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A high-brightness electron accelerator system with a photocathode RF gun and an all-solid stable laser for the photocathode was installed, and a commissioning test was performed to generate short-pulse X-ray beams by the Thomson scattering method. Electron energy was boosted by a linear accelerator (linac) up to 14 MeV. Energy dispersion of the electron beams was measured to be 0.7% (rms). The normalized emittance of the electron beam was 4 πmm-mrad with a 0.4 nC bunch charge. The electron beam size at the interaction point, where the electron beams and high peak power laser light interacted, was measured to be 100 µm (rms). Good stability in the spatial and temporal domains was also obtained.

We present recent results of our laser-produced plasma light source development for next-generation lithography. The plasma target of the extreme ultraviolet (EUV) source system is a liquid xenon jet and the driver laser is a 600 W Nd:YAG laser operating at a repetition rate of 10 kHz. A EUV output power of 2.2 W at 13.5 nm (2% bandwidth, 2π sr) having a stability of 0.72% (1σ, 50-pulse moving average) has been achieved. Related to future collector mirror lifetime considerations, fast ions from the laser-produced plasma have been characterized by time-of-flight (TOF) measurements. Using a low repetition rate 8-ns, 100-mJ Nd:YAG laser Xe+ to Xe6+ ions were observed with Xe2+ being the main charge state. In addition, the effects of fast ions on Mo/Si multilayer mirrors have been studied using a Xe ion gun. Ion sputtering of the multilayer structure is the main damage mechanism but layer boundary mixing and surface roughness increase are also observed.

Short-pulse X-ray generation was demonstrated in a scattering experiment between a 4 ps electron beam and a 10 ps Nd:YLF laser beam. The beams interacted at 0° and 90°. The X-ray signal was measured using a microchannel plate. Maximum X-ray energy was analytically estimated to be 3.55 keV in the 0° interaction and 1.77 keV in the 90° interaction with a pulse duration of 4 ps for both interactions. Measured X-ray intensities exhibited good linearity with the incident laser light pulse energy for both scattering configurations. The measured X-ray intensity was compared with the intensity analyzed from the beam sizes and energies of both beams. The intensities matched and were of the order of 104 photons in the 0° interaction.

We have obtained clear experimental evidence for the oscillatory magnetoresistance effect in a two-dimensional electron gas under the influence of a spatially modulated magnetic field, which has been theoretically predicted. The magnetoresistance curve contains an oscillatory component due to the magnetic modulation as well as one due to the potential modulation, and their relative amplitudes can be changed by adjusting the gate bias.

Secondary electron (SE) imaging with a high-resolution ultrahigh-vacuum scanning electron microscope (UHV-SEM) has been applied to the observation of the Au/Si(111) system. Domains of the 5×2-Au or √3×√3-Au structure partially covering a Si(111)-7×7 surface are clearly observed. Domains of 5×2-Au formed by Au deposition onto a substrate held at ∼870 K show threefold elongation corresponding to three equivalent kinds of domains rotated 120° to each other. On the other hand, 5×2-Au regions formed by partial Au desorption by heating at ∼1270 K from an entirely covered surface display larger size without such elongation. Granular clusters, a few nm in size, of Au formed by deposition approximately at room temperature, and large three-dimensional islands formed in the Stranski-Krastanov growth mode are also clearly imaged.

The influence of fictional constant and hardness of a fictional material of an ultrasonic motor was investigated. Performance characteristics of the ultrasonic motor are dominated by the frictional constant of the frictional material. In particular, the velocity of the motor is in proportion to the square root of the frictional constant. Optimum range of hardness for the frictional material can be obtained experimentally.