Dimensional Tailoring of Hydrothermally Grown Zinc Oxide Nanowire Arrays

TitleDimensional Tailoring of Hydrothermally Grown Zinc Oxide Nanowire Arrays
Publication TypeJournal Article
Year of Publication2016
AuthorsCheng, JJ, Nicaise, SM, Berggren, KK, Gradecak, S
JournalNano Letters
Volume16
Issue1
Pagination753 - 759
Date Published2016/01//
Abstract

Hydrothermally synthesized ZnO nanowire arrays are critical components in a range of nanostructured semiconductor devices. The device performance is governed by relevant nanowire morphological parameters that cannot be fully controlled during bulk hydrothermal synthesis due to its transient nature. Here, we maintain homeostatic zinc concentration, pH, and temperature by employing continuous flow synthesis and demonstrate independent tailoring of nanowire array dimensions including areal density, length, and diameter on device-relevant length scales. By applying diffusion/reaction-limited analysis, we separate the effect of local diffusive transport from the c-plane surface reaction rate and identify direct incorporation as the c-plane growth mechanism. Our analysis defines guidelines for precise and independent control of the nanowire length and diameter by operating in rate-limiting regimes. We validate its utility by using surface adsorbents that limit reaction rate to obtain spatially uniform vertical growth rates across a patterned substrate.