KrF light source
Resolution (nm)
Projection optics
Wafers per hour
Key features & benefits
The TWINSCAN NXT:870 step-and-scan system is a high-productivity, dual-stage KrF lithography machine designed for volume production of 300 mm wafers at and below 110 nm resolution and is based on the highly reliable, ultrafast NXT platform widely used in ASML’s dry ArFi and ArF systems.
By combining the imaging power of a variable 0.55–0.80 NA ZEISS Starlith 865 4X reduction lens with AERIAL II and the optional QUASAR XL illuminator technology, the NXT:870 extends today’s volume-proven KrF technology to 110 nm applications.
01.Productivity
In this system, highly line-narrowed 40 & 60 W KrF lasers with variable frequency control are used in combination with the high optical transmission of the optical system, providing a production throughput of 330 300-mm wafers per hour at a low operational cost.
The AERIAL II Illuminator also enables continuous-variable conventional and off-axis illumination with zoom optics, and the system’s high-speed, dual-stage technology helps to maintain these high throughput levels over a wide range of resist sensitivities.
02. Optics
The TWINSCAN NXT:870 step-and-scan system includes a variable 0.80 NA 248 nm 865 projection lens to attain very low aberration levels for tight focal planes and excellent distortion control with annular distortion of ≤ 10 nm.
03. Imaging performance
The TWINSCAN NXT:870 step-and-scan system can achieve a ≤ 7.5 nm matched-machine (to reference wafer) full-wafer-coverage overlay. The system’s PARIS sensor allows customers to more accurately set up the system and monitor its imaging parameters.
