Scanning Electrochemical Microscope
نویسنده
چکیده
A scanning electrochemical microscope (SECM) was used as an analytical tool to study the etching of GaAs surfaces. Hole injection from several eledrogenerated oxidants to n-type, p-type, and undoped GaAs was examined by the feedback mode of the SECM. Assignment of the process as a hole injection from the oxidized form of the redox couple into the valence band and assignment of the energy of the valence band edge in the semiconductor were made by studying the behavior of the feedback current at various pHs and with different redox couples. The nature of the dopant strongly affected the etching process. n-GaAs and undoped GaAs were etched by using the feedback mode while p-GaAs was completely resistive toward etching. The differences between n-GaAs and p-GaAs are explained in terms of semiconductorelectrolyte interactions.
منابع مشابه
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The first papers related to the scanning electrochemical microscopy (SECM) were published in the nineties of the 20th century [1, 2]. This technique is based on the scanning of the studied surface by ultramicroelectrode (UME) and electrochemical analysis of surface [1]. Such technique gives us an electrochemical picture of the surface. SECM employs an UME probe (tip) to induce chemical changes ...
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