MIT Libraries logoDSpace@MIT

MIT
View Item 
  • DSpace@MIT Home
  • MIT Libraries
  • MIT Theses
  • Doctoral Theses
  • View Item
  • DSpace@MIT Home
  • MIT Libraries
  • MIT Theses
  • Doctoral Theses
  • View Item
JavaScript is disabled for your browser. Some features of this site may not work without it.

Hydrothermal synthesis of zinc oxide nanowire arrays for photovoltaic applications

Author(s)
Cheng, Jian Wei Jayce
Thumbnail
DownloadFull printable version (20.76Mb)
Alternative title
Hydrothermal synthesis of ZnO nanowire arrays for photovoltaic applications
Other Contributors
Massachusetts Institute of Technology. Department of Materials Science and Engineering.
Advisor
Silvija Gradečak
Terms of use
MIT theses are protected by copyright. They may be viewed, downloaded, or printed from this source but further reproduction or distribution in any format is prohibited without written permission. http://dspace.mit.edu/handle/1721.1/7582
Metadata
Show full item record
Abstract
Zinc oxide (ZnO) nanowires with excellent crystal quality can be grown vertically aligned from a substrate using hydrothermal synthesis, a low-cost, scalable process that is compatible with many semiconductor processing techniques. However, precise control over nanowire array dimensions such as nanowire spacing, diameter, length, and alignment, which is important for optoelectronic device applications, has proven elusive due to lack of understanding regarding fundamental aqueous growth mechanisms at the nanoscale. Here, we utilize electron-beam lithography to template ZnO seed layers, demonstrating that seed layer engineering via judicious choice of seed deposition conditions and annealing can yield well-aligned nanowire arrays with single nanowire spatial precision on a variety of device relevant substrates. Subsequently, we use bottom-up patterning techniques and investigate the competition between diffusive transport and surface reaction in hydrothermal growth to achieve control over nanowire spacing and enhanced nanowire array uniformity over length scales suitable for photovoltaic (PV) device fabrication. By analyzing the role of temperature, concentration, and areal seed density on the balance between diffusion vs. reaction rates at the solution-nanowire interface, we show that the c-facet grows via the direct incorporation mechanism. With this knowledge, we use additives to shift the nanowire growth system into a reaction-limited regime, making nanowire growth rate independent of the patterned template. As a consequence, we achieve ZnO nanowire array uniformity that is critical for device applications.
Description
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Materials Science and Engineering, 2016.
 
Cataloged from PDF version of thesis.
 
Includes bibliographical references.
 
Date issued
2016
URI
http://hdl.handle.net/1721.1/108216
Department
Massachusetts Institute of Technology. Department of Materials Science and Engineering
Publisher
Massachusetts Institute of Technology
Keywords
Materials Science and Engineering.

Collections
  • Doctoral Theses

Browse

All of DSpaceCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsThis CollectionBy Issue DateAuthorsTitlesSubjects

My Account

Login

Statistics

OA StatisticsStatistics by CountryStatistics by Department
MIT Libraries
PrivacyPermissionsAccessibilityContact us
MIT
Content created by the MIT Libraries, CC BY-NC unless otherwise noted. Notify us about copyright concerns.