Laser plasma was generated by a 1GW iodine photodissociation laser (λ=1.315㎛, E=12.7J) whose output beam was focused on a molybdenum target surface. Molybdenum is known as an efficient target material for the soft X-ray region. The size of a soft X-ray source was measured to be 544㎛ by using a pinhole camera. The resist was coated by spin coating and its thickness was about 1㎛. The experiment was conducted in the vacuum chamber under $10^{-5}$ Torr and several tens of laser shooting were necessary for sufficient exposure to the PBS resist. A specimen was put directly on the resist and located at a distance of 3cm from the X-ray source. Between the resist and a specimen, aluminium was coated about 0.1㎛ thickness for the X-ray filter to cut off the visible and ultraviolet lights. The replicas of a spider's tread, a red blood cell, an E.coli, and an onion's skin were obtained by PBS resist and were analyzed by SEM. Two main effects of limitation in resolution, source size and Fresnel diffraction, are mentioned and compared with the experimental result. In this experiment, a resolution better than 1000A could be obtained.
