| Semiconductor nanostructures have superior electronic and optical properties that are expected to play an important role in 21st century electronic and photonic devices. Recognizing this potential, semiconductor nanostructures have been the focus of research over the past 25 years, and many ultra-high performance devices have been demonstrated. While the potential of this class of devices is clear, their commercial applications have been limited by the lack of a fabrication process suited to economical volume production. The initial method of nanostructure fabrication using electron beam lithography and reactive ion etching is not considered practical due to its high cost and low throughput. The technologies that are considered serious candidates are the nanogrowth techniques where the semiconductor material is synthesized in the size and the shape of the nanostructures. Most of these techniques, however, do not provide any control over nanostructure size and periodicity which are important requirements for device applications.; We have developed a nanostructure fabrication technique that provides excellent control over device size and periodicity, and is appropriate for low cost commercial manufacturing. This technique uses electrochemical synthesis of semiconductor nanostructures in a preformed alumina (Al2O 3) template. The template is created by electrochemically etching, or anodizing, a thin layer of aluminum deposited on a silicon or a glass substrate. When aluminum is anodized, a two dimensional periodic network of Al2 O3 cells with uniform tubular pores is formed, the diameter of which can be precisely varied between 4 nm and 100 nm by controlling the anodization conditions. The semiconductor nanostructures are then created by electrochemically depositing the material inside the pores. This thesis will provide details about the fabrication technique of the template as well as experimental results for optimization of the fabrication technique. |
