In this paper, dry etching of In<sub>0.8</sub>Al<sub>0.2</sub>As/In<sub>0.8</sub>Ga<sub>0.2</sub>As/In<sub>1-x</sub>Al<sub>x</sub>As (In<sub>1-x-y</sub>Al<sub>x</sub>Ga<sub>y</sub>As) epitaxy material was studied in
BCl<sub>3</sub>/Cl<sub>2</sub>/Ar inductively coupled plasma (ICP). Etching behavior was characterized by varying the BCl<sub>3</sub>/Cl<sub>2</sub>/Ar mixing
ratio, ICP power or DC-bias. The results indicate that, in Cl<sub>2</sub> dominant condition, smooth surfaces are achieved with
mean etch rate exceeding 2 μm/min. As the ratio of BCl<sub>3</sub> increasing, the etch rates decrease monotonously and the
surfaces becomes rougher because of low volatility InCl<sub>x</sub> etch product. ICP power influences the etch rates, and the etch
rates increase monotonously with DC-bias. The result is useful for the fabrication of extended long-wavelength response
optoelectronic InGaAs devices.