【Others Papers】Step-and-terrace surface formation on (001) β-Ga₂O₃ by wet etching using 2.38 wt% tetramethylammonium hydroxide (TMAH) lithographic developer

      Researchers from the National Institute for Materials Science have published a dissertation titled "Step-and-terrace surface formation on (001) β-Ga₂O₃ by wet etching using 2.38 wt% tetramethylammonium hydroxide (TMAH) lithographic developer" in Japanese Journal of Applied Physics.

Abstract

      Wet etching of (001) β-Ga₂O₃ was performed using a standard lithographic developer—an aqueous solution of 2.38-wt% tetramethylammonium hydroxide (TMAH)—at moderate temperatures of 25 and 40 °C. At both temperatures, the chemically-mechanically polished surfaces, which consisted of terraces with numerous pits and, in some samples, one- to two-monolayer-high islands, were gradually smoothed through a layer-by-layer etching process. This resulted in a well-defined step-and-terrace surface morphology characterized by pit-free, atomically flat terraces and monolayer steps (~0.56 nm). These findings indicate that developer-based etching offers a simple yet highly effective approach for preparing (001) β-Ga₂O₃ surfaces for subsequent epitaxial growth or device fabrication.

DOI：

https://doi.org/10.35848/1347-4065/adf380