Deep, three dimensional lithography with a laser-plasma x-ray source at 1nm wavelength

Abstract

Soft x-rays with 1nm wavelength are used to print 48μm deep structures in chemically amplified resist. A multiple exposure/development technique reduces the x-ray exposure time to a total of 10min when using a compact, laser-plasma x-ray source. The use of an embedded mask generates a true three dimensional structure. Only 2μm thick x-ray masks are used with such soft x-rays. A 2.5THz waveguide cavity is fabricated using this novel process.