Peering down the quantum well
Subtitle: the inner workings of diode lasers revealed through voltage nanoscopy.
Published: 2004
Language: eng
Number of pages: 96
Description: What can be learned of the inner workings of semiconductor lasers using properly-interpreted voltage probing with nanometer resolution?This work makes three contributions. (1) A model is developed to understand the measured quantity of a nanoscopic potential probe placed on a nonequilibrium semiconductor. Governing quantities deep within the device are revealed by voltage probing the surface. (2) The probe-sample interface is investigated experimentally and theoretically to optimize SVM measurements and ensure they are accurate and reproducible. Artifact-free voltage scans of semiconductor devices in operation are obtained at the spatial resolution limit. (3) SVM is applied to directly image parasitic power dissipation at the p-type contact in state-of-the-art quantum well lasers. Previously, such dissipation could only be inferred though experiments on test structures that do not represent actual diode lasers.To address this question, nanoscopic voltage probing is employed. Scanning voltage microscopy (SVM) reveals directly the potential profiles of actively-driven devices, combining high-impedance potentiometry with spatial profiling of atomic force microscopy.This work quantifies both the measured potential and the method used to acquire it, peering directly into the inner workings of semiconductor lasers.
Notes: Adviser: Edward H. Sargent.

Thesis (M.A.Sc.)--University of Toronto, 2004.

Electronic version licensed for access by U. of T. users.

Source: Masters Abstracts International, Volume: 42-06, page: 2293.

MICR copy on microfiche (2 microfiches).