Soft X‐ray contact microscopy with nanosecond exposure times

SUMMARY High resolution (better than 20 nm) contact micrographs have been produced with exposure times of about a nanosecond. The illuminating source was a short‐lived carbon plasma produced by focusing a single short (∼1 ns) 100 J pulse from the Vulcan laser at the Rutherford Appleton Laboratory (RAL) to a 300 μm spot on a graphite target. This plasma emits strongly in the soft X‐ray region, particularly at the CVI (3.37 nm) and CV (4.03 nm) lines. The specimens were behind a 100 nm thick Si3N4 window, at atmospheric pressure in an environmental cell. The images of diatoms recorded on X‐ray resist showed features down to the limit of resolution of the SEM used to view the developed resist, which was about 20 nm.