Fabrication of triangular pits in barium fluoride single crystals by localized electronic excitations

Ion beam technology is considered as one of the most effective and unique techniques for materials engineering. Here, we show that the selective chemical etching is used successfully for the fabrication of pyramidal etch pits by revealing the ion-induced damage in the surface and below surface regions of barium fluoride single crystals. The size of ion-induced pits is increasing by etching the ion impacted zones for longer time. Moreover, the types of the induced defects are probed using optical absorption spectroscopy. The presented findings are discussed in terms of the peculiarities of ion energy deposition as well as the comparison with the induced structures using different type of ions, namely slow highly charged ions. Furthermore, they might be of importance in today's nano and microelectronics applications, where the fabrication of size-controlled surface structures is of high necessity.