Local droplet etching of a vicinal InGaAs(111)A metamorphic layer

We demonstrated nanopit formation by Ga-assisted local droplet etching technique in InGaAs metamorphic layers grown on vicinal GaAs(111)A substrates. We studied nanopit formation depending on the substrate temperature, Ga flux and Ga amount. The etched pits show a highly symmetrical pyramidal shape with an equilateral triangular base and the edges of the triangle are along directions. The observed behavior, in terms of nanopit density, depth and, aspect ratio is well described by a model taking into account the dynamics of the droplet etching process. [Display omitted] •InGaAs metamorphic layers are grown on vicinal GaAs(111)A.•The demonstration of the local droplet etching (LDE) of (111)-oriented surface.•Etched pits have a highly symmetrical pyramidal shape with an equilateral triangular base; the edges of the triangle are along directions.•Nanopits demonstrate good control of the density and size with the growth parameters.•Extended theory of a mass transfer during the LDE process is presented.