Clean and damage-free GaAs surfaces prepared by ultrasonic running deionized water treatment

Abstract GaAs(001) surfaces treated with ultrasonic running deionized water (URDIW), after being etched by H 2 SO 4 or NH 4 OH were examined by using X-ray photoelectron spectroscopy (XPS) and reflection high-energy electron diffraction (RHEED), XPS analysis revealed that the arsenic and gallium oxides on chemically etched surfaces were completely removed by the URDIW treatment. RHEED observation indicated that the H 2 SO 4 -etched GaAs surface shows a streaky (2×1) surface reconstruction pattern at 360°C and that the NH 4 OH-etched surfaces show a (2×4) surface reconstruction pattern at 310°C. These experimental results indicate that chemically clean GaAs surfaces with little damage can be produced by URDIW treatment and that the stoichiometry of a URDIW treated surface can be controlled by varying the etching solutions.