Electrical, structural and optical properties of amorphous carbon

doi:10.1016/0022-3093(77)90035-7

Journal of Non-Crystalline Solids

Volume 23, Issue 1, January 1977, Pages 21-41

https://doi.org/10.1016/0022-3093(77)90035-7 Get rights and content

Abstract

The planar and transverse electrical resistivity of amorphous carbon (a-C) films getter-sputtered at low temperature (77–95 K) is well-fitted by the expression $ϱ = ϱ_{0} exp (T_{0} /T)^{14}$ The exponent T₀ being approximately the same in both cases (≈ 7 × 10⁷ K) suggests that the amorphous films are isotropic. Films thinner than 600 Å display a two-dimensional hopping conductivity from which one deduces a density of states N(E_F) at the Fermi level of 10¹⁸ eV⁻¹ cm⁻³ and a radius of the localized wave functions (a) of 12 Å. Tunneling experiments and optical absorption measurements are consistent with a pseudogap of approximately 0.8 eV. Electron diffraction experiments indicate that a-C films consist of a mixture of diamond and graphite bonds; this fact taken in the light of the other experiments would suggest that the graphite bonds act as the localized conduction states.

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Electrical, structural and optical properties of amorphous carbon

Abstract

Thin Solid Films

Solid State Commun.

Solid State Commun.

Solid State Commun.

Solid State Commun.

Solid State Commun.

Phil. Mag.

J. Appl. Phys.

Phys. Rev. Letters

Phys. Rev.

Phys. Rev.