A soft-x-ray projection lithography system is developed by the use of multilayer mirrors. To determine the feasibility of a high throughput and a large exposure area, we developed a reduction system that consists of two-aspherical-mirror optics. The figure errors of aspherical mirrors are evaluated by a laser interferometer. The rms aspherical figure errors of concave and convex mirrors are 8.8 and 2.0 nm, respectively, which are not enough to yield a resolution of 0.1 µm. The reduction optics is constructed by adjusting the mirror position to compensate for aberrations, and some trial replications are performed. An exposure area of larger than 10 mm × 0.6 mm with a fine pattern of less than a quarter micrometer is achieved.

A two-mirror telecentric optic has been designed for soft x-ray reduction lithography with high throughput using synchrotron radiation. A resolution of 0.1 μm is achieved at a wavelength of 130 Å with a 15-mm ring field. In the design, aberrations, including distortion, are reduced using aspherical concave and convex mirrors with an ellipsoid surface at a numerical aperture of 0.07. Telecentric imaging is obtained by illuminating a reflection mask using focusing toroidal mirrors. The designed optics achieves a modulation transfer function (MTF) value of over 40% at a spatial frequency of 5000 lines/mm capable of resolving 0.1-μm lines and spaces. The depth of focus is ±1 μm. The distortion is <0.01 μm in the image field. The imaging field is a 12.5-mm radius ring field which enables a 15×15-mm field exposure by the ring-field scanning method. The reduction ratio is 1/5.

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We propose a passive keyless entry system which applies intra body communication and updating scheme. Re cently authentication vulnerability of the system has been reported. And most of attacks eavesdrop on authentication to extract the shared secret. The passive keyless entry system must be safe at least the life time of the vehicle. Our system uses in trabody communication instead of the wireless communication against eavesdropping. Furthermore in case the shared secret is extracted, our system updates the shared secret frequently.In this paper we describe the system design and the demo system.

Extreme ultraviolet lithographic masks with programmed defects on the mask substrates have been imaged to study substrate defects printability. Imaging was performed with a 2-aspherical-mirror system operating at 14 nm wavelength. Results showed that 25 nm thick substrate defects caused observable distortions of resist patterns. Defects of sizes approximately half the minimum resolvable features resulted in 15%-20% variations in resist linewidths. However, since the imaging system was operating at a reduced resolution due to misalignments of the optics, the effect of the defects may have been partially concealed by the phase front distortions caused by mirror misalignments.