Inductively coupled plasma etching of In1-x-yAlxGayAs in BCl3/Cl2/Ar

In this paper, dry etching of In0.8Al0.2As/In0.8Ga0.2As/In1-xAlxAs (In1-x-yAlxGayAs) epitaxy material was studied in BCl3/Cl2/Ar inductively coupled plasma (ICP). Etching behavior was characterized by varying the BCl3/Cl2/Ar mixing ratio, ICP power or DC-bias. The results indicate that, in Cl2 dominant condition, smooth surfaces are achieved with mean etch rate exceeding 2 μm/min. As the ratio of BCl3 increasing, the etch rates decrease monotonously and the surfaces becomes rougher because of low volatility InClx 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.