FABRICATION OF CYLINDRICAL, MICROCELLULAR FOAM-FILLED TARGETS FOR LASER-DRIVEN EXPERIMENTS

Small, open ended, parylene cylinders of 150 μm diameter, 250 μm length, and 10 μm wall thickness are manufactured and filled with solutions of acrylate monomers which are polymerised in situ with UV light to produce gels. These gels are then precipitated in a nonsolvent such as methanol and dried in a critical point drying apparatus to produce foam-filled parylene cylinders for use in laser-driven plasma experiments. The foams have densities in the range of 20 to 200 mg cm -and cell sizes of up to 1 μm, fill the cylinders completely, do not shrink during the drying process and do not require subsequent machining. © 1990, American Vacuum Society. All rights reserved.