Electrochemical nanostructuring of (111) oriented GaAs crystals: from porous structures to nanowires

• Elena I. Monaico,
• Eduard V. Monaico,
• Veaceslav V. Ursaki,
• Shashank Honnali,
• Vitalie Postolache,
• Karin Leistner,
• Kornelius Nielsch and
• Ion M. Tiginyanu

Beilstein J. Nanotechnol. 2020, 11, 966–975, doi:10.3762/bjnano.11.81

• previously obtained through anodizing GaAs(100) wafers in alkaline KOH electrolyte. An IR photodetector based on the GaAs nanowires is demonstrated. Keywords: anodization; crystallographically oriented pores; gallium arsenide (GaAs); nanowires; neutral electrolyte; photocurrent; porous GaAs; Introduction

• number of tilted pores. One can conclude that etching in HNO3 electrolyte suppresses the nucleation of tilted pores as compared to anodization in HCl or H2SO4 electrolyte, resulting in the fabrication of non-porous GaAs nanowires, which are better suitable for photodetector applications. High-aspect

• needed for such structures, which makes photolithography challenging [38]. Conclusion This study demonstrates possibilities to produce porous GaAs structures with a controlled degree of porosity through the anodization of GaAs(111) wafers in a neutral, environmentally friendly NaCl electrolyte. Porous