Recovery of Quenched Hopping Conduction in GaAs-Layers Grown by Molecular-Beam Epitaxy at 200-Degrees-C

Authors

David C. Look, Wright State University - Main CampusFollow
Z-Q. FangFollow
J. R. Sizelove

Document Type

Article

Publication Date

1-1-1993

Abstract

The dark current at 82 K, in GaAs layers grown by molecular-beam epitaxy at 200 °C and annealed at 550 °C, is reduced by a factor 350 after 5 min of IR (hν<~1.12 eV) light illumination. As temperature is swept upward at 0.2 K/s, the current recovers rapidly near 130 K. A numerical analysis of the current recovery, based on hopping conduction, gives an excellent fit to the data for a thermal recovery rate r=3×10⁸ exp(-0.26/kT), very close to the rate observed for EL2 (As_Ga). This proves that the conduction below 300 K in this material is due to hopping between As_Ga-related centers in their ground states. Variable-range hopping [exp-(T₀/T)^1/4] gives a slightly better fit to the data than nearest-neighbor hopping [exp(-ɛ₃/kT)] in the range T=82-160 K, but the fitted recovery rate is not strongly affected no matter which mechanism is assumed.

Comments

The original publication is available at http://prb.aps.org/abstract/PRB/v47/i3/p1441_1

Repository Citation

Look, D. C., Fang, Z., & Sizelove, J. R. (1993). Recovery of Quenched Hopping Conduction in GaAs-Layers Grown by Molecular-Beam Epitaxy at 200-Degrees-C. Physical Review B, 47 (3), 1441-1443.
https://corescholar.libraries.wright.edu/physics/191

DOI

10.1103/PhysRevB.47.1441