CH_4/H_2 plasma etching of IV-VI semiconductor nanostructures

摘要

We investigate plasma etching of IV-VI nanostructures using a CH_4/H_2 gas mixture. For various IV-VI compounds we find that the etch rate decreases with the energy band gap. For Pb_(1-x)Eu_xTe, in contrast, the etch rate decreases drastically with increasing Eu content. This property can be utilized for selective etching. Furthermore, we demonstrate IV-VI quantum wires with vertical side walls by a combination of laser holography and CH_4/H_2/Ar plasma etching.