A new electron beam lithography system for masks needed in production of 1Gbit DRAM devices was developed and evaluated. The system features a variable shaped beam, 50 kV accelerating voltage, and a step and repeat stage, and incorporates new technologies, including a high resolution high current density electron optical system, a per-shot beam correction unit, a high precision beam detection system utilizing the curve fitting method, and a single-stage 20 bit beam deflection unit. The initial evaluation confirmed a minimum line-width of 100nm, a line-width uniformity of 20 nm within a field, a total positional accuracy, including field stitching and in-field positional accuracy of 20 nm and an exposure speed 3 times faster than that of the existing model, JBX-7000MVII. It was thus verified that the new EB system is capable to produce masks needed for next generation devices including 1 Gbit DRAMs.

Date Published: 1 September 1998
PDF: 12 pages
Proc. SPIE 3412, Photomask and X-Ray Mask Technology V, (1 September 1998); doi: 10.1117/12.328826

Published in SPIE Proceedings Vol. 3412:
Photomask and X-Ray Mask Technology V
Naoaki Aizaki, Editor(s)