With the introduction of the NXE:3400B scanner, ASML has brought EUV to High-Volume Manufacturing (HVM). The high EUV power of >200W being realized with this system satisfies the throughput requirements of HVM, but also requires reconsideration of the imaging aspects of spectral purity, both from the details of the EUV emission spectrum and from the DUV emission. This paper will present simulation and experimental results for the spectral purity of high-power EUV systems, and the imaging impact of this, both for the case of with and without a pellicle. Also, possible controls for spectral purity will be discussed, and a novel method will be described to measure imaging impact of varying CE and DUV. It will be shown that CE optimization towards higher source power leads to reduction in relative DUV content, that the small deltas in EUV source spectrum for higher power do not influence imaging. It will also be shown that resulting variations in DUV do not affect imaging performance significantly, provided that a suitable reticle black border is used. In short, spectral purity performance is not a bottleneck for increasing power of EUV systems to well above 250W.
|Number of pages||16|
|Journal||SPIE Conference Proceedings|
|Publication status||Published - 23 Mar 2020|
|Event||SPIE Advanced Litography 2020 - San Jose Convention Center, San Jose, United States|
Duration: 23 Feb 2020 → 27 Feb 2020
- Spectral Purity