Share Email Print

Proceedings Paper

Demonstration of lithography patterns using reflective e-beam direct write
Author(s): Regina Freed; Jeff Sun; Alan Brodie; Paul Petric; Mark McCord; Kurt Ronse; Luc Haspeslagh; Bart Vereecke
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

Traditionally, e-beam direct write lithography has been too slow for most lithography applications. E-beam direct write lithography has been used for mask writing rather than wafer processing since the maximum blur requirements limit column beam current - which drives e-beam throughput. To print small features and a fine pitch with an e-beam tool requires a sacrifice in processing time unless one significantly increases the total number of beams on a single writing tool. Because of the uncertainty with regards to the optical lithography roadmap beyond the 22 nm technology node, the semiconductor equipment industry is in the process of designing and testing e-beam lithography tools with the potential for high volume wafer processing. For this work, we report on the development and current status of a new maskless, direct write e-beam lithography tool which has the potential for high volume lithography at and below the 22 nm technology node. A Reflective Electron Beam Lithography (REBL) tool is being developed for high throughput electron beam direct write maskless lithography. The system is targeting critical patterning steps at the 22 nm node and beyond at a capital cost equivalent to conventional lithography. Reflective Electron Beam Lithography incorporates a number of novel technologies to generate and expose lithographic patterns with a throughput and footprint comparable to current 193 nm immersion lithography systems. A patented, reflective electron optic or Digital Pattern Generator (DPG) enables the unique approach. The Digital Pattern Generator is a CMOS ASIC chip with an array of small, independently controllable lens elements (lenslets), which act as an array of electron mirrors. In this way, the REBL system is capable of generating the pattern to be written using massively parallel exposure by ~1 million beams at extremely high data rates (~ 1Tbps). A rotary stage concept using a rotating platen carrying multiple wafers optimizes the writing strategy of the DPG to achieve the capability of high throughput for sparse pattern wafer levels. The lens elements on the DPG are fabricated at IMEC (Leuven, Belgium) under IMEC's CMORE program. The CMOS fabricated DPG contains ~ 1,000,000 lens elements, allowing for 1,000,000 individually controllable beamlets. A single lens element consists of 5 electrodes, each of which can be set at controlled voltage levels to either absorb or reflect the electron beam. A system using a linear movable stage and the DPG integrated into the electron optics module was used to expose patterns on device representative wafers. Results of these exposure tests are discussed.

Paper Details

Date Published: 4 April 2011
PDF: 12 pages
Proc. SPIE 7970, Alternative Lithographic Technologies III, 79701T (4 April 2011); doi: 10.1117/12.879454
Show Author Affiliations
Regina Freed, KLA-Tencor Corp. (United States)
Jeff Sun, KLA-Tencor Corp. (United States)
Alan Brodie, KLA-Tencor Corp. (United States)
Paul Petric, KLA-Tencor Corp. (United States)
Mark McCord, KLA-Tencor Corp. (United States)
Kurt Ronse, IMEC (Belgium)
Luc Haspeslagh, IMEC (Belgium)
Bart Vereecke, IMEC (Belgium)

Published in SPIE Proceedings Vol. 7970:
Alternative Lithographic Technologies III
Daniel J. C. Herr, Editor(s)

© SPIE. Terms of Use
Back to Top