Share Email Print
cover

Proceedings Paper

Development of a LEEPL mask: flatness and IP measurements
Author(s): Yuuki Aritsuka; Minoru Kitada; Masaru Kurosawa; Tadahiko Takikawa; Hiroshi Fujita; Hisatake Sano; Morihisa Hoga; Naoya Hayashi
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

Masks for low energy electron proximity projection lithography (LEEPL) are fabricated starting with 200 mm silicon-on-insulator (SOI) wafers. The effect of the thickness of the buried oxide (BOX) layer of an SOI wafer on its flatness has been investigated. The wafer flatness is found to decrease as the BOX layer becomes thin. When the SOI layer (Si membrane) is not doped by B or P, the membrane has a compressive stress even for a 0.2 μm thick BOX layer. A monitor mask with image placement (IP) marks on a single-large (24 mm square) membrane area has been fabricated, starting with an SOI wafer with an 1.1 μm thick stress-controlled SOI layer and a 0.2 μm thick BOX layer. The internal stress of the membrane was 19 +/- 6 MPa (3σ) (tensile), and the membrane flatness was 0.8 μm. An ES chuck for an LSM-IPRO, which holds a mask in the method compatible with that in LEEPL exposure tools, has been installed. Chucking reduced the mask flatness from 22 μm to 10 μm while the membrane flatness was kept less than 1.0 µm. The dynamic repeatability of IP measurement was 7.6 nm (x) and 4.8 nm (y) in 3σ. The IP error of the monitor mask that had only IP marks was 17 nm (x) and 17 nm (y) in 3σ, satisfying the specification of 30 nm or less.

Paper Details

Date Published: 20 August 2004
PDF: 9 pages
Proc. SPIE 5446, Photomask and Next-Generation Lithography Mask Technology XI, (20 August 2004); doi: 10.1117/12.557777
Show Author Affiliations
Yuuki Aritsuka, Dai Nippon Printing Co., Ltd. (Japan)
Minoru Kitada, Dai Nippon Printing Co., Ltd. (Japan)
Masaru Kurosawa, Dai Nippon Printing Co., Ltd. (Japan)
Tadahiko Takikawa, Dai Nippon Printing Co., Ltd. (Japan)
Hiroshi Fujita, Dai Nippon Printing Co., Ltd. (Japan)
Hisatake Sano, Dai Nippon Printing Co., Ltd. (Japan)
Morihisa Hoga, Dai Nippon Printing Co., Ltd. (Japan)
Naoya Hayashi, Dai Nippon Printing Co., Ltd. (Japan)


Published in SPIE Proceedings Vol. 5446:
Photomask and Next-Generation Lithography Mask Technology XI
Hiroyoshi Tanabe, Editor(s)

© SPIE. Terms of Use
Back to Top