EFFECT OF FILM THICKNESS ON LOW-ENERGY ELECTRON TRANSMISSION IN THIN CVD DIAMOND FILMS

摘要

Transmission electron spectroscopy is used to examine the low-energy-electron transport and emission properties of thin CVD diamond films. In particular, the intensity and energy distribution of transmitted electrons are measured as a function of film thickness and incident beam parameters. Low-energy transmission is detected in measurements from two films of thickness 0.15 μm and 2.5 μm with similar B concentrations. The transmitted energy distributions are very similar for the two samples and are nearly identical to comparable reflection measurements. The transmitted FWHM is slightly broader for the thinner film (～ 0.8 - 0.9 eV) than for the thicker film (～0.6 - 0.7 eV), and similar transmission yields (≤3 - 5) are obtained. However, different beam energies are required to produce the low-energy transmission. To address this issue, the data is analyzed using an electron penetration model and Monte Carlo simulations, along with a qualitative model of the diamond nanostructure.