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Efficient Acceptor Activation in AlxGa1−xN/GaN Doped Superlattices

Published online by Cambridge University Press:  03 September 2012

I. D. Goepfert ,
E. F. Schubert ,
A. Osinsky  and
P. E. Norris
I. D. Goepfert
Affiliation:
Department of Electrical and Computer Engineering Boston University, Boston, MA 02215
E. F. Schubert
Affiliation:
Department of Electrical and Computer Engineering Boston University, Boston, MA 02215
A. Osinsky
Affiliation:
NZ Applied Technologies, Woburn, MA 01801
P. E. Norris
Affiliation:
NZ Applied Technologies, Woburn, MA 01801
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Abstract

Mg-doped superlattices consisting of uniformly doped AlxGa1−xN and GaN layers are analyzed by Hall-effect measurements. Acceptor activation energies of 70 meV and 58 meV are obtained for superlattice structures with an Al mole fraction of x = 0.10 and 0.20 in the barrier layers, respectively. These energies are significantly lower than the activation energy measured for Mg-doped GaN thin films. At room temperature, the doped superlattices have free hole concentrations of 2 × 1018 cm−3 and 4 × 1018 cm−3 for x = 0.10 and 0.20, respectively. The increase in hole concentration with Al content of the superlattice is consistent with theory. The room temperature conductivity measured for the superlattice structures are 0.27 S/cm and 0.64 S/cm for an Al mole fraction of x = 0.10 and 0.20, respectively.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 595: Symposium W – GaN and Related Alloys - 1999 , 1999 , F99W3.85
Copyright
Copyright © Materials Research Society 1999

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References

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