Correlations between the surface morphology and electronic properties of porous multilayer structures with quantum InGaAs layers

The conducting properties of the porous two-dimensional InGaAs layers embedded in GaAs or InAlAs porous dielectric matrix are discussed. The influence of the electrochemical etching time of samples, their porosity and surface morphology on the optical and electrophysical characteristics of the structures with a low-dimensional electron gas has been investigated. The change of a surface structure morphology during an etching process was studied by a scanning probe microscopy (SPM). Using this method we estimated a range of a porosity, width and depth of pores formed in a sample as function of the time etching. We considered both the InGaAs layers located nearest a sample surface when the pores intersected a layer plane, and a case for the InGaAs layers lying under a layer of a porous material. In all these cases the precise correlation between a surface morphology and a conductivity of a two-dimensional electron gas in a layer was traced.