Laser produced plasmas have been shown to be excellent sources for applications in the XUV and soft X-ray spectral region. We are using a 550 mj, 25 ns (FWHM) ND:YAG laser operating at a repetition rate of 10 Hz to produce plasmas above rotatable solid targets. The focal spot of the laser beam with a 31 cm lens was measured to be 170 μm (approximately twice the diffraction limit), using a diode array having a 170 μm resolution. Broadband output in the soft X-ray region was studied using a windowless PIN photodiode with an A1203 surface covered with a polyethylene filter with transmission between 44 Å and 120 Å. Results are presented for the source’s soft X-ray intensity for several elements as a function of laser energy, focus and driving wavelength, as are preliminary results using the source for high resolution spectroscopy and for soft X-ray lithography.
Overcoming x-ray tube small focal spot output limitations for high resolution region of interest imaging