Structuring of GaAs. I. Chemical dry etching: Temperature and chlorine pressure dependence of etch rates

Abstract

Articles you may be interested inDirect integration of subwavelength structure on a GaAs solar cell by using colloidal lithography and dry etching process J. Vac. Sci. Technol. B 31, 031202 (2013); 10.1116/1.4798410 Micro-photoluminescence characterizations of GaInAsP/InP single quantum wires fabricated by dry etching and regrowthEtch rates of chemical dry etching ͑CDE͒ of GaAs͑100͒ were determined experimentally in the range from 220 to 475 K and dichlorine pressures up to 0.64ϫ10 Ϫ3 mbar. Model-based understanding of the CDE process is proposed to close the gap between experimental data derived from different setups. With the aid of pseudospecies and carefully selected simplifications all experimental features can be quantitatively explained. The thermal desorption kinetics of dichlorine from the GaAs͑100͒ surface was derived successfully from etch rate data. This model paves the road for an extension to include the ion beam impact influence found in chemically assisted ion beam etching.

Modeling of the chemically assisted ion beam etching process: Application to the GaAs etching by Cl2∕Ar+

“…The effect of this parameter on the etching is difficult to control because of the competition between Cl 2 dissociative adsorption, Cl 2 desorption, and the chemical etching of GaCl x . As in the chemical etching of GaAs, 23 we observe that the etching rate variation with substrate temperature presents a maximum T M . 23 The increase of the chlorine pressure ͑corresponding to the increase of the chlorine flow rate 20,21 allows to increase the etching rate.…”

“…21,23 The etching rate on the surface element i is given as 21,23 The etching rate on the surface element i is given as…”

“…23 The Cl 2 molecule that does not adsorb on the ith surface element is reflected toward other surface elements. 23 The Cl 2 molecule that does not adsorb on the ith surface element is reflected toward other surface elements.…”

“…Experimental study concerning the pure chemical etching was carried out by Dienelt et al 23 Figure 5 presents the chemical etching of GaAs as a function of temperature for different Cl 2 pressure values. It allows to activate the adsorption and the desorption process on the etched surface.…”

Chemically assisted ion beam etching of GaAs by argon and chlorine gases: Experimental and simulation investigations

“…In Table I, we present our estimated surface energies and those determined by Dienelt et al 11 The physical sputtering yield of the uncovered GaAs surface by chlorine is given as a function of the ion energy and determined by using the TRIM code 13 These values are estimated by minimizing the difference between the experimental and the simulation data concerning the etching rate versus the substrate temperature.…”