Open AccessThermoelectric properties of ZnSb films grown by MOCVD
Author(s) -
R. Venkatasubramanian,
E. Watko,
T.S. Colpitts
Publication year - 1997
Language(s) - English
Resource type - Reports
DOI - 10.2172/319831
Subject(s) - seebeck coefficient , thermoelectric effect , materials science , metalorganic vapour phase epitaxy , electrical resistivity and conductivity , dopant , annealing (glass) , analytical chemistry (journal) , thermoelectric materials , thermal conductivity , condensed matter physics , optoelectronics , doping , nanotechnology , metallurgy , composite material , chemistry , epitaxy , electrical engineering , thermodynamics , physics , engineering , layer (electronics) , chromatography
The thermoelectric properties of metallorganic chemical vapor deposited (MOCVD) ZnSb films are reported. The growth conditions necessary to obtain stoichiometric ZnSb films and the effects of various growth parameters on the electrical conductivity and Seebeck coefficients of the films are described. The as-grown ZnSb films are p-type. It was observed that the growth of thicker ZnSb films lead to improved carrier mobilities and lower free-carrier concentrations. The Seebeck coefficient of ZnSb films was found to rise rapidly at approximately 160 to 170 C, with peak Seebeck coefficients as high as 470 {micro}V/K at 220 C. The various growth conditions, including the use of intentional dopants, to improve the Seebeck coefficients at room temperature and above, are discussed. A short annealing of the ZnSb films at temperatures of {approximately} 200 C resulted in reduced free-carrier levels and higher Seebeck coefficients at 300 K. Finally, ZT values based on preliminary thermal conductivity measurements using the 3-{omega} method are reported