Determination of trapping centers in beta-rhombohedral boron

doi:10.1016/0022-3697(72)90003-0

Journal of Physics and Chemistry of Solids

Volume 33, Issue 2, 1972, Pages 245-254

https://doi.org/10.1016/0022-3697(72)90003-0 Get rights and content

Abstract

Trapping levels and their parameters have been studied in high resistivity, undoped beta-rhombohedral boron. The study is performed by means of transient photoconductivity, space-charge-limited currents and thermally-stimulated currents.

The analysis of the results given by the three methods, provides a completely self-consistent model of the trap distribution in energy. A number of specimens were investigated and self-consistent results for all samples were found by the three methods.

Hole trapping centers deeply located in the ‘gap’ are present. In some samples we found an exponential distribution starting from 0·36 eV above the valence band, together with a discrete shallow (0·02–0·05 eV) level. In other samples a discrete level at 0·23 eV from the valence band is observed.

Energy traps for electrons are found at about 0·25 eV below the conduction band.

The experimental results are discussed with respect to the transport properties of boron.

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Determination of trapping centers in beta-rhombohedral boron

Abstract

J. Non Cryst. Solids

Solid St. Electron.

Ferstkorperprobleme

Soviet Phys. Semicond.

Phys. Status Solidi

Phys. Status. Solidi

Phys. Status Solidi

Phys. Rev.

Photoconductivity of Solids

Phys. Rev. Lett.

Phys. Rev.

Phys. Rev.