Fabrication of Al/LiF Composite Dual-step Target Used in Quasi-isentropic Compression Experiment by Laser Loading

The fabrication technique for Al/LiF composite dual-step target used in quasi-isentropic compression experiment was described. The two 10 μm high steps were processed by diamond turning technology in the surface of the 1.5 mm LiF crystal. The high-density Al film with dozens of micron thickness was coated by electron beam evaporation, and turned into a flat aluminized surface through the diamond turning process. A high-quality Al/LiF composite dualstep target was eventually completed with an evaporated antireflection film (the residual reflectivity was less than 1%) on the other side of the LiF crystal. The target parameters were measured by NT1100 white light interferometer, electron densimeter, electron spectroscopy, XRD and SEM for sensitivity analysis.