This thesis describes the design, growth and x-ray characterization of normal incidence multilayer x-ray mirrors. The mirrors are intended as condenser optics for soft x-ray microcsopy in the water window.

A droplet-target laser-plasma soft x-ray source has been developed to be used in a compact soft x-ray microscope. The microscope operates at the wavelength λ=3.374 nm, corresponding to the C VI emission line from a laser plasma x-ray source. Due to the isotropic nature of laser-produced plasma sources, large shaped, normal incidence condenser mirrors collecting x-rays over a large solid angle from the source, and focusing them onto the specimen, are required.

Since ordinary refractive optics cannot be utilized in this wavelength range, so called multilayer interference structures, based on diffraction and reflection, have been developed.

The multilayers were designed to have the maximal theoretical normal reflection of the first and second order of λ=3.374 nm using the IMD computer software. The realization of the multilayers were accomplished using ion-assisted dual target DC magnetron sputtering. To characterize the multilayers and improve the deposition process hard x-ray reflectivity was used. Further, at-wavelength (λ=3.374 nm) reflectivity measurements were carried out using a reflectometer based on the laser-plasma source. In addition, measurements have been performed using synchrotron radiation at the Advanced Light Source (ALS) in Berkeley.