The high-performance beam deflection system of EL3

Publisher Website
Google Scholar
Abstract
A new concept of beam deflection was developed and implemented to achieve the high throughput and resolution performance of EL3. It combines the advantages of raster and vector writing techniques by dividing the field into overlapping subfields which are addressed by stepped raster magnetic deflection. Within each subfield electric deflection vectorially writes the pattern elements at high speed. The advantages of dual channel deflection and yokes within the projection lens are fully exploited. The repetitive raster deflection pattern permits the use of an automatic calibration system which corrects beam positioning errors of both deflection channels for fields up to 10 mm. Automatic calibration is utilized to assure good pattern overlay between optical and e‐beam lithography tools to eliminate dedicated tool restrictions. It establishes subfield matching so that patterns are stitched together properly. In addition, overall field size and linearity are controlled to the accuracy and stability required. This paper discusses key aspects of the entire deflection system design, its components, and highlights compatibility questions and trade‐offs between them. Specific problems such as thermal stability, speed/accuracy trade‐offs, noise sources, and their solutions are presented. Calibration data are presented to illustrate the accuracy and stability achieved.

This publication has 0 references indexed in Scilit: