Laser-induced extreme UV radiation sources for manufacturing next-generation integrated circuits

Influence of Pre-Ionized Plasma on the Dynamics of a Tin Laser-Triggered Discharge-Plasma

“…An EUV energy monitor E-Mon (Bruker Advanced Supercon GmbH, 00M-EM-001), consisting of a Zr filter, two Mo/Si multilayer mirrors, and an X-ray photo-diode was used to measure pulsed EUV-energies and calibrated the GIS spectra detection system at central wavelength of 13.5 nm with a bandwidth of 2%. XeF, and KrF laser, and the dependence of the EUV source efficiency on the laser power density is obtained as well [16]. The latter studies the EUV spectra generated by picosecond and nanosecond laser triggering under different laser energy.…”

“…It reports that ps-triggering is better in order to get a higher EUV conversion efficiency and narrower spectral profiles [7]. Moreover, the effect of current rise time, electrical energy, and inter-electrode distance are also reported [16,17]. The plasma characteristics during the Z-pinch and recovery stage have been studied extensively by using optical techniques or spectroscopy.…”

“…With a special three electrodes system, Lu et al investigated the post-discharge stage of the LTD EUV source [15], and it shows that that electrical recovery lasts for a few tens to several hundreds of microseconds, and the repetition of the source can exceed 70 kHz, which is useful to achieve high power of the EUV source. Parameters and types of lasers are also investigated by V. M. Borisov et al and G. A. Beyene et al The former reports that the maximum conversion efficiency is almost the same for CO 2 , Nd:YAG, XeF, and KrF laser, and the dependence of the EUV source efficiency on the laser power density is obtained as well [16]. The latter studies the EUV spectra generated by picosecond and nanosecond laser triggering under different laser energy.…”