| Autor: |
Yamada, Akio, Sakamoto, Kiichi, Yamazaki, Satoru, Kobayashi, Katsuhiko, Sagoh, Satoru, Ohno, Manabu, Hitoshi Watanabe, Hitoshi Watanabe, Hiroshi Yasuda, Hiroshi Yasuda |
| Zdroj: |
Japanese Journal of Applied Physics; December 1994, Vol. 33 Issue: 12 p6959-6959, 1p |
| Abstrakt: |
Beam calibration techniques of an EB block exposure system (NOWEL 3) are developed to determine deflection and correction data to deflect beams through each mask pattern. After the calibration, the current densities in a deflection area differ less than 1.6% from the mean value. The exposure positioning errors are below 0.03 µ m in magnitude. The calibration results are used to expose a repetitive pattern of DRAM storage capacitors. The block mask has doughnut-type structures held by 2 µ m-wide bridges. Rectangular 0.45×0.85 µ m2resist patterns with clear edges are resolved at 0.11 µ m intervals. Repetitive patterns in a logic LSIC are also exposed with the block exposure. We extract mask patterns from the cache memory and shift register regions. The number of exposure spots is decreased to about 1/5 of that used in conventional rectangular shaped beam methods. The stitching errors between the mask patterns are measured from the exposure results, which are less than 0.04 µ m. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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