Monaico Elena I, Monaico Eduard V, Ursaki Veaceslav V, Honnali Shashank, Postolache Vitalie, Leistner Karin, Nielsch Kornelius, Tiginyanu Ion M
National Center for Materials Study and Testing, Technical University of Moldova, Chisinau MD-2004, Republic of Moldova.
Academy of Sciences of Moldova, Chisinau MD-2001, Republic of Moldova.
Beilstein J Nanotechnol. 2020 Jun 29;11:966-975. doi: 10.3762/bjnano.11.81. eCollection 2020.
A comparative study of the anodization processes occurring at the GaAs(111)A and GaAs(111)B surfaces exposed to electrochemical etching in neutral NaCl and acidic HNO aqueous electrolytes is performed in galvanostatic and potentiostatic anodization modes. Anodization in NaCl electrolytes was found to result in the formation of porous structures with porosity controlled either by current under the galvanostatic anodization, or by the potential under the potentiostatic anodization. Possibilities to produce multilayer porous structures are demonstrated. At the same time, one-step anodization in a HNO electrolyte is shown to lead to the formation of GaAs triangular shape nanowires with high aspect ratio (400 nm in diameter and 100 µm in length). The new data are compared to those previously obtained through anodizing GaAs(100) wafers in alkaline KOH electrolyte. An IR photodetector based on the GaAs nanowires is demonstrated.
在恒电流和恒电位阳极氧化模式下，对暴露于中性NaCl和酸性HNO₃水溶液电解质中进行电化学蚀刻的GaAs(111)A和GaAs(111)B表面发生的阳极氧化过程进行了比较研究。发现在NaCl电解质中进行阳极氧化会导致形成多孔结构，其孔隙率在恒电流阳极氧化下由电流控制，或在恒电位阳极氧化下由电位控制。展示了制备多层多孔结构的可能性。同时，在HNO₃电解质中进行一步阳极氧化可导致形成具有高纵横比（直径400 nm，长度100 µm）的GaAs三角形纳米线。将这些新数据与先前通过在碱性KOH电解质中对GaAs(100)晶片进行阳极氧化获得的数据进行了比较。展示了一种基于GaAs纳米线的红外光电探测器。
