Self-formation of lead telluride nanostructures during argon plasma etching of single-crystal wafers

Abstract

In this work we report a phenomenon of PbTe nano- and microstructure selfformation that takes place during dry etching of lead telluride (111)-oriented single-crystal wafers with 4 at.% excess tellurium in RF high-density low-pressure inductively coupled argon plasma. Using scanning electron microscopy and energy dispersive X-ray spectroscopy investigations it is established that during the plasma treatment high sputtering rates are accompanied by active redeposition processes on crystal surface and on the inner side of the Si etching mask resulting in a nanostructure arrays self-formation via vapour-liquid-solid mechanism.