Abstract
In order to markedly improve the resolution of photolithography without improving the resolution of exposure systems, the authors propose a simple and effective phase shifting mask technology. The mask has self-aligned phase shifters which do not require assistant patterns and or complicated design of the phase shifter patterns, which are essential to the conventional phase shifting mask. The mask with a phase shifter size of 0.5 μm reduces the width of photointensity to 60% of that without phase shifters, while keeping high contrasts. The authors have fabricated the phase shifting mask and obtained 0.2-μm line resist patterns with a high-contrast resist profile by a KrF excimer laser stepper with resolution capability of 0.4 μm. The proposed phase shifting mask method is extremely attractive for a future ULSI lithography tool in 256-Mb DRAM (dynamic RAM) and beyond.
Original language | English |
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Pages (from-to) | 57-60 |
Number of pages | 4 |
Journal | Technical Digest - International Electron Devices Meeting |
Publication status | Published - 1989 Dec 1 |
Event | 1989 International Electron Devices Meeting - Technical Digest - Washington, DC, USA Duration: 1989 Dec 3 → 1989 Dec 6 |
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering
- Materials Chemistry