Electronic optical focusing, deflexion and signals collection method for the turning gear immerged object lens

Abstract

A four-turn deceleration immersion method that provides a low-voltage electron beam with large beam current, considerable spatial resolution, considerable scanning range, and high signal collection efficiency. The objective includes a magnetic lens for generating a magnetic field near the sample to focus the particles of the particle beam onto the sample, and electrodes for providing a deceleration field near the sample to the potential of the particle beam when the beam collides with the sample. To reduce the energy of the particle beam; a deflection system including a plurality of deflection units arranged along the beam axis for deflecting the particle beam to make scanning on a sample with a large area possible, at least one of the deflection units is placed on the In the deceleration field of the beam, the remaining deflection units are placed in the central cavity of the magnetic lens; and an annular detection unit with a fairly small aperture is placed below the aperture defining the main beam to capture secondary electrons (SE) and backscatter Lining Electronics (BSE).

Description

[0001] This application is a divisional application with the filing date of "March 21, 2002", the application number of "02828993.5", and the title of "Electron Optical Focusing, Deflection and Signal Collection System and Method of Swivel Deceleration Submerged Objective Lens". technical field [0002] The present invention generally relates to a scanning electron microscope, and in particular relates to a focusing and deflection system and method of a rotary deceleration submerged objective lens electron optics. range, and high signal capture efficiency. Background technique [0003] Scanning electron microscopes are used in many applications where the very small structures of objects need to be examined in great detail. Some of these applications include applications such as defect viewing and inspection of samples of very large scale integrated (VLSI) circuits, or chips, or other objects, the determination of detailed critical dimensions in these samples, and the design ...

AI Technical Summary

Problems solved by technology

As a result, detection can only be performed simultaneously on relatively small sample portions without repositioning the sample

Second, the time required to inspect, view and measure a sample is substantially long because of the inherently small deflection range

This not only results in increased IC turnaround time, but also increases the cost of process, test, inspection, troubleshooting and production

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