GaAs manufacturing processes conditions for micro- and nanoscale devices

High aspect-ratio etchings are a key aspect of the fabrication of III-V semiconductor devices. The increasing demand for diverse geometries with various characteristic lengths (from the micro- to the nano-meter scale) requires the constant development of new etching recipes. In this article, we demonstrate a versatile mask-plasma combination for micro- and nanofabrication of GaAs substrate using an Inductive Coupled Plasma Reactive Ion Etching (ICP-RIE) system. We identify five recipes at 25 degrees C, with high selectivity, and apply them on one photoresist (AZ4562) and two hard (chromium and nickel) masks. The optimized etching plasma chemistry (BCl3/Cl-2/Ar/N-2) shows a pattern transfer on GaAs with a high rate (>= 5.5 mu m/min), a high anisotropy, a high selectivity (>4:1 with photoresist mask, and >50:1 with hard masks), a good etch surface morphology, and smooth sidewalls profile (>88 degrees). Herein, we detail the requirements definition, the engineering processes with detailed recipes, the verification, and validation of three device geometries (ridges, cylinders, and nano pillars). The presented results can be valuable for a wide range of applications from the microscale to the nanoscale, and are compatible with a manufacturing process using only a single commercial ICP-RIE tool with two chambers dedicated, respectively, for metallic masks and photoresist mask.