Charge control device for systems with multiple electron beams

Abstract

Systems and methods for focusing and aligning multiple electron beams are disclosed. The camera produces image data of light from the electron beam projected at the fiber optic array with multiple targets. An image processing module determines adjustments to voltage applied to the relay lens, field lens, or multipole array based on the image data. The adjustment minimizes at least one of displacement, defocus, or aberration of one of the electron beams. Using a control module, the voltage is applied to the relay lens, the field lens, or the multipole array.

Description

[0001] Cross-references to related applications [0002] This application claims priority to provisional patent application filed on May 29, 2018 and assigned to US Application No. 62 / 677,551, the disclosure of which is hereby incorporated by reference. technical field [0003] The present invention relates to the control of electron beams. Background technique [0004] The evolution of the semiconductor manufacturing industry places increasing demands on yield management and, in particular, metrology and inspection systems. Critical dimensions continue to shrink, but industry needs to reduce the time it takes to achieve high-yield, high-value products. Minimizing the total time from detection of yield problems to resolution determines the return on investment for semiconductor manufacturers. [0005] Fabricating semiconductor devices, such as logic and memory devices, typically involves processing a semiconductor wafer using a large number of fabrication processes to for...

AI Technical Summary

Problems solved by technology

[0008] Splitting a single electron beam into numerous beams or creating beam arrays for multi-beam SEM systems is complex

Aligning multiple electron beams is especially challenging

Images