III-V semiconductor nanowire growth: does arsenic diffuse through the metal nanoparticle catalyst?
The synthesis of III-V semiconductor nanowires (NWs) is based on the delivery of atoms from a vapor phase to a catalytic metal nanoparticle (NP). Although there has been extensive work on such systems, the incorporation pathways of group V atoms remain an open issue. Here, we have performed a detailed structural and chemical analysis of the catalyst NP in NWs where we switch the V atomic element during growth (heterostructured InP/InAs/InP NWs). Our experimental results indicate a group V pathway where these atoms actually diffuse through the catalytic NP by formation of a stable phase containing As under growth conditions. We have observed distinct NW growth behavior within a narrow temperature range (30 degrees C) suggesting a transition between vapor-liquid-solid and vapor-solid-solid growth modes.
Tizei
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LH
Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas-UNICAMP, C P 6165,13083-970 Campinas, SP, Brazil. ltizei@ifi.unicamp.br
Chiaramonte
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T
Ugarte
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Cotta
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