Skip to Main Content
 

Global Search Box

 
 
 
 

Files

File List


NicholasMinutilloDissertation.pdf (5.1 MB)

ETD Abstract Container

Abstract Header

The Growth and Characterization of Gallium Arsenide Nanowire Structures by Metal Organic Chemical Vapor Deposition

Minutillo, Nicholas G.
http://rave.ohiolink.edu/etdc/view?acc_num=osu1416593665

Abstract Details

2014, Doctor of Philosophy, Ohio State University, Physics.
Semiconductor nanowires hold a wealth of promise for studying the fundamental physics of electron behavior and interactions in a quasi-one dimensional environment and as components in or the foundation of technological advancement in electronic and spintronic devices. Especially in the case of spintronic applications, the crystalline environment must be highly controlled. Spintronic devices often depend on relative phases of spin states which are easily lost in an environment with high scattering probabilities. In any material system, control of the fabrication is the limiting factor to achieving the theoretical characteristics and operation. Bottom-up synthesis of semiconductor nanowires has yet to reach the level of control required for use as a base system in research. Material synthesis that meets the criteria for advanced applications remains a bottle neck in advancing the application of GaAs or any other semiconductor nanowires. We discuss the vapor-liquid-solid (VLS) mechanism and the growth of gallium arsenide and other III-V semiconductors. This mechanism has become a foundation of bottom-up nanowire growth, the physics of which remains the subject of ongoing research. We also discuss metal organic chemical vapor deposition (MOCVD), an epitaxial technique for III-V semiconductor thin films that is prominent in semiconductor nanowire growth. We systematically analyze the effect of core-growth temperature on VLS, epitaxial GaAs/AlGaAs core/shell nanowires in MOCVD by photoluminescence characterization of nanowire ensembles as a function of core growth temperature. To our knowledge, a prior systematic study of the photoluminescence dependence on growth temperature does not exist in the literature. We demonstrate ensemble photoluminescence linewidths competitive with the best single-wire linewidths in the literature. Thus we demonstrate wires of highly uniform characteristics across the growth surface. Our results also indicate that the effect of the growth temperature is coupled to the crystal orientation of the substrate. At low temperatures, nanowires grown on a GaAs (100) surface exhibit a narrower photoluminescence peak at the band edge in a wider temperature window than wires grown on GaAs (111)B. This is contrary to what might be expected given that all the wires grow in the <111> direction and display the same growth rate on both substrate surfaces. Under our conditions, the window in growth temperature for a high optical quality gallium arsenide nanowire is narrow compared to thin film epitaxy. We discuss our methods for successful growth of a novel nanowire device structure by MOCVD. We grow vertical GaAs nanowires embedded in a continuous film of AlGaAs. This structure has thus far only been reported in molecular beam epitaxy, which by its directional nature, lends itself growth in high aspect ratio channels. In addition, this structure has several advantages. First, the 40 nm diameter GaAs nanowires are protected by the in situ AlGaAs growth. Second, the geometry enables use of thin film techniques for device processing to easily control the number of wires to be activated in the device by simply changing the area of the patterned contact. Development of this nanowire-thin-film geometry opens the door for the study of parallel ensembles of nanowires and nanowire heterostructures.
Fengyuan Yang, Professor (Advisor)
Jay Gupta, Professor (Committee Member)
Klaus Honscheid, Professor (Committee Member)
Mohit Randeria, Professor (Committee Member)
130 p.
Physics
Metal Organic Chemical Vapor Deposition; Nanowires; Semiconductor; III-V; Photoluminescence

Recommended Citations

Citations

  • Minutillo, N. G. (2014). The Growth and Characterization of Gallium Arsenide Nanowire Structures by Metal Organic Chemical Vapor Deposition [Doctoral dissertation, Ohio State University]. OhioLINK Electronic Theses and Dissertations Center. http://rave.ohiolink.edu/etdc/view?acc_num=osu1416593665

    APA Style (7th edition)

  • Minutillo, Nicholas. The Growth and Characterization of Gallium Arsenide Nanowire Structures by Metal Organic Chemical Vapor Deposition. 2014. Ohio State University, Doctoral dissertation. OhioLINK Electronic Theses and Dissertations Center, http://rave.ohiolink.edu/etdc/view?acc_num=osu1416593665.

    MLA Style (8th edition)

  • Minutillo, Nicholas. "The Growth and Characterization of Gallium Arsenide Nanowire Structures by Metal Organic Chemical Vapor Deposition." Doctoral dissertation, Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1416593665

    Chicago Manual of Style (17th edition)

osu1416593665
2,382
© 2014, all rights reserved.
This open access ETD is published by The Ohio State University and OhioLINK.