SGER: Exploring the Electron and Lattice Dynamics during Ultrafast Laser P-Type-Doping of ZnO

Harvard University, Cambridge MA

Investigators

Abstract

Zinc Oxide (ZnO) is a wide-bandgap semiconductor that has recently seen a resurgence of popularity as a choice material for optoelectronic devices in the blue-to-near-ultraviolet region of the spectrum. Its properties and non-toxicity make it an ideal material for photonic applications. For semiconductors to be useful in most applications it is necessary to add an additional element to the main material, i.e. to dope the semiconductor. This has kept ZnO from being widely used in devices, despite all of its advantages, because there is no reliable and reproducible way to obtain highly p-doped ZnO. This Small Grant for Exploratory Research aims to reveal the dynamics of the electrons and lattice involved in producing p-doped ZnO. Simultaneously with investigating the physics behind ultrafast doping, this project will explore the use of ultrashort laser pulses to produce a highly doped wide-bandgap semiconductor such as p-doped ZnO. The project will provide a graduate student with multidisciplinary skills. This Small Grant for Exploratory Research will investigate the fundamental electronic and lattice properties of a semiconductor as the material interacts with dopants under ultrafast laser irradiation. The measurements will reveal information about the numbers of carriers excited, the relaxation mechanisms by which the material absorbs excess energy, and the timescales in which the lattice incorporates and accommodates dopants. A fundamental understanding of the electronic and lattice dynamics during ultrafast laser doping is critical for further research on highly doped semiconductors. Simultaneously with investigating the physics behind ultrafast doping, this project will explore the use of ultrashort laser pulses to produce a highly doped wide-bandgap semiconductor such as p-doped ZnO. The project will provide a graduate student with multidisciplinary skills.