Optical measurements and mapping in Ga‐ and Al‐doped ZnO and Sn‐doped In2O3. Issue 7 (27th April 2015)

• Record Type: Journal Article
• Authors: Look, D. C.; Leedy, K. D.
• Is Part Of: Physica status solidi. Volume 212:Issue 7(2015:Jul.)
• Page Start: 1427
• Page End: 1432
• Publication Date: 2015-04-27
• Subjects: Solid state physics -- Periodicals; Solids -- Industrial applications -- Periodicals; 530.41
• DOI: 10.1002/pssa.201532020
• Languages: English
• ISSNs: 1862-6300

Abstract

<abstract abstract-type="main" xml:lang="en"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="pssa201532020-sec-0001" sec-type="section"> <p>Hall‐effect/conductivity measurements in TCO materials such as Ga‐doped ZnO (GZO), Al‐doped ZnO (AZO), and Sn‐doped In<sub>2</sub>O<sub>3</sub> (ITO) determine Hall mobility <italic>μ</italic><sub>H</sub> and sheet carrier concentration <italic>n</italic><sub>s</sub> directly by measurements of current, voltage, and magnetic field. If thickness <italic>d</italic> is known, then <italic>n</italic><sub>s</sub> can be converted into volume concentration <italic>n</italic> = <italic>n</italic><sub>s</sub>/<italic>d</italic>. Optical measurements, on the other hand, determine analogous quantities <italic>μ</italic><sub>opt</sub> and <italic>n</italic><sub>opt</sub> indirectly, usually by invoking the Drude model of the dielectric constant. Here we compare <italic>μ</italic><sub>opt</sub> and <italic>n</italic><sub>opt</sub> obtained by Drude analysis of reflection, transmission, and spectroscopic‐ellipsometry (SE) measurements, with <italic>μ</italic><sub>H</sub> and <italic>n</italic>. Although reasonably good agreement between Hall effect and optical parameters can be obtained with all of these techniques, SE is especially attractive for non‐destructive, high‐density mapping of <italic>μ</italic> and <italic>n</italic>. Moreover, we can use degenerate scattering theory to convert maps of <italic>μ</italic> and <italic>n</italic> into maps of donor and acceptor concentration. This new mapping methodology is applied to GZO and ITO.</p> </sec> </abstract>