*********************************
There is now a CONTENT FREEZE for Mercury while we switch to a new platform. It began on Friday, March 10 at 6pm and will end on Wednesday, March 15 at noon. No new content can be created during this time, but all material in the system as of the beginning of the freeze will be migrated to the new platform, including users and groups. Functionally the new site is identical to the old one. webteam@gatech.edu
*********************************
MSE PhD Proposal - Ken Pradel
Friday, September 19th from 3-5pm
IPST Rm 114
Committee:
Dr. ZL Wang (MSE, advisor)
Dr. Benjamin Klein (ECE)
Dr. Elsa Reichmanis (ChBE)
Dr. Preet Singh (MSE)
Dr. Christopher Summers (MSE)
Title: Antimony Doped p-type Zinc Oxide for Piezotronics and Homojunctions
Abstract
Since the term was first coined in 2007, the field of piezotronics has grown to envelop numerous applications in tactile sensing and energy generation. The key to piezotronics has been coupling a material’s piezoelectric and semiconducting properties to tune carrier transport through the material. This provides a novel alternative to the electrically induced field effect used in conventional electronics. An expansion of the concept of piezotronics is the piezophototronic effect, where the piezopotential is used to tune the materials optoelectronic properties, for applications such as enhanced light emitting diodes and solar cells. For the vast majority of these studies, the material of choice is naturally n-type ZnO nanowires as they are single crystalline and easy to synthesize. However, there have been few studies on the piezoelectric and piezotronic properties of p-type materials. As a II-VI semiconductor, the obvious candidates for doping ZnO are either group I elements such as Li or Na, or group V elements like N or P. Part of the difficulty in p-type doping ZnO is the formation of low energy compensating donors such as hydrogen interstitials, or oxygen vacancies. If stable p-type ZnO can be realized, then it is possible to produce homojunction based devices with more complex piezotronic functionality. Based on the above mentioned challenges, the goal of this PhD proposal is to synthesize stable p-type ZnO in order to investigate its piezoelectric and piezotronic properties. Using antimony doped p-type ZnO; I will demonstrate that the piezotronic effect is universal to all piezoelectric semiconductors regardless of carrier type. Furthermore, I will investigate different p-n homojunction architectures, and how the junction and the material’s piezoelectric properties interact as a result.
