Electrical Profiles in GaN/Al2O3 Layers with Conductive Interface Regions


D.C. Look, J. E. Hoelscher
Semiconductor Research Center, Wright State University, Dayton, OH 45435
and
Air Force Research Laboratory, Materials and Manufacturing Directorate, Dayton, OH 45433

J. L. Brown
Air Force Research Laboratory, Materials and Manufacturing Directorate, Dayton, OH 45433

G. D. Via
Air Force Research Laboratory, Sensors Directorate, Dayton, OH 45433

This article was received on Wednesday, April 4, 2001 and accepted on Wednesday, May 9, 2001.

Abstract

Differential Hall-effect measurements are used to obtain profiles of the mobility, µ, and carrier concentration, n, in a 6-µm-thick GaN layer grown on Al2O3 by hydride vapor phase epitaxy (HVPE). In the top 1-µm region (surface), µ approxequal 1000 cm2/V-s and n approxequal 3 x 1016 cm-3, whereas in the bottom 0.75-µm region (interface), µ approxequal 50 cm2/V-s and n approxequal 2 x 1019 cm-3. Throughout the layer, the carrier concentration correlates well with the O and Si concentrations, with [Si] dominant near the surface, and [O] dominant near the interface, proving the shallow-donor nature of O. The average mobility and carrier concentration in the top 5 µm, i.e., the "bulk" region, are close to the values deduced by a much simpler analysis, introduced previously.

Outline

  • Introduction
  • Two-layer Model
  • Differential Hall-effect Model
  • Results and Discussion
  • Conclusions
  • Acknowledgments

    • Linked Pages

    Cite this article as: MRS Internet J. Nitride Semicond. Res. 6, 10(2001).

    last updated Wednesday, May 9, 2001 6:40:43 PM.

    © 2001 The Materials Research Society MRS Internet Journal of Nitride Semiconductor Research