Fabrication of NaCl, KBr and CsJ crystals with 5-30 μm thickness for channeling studies

The process of preparing thin NaCl, KBr and CsJ crystals useful in particle channelling investigations is described. The first process step is piercing out (for NaCl and KBr) or sawing out (for CsJ) 1 to 1.5 mm thick plates. The obtained plates are mechanically ground and polished to a thickness of between 150 and 200 microns. The plates are then dissolved in an etching-polishing agent to a thickness between 5 and 30 mc. The etching agent is a mixture of ethyl alcohol and water. By varying the proportional content of water in ethyl alcohol the etching rate can be controlled. After etching the crystals are dried on filtration paper and then calcined at a temperature about 20 to 50 deg below their melting point. The final crystals are 5 to 30 microns thick and may be used as test samples in angle and energy measurements in particle channelling processes