Journal of Electronic Materials

, Volume 41, Issue 5, pp 948–953

Controlling n-Type Carrier Density from Er Doping of InGaAs with MBE Growth Temperature

Authors

    • Materials DepartmentUniversity of California
  • Trevor E. Buehl
    • Materials DepartmentUniversity of California
  • Pernot Gilles
    • Department of Electrical EngineeringUniversity of California
  • Hong Lu
    • Materials DepartmentUniversity of California
  • Ali Shakouri
    • Department of Electrical EngineeringUniversity of California
  • Chris J. Palmstrom
    • Materials DepartmentUniversity of California
    • Department of Electrical and Computer EngineeringUniversity of California
  • John E. Bowers
    • Department of Electrical and Computer EngineeringUniversity of California
  • Arthur C. Gossard
    • Materials DepartmentUniversity of California
    • Department of Electrical and Computer EngineeringUniversity of California
Article

DOI: 10.1007/s11664-012-2050-5

Cite this article as:
Burke, P.G., Buehl, T.E., Gilles, P. et al. Journal of Elec Materi (2012) 41: 948. doi:10.1007/s11664-012-2050-5

Abstract

Under certain growth conditions in molecular beam epitaxy, erbium, indium, gallium, and arsenic form a two-phase composite, consisting of ErAs nanoparticles embedded in dilute Er-doped In0.53Ga0.47As. This paper further explores the effect of growth conditions, specifically growth temperature, on the nanostructure of this material and the resulting thermal and electrical transport properties. For a set of samples grown with substrate temperatures varying from 430°C to 525°C, we find that the thermal conductivity decreases slightly with increasing growth temperature (from 4.8 W/m K to 4.1 W/m K) while the electrical conductivity decreases dramatically with increasing growth temperature (from 2100 S/cm to 110 S/cm), which is largely due to decreasing carrier concentration. At higher growth temperatures, more erbium precipitates out of solution and the size and density of the ErAs nanoparticles increase, as characterized by high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), while the total erbium concentration does not change with growth temperature, as characterized by Rutherford backscatter spectrometry (RBS). Measurement of the erbium concentration by secondary-ion mass spectrometry suggests that the Er bonding configuration changes with growth temperature. These results indicate that increasing the ratio of solute Er atoms in the In0.53Ga0.47As host to precipitated Er atoms in ErAs particles increases the carrier density and electrical conductivity of the total composite material.

Keywords

ErbiumnanoparticlesMBEgrowth temperature dopingthermoelectric

Copyright information

© TMS 2012