In this work, advanced III-V quantum dot (QD) materials are discussed and examined theoretically. The significance of substrate miscut with regards to QD growth is discussed and previous experimental data are examined to show established trends with regards to favorable miscut degree. In order to examine the miscut effect further, multiple testing techniques are presented which characterize material quality as it pertains to optoelectronic device performance, including optical and electrical spectroscopic methods. The optical probing techniques of photoluminescence (PL) and photoreflectance (PR) are used to experimentally characterize the optical properties of GaAs baseline and InAs/GaAs one-layer QD samples. Experimental results reveal conclusive trends concerning QD energetic transitions and material quality as it relates to substrate miscut. Deep level transient spectroscopy (DLTS) was investigated as an experimental method to inspect possible non-radiative defects or other QD defect properties which may contribute to PL signal degradation in miscut samples. Included in the DLTS evaluation section, I-V and C-V analyses are presented to pinpoint deep traps for profiling, as well as obtain general material parameters and trends. The deep defect profiling suggests differences between miscut samples. The behavior of the reduced PL signal, corresponding to reduced radiative-recombination in certain miscut samples, is discussed as related to the compilation of data obtained through optical and electrical probing.
Library of Congress Subject Headings
Quantum dots--Optical properties; Semiconductors--Design and construction; Substrate noise
Department, Program, or Center
Microelectronic Engineering (KGCOE)
Okvath, Joanne, "The Effects of GaAs substrate miscut on InAs quantum dot optoelectronic properties: Examined by photoreflectance (PR) and deep level transient spectroscopy (DLTS)" (2010). Thesis. Rochester Institute of Technology. Accessed from
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