The imaging of living specimens in water by x-ray microscopy can be greatly enhanced with the use of an intense flash x-ray source and sophisticated technologies for reading x-ray images. A subnanosecond [corrected] x-ray pulse from a laser-produced plasma was used to record the x-ray image of living sea urchin sperm in an x-ray resist. The resist relief was visualized at high resolution by atomic-force microscopy. Internal structure of the sperm head was evident, and the carbon density in a flagellum was estimated from the relief height.

No abstract

An analytical formula for maximizing radiation efficiency from a laser-produced plasma is derived. The maximum efficiency is achieved when the plasma expansion distance during laser heating is equal to the laser absorption length. The dependence of the radiation efficiency on the plasma density is confirmed by experiments using a particle-cluster target. By creating a relatively uniform density plasma with a 300 microm diameter by dispersing SnO(2) particles coated on a Si wafer, the conversion efficiency at 14 nm, as high as 4 times as that for a Sn plate target, is achieved.

Extreme-ultraviolet laser amplification has been observed for the Cvi Balmer-a transition at 18.2 nm, with use of a novel optical system to irradiate up to 1 cm length of carbon-fiber target. The measurements were time resolved and indicated peak single-transit amplification of about 30 times.

Abstract. Today intermediate-focus equivalent extreme ultraviolet (EUV) power of several watts is now available, and EUV lithography scanners are being considered as potential scanners for high-volume manufacturing (HVM) tools. However, for high-volume manufacturing with throughput of over 100 wafers per hour, EUV power of 350 W may be required. We review the history of EUV sources for lithography with tin as fuel. We discuss the ideal plasma for tin sources for extreme ultraviolet lithography (EUVL), conditions for a high conversion efficiency of 4% to 5% in 2πsr, and the existence of a repetition rate limit at around 40 kHz. We review the present status reported by EUV source suppliers and the prospects of tin laserproduced plasma as an EUV source for HVM EUVL.

New configuration is presented for ultra-fast at-wavelength inspection of defects on multilayer mask blanks. Key idea are detecting defects in a high NA dark-field observation by using a Schwarzschild objective, sub-micron resolution two-dimensional imaging of mask surface on a detector, and large etendue illumination by using a laser-plasma source. Expected time for inspecting a whole mask is shorter than 2 hours.

No abstract

We investigated the spectral properties of electromagnetic (EM) enhancement of one-dimensional hotspots (1D HSs) generated between silver nanowire (NW) dimers.The EM enhancement spectra were directly derived by dividing the spectra of ultrafast surface-enhanced fluorescence (UFSEF) from single NW dimers with UFSEF obtained from large nanoparticle aggregates, which aggregate-by-aggregate variations in the UFSEF spectra were averaged out. Some NW dimers were found to exhibit EM enhancement spectra that deviated from the plasmon resonance Rayleigh scattering spectra, indicating that their EM enhancement was not generated by superradiant plasmons. These experimental results were examined by numerical calculation based on the EM mechanism by varying the morphology of the NW dimers. The calculations reproduced the spectral deviations as the NW diameter dependence of EM enhancement.Phase analysis of the enhanced EM near fields along the 1D HSs revealed that the dipole-quadrupole coupled plasmon, which is a subradiant mode, mainly generates EM enhancement for dimers with NW diameters larger than ~80 nm, which was consistent with scanning electron microscopic measurements.