We report nanometer-sized silicon (Si) crystallites prepared by excimer laser ablation in constant pressure inert gas ambient. Size distribution of the Si ultrafine particles depends on the pressure of inert gas ambients. The relation between the average size and the ambient pressure can be explained by an inertia fluid model. It is verified that the size of the Si ultrafine particles is ∼3 nm and greater in diameter. Furthermore, crystallinity of the nanoscale ultrafine particles is crystalline similar to that of bulk Si.

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The output properties of hydrogen light sources and the resist parameters, such as spectral sensitivity and absorption coefficient, in the vacuum-ultraviolet (VUV) region were investigated. A very low exposure energy of about 1 mJ/cm2 was obtained by employing a very thin polymethyl methacrylate film and the VUV light of hydrogen microwave discharge. Contact photolithography using a Si/MgF2 mask and a trilayer resist system showed that submicron patterns as small as 0.2 µm had been replicated at an exposure time of under 30 s.

Reactive ion-beam etching (RIBE) of InP with Cl2 at room temperature has been studied by varying the ion extraction voltage and the gas pressure. The sputtering yield is found to increase linearly with the ion extraction voltage above a threshold voltage. RIBE with a higher Cl2 gas pressure is dominated by the chemically reactive etching, and offers a higher etch rate and a smoother surface. Smooth surfaces with low concentrations of residual Cl atoms are obtained under the ion extraction voltage of 400 V and Cl2 gas pressure of 2.5×10-3 Torr.

We classify super-symmetric solutions of the minimal N = 2 gauged Euclidean supergravity in four dimensions. The solutions with an anti-self-dual Maxwell field give rise to anti-self-dual Einstein metrics given in terms of solutions to the SU (∞) Toda equation and more general three-dimensional Einstein-Weyl structures. Euclidean Kastor-Traschen metrics are also characterized by the existence of a certain supercovariantly constant spinor.