Structure and properties of porous GaAs

In this paper we report the first results obtained in the study on the properties of porous GaAs (P-GaAs) produced by electrochemical etching in electrolytes on the basis of hydrofluoric acid. As the initial material we used monocrystalline n- and p-type (100)GaAs substrates Te- and Zn-doped to 2*10 18 cm -3 and 6*10 18 cm -3 , respectively. The substrates were subjected to chemical-mechanical and diamond-paste polish. Etching was performed in an electrolytic cell with a platinum cathode in the galvanostatic regime with anode current densities ranging from 5 to 150 mA/cm 2 . We were interested in P-GaAs layers with thicknesses from 0.5 to 50 micrometers. The methods used in the study of P-GaAs samples included x-ray diffractometry, electron microscopy, x-ray microanalysis, secondary ion-mass spectroscopy, electrochemical C-V profiling and photoluminescence.