Publication Date

20260508

Application Date

20190607

Priority Date

20180612

Claims (12)

1. In a multi-beam system, A charged particle source for generating a primary beam of charged particles; Beam configuration system; and Sample stage for holding samples Includes, The beam configuration system divides the primary beam of the charged particles into an array of beams, and The array of beams is deflected to scan a set of scan lines covering a surface area of the sample along a first direction, and The sample stage holding the sample is configured to move the sample at a constant speed along a second direction parallel to the first direction, and The above beam configuration system is configured to scan a set of scan lines of a group of scan sections, and each scan section includes a plurality of scan lines, a multi-beam system.
2. delete
3. In paragraph 1, A multi-beam system in which the number of the plurality of scan lines forming each scan section is determined based on the number of beams in the row of the array of beams.
4. In paragraph 1, A multi-beam system in which the scan width of the scan lines of the above scan sections is predetermined but is not limited to the configuration of the array of beams.
5. In paragraph 1, A multi-beam system in which each scan section is scanned as a raster scan pattern.
6. In paragraph 1, The above beam configuration system is a multi-beam system configured to rotate an array of the beams relative to the sample.
7. In paragraph 1, A multi-beam system configured such that the sample stage is configured to rotate the sample with respect to an array of beams.
8. In a non-transient computer-readable medium storing a set of instructions executable by one or more processors of said multi-beam tool to enable said multi-beam tool to perform a method for forming an image of a sample, said method, A step of generating a primary beam of charged particles; A step of dividing the above primary beam into an array of beams; A step of rotating the array of beams with respect to the sample to be scanned by a rotation angle determined based on the number of beams in a row of the array of beams - the array of beams scans a set of scan lines along a first direction, and the set of scan lines covers a surface area of the sample - ; and The method includes the step of moving the sample along a second direction while the array of beams scans a set of scan lines along a first direction, and An array of beams is configured to scan a set of scan lines of a group of scan sections, each scan section comprising a plurality of scan lines, a non-transient computer-readable medium.
9. In paragraph 8, The above second direction is a non-transient computer-readable medium that is substantially perpendicular to the above first direction with respect to the sample.
10. In paragraph 8, The above second direction is a non-transient computer-readable medium that is substantially parallel to the above first direction with respect to the sample.
11. In paragraph 8, The above sample is a non-transient computer-readable medium that is moved at a constant speed by the above multi-beam tool.
12. In paragraph 8, A non-transient computer-readable medium in which the set of scan lines is spaced apart by a distance corresponding to the pixel size of the image generated by the multi-beam tool.

Description

System and method for scanning a sample using a multi-beam inspection apparatus This application claims priority to U.S. Application No. 62/684,138, filed June 12, 2018; U.S. Application No. 62/787,227, filed December 31, 2018; and U.S. Application No. 62/850,461, filed May 20, 2019, the full text of which is incorporated by reference within this application. The embodiments provided herein generally relate to the inspection of a sample using a particle beam inspection device, and more specifically, to a system and method for scanning a sample with a plurality of charged particle beams. When manufacturing semiconductor integrated circuit (IC) chips, pattern defects or uninvited particles (residues) inevitably appear on the wafer or mask during the manufacturing process, reducing the yield. For example, uninvited particles can be a problem in the case of patterns with smaller critical feature dimensions that have been adopted to meet the increasingly advanced performance requirements of IC chips. Pattern inspection tools equipped with a beam of charged particles have been used to detect defects or uninvited particles. Such tools typically utilize a scanning electron microscope (SEM). In an SEM, a beam of primary electrons with relatively high energy is decelerated and lands on a sample with a relatively low landing energy, and is focused to form a probe spot on the sample. Due to this focused probe spot of primary electrons, secondary electrons will be generated from the surface. These secondary electrons may include backscattered electrons, secondary electrons, or Auger electrons resulting from the interaction between the sample and the primary electrons. By scanning the probe spot on the sample surface and collecting the secondary electrons, the pattern inspection tool can acquire an image of the sample surface. The above-mentioned aspects and other aspects of the present disclosure will become more apparent from the description of exemplary embodiments in conjunction with the accompanying drawings. FIG. 1 is a schematic diagram showing an exemplary charged particle beam inspection system consistent with embodiments of the present disclosure. FIG. 2 is a schematic diagram showing an exemplary electron beam tool consistent with embodiments of the present disclosure. Figures 3a and 3b schematically illustrate the inspection of a sample using multiple beams of charged particles. FIGS. 3C and FIGS. 3D schematically illustrate the movement of one of the probe spots in FIGS. 3A and FIGS. 3B for a sample during one of the periods (T1, T2, T3). FIGS. 4a and 4b schematically illustrate the inspection of a sample using multiple beams of charged particles, consistent with embodiments of the present disclosure. FIGS. 5A and 5B schematically illustrate the inspection of a sample using multiple beams of charged particles, consistent with embodiments of the present disclosure. FIG. 6 schematically illustrates the inspection of a sample using multiple beams of charged particles, consistent with embodiments of the present disclosure. FIG. 7 is a schematic diagram showing the steps of an exemplary multi-beam scanning method consistent with embodiments of the present disclosure. FIG. 8a is a schematic diagram showing the distribution of a plurality of primary beamlets on the surface of a sample before and after rotation of the primary beamlets centered on the optical axis of the e-beam inspection system illustrated in FIG. 1, consistent with embodiments of the present disclosure. FIG. 8b is a schematic diagram showing a scanning pattern of a plurality of primary beamlets on the surface of a sample before and after rotation of the primary beamlets around the optical axis of the e-beam inspection system illustrated in FIG. 1, consistent with embodiments of the present disclosure. FIG. 9 is a schematic diagram illustrating a process for selecting a rotation angle for primary beamlets illustrated in FIG. 8a and FIG. 8b, consistent with embodiments of the present disclosure. FIG. 10 is a flowchart of a multi-beam scanning method consistent with embodiments of the present disclosure. FIG. 11 is a schematic diagram showing a multi-beam interlaced scanning pattern consistent with embodiments of the present disclosure. FIG. 12 is a schematic diagram showing the movement trajectories of multiple probe spots on a sample during interlaced scanning, consistent with embodiments of the present disclosure. FIG. 13 is a schematic diagram showing a multi-beam interlaced scanning pattern consistent with embodiments of the present disclosure. FIG. 14 is a flowchart of a multi-beam interlaced scanning method consistent with embodiments of the present disclosure. FIG. 15 is a schematic diagram showing a multi-beam semi-interlaced scanning pattern consistent with embodiments of the present disclosure. FIG. 16 is a flowchart of a multi-beam semi-interlaced scanning method consistent with embodiments of the present disclosure. FIG. 17 is a schematic