A Comparison of Chemical Bath Deposition of CdS from a Batch Reactor and a Continuous-Flow Microreactor

Abstract

In this paper, we report a comparison between CdS deposition by a conventional batch reactor and a newly developed continuous-flow microreactor. This microreactor setup makes use of a micromixer for efficient mixing of the reactant streams and helps in controlling the homogeneous reaction before the solution impinges on a substrate. Transmission electron microscopy analysis indicated that an impinging flux without the formation of nanoparticles could be obtained from this reactor at a short residence time. The surface morphology of the deposited films clearly indicated an improvement of film smoothness and coverage over films deposited from a batch process. Highly oriented nanocrystalline CdS films were obtained from the continuous-flow microreactor in contrast to poor crystalline films from the batch process. This new approach could be adopted for the deposition of other compound semiconductor thin films at low temperatures using a solution-based chemistry with improved control over the processing chemistry.

Enhancement of pool-boiling heat transfer using nanostructured surfaces on aluminum and copper

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“…Further, Oregon State University researchers has demonstrated the heterogeneous nucleation and growth of nanostructured surfaces from short-life reaction chemistries leading to shorter cycle times with improved energy and material efficiencies [20,21]. Overall, OSU has demonstrated significant economical and environmental advantages of MAND™ processes over existing vapor-phase deposition techniques [22,23]. From a detailed literature search, MAN-D™ type approaches have not been systematically explored to date for thermal applications.…”

Structure, Morphology, and Optical Properties of the Compact, Vertically-Aligned ZnO Nanorod Thin Films by the Solution-Growth Technique

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