Extreme ultraviolet generation

According to IC industry s roadmap, the next generation lithography will probably use exposure at 13.4 nm, in the extreme ultraviolet (EU V), for 22 nm feature size. Due to the huge absorbance of any material at this wavelength, the optics will consist of reflective mirrors, without any lenses involved. The big challenges at 13.4 nm are the new materials for photoresists and the low output of the EUV light sources. 

Some of the applications of third- and higher-order frequency conversion are given in Table VII. The th harmonic generation is used to produce radiation at a frequency that is q times the incident frequency. The most commonly used interaction of this type is third-harmonic conversion. It has been used to produce radiation at wavelengths ranging from the infrared to the extreme ultraviolet. Third-harmonic conversion of radiation from high power pulsed lasers such as CO2, Ndiglass, Nd YAG, ruby, and various rare-gas halide and rare-gas excimer lasers has... 

G. Z. Zhang, D. W. Tokaryk, B. P. Stoicheff, K. Hakuta. Nonlinear generation of extreme-ultraviolet radiation in atomic hydrogen using electromagnetically induced transparency. Physical Revew A 1997 Dec 2 56(1) 813-819. 

For ion TOF measurement a probe laser was used to ionize reaction products in the reaction zone. The (1 + F) resonance-enhanced multiphoton ionization (REMPI) method was adapted for H-atom detection. The necessary vacuum ultraviolet (VUV) radiation near 121.6 nm (for Lyman-a transition) can readily be generated by a frequency-tripling technique in a Kr cell.37 The sensitivity of this (1 +1 ) REMPI detection scheme is extremely high owing to the large absorption cross-section of Lyman-a transition,... 

Microtubules are used to cover relatively long distances in the cell. Therefore, the short distance between the cell surface and the early endosomes does not require microtubules (94,136). They are involved in the later steps in endocytosis early endosomes accumulate endocytic material for about 10 minutes and then generate transport vesicles (0.5 pm in diameter), which will be taken to the cell center with a relatively high traveling speed of Ipm/sec (with velocities of up to 2.5pm/sec) (95,137). These transport vesicle move on microtubule-tracks to the cell center (and to the ly sosome) (94). When performing live cell imaging studies, it should be kept in mind that microtubules are extremely sensitive to ultraviolet light, which causes their polymerization. 

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