Abstract
Extreme ultraviolet lithography (EUVL) is one of all candidate next-generation lithography technologies targeting 45 nm features, the industrial throughput should be more than 80 wafers-per-hour. As the throughput requirements are increased, the incident EUV power on reticle density rise. About 100% the incident power is absorbed by the absorber layer and 35% is absorbed by Mo/Si multi-layers to result in a significant thermal distortion in the reticle. Such effects can contribute to reticle-wafer overlay error, so it is necessary to quantify the reticle distortion. In this work, detailed three-dimensional thermal and structure models have been developed using finite element methods. The results show that the maximum in-plane distortion in x-y plane and z indirection are respectively about 1.11 nm and 0.26 nm when the sensitivity of the resist and the EUV power density are respectively 7 mJ/cm2 and 259.24 W/cm2, and they are respectively about 0.71 nm and 0.19 nm when the sensitivity and the power density are 5 mJ/cm2 and 184.38 W/cm2 respectively.
Original language | English |
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Pages (from-to) | 21-24 |
Number of pages | 4 |
Journal | Weixi Jiagong Jishu/Microfabrication Technology |
Issue number | 4 |
Publication status | Published - Aug 2006 |
Externally published | Yes |
Keywords
- EUVL
- Exposure
- Finite element method
- Resist
- Reticle
- Thermal distortion