Layer etching of mica nanosheets using a focused electron beam

Mica, a cleavable layered material, is a single-crystalline phyllosilicate having unique electronic and mechanical properties such as a wide bandgap and tolerance to strong electric fields and high temperatures, and is applicable to flexible electronics. This paper describes the nanometer-level layer etching of mica nanosheets exfoliated from artificially synthesized phlogopite and affixed on substrates, using a focused electron beam for fine-pattern fabrication of the nanosheets. The dependence of the etching on the irradiation time, beam current, and beam energy is examined. The etching process was analyzed by in situ scanning Auger electron spectroscopy and microscopy. The layer etching of mica nanosheets leads to the micro- and nano-fabrication of mica-based two-dimensional heterodevices.