Power loading limitations in soft x-ray projection lithography.

Soft x-ray projection lithography (SXPL) is an attractive technique for the fabrication of high-speed, high-density integrated circuits. In an SXPL stepper, the x-ray imaging mirrors consist of multilayer coatings deposited onto high precision substrates. The stepper is intended to fabricate ultra-high spatial-resolution structures with a minimum feature size of <0.

Wavelength considerations in soft-x-ray projection lithography.

The choice of the operational wavelength for a soft-x-ray projection lithography system affects a wide variety of system parameters such as optical design, sources, resists, and multilayer mirrors. Several system constraints limit the choice for the operational wavelength. In particular, optical imaging requirements place an upper limit and throughput issues place a lower limit on the wavelength selection.

Front-end design issues in soft-x-ray projection lithography.

We present a protocol for the design of an illumination system (front end) for a soft-x-ray projection lithography tool. The protocol is illustrated by specific front-end designs. The most complete design analysis is for a laser-driven system.

Undulator radiation for at-wavelength interferometry of optics for extreme-ultraviolet lithography.

Techniques are described for at-wavelength interferometry of multilayer coated optics designed for use in extreme-ultraviolet lithography. Broadly tunable undulator radiation, which covers the spectral region from 45 to 400 A, is described. The coherent power available at these wavelengths is described, and several types of interferometer that might be suitable at these short wavelengths are also described.

Radiation hardness of molybdenum silicon multilayers designed for use in a soft-x-ray projection lithography system.

A molybdenum silicon multilayer is irradiated with 13.4-nm radiation to investigate changes in multilayer performance under simulated soft-x-ray projection lithography (SXPL) conditions. The wiggler-undulator at the Berlin electron storage ring BESSY is used as a quasi-monochromatic source of calculable spectral radiant intensity and is configured to simulate an incident SXPL x-ray spectrum.