Fundamentals of III-V Semiconductor Electrochemistry and Wet Etching Processes: Br_2 Etching Properties onto InP

摘要

Etching mechanism of InP in HBr/Br2 solution, is investigated correlating electrochemical characterization, XPS analyses, Indium dosage by GF-AAS, SEM analysis of cross sectional shapes of etching features. We observed the opposite electrochemical behavior toward reduction of Br_2 for n and p InP in the dark. The electrochemistry supports a description of the etching similar to the GaAs one, supposing a "chemical model" governs the process. Nevertheless XPS analyses of surface after etching shows that the etching implies oxidation processes that can only considered as resulting from the etching mechanism. So side oxidation process including hole injection contribution in the Br_2 reduction can be proposed opening a new element for discussion of the model that describe the etching properties of halogen oxidizing species as Br_2.