On the Structure of Micro‐ and Nano‐Crystalline Semiconductors and Semimetals

Abstract

It is shown that the size distribution of the grains of micro-and nanocrystalline semiconductors and semimetals can be determined from a measurement of the dynamical conductivity Re a@). Here 8 has to be larger than the plasma resonance frequency, and the average grain size must be smaller than 1,/2 (A, Fermi wavelength) which is about 100 nm for an electron concentration of 10'' cm-3.

Optical properties of polycrystalline metallic films

“…For isotropic materials, at sufficiently long wavelengths, in the infrared, the ͑transverse͒ optical conductivity converges to the ordinary ͑longitudinal͒ electrical conductivity. Electron transport properties of metal films taking account of grain boundaries have been studied over the years by several authors, using a variety of methods including the Boltzmann transport equation ͑and related approaches͒, [1][2][3][4][5][6][7] the transfer matrix in a onedimensional ͑1D͒ quantum mechanical setting, 8 the energy loss concept, [9][10][11] and the superposition method. 12 Knowledge of the effect of grain boundaries in the electronic transport in these films may be used to obtain information on the microgeometry of the film, 10 analyze the transport properties of nonequilibrium electrons 13 and surface plasmons, 14 to name just a few applications.…”